diff options
| author | Anton Khirnov <anton@khirnov.net> | 2020-11-20 09:26:40 +0100 |
|---|---|---|
| committer | Anton Khirnov <anton@khirnov.net> | 2020-11-20 09:29:56 +0100 |
| commit | f55a44acf4c65e6e7534813b09f9b5b50e5796a6 (patch) | |
| tree | 9bf6759d1a837631e88ea9b22c4c6c7de3c7075e | |
| parent | 38c78bd3c33068902347208bb15ad49b65570e9c (diff) | |
Include pyaml directly, not as a submodule.
Its repository is quite big and contains infrastructure we do not need.
We should not need to update it, so just include the source directly.
Also, simplify bin/dotbot.
| -rw-r--r-- | .gitmodules | 4 | ||||
| -rwxr-xr-x | bin/dotbot | 43 | ||||
| m--------- | lib/pyyaml | 0 | ||||
| -rw-r--r-- | yaml/LICENCE | 20 | ||||
| -rw-r--r-- | yaml/README | 1 | ||||
| -rw-r--r-- | yaml/__init__.py | 427 | ||||
| -rw-r--r-- | yaml/composer.py | 139 | ||||
| -rw-r--r-- | yaml/constructor.py | 748 | ||||
| -rw-r--r-- | yaml/cyaml.py | 101 | ||||
| -rw-r--r-- | yaml/dumper.py | 62 | ||||
| -rw-r--r-- | yaml/emitter.py | 1137 | ||||
| -rw-r--r-- | yaml/error.py | 75 | ||||
| -rw-r--r-- | yaml/events.py | 86 | ||||
| -rw-r--r-- | yaml/loader.py | 63 | ||||
| -rw-r--r-- | yaml/nodes.py | 49 | ||||
| -rw-r--r-- | yaml/parser.py | 589 | ||||
| -rw-r--r-- | yaml/reader.py | 185 | ||||
| -rw-r--r-- | yaml/representer.py | 389 | ||||
| -rw-r--r-- | yaml/resolver.py | 227 | ||||
| -rw-r--r-- | yaml/scanner.py | 1435 | ||||
| -rw-r--r-- | yaml/serializer.py | 111 | ||||
| -rw-r--r-- | yaml/tokens.py | 104 |
22 files changed, 5953 insertions, 42 deletions
diff --git a/.gitmodules b/.gitmodules deleted file mode 100644 index ffb9af9..0000000 --- a/.gitmodules +++ /dev/null @@ -1,4 +0,0 @@ -[submodule "lib/pyyaml"] - path = lib/pyyaml - url = https://github.com/yaml/pyyaml - ignore = dirty @@ -1,45 +1,12 @@ -#!/usr/bin/env sh +#!/usr/bin/python3 -# This is a valid shell script and also a valid Python script. When this file -# is executed as a shell script, it finds a python binary and executes this -# file as a Python script, passing along all of the command line arguments. -# When this file is executed as a Python script, it loads and runs Dotbot. This -# is useful because we don't know the name of the python binary. - -''':' # begin python string; this line is interpreted by the shell as `:` -command -v python >/dev/null 2>&1 && exec python "$0" "$@" -command -v python3 >/dev/null 2>&1 && exec python3 "$0" "$@" -command -v python2 >/dev/null 2>&1 && exec python2 "$0" "$@" ->&2 echo "error: cannot find python" -exit 1 -''' - -# python code - -import sys, os +import os +import sys PROJECT_ROOT_DIRECTORY = os.path.dirname( os.path.dirname(os.path.realpath(__file__))) - -def inject(lib_path): - path = os.path.join(PROJECT_ROOT_DIRECTORY, 'lib', lib_path) - sys.path.insert(0, path) - -# version dependent libraries -if sys.version_info[0] >= 3: - inject('pyyaml/lib3') -else: - inject('pyyaml/lib') - -if os.path.exists(os.path.join(PROJECT_ROOT_DIRECTORY, 'dotbot')): - if PROJECT_ROOT_DIRECTORY not in sys.path: - sys.path.insert(0, PROJECT_ROOT_DIRECTORY) - os.putenv('PYTHONPATH', PROJECT_ROOT_DIRECTORY) +sys.path.append(PROJECT_ROOT_DIRECTORY) import dotbot -def main(): - dotbot.cli.main() - -if __name__ == '__main__': - main() +dotbot.cli.main() diff --git a/lib/pyyaml b/lib/pyyaml deleted file mode 160000 -Subproject 2f463cf5b0e98a52bc20e348d1e69761bf263b8 diff --git a/yaml/LICENCE b/yaml/LICENCE new file mode 100644 index 0000000..e8f8805 --- /dev/null +++ b/yaml/LICENCE @@ -0,0 +1,20 @@ +Copyright (c) 2017-2019 Ingy döt Net +Copyright (c) 2006-2016 Kirill Simonov + +Permission is hereby granted, free of charge, to any person obtaining a copy of +this software and associated documentation files (the "Software"), to deal in +the Software without restriction, including without limitation the rights to +use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies +of the Software, and to permit persons to whom the Software is furnished to do +so, subject to the following conditions: + +The above copyright notice and this permission notice shall be included in all +copies or substantial portions of the Software. + +THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR +IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, +FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE +AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER +LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, +OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE +SOFTWARE. diff --git a/yaml/README b/yaml/README new file mode 100644 index 0000000..fa39cee --- /dev/null +++ b/yaml/README @@ -0,0 +1 @@ +This is a copy of python3 source for pyyaml 5.3.1 (538b5c93f7d5dee40322893c1e524e94a4f8bbde) diff --git a/yaml/__init__.py b/yaml/__init__.py new file mode 100644 index 0000000..13d687c --- /dev/null +++ b/yaml/__init__.py @@ -0,0 +1,427 @@ + +from .error import * + +from .tokens import * +from .events import * +from .nodes import * + +from .loader import * +from .dumper import * + +__version__ = '5.3.1' +try: + from .cyaml import * + __with_libyaml__ = True +except ImportError: + __with_libyaml__ = False + +import io + +#------------------------------------------------------------------------------ +# Warnings control +#------------------------------------------------------------------------------ + +# 'Global' warnings state: +_warnings_enabled = { + 'YAMLLoadWarning': True, +} + +# Get or set global warnings' state +def warnings(settings=None): + if settings is None: + return _warnings_enabled + + if type(settings) is dict: + for key in settings: + if key in _warnings_enabled: + _warnings_enabled[key] = settings[key] + +# Warn when load() is called without Loader=... +class YAMLLoadWarning(RuntimeWarning): + pass + +def load_warning(method): + if _warnings_enabled['YAMLLoadWarning'] is False: + return + + import warnings + + message = ( + "calling yaml.%s() without Loader=... is deprecated, as the " + "default Loader is unsafe. Please read " + "https://msg.pyyaml.org/load for full details." + ) % method + + warnings.warn(message, YAMLLoadWarning, stacklevel=3) + +#------------------------------------------------------------------------------ +def scan(stream, Loader=Loader): + """ + Scan a YAML stream and produce scanning tokens. + """ + loader = Loader(stream) + try: + while loader.check_token(): + yield loader.get_token() + finally: + loader.dispose() + +def parse(stream, Loader=Loader): + """ + Parse a YAML stream and produce parsing events. + """ + loader = Loader(stream) + try: + while loader.check_event(): + yield loader.get_event() + finally: + loader.dispose() + +def compose(stream, Loader=Loader): + """ + Parse the first YAML document in a stream + and produce the corresponding representation tree. + """ + loader = Loader(stream) + try: + return loader.get_single_node() + finally: + loader.dispose() + +def compose_all(stream, Loader=Loader): + """ + Parse all YAML documents in a stream + and produce corresponding representation trees. + """ + loader = Loader(stream) + try: + while loader.check_node(): + yield loader.get_node() + finally: + loader.dispose() + +def load(stream, Loader=None): + """ + Parse the first YAML document in a stream + and produce the corresponding Python object. + """ + if Loader is None: + load_warning('load') + Loader = FullLoader + + loader = Loader(stream) + try: + return loader.get_single_data() + finally: + loader.dispose() + +def load_all(stream, Loader=None): + """ + Parse all YAML documents in a stream + and produce corresponding Python objects. + """ + if Loader is None: + load_warning('load_all') + Loader = FullLoader + + loader = Loader(stream) + try: + while loader.check_data(): + yield loader.get_data() + finally: + loader.dispose() + +def full_load(stream): + """ + Parse the first YAML document in a stream + and produce the corresponding Python object. + + Resolve all tags except those known to be + unsafe on untrusted input. + """ + return load(stream, FullLoader) + +def full_load_all(stream): + """ + Parse all YAML documents in a stream + and produce corresponding Python objects. + + Resolve all tags except those known to be + unsafe on untrusted input. + """ + return load_all(stream, FullLoader) + +def safe_load(stream): + """ + Parse the first YAML document in a stream + and produce the corresponding Python object. + + Resolve only basic YAML tags. This is known + to be safe for untrusted input. + """ + return load(stream, SafeLoader) + +def safe_load_all(stream): + """ + Parse all YAML documents in a stream + and produce corresponding Python objects. + + Resolve only basic YAML tags. This is known + to be safe for untrusted input. + """ + return load_all(stream, SafeLoader) + +def unsafe_load(stream): + """ + Parse the first YAML document in a stream + and produce the corresponding Python object. + + Resolve all tags, even those known to be + unsafe on untrusted input. + """ + return load(stream, UnsafeLoader) + +def unsafe_load_all(stream): + """ + Parse all YAML documents in a stream + and produce corresponding Python objects. + + Resolve all tags, even those known to be + unsafe on untrusted input. + """ + return load_all(stream, UnsafeLoader) + +def emit(events, stream=None, Dumper=Dumper, + canonical=None, indent=None, width=None, + allow_unicode=None, line_break=None): + """ + Emit YAML parsing events into a stream. + If stream is None, return the produced string instead. + """ + getvalue = None + if stream is None: + stream = io.StringIO() + getvalue = stream.getvalue + dumper = Dumper(stream, canonical=canonical, indent=indent, width=width, + allow_unicode=allow_unicode, line_break=line_break) + try: + for event in events: + dumper.emit(event) + finally: + dumper.dispose() + if getvalue: + return getvalue() + +def serialize_all(nodes, stream=None, Dumper=Dumper, + canonical=None, indent=None, width=None, + allow_unicode=None, line_break=None, + encoding=None, explicit_start=None, explicit_end=None, + version=None, tags=None): + """ + Serialize a sequence of representation trees into a YAML stream. + If stream is None, return the produced string instead. + """ + getvalue = None + if stream is None: + if encoding is None: + stream = io.StringIO() + else: + stream = io.BytesIO() + getvalue = stream.getvalue + dumper = Dumper(stream, canonical=canonical, indent=indent, width=width, + allow_unicode=allow_unicode, line_break=line_break, + encoding=encoding, version=version, tags=tags, + explicit_start=explicit_start, explicit_end=explicit_end) + try: + dumper.open() + for node in nodes: + dumper.serialize(node) + dumper.close() + finally: + dumper.dispose() + if getvalue: + return getvalue() + +def serialize(node, stream=None, Dumper=Dumper, **kwds): + """ + Serialize a representation tree into a YAML stream. + If stream is None, return the produced string instead. + """ + return serialize_all([node], stream, Dumper=Dumper, **kwds) + +def dump_all(documents, stream=None, Dumper=Dumper, + default_style=None, default_flow_style=False, + canonical=None, indent=None, width=None, + allow_unicode=None, line_break=None, + encoding=None, explicit_start=None, explicit_end=None, + version=None, tags=None, sort_keys=True): + """ + Serialize a sequence of Python objects into a YAML stream. + If stream is None, return the produced string instead. + """ + getvalue = None + if stream is None: + if encoding is None: + stream = io.StringIO() + else: + stream = io.BytesIO() + getvalue = stream.getvalue + dumper = Dumper(stream, default_style=default_style, + default_flow_style=default_flow_style, + canonical=canonical, indent=indent, width=width, + allow_unicode=allow_unicode, line_break=line_break, + encoding=encoding, version=version, tags=tags, + explicit_start=explicit_start, explicit_end=explicit_end, sort_keys=sort_keys) + try: + dumper.open() + for data in documents: + dumper.represent(data) + dumper.close() + finally: + dumper.dispose() + if getvalue: + return getvalue() + +def dump(data, stream=None, Dumper=Dumper, **kwds): + """ + Serialize a Python object into a YAML stream. + If stream is None, return the produced string instead. + """ + return dump_all([data], stream, Dumper=Dumper, **kwds) + +def safe_dump_all(documents, stream=None, **kwds): + """ + Serialize a sequence of Python objects into a YAML stream. + Produce only basic YAML tags. + If stream is None, return the produced string instead. + """ + return dump_all(documents, stream, Dumper=SafeDumper, **kwds) + +def safe_dump(data, stream=None, **kwds): + """ + Serialize a Python object into a YAML stream. + Produce only basic YAML tags. + If stream is None, return the produced string instead. + """ + return dump_all([data], stream, Dumper=SafeDumper, **kwds) + +def add_implicit_resolver(tag, regexp, first=None, + Loader=None, Dumper=Dumper): + """ + Add an implicit scalar detector. + If an implicit scalar value matches the given regexp, + the corresponding tag is assigned to the scalar. + first is a sequence of possible initial characters or None. + """ + if Loader is None: + loader.Loader.add_implicit_resolver(tag, regexp, first) + loader.FullLoader.add_implicit_resolver(tag, regexp, first) + loader.UnsafeLoader.add_implicit_resolver(tag, regexp, first) + else: + Loader.add_implicit_resolver(tag, regexp, first) + Dumper.add_implicit_resolver(tag, regexp, first) + +def add_path_resolver(tag, path, kind=None, Loader=None, Dumper=Dumper): + """ + Add a path based resolver for the given tag. + A path is a list of keys that forms a path + to a node in the representation tree. + Keys can be string values, integers, or None. + """ + if Loader is None: + loader.Loader.add_path_resolver(tag, path, kind) + loader.FullLoader.add_path_resolver(tag, path, kind) + loader.UnsafeLoader.add_path_resolver(tag, path, kind) + else: + Loader.add_path_resolver(tag, path, kind) + Dumper.add_path_resolver(tag, path, kind) + +def add_constructor(tag, constructor, Loader=None): + """ + Add a constructor for the given tag. + Constructor is a function that accepts a Loader instance + and a node object and produces the corresponding Python object. + """ + if Loader is None: + loader.Loader.add_constructor(tag, constructor) + loader.FullLoader.add_constructor(tag, constructor) + loader.UnsafeLoader.add_constructor(tag, constructor) + else: + Loader.add_constructor(tag, constructor) + +def add_multi_constructor(tag_prefix, multi_constructor, Loader=None): + """ + Add a multi-constructor for the given tag prefix. + Multi-constructor is called for a node if its tag starts with tag_prefix. + Multi-constructor accepts a Loader instance, a tag suffix, + and a node object and produces the corresponding Python object. + """ + if Loader is None: + loader.Loader.add_multi_constructor(tag_prefix, multi_constructor) + loader.FullLoader.add_multi_constructor(tag_prefix, multi_constructor) + loader.UnsafeLoader.add_multi_constructor(tag_prefix, multi_constructor) + else: + Loader.add_multi_constructor(tag_prefix, multi_constructor) + +def add_representer(data_type, representer, Dumper=Dumper): + """ + Add a representer for the given type. + Representer is a function accepting a Dumper instance + and an instance of the given data type + and producing the corresponding representation node. + """ + Dumper.add_representer(data_type, representer) + +def add_multi_representer(data_type, multi_representer, Dumper=Dumper): + """ + Add a representer for the given type. + Multi-representer is a function accepting a Dumper instance + and an instance of the given data type or subtype + and producing the corresponding representation node. + """ + Dumper.add_multi_representer(data_type, multi_representer) + +class YAMLObjectMetaclass(type): + """ + The metaclass for YAMLObject. + """ + def __init__(cls, name, bases, kwds): + super(YAMLObjectMetaclass, cls).__init__(name, bases, kwds) + if 'yaml_tag' in kwds and kwds['yaml_tag'] is not None: + if isinstance(cls.yaml_loader, list): + for loader in cls.yaml_loader: + loader.add_constructor(cls.yaml_tag, cls.from_yaml) + else: + cls.yaml_loader.add_constructor(cls.yaml_tag, cls.from_yaml) + + cls.yaml_dumper.add_representer(cls, cls.to_yaml) + +class YAMLObject(metaclass=YAMLObjectMetaclass): + """ + An object that can dump itself to a YAML stream + and load itself from a YAML stream. + """ + + __slots__ = () # no direct instantiation, so allow immutable subclasses + + yaml_loader = [Loader, FullLoader, UnsafeLoader] + yaml_dumper = Dumper + + yaml_tag = None + yaml_flow_style = None + + @classmethod + def from_yaml(cls, loader, node): + """ + Convert a representation node to a Python object. + """ + return loader.construct_yaml_object(node, cls) + + @classmethod + def to_yaml(cls, dumper, data): + """ + Convert a Python object to a representation node. + """ + return dumper.represent_yaml_object(cls.yaml_tag, data, cls, + flow_style=cls.yaml_flow_style) + diff --git a/yaml/composer.py b/yaml/composer.py new file mode 100644 index 0000000..6d15cb4 --- /dev/null +++ b/yaml/composer.py @@ -0,0 +1,139 @@ + +__all__ = ['Composer', 'ComposerError'] + +from .error import MarkedYAMLError +from .events import * +from .nodes import * + +class ComposerError(MarkedYAMLError): + pass + +class Composer: + + def __init__(self): + self.anchors = {} + + def check_node(self): + # Drop the STREAM-START event. + if self.check_event(StreamStartEvent): + self.get_event() + + # If there are more documents available? + return not self.check_event(StreamEndEvent) + + def get_node(self): + # Get the root node of the next document. + if not self.check_event(StreamEndEvent): + return self.compose_document() + + def get_single_node(self): + # Drop the STREAM-START event. + self.get_event() + + # Compose a document if the stream is not empty. + document = None + if not self.check_event(StreamEndEvent): + document = self.compose_document() + + # Ensure that the stream contains no more documents. + if not self.check_event(StreamEndEvent): + event = self.get_event() + raise ComposerError("expected a single document in the stream", + document.start_mark, "but found another document", + event.start_mark) + + # Drop the STREAM-END event. + self.get_event() + + return document + + def compose_document(self): + # Drop the DOCUMENT-START event. + self.get_event() + + # Compose the root node. + node = self.compose_node(None, None) + + # Drop the DOCUMENT-END event. + self.get_event() + + self.anchors = {} + return node + + def compose_node(self, parent, index): + if self.check_event(AliasEvent): + event = self.get_event() + anchor = event.anchor + if anchor not in self.anchors: + raise ComposerError(None, None, "found undefined alias %r" + % anchor, event.start_mark) + return self.anchors[anchor] + event = self.peek_event() + anchor = event.anchor + if anchor is not None: + if anchor in self.anchors: + raise ComposerError("found duplicate anchor %r; first occurrence" + % anchor, self.anchors[anchor].start_mark, + "second occurrence", event.start_mark) + self.descend_resolver(parent, index) + if self.check_event(ScalarEvent): + node = self.compose_scalar_node(anchor) + elif self.check_event(SequenceStartEvent): + node = self.compose_sequence_node(anchor) + elif self.check_event(MappingStartEvent): + node = self.compose_mapping_node(anchor) + self.ascend_resolver() + return node + + def compose_scalar_node(self, anchor): + event = self.get_event() + tag = event.tag + if tag is None or tag == '!': + tag = self.resolve(ScalarNode, event.value, event.implicit) + node = ScalarNode(tag, event.value, + event.start_mark, event.end_mark, style=event.style) + if anchor is not None: + self.anchors[anchor] = node + return node + + def compose_sequence_node(self, anchor): + start_event = self.get_event() + tag = start_event.tag + if tag is None or tag == '!': + tag = self.resolve(SequenceNode, None, start_event.implicit) + node = SequenceNode(tag, [], + start_event.start_mark, None, + flow_style=start_event.flow_style) + if anchor is not None: + self.anchors[anchor] = node + index = 0 + while not self.check_event(SequenceEndEvent): + node.value.append(self.compose_node(node, index)) + index += 1 + end_event = self.get_event() + node.end_mark = end_event.end_mark + return node + + def compose_mapping_node(self, anchor): + start_event = self.get_event() + tag = start_event.tag + if tag is None or tag == '!': + tag = self.resolve(MappingNode, None, start_event.implicit) + node = MappingNode(tag, [], + start_event.start_mark, None, + flow_style=start_event.flow_style) + if anchor is not None: + self.anchors[anchor] = node + while not self.check_event(MappingEndEvent): + #key_event = self.peek_event() + item_key = self.compose_node(node, None) + #if item_key in node.value: + # raise ComposerError("while composing a mapping", start_event.start_mark, + # "found duplicate key", key_event.start_mark) + item_value = self.compose_node(node, item_key) + #node.value[item_key] = item_value + node.value.append((item_key, item_value)) + end_event = self.get_event() + node.end_mark = end_event.end_mark + return node + diff --git a/yaml/constructor.py b/yaml/constructor.py new file mode 100644 index 0000000..1948b12 --- /dev/null +++ b/yaml/constructor.py @@ -0,0 +1,748 @@ + +__all__ = [ + 'BaseConstructor', + 'SafeConstructor', + 'FullConstructor', + 'UnsafeConstructor', + 'Constructor', + 'ConstructorError' +] + +from .error import * +from .nodes import * + +import collections.abc, datetime, base64, binascii, re, sys, types + +class ConstructorError(MarkedYAMLError): + pass + +class BaseConstructor: + + yaml_constructors = {} + yaml_multi_constructors = {} + + def __init__(self): + self.constructed_objects = {} + self.recursive_objects = {} + self.state_generators = [] + self.deep_construct = False + + def check_data(self): + # If there are more documents available? + return self.check_node() + + def check_state_key(self, key): + """Block special attributes/methods from being set in a newly created + object, to prevent user-controlled methods from being called during + deserialization""" + if self.get_state_keys_blacklist_regexp().match(key): + raise ConstructorError(None, None, + "blacklisted key '%s' in instance state found" % (key,), None) + + def get_data(self): + # Construct and return the next document. + if self.check_node(): + return self.construct_document(self.get_node()) + + def get_single_data(self): + # Ensure that the stream contains a single document and construct it. + node = self.get_single_node() + if node is not None: + return self.construct_document(node) + return None + + def construct_document(self, node): + data = self.construct_object(node) + while self.state_generators: + state_generators = self.state_generators + self.state_generators = [] + for generator in state_generators: + for dummy in generator: + pass + self.constructed_objects = {} + self.recursive_objects = {} + self.deep_construct = False + return data + + def construct_object(self, node, deep=False): + if node in self.constructed_objects: + return self.constructed_objects[node] + if deep: + old_deep = self.deep_construct + self.deep_construct = True + if node in self.recursive_objects: + raise ConstructorError(None, None, + "found unconstructable recursive node", node.start_mark) + self.recursive_objects[node] = None + constructor = None + tag_suffix = None + if node.tag in self.yaml_constructors: + constructor = self.yaml_constructors[node.tag] + else: + for tag_prefix in self.yaml_multi_constructors: + if tag_prefix is not None and node.tag.startswith(tag_prefix): + tag_suffix = node.tag[len(tag_prefix):] + constructor = self.yaml_multi_constructors[tag_prefix] + break + else: + if None in self.yaml_multi_constructors: + tag_suffix = node.tag + constructor = self.yaml_multi_constructors[None] + elif None in self.yaml_constructors: + constructor = self.yaml_constructors[None] + elif isinstance(node, ScalarNode): + constructor = self.__class__.construct_scalar + elif isinstance(node, SequenceNode): + constructor = self.__class__.construct_sequence + elif isinstance(node, MappingNode): + constructor = self.__class__.construct_mapping + if tag_suffix is None: + data = constructor(self, node) + else: + data = constructor(self, tag_suffix, node) + if isinstance(data, types.GeneratorType): + generator = data + data = next(generator) + if self.deep_construct: + for dummy in generator: + pass + else: + self.state_generators.append(generator) + self.constructed_objects[node] = data + del self.recursive_objects[node] + if deep: + self.deep_construct = old_deep + return data + + def construct_scalar(self, node): + if not isinstance(node, ScalarNode): + raise ConstructorError(None, None, + "expected a scalar node, but found %s" % node.id, + node.start_mark) + return node.value + + def construct_sequence(self, node, deep=False): + if not isinstance(node, SequenceNode): + raise ConstructorError(None, None, + "expected a sequence node, but found %s" % node.id, + node.start_mark) + return [self.construct_object(child, deep=deep) + for child in node.value] + + def construct_mapping(self, node, deep=False): + if not isinstance(node, MappingNode): + raise ConstructorError(None, None, + "expected a mapping node, but found %s" % node.id, + node.start_mark) + mapping = {} + for key_node, value_node in node.value: + key = self.construct_object(key_node, deep=deep) + if not isinstance(key, collections.abc.Hashable): + raise ConstructorError("while constructing a mapping", node.start_mark, + "found unhashable key", key_node.start_mark) + value = self.construct_object(value_node, deep=deep) + mapping[key] = value + return mapping + + def construct_pairs(self, node, deep=False): + if not isinstance(node, MappingNode): + raise ConstructorError(None, None, + "expected a mapping node, but found %s" % node.id, + node.start_mark) + pairs = [] + for key_node, value_node in node.value: + key = self.construct_object(key_node, deep=deep) + value = self.construct_object(value_node, deep=deep) + pairs.append((key, value)) + return pairs + + @classmethod + def add_constructor(cls, tag, constructor): + if not 'yaml_constructors' in cls.__dict__: + cls.yaml_constructors = cls.yaml_constructors.copy() + cls.yaml_constructors[tag] = constructor + + @classmethod + def add_multi_constructor(cls, tag_prefix, multi_constructor): + if not 'yaml_multi_constructors' in cls.__dict__: + cls.yaml_multi_constructors = cls.yaml_multi_constructors.copy() + cls.yaml_multi_constructors[tag_prefix] = multi_constructor + +class SafeConstructor(BaseConstructor): + + def construct_scalar(self, node): + if isinstance(node, MappingNode): + for key_node, value_node in node.value: + if key_node.tag == 'tag:yaml.org,2002:value': + return self.construct_scalar(value_node) + return super().construct_scalar(node) + + def flatten_mapping(self, node): + merge = [] + index = 0 + while index < len(node.value): + key_node, value_node = node.value[index] + if key_node.tag == 'tag:yaml.org,2002:merge': + del node.value[index] + if isinstance(value_node, MappingNode): + self.flatten_mapping(value_node) + merge.extend(value_node.value) + elif isinstance(value_node, SequenceNode): + submerge = [] + for subnode in value_node.value: + if not isinstance(subnode, MappingNode): + raise ConstructorError("while constructing a mapping", + node.start_mark, + "expected a mapping for merging, but found %s" + % subnode.id, subnode.start_mark) + self.flatten_mapping(subnode) + submerge.append(subnode.value) + submerge.reverse() + for value in submerge: + merge.extend(value) + else: + raise ConstructorError("while constructing a mapping", node.start_mark, + "expected a mapping or list of mappings for merging, but found %s" + % value_node.id, value_node.start_mark) + elif key_node.tag == 'tag:yaml.org,2002:value': + key_node.tag = 'tag:yaml.org,2002:str' + index += 1 + else: + index += 1 + if merge: + node.value = merge + node.value + + def construct_mapping(self, node, deep=False): + if isinstance(node, MappingNode): + self.flatten_mapping(node) + return super().construct_mapping(node, deep=deep) + + def construct_yaml_null(self, node): + self.construct_scalar(node) + return None + + bool_values = { + 'yes': True, + 'no': False, + 'true': True, + 'false': False, + 'on': True, + 'off': False, + } + + def construct_yaml_bool(self, node): + value = self.construct_scalar(node) + return self.bool_values[value.lower()] + + def construct_yaml_int(self, node): + value = self.construct_scalar(node) + value = value.replace('_', '') + sign = +1 + if value[0] == '-': + sign = -1 + if value[0] in '+-': + value = value[1:] + if value == '0': + return 0 + elif value.startswith('0b'): + return sign*int(value[2:], 2) + elif value.startswith('0x'): + return sign*int(value[2:], 16) + elif value[0] == '0': + return sign*int(value, 8) + elif ':' in value: + digits = [int(part) for part in value.split(':')] + digits.reverse() + base = 1 + value = 0 + for digit in digits: + value += digit*base + base *= 60 + return sign*value + else: + return sign*int(value) + + inf_value = 1e300 + while inf_value != inf_value*inf_value: + inf_value *= inf_value + nan_value = -inf_value/inf_value # Trying to make a quiet NaN (like C99). + + def construct_yaml_float(self, node): + value = self.construct_scalar(node) + value = value.replace('_', '').lower() + sign = +1 + if value[0] == '-': + sign = -1 + if value[0] in '+-': + value = value[1:] + if value == '.inf': + return sign*self.inf_value + elif value == '.nan': + return self.nan_value + elif ':' in value: + digits = [float(part) for part in value.split(':')] + digits.reverse() + base = 1 + value = 0.0 + for digit in digits: + value += digit*base + base *= 60 + return sign*value + else: + return sign*float(value) + + def construct_yaml_binary(self, node): + try: + value = self.construct_scalar(node).encode('ascii') + except UnicodeEncodeError as exc: + raise ConstructorError(None, None, + "failed to convert base64 data into ascii: %s" % exc, + node.start_mark) + try: + if hasattr(base64, 'decodebytes'): + return base64.decodebytes(value) + else: + return base64.decodestring(value) + except binascii.Error as exc: + raise ConstructorError(None, None, + "failed to decode base64 data: %s" % exc, node.start_mark) + + timestamp_regexp = re.compile( + r'''^(?P<year>[0-9][0-9][0-9][0-9]) + -(?P<month>[0-9][0-9]?) + -(?P<day>[0-9][0-9]?) + (?:(?:[Tt]|[ \t]+) + (?P<hour>[0-9][0-9]?) + :(?P<minute>[0-9][0-9]) + :(?P<second>[0-9][0-9]) + (?:\.(?P<fraction>[0-9]*))? + (?:[ \t]*(?P<tz>Z|(?P<tz_sign>[-+])(?P<tz_hour>[0-9][0-9]?) + (?::(?P<tz_minute>[0-9][0-9]))?))?)?$''', re.X) + + def construct_yaml_timestamp(self, node): + value = self.construct_scalar(node) + match = self.timestamp_regexp.match(node.value) + values = match.groupdict() + year = int(values['year']) + month = int(values['month']) + day = int(values['day']) + if not values['hour']: + return datetime.date(year, month, day) + hour = int(values['hour']) + minute = int(values['minute']) + second = int(values['second']) + fraction = 0 + tzinfo = None + if values['fraction']: + fraction = values['fraction'][:6] + while len(fraction) < 6: + fraction += '0' + fraction = int(fraction) + if values['tz_sign']: + tz_hour = int(values['tz_hour']) + tz_minute = int(values['tz_minute'] or 0) + delta = datetime.timedelta(hours=tz_hour, minutes=tz_minute) + if values['tz_sign'] == '-': + delta = -delta + tzinfo = datetime.timezone(delta) + elif values['tz']: + tzinfo = datetime.timezone.utc + return datetime.datetime(year, month, day, hour, minute, second, fraction, + tzinfo=tzinfo) + + def construct_yaml_omap(self, node): + # Note: we do not check for duplicate keys, because it's too + # CPU-expensive. + omap = [] + yield omap + if not isinstance(node, SequenceNode): + raise ConstructorError("while constructing an ordered map", node.start_mark, + "expected a sequence, but found %s" % node.id, node.start_mark) + for subnode in node.value: + if not isinstance(subnode, MappingNode): + raise ConstructorError("while constructing an ordered map", node.start_mark, + "expected a mapping of length 1, but found %s" % subnode.id, + subnode.start_mark) + if len(subnode.value) != 1: + raise ConstructorError("while constructing an ordered map", node.start_mark, + "expected a single mapping item, but found %d items" % len(subnode.value), + subnode.start_mark) + key_node, value_node = subnode.value[0] + key = self.construct_object(key_node) + value = self.construct_object(value_node) + omap.append((key, value)) + + def construct_yaml_pairs(self, node): + # Note: the same code as `construct_yaml_omap`. + pairs = [] + yield pairs + if not isinstance(node, SequenceNode): + raise ConstructorError("while constructing pairs", node.start_mark, + "expected a sequence, but found %s" % node.id, node.start_mark) + for subnode in node.value: + if not isinstance(subnode, MappingNode): + raise ConstructorError("while constructing pairs", node.start_mark, + "expected a mapping of length 1, but found %s" % subnode.id, + subnode.start_mark) + if len(subnode.value) != 1: + raise ConstructorError("while constructing pairs", node.start_mark, + "expected a single mapping item, but found %d items" % len(subnode.value), + subnode.start_mark) + key_node, value_node = subnode.value[0] + key = self.construct_object(key_node) + value = self.construct_object(value_node) + pairs.append((key, value)) + + def construct_yaml_set(self, node): + data = set() + yield data + value = self.construct_mapping(node) + data.update(value) + + def construct_yaml_str(self, node): + return self.construct_scalar(node) + + def construct_yaml_seq(self, node): + data = [] + yield data + data.extend(self.construct_sequence(node)) + + def construct_yaml_map(self, node): + data = {} + yield data + value = self.construct_mapping(node) + data.update(value) + + def construct_yaml_object(self, node, cls): + data = cls.__new__(cls) + yield data + if hasattr(data, '__setstate__'): + state = self.construct_mapping(node, deep=True) + data.__setstate__(state) + else: + state = self.construct_mapping(node) + data.__dict__.update(state) + + def construct_undefined(self, node): + raise ConstructorError(None, None, + "could not determine a constructor for the tag %r" % node.tag, + node.start_mark) + +SafeConstructor.add_constructor( + 'tag:yaml.org,2002:null', + SafeConstructor.construct_yaml_null) + +SafeConstructor.add_constructor( + 'tag:yaml.org,2002:bool', + SafeConstructor.construct_yaml_bool) + +SafeConstructor.add_constructor( + 'tag:yaml.org,2002:int', + SafeConstructor.construct_yaml_int) + +SafeConstructor.add_constructor( + 'tag:yaml.org,2002:float', + SafeConstructor.construct_yaml_float) + +SafeConstructor.add_constructor( + 'tag:yaml.org,2002:binary', + SafeConstructor.construct_yaml_binary) + +SafeConstructor.add_constructor( + 'tag:yaml.org,2002:timestamp', + SafeConstructor.construct_yaml_timestamp) + +SafeConstructor.add_constructor( + 'tag:yaml.org,2002:omap', + SafeConstructor.construct_yaml_omap) + +SafeConstructor.add_constructor( + 'tag:yaml.org,2002:pairs', + SafeConstructor.construct_yaml_pairs) + +SafeConstructor.add_constructor( + 'tag:yaml.org,2002:set', + SafeConstructor.construct_yaml_set) + +SafeConstructor.add_constructor( + 'tag:yaml.org,2002:str', + SafeConstructor.construct_yaml_str) + +SafeConstructor.add_constructor( + 'tag:yaml.org,2002:seq', + SafeConstructor.construct_yaml_seq) + +SafeConstructor.add_constructor( + 'tag:yaml.org,2002:map', + SafeConstructor.construct_yaml_map) + +SafeConstructor.add_constructor(None, + SafeConstructor.construct_undefined) + +class FullConstructor(SafeConstructor): + # 'extend' is blacklisted because it is used by + # construct_python_object_apply to add `listitems` to a newly generate + # python instance + def get_state_keys_blacklist(self): + return ['^extend$', '^__.*__$'] + + def get_state_keys_blacklist_regexp(self): + if not hasattr(self, 'state_keys_blacklist_regexp'): + self.state_keys_blacklist_regexp = re.compile('(' + '|'.join(self.get_state_keys_blacklist()) + ')') + return self.state_keys_blacklist_regexp + + def construct_python_str(self, node): + return self.construct_scalar(node) + + def construct_python_unicode(self, node): + return self.construct_scalar(node) + + def construct_python_bytes(self, node): + try: + value = self.construct_scalar(node).encode('ascii') + except UnicodeEncodeError as exc: + raise ConstructorError(None, None, + "failed to convert base64 data into ascii: %s" % exc, + node.start_mark) + try: + if hasattr(base64, 'decodebytes'): + return base64.decodebytes(value) + else: + return base64.decodestring(value) + except binascii.Error as exc: + raise ConstructorError(None, None, + "failed to decode base64 data: %s" % exc, node.start_mark) + + def construct_python_long(self, node): + return self.construct_yaml_int(node) + + def construct_python_complex(self, node): + return complex(self.construct_scalar(node)) + + def construct_python_tuple(self, node): + return tuple(self.construct_sequence(node)) + + def find_python_module(self, name, mark, unsafe=False): + if not name: + raise ConstructorError("while constructing a Python module", mark, + "expected non-empty name appended to the tag", mark) + if unsafe: + try: + __import__(name) + except ImportError as exc: + raise ConstructorError("while constructing a Python module", mark, + "cannot find module %r (%s)" % (name, exc), mark) + if name not in sys.modules: + raise ConstructorError("while constructing a Python module", mark, + "module %r is not imported" % name, mark) + return sys.modules[name] + + def find_python_name(self, name, mark, unsafe=False): + if not name: + raise ConstructorError("while constructing a Python object", mark, + "expected non-empty name appended to the tag", mark) + if '.' in name: + module_name, object_name = name.rsplit('.', 1) + else: + module_name = 'builtins' + object_name = name + if unsafe: + try: + __import__(module_name) + except ImportError as exc: + raise ConstructorError("while constructing a Python object", mark, + "cannot find module %r (%s)" % (module_name, exc), mark) + if module_name not in sys.modules: + raise ConstructorError("while constructing a Python object", mark, + "module %r is not imported" % module_name, mark) + module = sys.modules[module_name] + if not hasattr(module, object_name): + raise ConstructorError("while constructing a Python object", mark, + "cannot find %r in the module %r" + % (object_name, module.__name__), mark) + return getattr(module, object_name) + + def construct_python_name(self, suffix, node): + value = self.construct_scalar(node) + if value: + raise ConstructorError("while constructing a Python name", node.start_mark, + "expected the empty value, but found %r" % value, node.start_mark) + return self.find_python_name(suffix, node.start_mark) + + def construct_python_module(self, suffix, node): + value = self.construct_scalar(node) + if value: + raise ConstructorError("while constructing a Python module", node.start_mark, + "expected the empty value, but found %r" % value, node.start_mark) + return self.find_python_module(suffix, node.start_mark) + + def make_python_instance(self, suffix, node, + args=None, kwds=None, newobj=False, unsafe=False): + if not args: + args = [] + if not kwds: + kwds = {} + cls = self.find_python_name(suffix, node.start_mark) + if not (unsafe or isinstance(cls, type)): + raise ConstructorError("while constructing a Python instance", node.start_mark, + "expected a class, but found %r" % type(cls), + node.start_mark) + if newobj and isinstance(cls, type): + return cls.__new__(cls, *args, **kwds) + else: + return cls(*args, **kwds) + + def set_python_instance_state(self, instance, state, unsafe=False): + if hasattr(instance, '__setstate__'): + instance.__setstate__(state) + else: + slotstate = {} + if isinstance(state, tuple) and len(state) == 2: + state, slotstate = state + if hasattr(instance, '__dict__'): + if not unsafe and state: + for key in state.keys(): + self.check_state_key(key) + instance.__dict__.update(state) + elif state: + slotstate.update(state) + for key, value in slotstate.items(): + if not unsafe: + self.check_state_key(key) + setattr(instance, key, value) + + def construct_python_object(self, suffix, node): + # Format: + # !!python/object:module.name { ... state ... } + instance = self.make_python_instance(suffix, node, newobj=True) + yield instance + deep = hasattr(instance, '__setstate__') + state = self.construct_mapping(node, deep=deep) + self.set_python_instance_state(instance, state) + + def construct_python_object_apply(self, suffix, node, newobj=False): + # Format: + # !!python/object/apply # (or !!python/object/new) + # args: [ ... arguments ... ] + # kwds: { ... keywords ... } + # state: ... state ... + # listitems: [ ... listitems ... ] + # dictitems: { ... dictitems ... } + # or short format: + # !!python/object/apply [ ... arguments ... ] + # The difference between !!python/object/apply and !!python/object/new + # is how an object is created, check make_python_instance for details. + if isinstance(node, SequenceNode): + args = self.construct_sequence(node, deep=True) + kwds = {} + state = {} + listitems = [] + dictitems = {} + else: + value = self.construct_mapping(node, deep=True) + args = value.get('args', []) + kwds = value.get('kwds', {}) + state = value.get('state', {}) + listitems = value.get('listitems', []) + dictitems = value.get('dictitems', {}) + instance = self.make_python_instance(suffix, node, args, kwds, newobj) + if state: + self.set_python_instance_state(instance, state) + if listitems: + instance.extend(listitems) + if dictitems: + for key in dictitems: + instance[key] = dictitems[key] + return instance + + def construct_python_object_new(self, suffix, node): + return self.construct_python_object_apply(suffix, node, newobj=True) + +FullConstructor.add_constructor( + 'tag:yaml.org,2002:python/none', + FullConstructor.construct_yaml_null) + +FullConstructor.add_constructor( + 'tag:yaml.org,2002:python/bool', + FullConstructor.construct_yaml_bool) + +FullConstructor.add_constructor( + 'tag:yaml.org,2002:python/str', + FullConstructor.construct_python_str) + +FullConstructor.add_constructor( + 'tag:yaml.org,2002:python/unicode', + FullConstructor.construct_python_unicode) + +FullConstructor.add_constructor( + 'tag:yaml.org,2002:python/bytes', + FullConstructor.construct_python_bytes) + +FullConstructor.add_constructor( + 'tag:yaml.org,2002:python/int', + FullConstructor.construct_yaml_int) + +FullConstructor.add_constructor( + 'tag:yaml.org,2002:python/long', + FullConstructor.construct_python_long) + +FullConstructor.add_constructor( + 'tag:yaml.org,2002:python/float', + FullConstructor.construct_yaml_float) + +FullConstructor.add_constructor( + 'tag:yaml.org,2002:python/complex', + FullConstructor.construct_python_complex) + +FullConstructor.add_constructor( + 'tag:yaml.org,2002:python/list', + FullConstructor.construct_yaml_seq) + +FullConstructor.add_constructor( + 'tag:yaml.org,2002:python/tuple', + FullConstructor.construct_python_tuple) + +FullConstructor.add_constructor( + 'tag:yaml.org,2002:python/dict', + FullConstructor.construct_yaml_map) + +FullConstructor.add_multi_constructor( + 'tag:yaml.org,2002:python/name:', + FullConstructor.construct_python_name) + +FullConstructor.add_multi_constructor( + 'tag:yaml.org,2002:python/module:', + FullConstructor.construct_python_module) + +FullConstructor.add_multi_constructor( + 'tag:yaml.org,2002:python/object:', + FullConstructor.construct_python_object) + +FullConstructor.add_multi_constructor( + 'tag:yaml.org,2002:python/object/new:', + FullConstructor.construct_python_object_new) + +class UnsafeConstructor(FullConstructor): + + def find_python_module(self, name, mark): + return super(UnsafeConstructor, self).find_python_module(name, mark, unsafe=True) + + def find_python_name(self, name, mark): + return super(UnsafeConstructor, self).find_python_name(name, mark, unsafe=True) + + def make_python_instance(self, suffix, node, args=None, kwds=None, newobj=False): + return super(UnsafeConstructor, self).make_python_instance( + suffix, node, args, kwds, newobj, unsafe=True) + + def set_python_instance_state(self, instance, state): + return super(UnsafeConstructor, self).set_python_instance_state( + instance, state, unsafe=True) + +UnsafeConstructor.add_multi_constructor( + 'tag:yaml.org,2002:python/object/apply:', + UnsafeConstructor.construct_python_object_apply) + +# Constructor is same as UnsafeConstructor. Need to leave this in place in case +# people have extended it directly. +class Constructor(UnsafeConstructor): + pass diff --git a/yaml/cyaml.py b/yaml/cyaml.py new file mode 100644 index 0000000..1e606c7 --- /dev/null +++ b/yaml/cyaml.py @@ -0,0 +1,101 @@ + +__all__ = [ + 'CBaseLoader', 'CSafeLoader', 'CFullLoader', 'CUnsafeLoader', 'CLoader', + 'CBaseDumper', 'CSafeDumper', 'CDumper' +] + +from _yaml import CParser, CEmitter + +from .constructor import * + +from .serializer import * +from .representer import * + +from .resolver import * + +class CBaseLoader(CParser, BaseConstructor, BaseResolver): + + def __init__(self, stream): + CParser.__init__(self, stream) + BaseConstructor.__init__(self) + BaseResolver.__init__(self) + +class CSafeLoader(CParser, SafeConstructor, Resolver): + + def __init__(self, stream): + CParser.__init__(self, stream) + SafeConstructor.__init__(self) + Resolver.__init__(self) + +class CFullLoader(CParser, FullConstructor, Resolver): + + def __init__(self, stream): + CParser.__init__(self, stream) + FullConstructor.__init__(self) + Resolver.__init__(self) + +class CUnsafeLoader(CParser, UnsafeConstructor, Resolver): + + def __init__(self, stream): + CParser.__init__(self, stream) + UnsafeConstructor.__init__(self) + Resolver.__init__(self) + +class CLoader(CParser, Constructor, Resolver): + + def __init__(self, stream): + CParser.__init__(self, stream) + Constructor.__init__(self) + Resolver.__init__(self) + +class CBaseDumper(CEmitter, BaseRepresenter, BaseResolver): + + def __init__(self, stream, + default_style=None, default_flow_style=False, + canonical=None, indent=None, width=None, + allow_unicode=None, line_break=None, + encoding=None, explicit_start=None, explicit_end=None, + version=None, tags=None, sort_keys=True): + CEmitter.__init__(self, stream, canonical=canonical, + indent=indent, width=width, encoding=encoding, + allow_unicode=allow_unicode, line_break=line_break, + explicit_start=explicit_start, explicit_end=explicit_end, + version=version, tags=tags) + Representer.__init__(self, default_style=default_style, + default_flow_style=default_flow_style, sort_keys=sort_keys) + Resolver.__init__(self) + +class CSafeDumper(CEmitter, SafeRepresenter, Resolver): + + def __init__(self, stream, + default_style=None, default_flow_style=False, + canonical=None, indent=None, width=None, + allow_unicode=None, line_break=None, + encoding=None, explicit_start=None, explicit_end=None, + version=None, tags=None, sort_keys=True): + CEmitter.__init__(self, stream, canonical=canonical, + indent=indent, width=width, encoding=encoding, + allow_unicode=allow_unicode, line_break=line_break, + explicit_start=explicit_start, explicit_end=explicit_end, + version=version, tags=tags) + SafeRepresenter.__init__(self, default_style=default_style, + default_flow_style=default_flow_style, sort_keys=sort_keys) + Resolver.__init__(self) + +class CDumper(CEmitter, Serializer, Representer, Resolver): + + def __init__(self, stream, + default_style=None, default_flow_style=False, + canonical=None, indent=None, width=None, + allow_unicode=None, line_break=None, + encoding=None, explicit_start=None, explicit_end=None, + version=None, tags=None, sort_keys=True): + CEmitter.__init__(self, stream, canonical=canonical, + indent=indent, width=width, encoding=encoding, + allow_unicode=allow_unicode, line_break=line_break, + explicit_start=explicit_start, explicit_end=explicit_end, + version=version, tags=tags) + Representer.__init__(self, default_style=default_style, + default_flow_style=default_flow_style, sort_keys=sort_keys) + Resolver.__init__(self) + diff --git a/yaml/dumper.py b/yaml/dumper.py new file mode 100644 index 0000000..6aadba5 --- /dev/null +++ b/yaml/dumper.py @@ -0,0 +1,62 @@ + +__all__ = ['BaseDumper', 'SafeDumper', 'Dumper'] + +from .emitter import * +from .serializer import * +from .representer import * +from .resolver import * + +class BaseDumper(Emitter, Serializer, BaseRepresenter, BaseResolver): + + def __init__(self, stream, + default_style=None, default_flow_style=False, + canonical=None, indent=None, width=None, + allow_unicode=None, line_break=None, + encoding=None, explicit_start=None, explicit_end=None, + version=None, tags=None, sort_keys=True): + Emitter.__init__(self, stream, canonical=canonical, + indent=indent, width=width, + allow_unicode=allow_unicode, line_break=line_break) + Serializer.__init__(self, encoding=encoding, + explicit_start=explicit_start, explicit_end=explicit_end, + version=version, tags=tags) + Representer.__init__(self, default_style=default_style, + default_flow_style=default_flow_style, sort_keys=sort_keys) + Resolver.__init__(self) + +class SafeDumper(Emitter, Serializer, SafeRepresenter, Resolver): + + def __init__(self, stream, + default_style=None, default_flow_style=False, + canonical=None, indent=None, width=None, + allow_unicode=None, line_break=None, + encoding=None, explicit_start=None, explicit_end=None, + version=None, tags=None, sort_keys=True): + Emitter.__init__(self, stream, canonical=canonical, + indent=indent, width=width, + allow_unicode=allow_unicode, line_break=line_break) + Serializer.__init__(self, encoding=encoding, + explicit_start=explicit_start, explicit_end=explicit_end, + version=version, tags=tags) + SafeRepresenter.__init__(self, default_style=default_style, + default_flow_style=default_flow_style, sort_keys=sort_keys) + Resolver.__init__(self) + +class Dumper(Emitter, Serializer, Representer, Resolver): + + def __init__(self, stream, + default_style=None, default_flow_style=False, + canonical=None, indent=None, width=None, + allow_unicode=None, line_break=None, + encoding=None, explicit_start=None, explicit_end=None, + version=None, tags=None, sort_keys=True): + Emitter.__init__(self, stream, canonical=canonical, + indent=indent, width=width, + allow_unicode=allow_unicode, line_break=line_break) + Serializer.__init__(self, encoding=encoding, + explicit_start=explicit_start, explicit_end=explicit_end, + version=version, tags=tags) + Representer.__init__(self, default_style=default_style, + default_flow_style=default_flow_style, sort_keys=sort_keys) + Resolver.__init__(self) + diff --git a/yaml/emitter.py b/yaml/emitter.py new file mode 100644 index 0000000..a664d01 --- /dev/null +++ b/yaml/emitter.py @@ -0,0 +1,1137 @@ + +# Emitter expects events obeying the following grammar: +# stream ::= STREAM-START document* STREAM-END +# document ::= DOCUMENT-START node DOCUMENT-END +# node ::= SCALAR | sequence | mapping +# sequence ::= SEQUENCE-START node* SEQUENCE-END +# mapping ::= MAPPING-START (node node)* MAPPING-END + +__all__ = ['Emitter', 'EmitterError'] + +from .error import YAMLError +from .events import * + +class EmitterError(YAMLError): + pass + +class ScalarAnalysis: + def __init__(self, scalar, empty, multiline, + allow_flow_plain, allow_block_plain, + allow_single_quoted, allow_double_quoted, + allow_block): + self.scalar = scalar + self.empty = empty + self.multiline = multiline + self.allow_flow_plain = allow_flow_plain + self.allow_block_plain = allow_block_plain + self.allow_single_quoted = allow_single_quoted + self.allow_double_quoted = allow_double_quoted + self.allow_block = allow_block + +class Emitter: + + DEFAULT_TAG_PREFIXES = { + '!' : '!', + 'tag:yaml.org,2002:' : '!!', + } + + def __init__(self, stream, canonical=None, indent=None, width=None, + allow_unicode=None, line_break=None): + + # The stream should have the methods `write` and possibly `flush`. + self.stream = stream + + # Encoding can be overridden by STREAM-START. + self.encoding = None + + # Emitter is a state machine with a stack of states to handle nested + # structures. + self.states = [] + self.state = self.expect_stream_start + + # Current event and the event queue. + self.events = [] + self.event = None + + # The current indentation level and the stack of previous indents. + self.indents = [] + self.indent = None + + # Flow level. + self.flow_level = 0 + + # Contexts. + self.root_context = False + self.sequence_context = False + self.mapping_context = False + self.simple_key_context = False + + # Characteristics of the last emitted character: + # - current position. + # - is it a whitespace? + # - is it an indention character + # (indentation space, '-', '?', or ':')? + self.line = 0 + self.column = 0 + self.whitespace = True + self.indention = True + + # Whether the document requires an explicit document indicator + self.open_ended = False + + # Formatting details. + self.canonical = canonical + self.allow_unicode = allow_unicode + self.best_indent = 2 + if indent and 1 < indent < 10: + self.best_indent = indent + self.best_width = 80 + if width and width > self.best_indent*2: + self.best_width = width + self.best_line_break = '\n' + if line_break in ['\r', '\n', '\r\n']: + self.best_line_break = line_break + + # Tag prefixes. + self.tag_prefixes = None + + # Prepared anchor and tag. + self.prepared_anchor = None + self.prepared_tag = None + + # Scalar analysis and style. + self.analysis = None + self.style = None + + def dispose(self): + # Reset the state attributes (to clear self-references) + self.states = [] + self.state = None + + def emit(self, event): + self.events.append(event) + while not self.need_more_events(): + self.event = self.events.pop(0) + self.state() + self.event = None + + # In some cases, we wait for a few next events before emitting. + + def need_more_events(self): + if not self.events: + return True + event = self.events[0] + if isinstance(event, DocumentStartEvent): + return self.need_events(1) + elif isinstance(event, SequenceStartEvent): + return self.need_events(2) + elif isinstance(event, MappingStartEvent): + return self.need_events(3) + else: + return False + + def need_events(self, count): + level = 0 + for event in self.events[1:]: + if isinstance(event, (DocumentStartEvent, CollectionStartEvent)): + level += 1 + elif isinstance(event, (DocumentEndEvent, CollectionEndEvent)): + level -= 1 + elif isinstance(event, StreamEndEvent): + level = -1 + if level < 0: + return False + return (len(self.events) < count+1) + + def increase_indent(self, flow=False, indentless=False): + self.indents.append(self.indent) + if self.indent is None: + if flow: + self.indent = self.best_indent + else: + self.indent = 0 + elif not indentless: + self.indent += self.best_indent + + # States. + + # Stream handlers. + + def expect_stream_start(self): + if isinstance(self.event, StreamStartEvent): + if self.event.encoding and not hasattr(self.stream, 'encoding'): + self.encoding = self.event.encoding + self.write_stream_start() + self.state = self.expect_first_document_start + else: + raise EmitterError("expected StreamStartEvent, but got %s" + % self.event) + + def expect_nothing(self): + raise EmitterError("expected nothing, but got %s" % self.event) + + # Document handlers. + + def expect_first_document_start(self): + return self.expect_document_start(first=True) + + def expect_document_start(self, first=False): + if isinstance(self.event, DocumentStartEvent): + if (self.event.version or self.event.tags) and self.open_ended: + self.write_indicator('...', True) + self.write_indent() + if self.event.version: + version_text = self.prepare_version(self.event.version) + self.write_version_directive(version_text) + self.tag_prefixes = self.DEFAULT_TAG_PREFIXES.copy() + if self.event.tags: + handles = sorted(self.event.tags.keys()) + for handle in handles: + prefix = self.event.tags[handle] + self.tag_prefixes[prefix] = handle + handle_text = self.prepare_tag_handle(handle) + prefix_text = self.prepare_tag_prefix(prefix) + self.write_tag_directive(handle_text, prefix_text) + implicit = (first and not self.event.explicit and not self.canonical + and not self.event.version and not self.event.tags + and not self.check_empty_document()) + if not implicit: + self.write_indent() + self.write_indicator('---', True) + if self.canonical: + self.write_indent() + self.state = self.expect_document_root + elif isinstance(self.event, StreamEndEvent): + if self.open_ended: + self.write_indicator('...', True) + self.write_indent() + self.write_stream_end() + self.state = self.expect_nothing + else: + raise EmitterError("expected DocumentStartEvent, but got %s" + % self.event) + + def expect_document_end(self): + if isinstance(self.event, DocumentEndEvent): + self.write_indent() + if self.event.explicit: + self.write_indicator('...', True) + self.write_indent() + self.flush_stream() + self.state = self.expect_document_start + else: + raise EmitterError("expected DocumentEndEvent, but got %s" + % self.event) + + def expect_document_root(self): + self.states.append(self.expect_document_end) + self.expect_node(root=True) + + # Node handlers. + + def expect_node(self, root=False, sequence=False, mapping=False, + simple_key=False): + self.root_context = root + self.sequence_context = sequence + self.mapping_context = mapping + self.simple_key_context = simple_key + if isinstance(self.event, AliasEvent): + self.expect_alias() + elif isinstance(self.event, (ScalarEvent, CollectionStartEvent)): + self.process_anchor('&') + self.process_tag() + if isinstance(self.event, ScalarEvent): + self.expect_scalar() + elif isinstance(self.event, SequenceStartEvent): + if self.flow_level or self.canonical or self.event.flow_style \ + or self.check_empty_sequence(): + self.expect_flow_sequence() + else: + self.expect_block_sequence() + elif isinstance(self.event, MappingStartEvent): + if self.flow_level or self.canonical or self.event.flow_style \ + or self.check_empty_mapping(): + self.expect_flow_mapping() + else: + self.expect_block_mapping() + else: + raise EmitterError("expected NodeEvent, but got %s" % self.event) + + def expect_alias(self): + if self.event.anchor is None: + raise EmitterError("anchor is not specified for alias") + self.process_anchor('*') + self.state = self.states.pop() + + def expect_scalar(self): + self.increase_indent(flow=True) + self.process_scalar() + self.indent = self.indents.pop() + self.state = self.states.pop() + + # Flow sequence handlers. + + def expect_flow_sequence(self): + self.write_indicator('[', True, whitespace=True) + self.flow_level += 1 + self.increase_indent(flow=True) + self.state = self.expect_first_flow_sequence_item + + def expect_first_flow_sequence_item(self): + if isinstance(self.event, SequenceEndEvent): + self.indent = self.indents.pop() + self.flow_level -= 1 + self.write_indicator(']', False) + self.state = self.states.pop() + else: + if self.canonical or self.column > self.best_width: + self.write_indent() + self.states.append(self.expect_flow_sequence_item) + self.expect_node(sequence=True) + + def expect_flow_sequence_item(self): + if isinstance(self.event, SequenceEndEvent): + self.indent = self.indents.pop() + self.flow_level -= 1 + if self.canonical: + self.write_indicator(',', False) + self.write_indent() + self.write_indicator(']', False) + self.state = self.states.pop() + else: + self.write_indicator(',', False) + if self.canonical or self.column > self.best_width: + self.write_indent() + self.states.append(self.expect_flow_sequence_item) + self.expect_node(sequence=True) + + # Flow mapping handlers. + + def expect_flow_mapping(self): + self.write_indicator('{', True, whitespace=True) + self.flow_level += 1 + self.increase_indent(flow=True) + self.state = self.expect_first_flow_mapping_key + + def expect_first_flow_mapping_key(self): + if isinstance(self.event, MappingEndEvent): + self.indent = self.indents.pop() + self.flow_level -= 1 + self.write_indicator('}', False) + self.state = self.states.pop() + else: + if self.canonical or self.column > self.best_width: + self.write_indent() + if not self.canonical and self.check_simple_key(): + self.states.append(self.expect_flow_mapping_simple_value) + self.expect_node(mapping=True, simple_key=True) + else: + self.write_indicator('?', True) + self.states.append(self.expect_flow_mapping_value) + self.expect_node(mapping=True) + + def expect_flow_mapping_key(self): + if isinstance(self.event, MappingEndEvent): + self.indent = self.indents.pop() + self.flow_level -= 1 + if self.canonical: + self.write_indicator(',', False) + self.write_indent() + self.write_indicator('}', False) + self.state = self.states.pop() + else: + self.write_indicator(',', False) + if self.canonical or self.column > self.best_width: + self.write_indent() + if not self.canonical and self.check_simple_key(): + self.states.append(self.expect_flow_mapping_simple_value) + self.expect_node(mapping=True, simple_key=True) + else: + self.write_indicator('?', True) + self.states.append(self.expect_flow_mapping_value) + self.expect_node(mapping=True) + + def expect_flow_mapping_simple_value(self): + self.write_indicator(':', False) + self.states.append(self.expect_flow_mapping_key) + self.expect_node(mapping=True) + + def expect_flow_mapping_value(self): + if self.canonical or self.column > self.best_width: + self.write_indent() + self.write_indicator(':', True) + self.states.append(self.expect_flow_mapping_key) + self.expect_node(mapping=True) + + # Block sequence handlers. + + def expect_block_sequence(self): + indentless = (self.mapping_context and not self.indention) + self.increase_indent(flow=False, indentless=indentless) + self.state = self.expect_first_block_sequence_item + + def expect_first_block_sequence_item(self): + return self.expect_block_sequence_item(first=True) + + def expect_block_sequence_item(self, first=False): + if not first and isinstance(self.event, SequenceEndEvent): + self.indent = self.indents.pop() + self.state = self.states.pop() + else: + self.write_indent() + self.write_indicator('-', True, indention=True) + self.states.append(self.expect_block_sequence_item) + self.expect_node(sequence=True) + + # Block mapping handlers. + + def expect_block_mapping(self): + self.increase_indent(flow=False) + self.state = self.expect_first_block_mapping_key + + def expect_first_block_mapping_key(self): + return self.expect_block_mapping_key(first=True) + + def expect_block_mapping_key(self, first=False): + if not first and isinstance(self.event, MappingEndEvent): + self.indent = self.indents.pop() + self.state = self.states.pop() + else: + self.write_indent() + if self.check_simple_key(): + self.states.append(self.expect_block_mapping_simple_value) + self.expect_node(mapping=True, simple_key=True) + else: + self.write_indicator('?', True, indention=True) + self.states.append(self.expect_block_mapping_value) + self.expect_node(mapping=True) + + def expect_block_mapping_simple_value(self): + self.write_indicator(':', False) + self.states.append(self.expect_block_mapping_key) + self.expect_node(mapping=True) + + def expect_block_mapping_value(self): + self.write_indent() + self.write_indicator(':', True, indention=True) + self.states.append(self.expect_block_mapping_key) + self.expect_node(mapping=True) + + # Checkers. + + def check_empty_sequence(self): + return (isinstance(self.event, SequenceStartEvent) and self.events + and isinstance(self.events[0], SequenceEndEvent)) + + def check_empty_mapping(self): + return (isinstance(self.event, MappingStartEvent) and self.events + and isinstance(self.events[0], MappingEndEvent)) + + def check_empty_document(self): + if not isinstance(self.event, DocumentStartEvent) or not self.events: + return False + event = self.events[0] + return (isinstance(event, ScalarEvent) and event.anchor is None + and event.tag is None and event.implicit and event.value == '') + + def check_simple_key(self): + length = 0 + if isinstance(self.event, NodeEvent) and self.event.anchor is not None: + if self.prepared_anchor is None: + self.prepared_anchor = self.prepare_anchor(self.event.anchor) + length += len(self.prepared_anchor) + if isinstance(self.event, (ScalarEvent, CollectionStartEvent)) \ + and self.event.tag is not None: + if self.prepared_tag is None: + self.prepared_tag = self.prepare_tag(self.event.tag) + length += len(self.prepared_tag) + if isinstance(self.event, ScalarEvent): + if self.analysis is None: + self.analysis = self.analyze_scalar(self.event.value) + length += len(self.analysis.scalar) + return (length < 128 and (isinstance(self.event, AliasEvent) + or (isinstance(self.event, ScalarEvent) + and not self.analysis.empty and not self.analysis.multiline) + or self.check_empty_sequence() or self.check_empty_mapping())) + + # Anchor, Tag, and Scalar processors. + + def process_anchor(self, indicator): + if self.event.anchor is None: + self.prepared_anchor = None + return + if self.prepared_anchor is None: + self.prepared_anchor = self.prepare_anchor(self.event.anchor) + if self.prepared_anchor: + self.write_indicator(indicator+self.prepared_anchor, True) + self.prepared_anchor = None + + def process_tag(self): + tag = self.event.tag + if isinstance(self.event, ScalarEvent): + if self.style is None: + self.style = self.choose_scalar_style() + if ((not self.canonical or tag is None) and + ((self.style == '' and self.event.implicit[0]) + or (self.style != '' and self.event.implicit[1]))): + self.prepared_tag = None + return + if self.event.implicit[0] and tag is None: + tag = '!' + self.prepared_tag = None + else: + if (not self.canonical or tag is None) and self.event.implicit: + self.prepared_tag = None + return + if tag is None: + raise EmitterError("tag is not specified") + if self.prepared_tag is None: + self.prepared_tag = self.prepare_tag(tag) + if self.prepared_tag: + self.write_indicator(self.prepared_tag, True) + self.prepared_tag = None + + def choose_scalar_style(self): + if self.analysis is None: + self.analysis = self.analyze_scalar(self.event.value) + if self.event.style == '"' or self.canonical: + return '"' + if not self.event.style and self.event.implicit[0]: + if (not (self.simple_key_context and + (self.analysis.empty or self.analysis.multiline)) + and (self.flow_level and self.analysis.allow_flow_plain + or (not self.flow_level and self.analysis.allow_block_plain))): + return '' + if self.event.style and self.event.style in '|>': + if (not self.flow_level and not self.simple_key_context + and self.analysis.allow_block): + return self.event.style + if not self.event.style or self.event.style == '\'': + if (self.analysis.allow_single_quoted and + not (self.simple_key_context and self.analysis.multiline)): + return '\'' + return '"' + + def process_scalar(self): + if self.analysis is None: + self.analysis = self.analyze_scalar(self.event.value) + if self.style is None: + self.style = self.choose_scalar_style() + split = (not self.simple_key_context) + #if self.analysis.multiline and split \ + # and (not self.style or self.style in '\'\"'): + # self.write_indent() + if self.style == '"': + self.write_double_quoted(self.analysis.scalar, split) + elif self.style == '\'': + self.write_single_quoted(self.analysis.scalar, split) + elif self.style == '>': + self.write_folded(self.analysis.scalar) + elif self.style == '|': + self.write_literal(self.analysis.scalar) + else: + self.write_plain(self.analysis.scalar, split) + self.analysis = None + self.style = None + + # Analyzers. + + def prepare_version(self, version): + major, minor = version + if major != 1: + raise EmitterError("unsupported YAML version: %d.%d" % (major, minor)) + return '%d.%d' % (major, minor) + + def prepare_tag_handle(self, handle): + if not handle: + raise EmitterError("tag handle must not be empty") + if handle[0] != '!' or handle[-1] != '!': + raise EmitterError("tag handle must start and end with '!': %r" % handle) + for ch in handle[1:-1]: + if not ('0' <= ch <= '9' or 'A' <= ch <= 'Z' or 'a' <= ch <= 'z' \ + or ch in '-_'): + raise EmitterError("invalid character %r in the tag handle: %r" + % (ch, handle)) + return handle + + def prepare_tag_prefix(self, prefix): + if not prefix: + raise EmitterError("tag prefix must not be empty") + chunks = [] + start = end = 0 + if prefix[0] == '!': + end = 1 + while end < len(prefix): + ch = prefix[end] + if '0' <= ch <= '9' or 'A' <= ch <= 'Z' or 'a' <= ch <= 'z' \ + or ch in '-;/?!:@&=+$,_.~*\'()[]': + end += 1 + else: + if start < end: + chunks.append(prefix[start:end]) + start = end = end+1 + data = ch.encode('utf-8') + for ch in data: + chunks.append('%%%02X' % ord(ch)) + if start < end: + chunks.append(prefix[start:end]) + return ''.join(chunks) + + def prepare_tag(self, tag): + if not tag: + raise EmitterError("tag must not be empty") + if tag == '!': + return tag + handle = None + suffix = tag + prefixes = sorted(self.tag_prefixes.keys()) + for prefix in prefixes: + if tag.startswith(prefix) \ + and (prefix == '!' or len(prefix) < len(tag)): + handle = self.tag_prefixes[prefix] + suffix = tag[len(prefix):] + chunks = [] + start = end = 0 + while end < len(suffix): + ch = suffix[end] + if '0' <= ch <= '9' or 'A' <= ch <= 'Z' or 'a' <= ch <= 'z' \ + or ch in '-;/?:@&=+$,_.~*\'()[]' \ + or (ch == '!' and handle != '!'): + end += 1 + else: + if start < end: + chunks.append(suffix[start:end]) + start = end = end+1 + data = ch.encode('utf-8') + for ch in data: + chunks.append('%%%02X' % ch) + if start < end: + chunks.append(suffix[start:end]) + suffix_text = ''.join(chunks) + if handle: + return '%s%s' % (handle, suffix_text) + else: + return '!<%s>' % suffix_text + + def prepare_anchor(self, anchor): + if not anchor: + raise EmitterError("anchor must not be empty") + for ch in anchor: + if not ('0' <= ch <= '9' or 'A' <= ch <= 'Z' or 'a' <= ch <= 'z' \ + or ch in '-_'): + raise EmitterError("invalid character %r in the anchor: %r" + % (ch, anchor)) + return anchor + + def analyze_scalar(self, scalar): + + # Empty scalar is a special case. + if not scalar: + return ScalarAnalysis(scalar=scalar, empty=True, multiline=False, + allow_flow_plain=False, allow_block_plain=True, + allow_single_quoted=True, allow_double_quoted=True, + allow_block=False) + + # Indicators and special characters. + block_indicators = False + flow_indicators = False + line_breaks = False + special_characters = False + + # Important whitespace combinations. + leading_space = False + leading_break = False + trailing_space = False + trailing_break = False + break_space = False + space_break = False + + # Check document indicators. + if scalar.startswith('---') or scalar.startswith('...'): + block_indicators = True + flow_indicators = True + + # First character or preceded by a whitespace. + preceded_by_whitespace = True + + # Last character or followed by a whitespace. + followed_by_whitespace = (len(scalar) == 1 or + scalar[1] in '\0 \t\r\n\x85\u2028\u2029') + + # The previous character is a space. + previous_space = False + + # The previous character is a break. + previous_break = False + + index = 0 + while index < len(scalar): + ch = scalar[index] + + # Check for indicators. + if index == 0: + # Leading indicators are special characters. + if ch in '#,[]{}&*!|>\'\"%@`': + flow_indicators = True + block_indicators = True + if ch in '?:': + flow_indicators = True + if followed_by_whitespace: + block_indicators = True + if ch == '-' and followed_by_whitespace: + flow_indicators = True + block_indicators = True + else: + # Some indicators cannot appear within a scalar as well. + if ch in ',?[]{}': + flow_indicators = True + if ch == ':': + flow_indicators = True + if followed_by_whitespace: + block_indicators = True + if ch == '#' and preceded_by_whitespace: + flow_indicators = True + block_indicators = True + + # Check for line breaks, special, and unicode characters. + if ch in '\n\x85\u2028\u2029': + line_breaks = True + if not (ch == '\n' or '\x20' <= ch <= '\x7E'): + if (ch == '\x85' or '\xA0' <= ch <= '\uD7FF' + or '\uE000' <= ch <= '\uFFFD' + or '\U00010000' <= ch < '\U0010ffff') and ch != '\uFEFF': + unicode_characters = True + if not self.allow_unicode: + special_characters = True + else: + special_characters = True + + # Detect important whitespace combinations. + if ch == ' ': + if index == 0: + leading_space = True + if index == len(scalar)-1: + trailing_space = True + if previous_break: + break_space = True + previous_space = True + previous_break = False + elif ch in '\n\x85\u2028\u2029': + if index == 0: + leading_break = True + if index == len(scalar)-1: + trailing_break = True + if previous_space: + space_break = True + previous_space = False + previous_break = True + else: + previous_space = False + previous_break = False + + # Prepare for the next character. + index += 1 + preceded_by_whitespace = (ch in '\0 \t\r\n\x85\u2028\u2029') + followed_by_whitespace = (index+1 >= len(scalar) or + scalar[index+1] in '\0 \t\r\n\x85\u2028\u2029') + + # Let's decide what styles are allowed. + allow_flow_plain = True + allow_block_plain = True + allow_single_quoted = True + allow_double_quoted = True + allow_block = True + + # Leading and trailing whitespaces are bad for plain scalars. + if (leading_space or leading_break + or trailing_space or trailing_break): + allow_flow_plain = allow_block_plain = False + + # We do not permit trailing spaces for block scalars. + if trailing_space: + allow_block = False + + # Spaces at the beginning of a new line are only acceptable for block + # scalars. + if break_space: + allow_flow_plain = allow_block_plain = allow_single_quoted = False + + # Spaces followed by breaks, as well as special character are only + # allowed for double quoted scalars. + if space_break or special_characters: + allow_flow_plain = allow_block_plain = \ + allow_single_quoted = allow_block = False + + # Although the plain scalar writer supports breaks, we never emit + # multiline plain scalars. + if line_breaks: + allow_flow_plain = allow_block_plain = False + + # Flow indicators are forbidden for flow plain scalars. + if flow_indicators: + allow_flow_plain = False + + # Block indicators are forbidden for block plain scalars. + if block_indicators: + allow_block_plain = False + + return ScalarAnalysis(scalar=scalar, + empty=False, multiline=line_breaks, + allow_flow_plain=allow_flow_plain, + allow_block_plain=allow_block_plain, + allow_single_quoted=allow_single_quoted, + allow_double_quoted=allow_double_quoted, + allow_block=allow_block) + + # Writers. + + def flush_stream(self): + if hasattr(self.stream, 'flush'): + self.stream.flush() + + def write_stream_start(self): + # Write BOM if needed. + if self.encoding and self.encoding.startswith('utf-16'): + self.stream.write('\uFEFF'.encode(self.encoding)) + + def write_stream_end(self): + self.flush_stream() + + def write_indicator(self, indicator, need_whitespace, + whitespace=False, indention=False): + if self.whitespace or not need_whitespace: + data = indicator + else: + data = ' '+indicator + self.whitespace = whitespace + self.indention = self.indention and indention + self.column += len(data) + self.open_ended = False + if self.encoding: + data = data.encode(self.encoding) + self.stream.write(data) + + def write_indent(self): + indent = self.indent or 0 + if not self.indention or self.column > indent \ + or (self.column == indent and not self.whitespace): + self.write_line_break() + if self.column < indent: + self.whitespace = True + data = ' '*(indent-self.column) + self.column = indent + if self.encoding: + data = data.encode(self.encoding) + self.stream.write(data) + + def write_line_break(self, data=None): + if data is None: + data = self.best_line_break + self.whitespace = True + self.indention = True + self.line += 1 + self.column = 0 + if self.encoding: + data = data.encode(self.encoding) + self.stream.write(data) + + def write_version_directive(self, version_text): + data = '%%YAML %s' % version_text + if self.encoding: + data = data.encode(self.encoding) + self.stream.write(data) + self.write_line_break() + + def write_tag_directive(self, handle_text, prefix_text): + data = '%%TAG %s %s' % (handle_text, prefix_text) + if self.encoding: + data = data.encode(self.encoding) + self.stream.write(data) + self.write_line_break() + + # Scalar streams. + + def write_single_quoted(self, text, split=True): + self.write_indicator('\'', True) + spaces = False + breaks = False + start = end = 0 + while end <= len(text): + ch = None + if end < len(text): + ch = text[end] + if spaces: + if ch is None or ch != ' ': + if start+1 == end and self.column > self.best_width and split \ + and start != 0 and end != len(text): + self.write_indent() + else: + data = text[start:end] + self.column += len(data) + if self.encoding: + data = data.encode(self.encoding) + self.stream.write(data) + start = end + elif breaks: + if ch is None or ch not in '\n\x85\u2028\u2029': + if text[start] == '\n': + self.write_line_break() + for br in text[start:end]: + if br == '\n': + self.write_line_break() + else: + self.write_line_break(br) + self.write_indent() + start = end + else: + if ch is None or ch in ' \n\x85\u2028\u2029' or ch == '\'': + if start < end: + data = text[start:end] + self.column += len(data) + if self.encoding: + data = data.encode(self.encoding) + self.stream.write(data) + start = end + if ch == '\'': + data = '\'\'' + self.column += 2 + if self.encoding: + data = data.encode(self.encoding) + self.stream.write(data) + start = end + 1 + if ch is not None: + spaces = (ch == ' ') + breaks = (ch in '\n\x85\u2028\u2029') + end += 1 + self.write_indicator('\'', False) + + ESCAPE_REPLACEMENTS = { + '\0': '0', + '\x07': 'a', + '\x08': 'b', + '\x09': 't', + '\x0A': 'n', + '\x0B': 'v', + '\x0C': 'f', + '\x0D': 'r', + '\x1B': 'e', + '\"': '\"', + '\\': '\\', + '\x85': 'N', + '\xA0': '_', + '\u2028': 'L', + '\u2029': 'P', + } + + def write_double_quoted(self, text, split=True): + self.write_indicator('"', True) + start = end = 0 + while end <= len(text): + ch = None + if end < len(text): + ch = text[end] + if ch is None or ch in '"\\\x85\u2028\u2029\uFEFF' \ + or not ('\x20' <= ch <= '\x7E' + or (self.allow_unicode + and ('\xA0' <= ch <= '\uD7FF' + or '\uE000' <= ch <= '\uFFFD'))): + if start < end: + data = text[start:end] + self.column += len(data) + if self.encoding: + data = data.encode(self.encoding) + self.stream.write(data) + start = end + if ch is not None: + if ch in self.ESCAPE_REPLACEMENTS: + data = '\\'+self.ESCAPE_REPLACEMENTS[ch] + elif ch <= '\xFF': + data = '\\x%02X' % ord(ch) + elif ch <= '\uFFFF': + data = '\\u%04X' % ord(ch) + else: + data = '\\U%08X' % ord(ch) + self.column += len(data) + if self.encoding: + data = data.encode(self.encoding) + self.stream.write(data) + start = end+1 + if 0 < end < len(text)-1 and (ch == ' ' or start >= end) \ + and self.column+(end-start) > self.best_width and split: + data = text[start:end]+'\\' + if start < end: + start = end + self.column += len(data) + if self.encoding: + data = data.encode(self.encoding) + self.stream.write(data) + self.write_indent() + self.whitespace = False + self.indention = False + if text[start] == ' ': + data = '\\' + self.column += len(data) + if self.encoding: + data = data.encode(self.encoding) + self.stream.write(data) + end += 1 + self.write_indicator('"', False) + + def determine_block_hints(self, text): + hints = '' + if text: + if text[0] in ' \n\x85\u2028\u2029': + hints += str(self.best_indent) + if text[-1] not in '\n\x85\u2028\u2029': + hints += '-' + elif len(text) == 1 or text[-2] in '\n\x85\u2028\u2029': + hints += '+' + return hints + + def write_folded(self, text): + hints = self.determine_block_hints(text) + self.write_indicator('>'+hints, True) + if hints[-1:] == '+': + self.open_ended = True + self.write_line_break() + leading_space = True + spaces = False + breaks = True + start = end = 0 + while end <= len(text): + ch = None + if end < len(text): + ch = text[end] + if breaks: + if ch is None or ch not in '\n\x85\u2028\u2029': + if not leading_space and ch is not None and ch != ' ' \ + and text[start] == '\n': + self.write_line_break() + leading_space = (ch == ' ') + for br in text[start:end]: + if br == '\n': + self.write_line_break() + else: + self.write_line_break(br) + if ch is not None: + self.write_indent() + start = end + elif spaces: + if ch != ' ': + if start+1 == end and self.column > self.best_width: + self.write_indent() + else: + data = text[start:end] + self.column += len(data) + if self.encoding: + data = data.encode(self.encoding) + self.stream.write(data) + start = end + else: + if ch is None or ch in ' \n\x85\u2028\u2029': + data = text[start:end] + self.column += len(data) + if self.encoding: + data = data.encode(self.encoding) + self.stream.write(data) + if ch is None: + self.write_line_break() + start = end + if ch is not None: + breaks = (ch in '\n\x85\u2028\u2029') + spaces = (ch == ' ') + end += 1 + + def write_literal(self, text): + hints = self.determine_block_hints(text) + self.write_indicator('|'+hints, True) + if hints[-1:] == '+': + self.open_ended = True + self.write_line_break() + breaks = True + start = end = 0 + while end <= len(text): + ch = None + if end < len(text): + ch = text[end] + if breaks: + if ch is None or ch not in '\n\x85\u2028\u2029': + for br in text[start:end]: + if br == '\n': + self.write_line_break() + else: + self.write_line_break(br) + if ch is not None: + self.write_indent() + start = end + else: + if ch is None or ch in '\n\x85\u2028\u2029': + data = text[start:end] + if self.encoding: + data = data.encode(self.encoding) + self.stream.write(data) + if ch is None: + self.write_line_break() + start = end + if ch is not None: + breaks = (ch in '\n\x85\u2028\u2029') + end += 1 + + def write_plain(self, text, split=True): + if self.root_context: + self.open_ended = True + if not text: + return + if not self.whitespace: + data = ' ' + self.column += len(data) + if self.encoding: + data = data.encode(self.encoding) + self.stream.write(data) + self.whitespace = False + self.indention = False + spaces = False + breaks = False + start = end = 0 + while end <= len(text): + ch = None + if end < len(text): + ch = text[end] + if spaces: + if ch != ' ': + if start+1 == end and self.column > self.best_width and split: + self.write_indent() + self.whitespace = False + self.indention = False + else: + data = text[start:end] + self.column += len(data) + if self.encoding: + data = data.encode(self.encoding) + self.stream.write(data) + start = end + elif breaks: + if ch not in '\n\x85\u2028\u2029': + if text[start] == '\n': + self.write_line_break() + for br in text[start:end]: + if br == '\n': + self.write_line_break() + else: + self.write_line_break(br) + self.write_indent() + self.whitespace = False + self.indention = False + start = end + else: + if ch is None or ch in ' \n\x85\u2028\u2029': + data = text[start:end] + self.column += len(data) + if self.encoding: + data = data.encode(self.encoding) + self.stream.write(data) + start = end + if ch is not None: + spaces = (ch == ' ') + breaks = (ch in '\n\x85\u2028\u2029') + end += 1 diff --git a/yaml/error.py b/yaml/error.py new file mode 100644 index 0000000..b796b4d --- /dev/null +++ b/yaml/error.py @@ -0,0 +1,75 @@ + +__all__ = ['Mark', 'YAMLError', 'MarkedYAMLError'] + +class Mark: + + def __init__(self, name, index, line, column, buffer, pointer): + self.name = name + self.index = index + self.line = line + self.column = column + self.buffer = buffer + self.pointer = pointer + + def get_snippet(self, indent=4, max_length=75): + if self.buffer is None: + return None + head = '' + start = self.pointer + while start > 0 and self.buffer[start-1] not in '\0\r\n\x85\u2028\u2029': + start -= 1 + if self.pointer-start > max_length/2-1: + head = ' ... ' + start += 5 + break + tail = '' + end = self.pointer + while end < len(self.buffer) and self.buffer[end] not in '\0\r\n\x85\u2028\u2029': + end += 1 + if end-self.pointer > max_length/2-1: + tail = ' ... ' + end -= 5 + break + snippet = self.buffer[start:end] + return ' '*indent + head + snippet + tail + '\n' \ + + ' '*(indent+self.pointer-start+len(head)) + '^' + + def __str__(self): + snippet = self.get_snippet() + where = " in \"%s\", line %d, column %d" \ + % (self.name, self.line+1, self.column+1) + if snippet is not None: + where += ":\n"+snippet + return where + +class YAMLError(Exception): + pass + +class MarkedYAMLError(YAMLError): + + def __init__(self, context=None, context_mark=None, + problem=None, problem_mark=None, note=None): + self.context = context + self.context_mark = context_mark + self.problem = problem + self.problem_mark = problem_mark + self.note = note + + def __str__(self): + lines = [] + if self.context is not None: + lines.append(self.context) + if self.context_mark is not None \ + and (self.problem is None or self.problem_mark is None + or self.context_mark.name != self.problem_mark.name + or self.context_mark.line != self.problem_mark.line + or self.context_mark.column != self.problem_mark.column): + lines.append(str(self.context_mark)) + if self.problem is not None: + lines.append(self.problem) + if self.problem_mark is not None: + lines.append(str(self.problem_mark)) + if self.note is not None: + lines.append(self.note) + return '\n'.join(lines) + diff --git a/yaml/events.py b/yaml/events.py new file mode 100644 index 0000000..f79ad38 --- /dev/null +++ b/yaml/events.py @@ -0,0 +1,86 @@ + +# Abstract classes. + +class Event(object): + def __init__(self, start_mark=None, end_mark=None): + self.start_mark = start_mark + self.end_mark = end_mark + def __repr__(self): + attributes = [key for key in ['anchor', 'tag', 'implicit', 'value'] + if hasattr(self, key)] + arguments = ', '.join(['%s=%r' % (key, getattr(self, key)) + for key in attributes]) + return '%s(%s)' % (self.__class__.__name__, arguments) + +class NodeEvent(Event): + def __init__(self, anchor, start_mark=None, end_mark=None): + self.anchor = anchor + self.start_mark = start_mark + self.end_mark = end_mark + +class CollectionStartEvent(NodeEvent): + def __init__(self, anchor, tag, implicit, start_mark=None, end_mark=None, + flow_style=None): + self.anchor = anchor + self.tag = tag + self.implicit = implicit + self.start_mark = start_mark + self.end_mark = end_mark + self.flow_style = flow_style + +class CollectionEndEvent(Event): + pass + +# Implementations. + +class StreamStartEvent(Event): + def __init__(self, start_mark=None, end_mark=None, encoding=None): + self.start_mark = start_mark + self.end_mark = end_mark + self.encoding = encoding + +class StreamEndEvent(Event): + pass + +class DocumentStartEvent(Event): + def __init__(self, start_mark=None, end_mark=None, + explicit=None, version=None, tags=None): + self.start_mark = start_mark + self.end_mark = end_mark + self.explicit = explicit + self.version = version + self.tags = tags + +class DocumentEndEvent(Event): + def __init__(self, start_mark=None, end_mark=None, + explicit=None): + self.start_mark = start_mark + self.end_mark = end_mark + self.explicit = explicit + +class AliasEvent(NodeEvent): + pass + +class ScalarEvent(NodeEvent): + def __init__(self, anchor, tag, implicit, value, + start_mark=None, end_mark=None, style=None): + self.anchor = anchor + self.tag = tag + self.implicit = implicit + self.value = value + self.start_mark = start_mark + self.end_mark = end_mark + self.style = style + +class SequenceStartEvent(CollectionStartEvent): + pass + +class SequenceEndEvent(CollectionEndEvent): + pass + +class MappingStartEvent(CollectionStartEvent): + pass + +class MappingEndEvent(CollectionEndEvent): + pass + diff --git a/yaml/loader.py b/yaml/loader.py new file mode 100644 index 0000000..e90c112 --- /dev/null +++ b/yaml/loader.py @@ -0,0 +1,63 @@ + +__all__ = ['BaseLoader', 'FullLoader', 'SafeLoader', 'Loader', 'UnsafeLoader'] + +from .reader import * +from .scanner import * +from .parser import * +from .composer import * +from .constructor import * +from .resolver import * + +class BaseLoader(Reader, Scanner, Parser, Composer, BaseConstructor, BaseResolver): + + def __init__(self, stream): + Reader.__init__(self, stream) + Scanner.__init__(self) + Parser.__init__(self) + Composer.__init__(self) + BaseConstructor.__init__(self) + BaseResolver.__init__(self) + +class FullLoader(Reader, Scanner, Parser, Composer, FullConstructor, Resolver): + + def __init__(self, stream): + Reader.__init__(self, stream) + Scanner.__init__(self) + Parser.__init__(self) + Composer.__init__(self) + FullConstructor.__init__(self) + Resolver.__init__(self) + +class SafeLoader(Reader, Scanner, Parser, Composer, SafeConstructor, Resolver): + + def __init__(self, stream): + Reader.__init__(self, stream) + Scanner.__init__(self) + Parser.__init__(self) + Composer.__init__(self) + SafeConstructor.__init__(self) + Resolver.__init__(self) + +class Loader(Reader, Scanner, Parser, Composer, Constructor, Resolver): + + def __init__(self, stream): + Reader.__init__(self, stream) + Scanner.__init__(self) + Parser.__init__(self) + Composer.__init__(self) + Constructor.__init__(self) + Resolver.__init__(self) + +# UnsafeLoader is the same as Loader (which is and was always unsafe on +# untrusted input). Use of either Loader or UnsafeLoader should be rare, since +# FullLoad should be able to load almost all YAML safely. Loader is left intact +# to ensure backwards compatibility. +class UnsafeLoader(Reader, Scanner, Parser, Composer, Constructor, Resolver): + + def __init__(self, stream): + Reader.__init__(self, stream) + Scanner.__init__(self) + Parser.__init__(self) + Composer.__init__(self) + Constructor.__init__(self) + Resolver.__init__(self) diff --git a/yaml/nodes.py b/yaml/nodes.py new file mode 100644 index 0000000..c4f070c --- /dev/null +++ b/yaml/nodes.py @@ -0,0 +1,49 @@ + +class Node(object): + def __init__(self, tag, value, start_mark, end_mark): + self.tag = tag + self.value = value + self.start_mark = start_mark + self.end_mark = end_mark + def __repr__(self): + value = self.value + #if isinstance(value, list): + # if len(value) == 0: + # value = '<empty>' + # elif len(value) == 1: + # value = '<1 item>' + # else: + # value = '<%d items>' % len(value) + #else: + # if len(value) > 75: + # value = repr(value[:70]+u' ... ') + # else: + # value = repr(value) + value = repr(value) + return '%s(tag=%r, value=%s)' % (self.__class__.__name__, self.tag, value) + +class ScalarNode(Node): + id = 'scalar' + def __init__(self, tag, value, + start_mark=None, end_mark=None, style=None): + self.tag = tag + self.value = value + self.start_mark = start_mark + self.end_mark = end_mark + self.style = style + +class CollectionNode(Node): + def __init__(self, tag, value, + start_mark=None, end_mark=None, flow_style=None): + self.tag = tag + self.value = value + self.start_mark = start_mark + self.end_mark = end_mark + self.flow_style = flow_style + +class SequenceNode(CollectionNode): + id = 'sequence' + +class MappingNode(CollectionNode): + id = 'mapping' + diff --git a/yaml/parser.py b/yaml/parser.py new file mode 100644 index 0000000..13a5995 --- /dev/null +++ b/yaml/parser.py @@ -0,0 +1,589 @@ + +# The following YAML grammar is LL(1) and is parsed by a recursive descent +# parser. +# +# stream ::= STREAM-START implicit_document? explicit_document* STREAM-END +# implicit_document ::= block_node DOCUMENT-END* +# explicit_document ::= DIRECTIVE* DOCUMENT-START block_node? DOCUMENT-END* +# block_node_or_indentless_sequence ::= +# ALIAS +# | properties (block_content | indentless_block_sequence)? +# | block_content +# | indentless_block_sequence +# block_node ::= ALIAS +# | properties block_content? +# | block_content +# flow_node ::= ALIAS +# | properties flow_content? +# | flow_content +# properties ::= TAG ANCHOR? | ANCHOR TAG? +# block_content ::= block_collection | flow_collection | SCALAR +# flow_content ::= flow_collection | SCALAR +# block_collection ::= block_sequence | block_mapping +# flow_collection ::= flow_sequence | flow_mapping +# block_sequence ::= BLOCK-SEQUENCE-START (BLOCK-ENTRY block_node?)* BLOCK-END +# indentless_sequence ::= (BLOCK-ENTRY block_node?)+ +# block_mapping ::= BLOCK-MAPPING_START +# ((KEY block_node_or_indentless_sequence?)? +# (VALUE block_node_or_indentless_sequence?)?)* +# BLOCK-END +# flow_sequence ::= FLOW-SEQUENCE-START +# (flow_sequence_entry FLOW-ENTRY)* +# flow_sequence_entry? +# FLOW-SEQUENCE-END +# flow_sequence_entry ::= flow_node | KEY flow_node? (VALUE flow_node?)? +# flow_mapping ::= FLOW-MAPPING-START +# (flow_mapping_entry FLOW-ENTRY)* +# flow_mapping_entry? +# FLOW-MAPPING-END +# flow_mapping_entry ::= flow_node | KEY flow_node? (VALUE flow_node?)? +# +# FIRST sets: +# +# stream: { STREAM-START } +# explicit_document: { DIRECTIVE DOCUMENT-START } +# implicit_document: FIRST(block_node) +# block_node: { ALIAS TAG ANCHOR SCALAR BLOCK-SEQUENCE-START BLOCK-MAPPING-START FLOW-SEQUENCE-START FLOW-MAPPING-START } +# flow_node: { ALIAS ANCHOR TAG SCALAR FLOW-SEQUENCE-START FLOW-MAPPING-START } +# block_content: { BLOCK-SEQUENCE-START BLOCK-MAPPING-START FLOW-SEQUENCE-START FLOW-MAPPING-START SCALAR } +# flow_content: { FLOW-SEQUENCE-START FLOW-MAPPING-START SCALAR } +# block_collection: { BLOCK-SEQUENCE-START BLOCK-MAPPING-START } +# flow_collection: { FLOW-SEQUENCE-START FLOW-MAPPING-START } +# block_sequence: { BLOCK-SEQUENCE-START } +# block_mapping: { BLOCK-MAPPING-START } +# block_node_or_indentless_sequence: { ALIAS ANCHOR TAG SCALAR BLOCK-SEQUENCE-START BLOCK-MAPPING-START FLOW-SEQUENCE-START FLOW-MAPPING-START BLOCK-ENTRY } +# indentless_sequence: { ENTRY } +# flow_collection: { FLOW-SEQUENCE-START FLOW-MAPPING-START } +# flow_sequence: { FLOW-SEQUENCE-START } +# flow_mapping: { FLOW-MAPPING-START } +# flow_sequence_entry: { ALIAS ANCHOR TAG SCALAR FLOW-SEQUENCE-START FLOW-MAPPING-START KEY } +# flow_mapping_entry: { ALIAS ANCHOR TAG SCALAR FLOW-SEQUENCE-START FLOW-MAPPING-START KEY } + +__all__ = ['Parser', 'ParserError'] + +from .error import MarkedYAMLError +from .tokens import * +from .events import * +from .scanner import * + +class ParserError(MarkedYAMLError): + pass + +class Parser: + # Since writing a recursive-descendant parser is a straightforward task, we + # do not give many comments here. + + DEFAULT_TAGS = { + '!': '!', + '!!': 'tag:yaml.org,2002:', + } + + def __init__(self): + self.current_event = None + self.yaml_version = None + self.tag_handles = {} + self.states = [] + self.marks = [] + self.state = self.parse_stream_start + + def dispose(self): + # Reset the state attributes (to clear self-references) + self.states = [] + self.state = None + + def check_event(self, *choices): + # Check the type of the next event. + if self.current_event is None: + if self.state: + self.current_event = self.state() + if self.current_event is not None: + if not choices: + return True + for choice in choices: + if isinstance(self.current_event, choice): + return True + return False + + def peek_event(self): + # Get the next event. + if self.current_event is None: + if self.state: + self.current_event = self.state() + return self.current_event + + def get_event(self): + # Get the next event and proceed further. + if self.current_event is None: + if self.state: + self.current_event = self.state() + value = self.current_event + self.current_event = None + return value + + # stream ::= STREAM-START implicit_document? explicit_document* STREAM-END + # implicit_document ::= block_node DOCUMENT-END* + # explicit_document ::= DIRECTIVE* DOCUMENT-START block_node? DOCUMENT-END* + + def parse_stream_start(self): + + # Parse the stream start. + token = self.get_token() + event = StreamStartEvent(token.start_mark, token.end_mark, + encoding=token.encoding) + + # Prepare the next state. + self.state = self.parse_implicit_document_start + + return event + + def parse_implicit_document_start(self): + + # Parse an implicit document. + if not self.check_token(DirectiveToken, DocumentStartToken, + StreamEndToken): + self.tag_handles = self.DEFAULT_TAGS + token = self.peek_token() + start_mark = end_mark = token.start_mark + event = DocumentStartEvent(start_mark, end_mark, + explicit=False) + + # Prepare the next state. + self.states.append(self.parse_document_end) + self.state = self.parse_block_node + + return event + + else: + return self.parse_document_start() + + def parse_document_start(self): + + # Parse any extra document end indicators. + while self.check_token(DocumentEndToken): + self.get_token() + + # Parse an explicit document. + if not self.check_token(StreamEndToken): + token = self.peek_token() + start_mark = token.start_mark + version, tags = self.process_directives() + if not self.check_token(DocumentStartToken): + raise ParserError(None, None, + "expected '<document start>', but found %r" + % self.peek_token().id, + self.peek_token().start_mark) + token = self.get_token() + end_mark = token.end_mark + event = DocumentStartEvent(start_mark, end_mark, + explicit=True, version=version, tags=tags) + self.states.append(self.parse_document_end) + self.state = self.parse_document_content + else: + # Parse the end of the stream. + token = self.get_token() + event = StreamEndEvent(token.start_mark, token.end_mark) + assert not self.states + assert not self.marks + self.state = None + return event + + def parse_document_end(self): + + # Parse the document end. + token = self.peek_token() + start_mark = end_mark = token.start_mark + explicit = False + if self.check_token(DocumentEndToken): + token = self.get_token() + end_mark = token.end_mark + explicit = True + event = DocumentEndEvent(start_mark, end_mark, + explicit=explicit) + + # Prepare the next state. + self.state = self.parse_document_start + + return event + + def parse_document_content(self): + if self.check_token(DirectiveToken, + DocumentStartToken, DocumentEndToken, StreamEndToken): + event = self.process_empty_scalar(self.peek_token().start_mark) + self.state = self.states.pop() + return event + else: + return self.parse_block_node() + + def process_directives(self): + self.yaml_version = None + self.tag_handles = {} + while self.check_token(DirectiveToken): + token = self.get_token() + if token.name == 'YAML': + if self.yaml_version is not None: + raise ParserError(None, None, + "found duplicate YAML directive", token.start_mark) + major, minor = token.value + if major != 1: + raise ParserError(None, None, + "found incompatible YAML document (version 1.* is required)", + token.start_mark) + self.yaml_version = token.value + elif token.name == 'TAG': + handle, prefix = token.value + if handle in self.tag_handles: + raise ParserError(None, None, + "duplicate tag handle %r" % handle, + token.start_mark) + self.tag_handles[handle] = prefix + if self.tag_handles: + value = self.yaml_version, self.tag_handles.copy() + else: + value = self.yaml_version, None + for key in self.DEFAULT_TAGS: + if key not in self.tag_handles: + self.tag_handles[key] = self.DEFAULT_TAGS[key] + return value + + # block_node_or_indentless_sequence ::= ALIAS + # | properties (block_content | indentless_block_sequence)? + # | block_content + # | indentless_block_sequence + # block_node ::= ALIAS + # | properties block_content? + # | block_content + # flow_node ::= ALIAS + # | properties flow_content? + # | flow_content + # properties ::= TAG ANCHOR? | ANCHOR TAG? + # block_content ::= block_collection | flow_collection | SCALAR + # flow_content ::= flow_collection | SCALAR + # block_collection ::= block_sequence | block_mapping + # flow_collection ::= flow_sequence | flow_mapping + + def parse_block_node(self): + return self.parse_node(block=True) + + def parse_flow_node(self): + return self.parse_node() + + def parse_block_node_or_indentless_sequence(self): + return self.parse_node(block=True, indentless_sequence=True) + + def parse_node(self, block=False, indentless_sequence=False): + if self.check_token(AliasToken): + token = self.get_token() + event = AliasEvent(token.value, token.start_mark, token.end_mark) + self.state = self.states.pop() + else: + anchor = None + tag = None + start_mark = end_mark = tag_mark = None + if self.check_token(AnchorToken): + token = self.get_token() + start_mark = token.start_mark + end_mark = token.end_mark + anchor = token.value + if self.check_token(TagToken): + token = self.get_token() + tag_mark = token.start_mark + end_mark = token.end_mark + tag = token.value + elif self.check_token(TagToken): + token = self.get_token() + start_mark = tag_mark = token.start_mark + end_mark = token.end_mark + tag = token.value + if self.check_token(AnchorToken): + token = self.get_token() + end_mark = token.end_mark + anchor = token.value + if tag is not None: + handle, suffix = tag + if handle is not None: + if handle not in self.tag_handles: + raise ParserError("while parsing a node", start_mark, + "found undefined tag handle %r" % handle, + tag_mark) + tag = self.tag_handles[handle]+suffix + else: + tag = suffix + #if tag == '!': + # raise ParserError("while parsing a node", start_mark, + # "found non-specific tag '!'", tag_mark, + # "Please check 'http://pyyaml.org/wiki/YAMLNonSpecificTag' and share your opinion.") + if start_mark is None: + start_mark = end_mark = self.peek_token().start_mark + event = None + implicit = (tag is None or tag == '!') + if indentless_sequence and self.check_token(BlockEntryToken): + end_mark = self.peek_token().end_mark + event = SequenceStartEvent(anchor, tag, implicit, + start_mark, end_mark) + self.state = self.parse_indentless_sequence_entry + else: + if self.check_token(ScalarToken): + token = self.get_token() + end_mark = token.end_mark + if (token.plain and tag is None) or tag == '!': + implicit = (True, False) + elif tag is None: + implicit = (False, True) + else: + implicit = (False, False) + event = ScalarEvent(anchor, tag, implicit, token.value, + start_mark, end_mark, style=token.style) + self.state = self.states.pop() + elif self.check_token(FlowSequenceStartToken): + end_mark = self.peek_token().end_mark + event = SequenceStartEvent(anchor, tag, implicit, + start_mark, end_mark, flow_style=True) + self.state = self.parse_flow_sequence_first_entry + elif self.check_token(FlowMappingStartToken): + end_mark = self.peek_token().end_mark + event = MappingStartEvent(anchor, tag, implicit, + start_mark, end_mark, flow_style=True) + self.state = self.parse_flow_mapping_first_key + elif block and self.check_token(BlockSequenceStartToken): + end_mark = self.peek_token().start_mark + event = SequenceStartEvent(anchor, tag, implicit, + start_mark, end_mark, flow_style=False) + self.state = self.parse_block_sequence_first_entry + elif block and self.check_token(BlockMappingStartToken): + end_mark = self.peek_token().start_mark + event = MappingStartEvent(anchor, tag, implicit, + start_mark, end_mark, flow_style=False) + self.state = self.parse_block_mapping_first_key + elif anchor is not None or tag is not None: + # Empty scalars are allowed even if a tag or an anchor is + # specified. + event = ScalarEvent(anchor, tag, (implicit, False), '', + start_mark, end_mark) + self.state = self.states.pop() + else: + if block: + node = 'block' + else: + node = 'flow' + token = self.peek_token() + raise ParserError("while parsing a %s node" % node, start_mark, + "expected the node content, but found %r" % token.id, + token.start_mark) + return event + + # block_sequence ::= BLOCK-SEQUENCE-START (BLOCK-ENTRY block_node?)* BLOCK-END + + def parse_block_sequence_first_entry(self): + token = self.get_token() + self.marks.append(token.start_mark) + return self.parse_block_sequence_entry() + + def parse_block_sequence_entry(self): + if self.check_token(BlockEntryToken): + token = self.get_token() + if not self.check_token(BlockEntryToken, BlockEndToken): + self.states.append(self.parse_block_sequence_entry) + return self.parse_block_node() + else: + self.state = self.parse_block_sequence_entry + return self.process_empty_scalar(token.end_mark) + if not self.check_token(BlockEndToken): + token = self.peek_token() + raise ParserError("while parsing a block collection", self.marks[-1], + "expected <block end>, but found %r" % token.id, token.start_mark) + token = self.get_token() + event = SequenceEndEvent(token.start_mark, token.end_mark) + self.state = self.states.pop() + self.marks.pop() + return event + + # indentless_sequence ::= (BLOCK-ENTRY block_node?)+ + + def parse_indentless_sequence_entry(self): + if self.check_token(BlockEntryToken): + token = self.get_token() + if not self.check_token(BlockEntryToken, + KeyToken, ValueToken, BlockEndToken): + self.states.append(self.parse_indentless_sequence_entry) + return self.parse_block_node() + else: + self.state = self.parse_indentless_sequence_entry + return self.process_empty_scalar(token.end_mark) + token = self.peek_token() + event = SequenceEndEvent(token.start_mark, token.start_mark) + self.state = self.states.pop() + return event + + # block_mapping ::= BLOCK-MAPPING_START + # ((KEY block_node_or_indentless_sequence?)? + # (VALUE block_node_or_indentless_sequence?)?)* + # BLOCK-END + + def parse_block_mapping_first_key(self): + token = self.get_token() + self.marks.append(token.start_mark) + return self.parse_block_mapping_key() + + def parse_block_mapping_key(self): + if self.check_token(KeyToken): + token = self.get_token() + if not self.check_token(KeyToken, ValueToken, BlockEndToken): + self.states.append(self.parse_block_mapping_value) + return self.parse_block_node_or_indentless_sequence() + else: + self.state = self.parse_block_mapping_value + return self.process_empty_scalar(token.end_mark) + if not self.check_token(BlockEndToken): + token = self.peek_token() + raise ParserError("while parsing a block mapping", self.marks[-1], + "expected <block end>, but found %r" % token.id, token.start_mark) + token = self.get_token() + event = MappingEndEvent(token.start_mark, token.end_mark) + self.state = self.states.pop() + self.marks.pop() + return event + + def parse_block_mapping_value(self): + if self.check_token(ValueToken): + token = self.get_token() + if not self.check_token(KeyToken, ValueToken, BlockEndToken): + self.states.append(self.parse_block_mapping_key) + return self.parse_block_node_or_indentless_sequence() + else: + self.state = self.parse_block_mapping_key + return self.process_empty_scalar(token.end_mark) + else: + self.state = self.parse_block_mapping_key + token = self.peek_token() + return self.process_empty_scalar(token.start_mark) + + # flow_sequence ::= FLOW-SEQUENCE-START + # (flow_sequence_entry FLOW-ENTRY)* + # flow_sequence_entry? + # FLOW-SEQUENCE-END + # flow_sequence_entry ::= flow_node | KEY flow_node? (VALUE flow_node?)? + # + # Note that while production rules for both flow_sequence_entry and + # flow_mapping_entry are equal, their interpretations are different. + # For `flow_sequence_entry`, the part `KEY flow_node? (VALUE flow_node?)?` + # generate an inline mapping (set syntax). + + def parse_flow_sequence_first_entry(self): + token = self.get_token() + self.marks.append(token.start_mark) + return self.parse_flow_sequence_entry(first=True) + + def parse_flow_sequence_entry(self, first=False): + if not self.check_token(FlowSequenceEndToken): + if not first: + if self.check_token(FlowEntryToken): + self.get_token() + else: + token = self.peek_token() + raise ParserError("while parsing a flow sequence", self.marks[-1], + "expected ',' or ']', but got %r" % token.id, token.start_mark) + + if self.check_token(KeyToken): + token = self.peek_token() + event = MappingStartEvent(None, None, True, + token.start_mark, token.end_mark, + flow_style=True) + self.state = self.parse_flow_sequence_entry_mapping_key + return event + elif not self.check_token(FlowSequenceEndToken): + self.states.append(self.parse_flow_sequence_entry) + return self.parse_flow_node() + token = self.get_token() + event = SequenceEndEvent(token.start_mark, token.end_mark) + self.state = self.states.pop() + self.marks.pop() + return event + + def parse_flow_sequence_entry_mapping_key(self): + token = self.get_token() + if not self.check_token(ValueToken, + FlowEntryToken, FlowSequenceEndToken): + self.states.append(self.parse_flow_sequence_entry_mapping_value) + return self.parse_flow_node() + else: + self.state = self.parse_flow_sequence_entry_mapping_value + return self.process_empty_scalar(token.end_mark) + + def parse_flow_sequence_entry_mapping_value(self): + if self.check_token(ValueToken): + token = self.get_token() + if not self.check_token(FlowEntryToken, FlowSequenceEndToken): + self.states.append(self.parse_flow_sequence_entry_mapping_end) + return self.parse_flow_node() + else: + self.state = self.parse_flow_sequence_entry_mapping_end + return self.process_empty_scalar(token.end_mark) + else: + self.state = self.parse_flow_sequence_entry_mapping_end + token = self.peek_token() + return self.process_empty_scalar(token.start_mark) + + def parse_flow_sequence_entry_mapping_end(self): + self.state = self.parse_flow_sequence_entry + token = self.peek_token() + return MappingEndEvent(token.start_mark, token.start_mark) + + # flow_mapping ::= FLOW-MAPPING-START + # (flow_mapping_entry FLOW-ENTRY)* + # flow_mapping_entry? + # FLOW-MAPPING-END + # flow_mapping_entry ::= flow_node | KEY flow_node? (VALUE flow_node?)? + + def parse_flow_mapping_first_key(self): + token = self.get_token() + self.marks.append(token.start_mark) + return self.parse_flow_mapping_key(first=True) + + def parse_flow_mapping_key(self, first=False): + if not self.check_token(FlowMappingEndToken): + if not first: + if self.check_token(FlowEntryToken): + self.get_token() + else: + token = self.peek_token() + raise ParserError("while parsing a flow mapping", self.marks[-1], + "expected ',' or '}', but got %r" % token.id, token.start_mark) + if self.check_token(KeyToken): + token = self.get_token() + if not self.check_token(ValueToken, + FlowEntryToken, FlowMappingEndToken): + self.states.append(self.parse_flow_mapping_value) + return self.parse_flow_node() + else: + self.state = self.parse_flow_mapping_value + return self.process_empty_scalar(token.end_mark) + elif not self.check_token(FlowMappingEndToken): + self.states.append(self.parse_flow_mapping_empty_value) + return self.parse_flow_node() + token = self.get_token() + event = MappingEndEvent(token.start_mark, token.end_mark) + self.state = self.states.pop() + self.marks.pop() + return event + + def parse_flow_mapping_value(self): + if self.check_token(ValueToken): + token = self.get_token() + if not self.check_token(FlowEntryToken, FlowMappingEndToken): + self.states.append(self.parse_flow_mapping_key) + return self.parse_flow_node() + else: + self.state = self.parse_flow_mapping_key + return self.process_empty_scalar(token.end_mark) + else: + self.state = self.parse_flow_mapping_key + token = self.peek_token() + return self.process_empty_scalar(token.start_mark) + + def parse_flow_mapping_empty_value(self): + self.state = self.parse_flow_mapping_key + return self.process_empty_scalar(self.peek_token().start_mark) + + def process_empty_scalar(self, mark): + return ScalarEvent(None, None, (True, False), '', mark, mark) + diff --git a/yaml/reader.py b/yaml/reader.py new file mode 100644 index 0000000..774b021 --- /dev/null +++ b/yaml/reader.py @@ -0,0 +1,185 @@ +# This module contains abstractions for the input stream. You don't have to +# looks further, there are no pretty code. +# +# We define two classes here. +# +# Mark(source, line, column) +# It's just a record and its only use is producing nice error messages. +# Parser does not use it for any other purposes. +# +# Reader(source, data) +# Reader determines the encoding of `data` and converts it to unicode. +# Reader provides the following methods and attributes: +# reader.peek(length=1) - return the next `length` characters +# reader.forward(length=1) - move the current position to `length` characters. +# reader.index - the number of the current character. +# reader.line, stream.column - the line and the column of the current character. + +__all__ = ['Reader', 'ReaderError'] + +from .error import YAMLError, Mark + +import codecs, re + +class ReaderError(YAMLError): + + def __init__(self, name, position, character, encoding, reason): + self.name = name + self.character = character + self.position = position + self.encoding = encoding + self.reason = reason + + def __str__(self): + if isinstance(self.character, bytes): + return "'%s' codec can't decode byte #x%02x: %s\n" \ + " in \"%s\", position %d" \ + % (self.encoding, ord(self.character), self.reason, + self.name, self.position) + else: + return "unacceptable character #x%04x: %s\n" \ + " in \"%s\", position %d" \ + % (self.character, self.reason, + self.name, self.position) + +class Reader(object): + # Reader: + # - determines the data encoding and converts it to a unicode string, + # - checks if characters are in allowed range, + # - adds '\0' to the end. + + # Reader accepts + # - a `bytes` object, + # - a `str` object, + # - a file-like object with its `read` method returning `str`, + # - a file-like object with its `read` method returning `unicode`. + + # Yeah, it's ugly and slow. + + def __init__(self, stream): + self.name = None + self.stream = None + self.stream_pointer = 0 + self.eof = True + self.buffer = '' + self.pointer = 0 + self.raw_buffer = None + self.raw_decode = None + self.encoding = None + self.index = 0 + self.line = 0 + self.column = 0 + if isinstance(stream, str): + self.name = "<unicode string>" + self.check_printable(stream) + self.buffer = stream+'\0' + elif isinstance(stream, bytes): + self.name = "<byte string>" + self.raw_buffer = stream + self.determine_encoding() + else: + self.stream = stream + self.name = getattr(stream, 'name', "<file>") + self.eof = False + self.raw_buffer = None + self.determine_encoding() + + def peek(self, index=0): + try: + return self.buffer[self.pointer+index] + except IndexError: + self.update(index+1) + return self.buffer[self.pointer+index] + + def prefix(self, length=1): + if self.pointer+length >= len(self.buffer): + self.update(length) + return self.buffer[self.pointer:self.pointer+length] + + def forward(self, length=1): + if self.pointer+length+1 >= len(self.buffer): + self.update(length+1) + while length: + ch = self.buffer[self.pointer] + self.pointer += 1 + self.index += 1 + if ch in '\n\x85\u2028\u2029' \ + or (ch == '\r' and self.buffer[self.pointer] != '\n'): + self.line += 1 + self.column = 0 + elif ch != '\uFEFF': + self.column += 1 + length -= 1 + + def get_mark(self): + if self.stream is None: + return Mark(self.name, self.index, self.line, self.column, + self.buffer, self.pointer) + else: + return Mark(self.name, self.index, self.line, self.column, + None, None) + + def determine_encoding(self): + while not self.eof and (self.raw_buffer is None or len(self.raw_buffer) < 2): + self.update_raw() + if isinstance(self.raw_buffer, bytes): + if self.raw_buffer.startswith(codecs.BOM_UTF16_LE): + self.raw_decode = codecs.utf_16_le_decode + self.encoding = 'utf-16-le' + elif self.raw_buffer.startswith(codecs.BOM_UTF16_BE): + self.raw_decode = codecs.utf_16_be_decode + self.encoding = 'utf-16-be' + else: + self.raw_decode = codecs.utf_8_decode + self.encoding = 'utf-8' + self.update(1) + + NON_PRINTABLE = re.compile('[^\x09\x0A\x0D\x20-\x7E\x85\xA0-\uD7FF\uE000-\uFFFD\U00010000-\U0010ffff]') + def check_printable(self, data): + match = self.NON_PRINTABLE.search(data) + if match: + character = match.group() + position = self.index+(len(self.buffer)-self.pointer)+match.start() + raise ReaderError(self.name, position, ord(character), + 'unicode', "special characters are not allowed") + + def update(self, length): + if self.raw_buffer is None: + return + self.buffer = self.buffer[self.pointer:] + self.pointer = 0 + while len(self.buffer) < length: + if not self.eof: + self.update_raw() + if self.raw_decode is not None: + try: + data, converted = self.raw_decode(self.raw_buffer, + 'strict', self.eof) + except UnicodeDecodeError as exc: + character = self.raw_buffer[exc.start] + if self.stream is not None: + position = self.stream_pointer-len(self.raw_buffer)+exc.start + else: + position = exc.start + raise ReaderError(self.name, position, character, + exc.encoding, exc.reason) + else: + data = self.raw_buffer + converted = len(data) + self.check_printable(data) + self.buffer += data + self.raw_buffer = self.raw_buffer[converted:] + if self.eof: + self.buffer += '\0' + self.raw_buffer = None + break + + def update_raw(self, size=4096): + data = self.stream.read(size) + if self.raw_buffer is None: + self.raw_buffer = data + else: + self.raw_buffer += data + self.stream_pointer += len(data) + if not data: + self.eof = True diff --git a/yaml/representer.py b/yaml/representer.py new file mode 100644 index 0000000..3b0b192 --- /dev/null +++ b/yaml/representer.py @@ -0,0 +1,389 @@ + +__all__ = ['BaseRepresenter', 'SafeRepresenter', 'Representer', + 'RepresenterError'] + +from .error import * +from .nodes import * + +import datetime, copyreg, types, base64, collections + +class RepresenterError(YAMLError): + pass + +class BaseRepresenter: + + yaml_representers = {} + yaml_multi_representers = {} + + def __init__(self, default_style=None, default_flow_style=False, sort_keys=True): + self.default_style = default_style + self.sort_keys = sort_keys + self.default_flow_style = default_flow_style + self.represented_objects = {} + self.object_keeper = [] + self.alias_key = None + + def represent(self, data): + node = self.represent_data(data) + self.serialize(node) + self.represented_objects = {} + self.object_keeper = [] + self.alias_key = None + + def represent_data(self, data): + if self.ignore_aliases(data): + self.alias_key = None + else: + self.alias_key = id(data) + if self.alias_key is not None: + if self.alias_key in self.represented_objects: + node = self.represented_objects[self.alias_key] + #if node is None: + # raise RepresenterError("recursive objects are not allowed: %r" % data) + return node + #self.represented_objects[alias_key] = None + self.object_keeper.append(data) + data_types = type(data).__mro__ + if data_types[0] in self.yaml_representers: + node = self.yaml_representers[data_types[0]](self, data) + else: + for data_type in data_types: + if data_type in self.yaml_multi_representers: + node = self.yaml_multi_representers[data_type](self, data) + break + else: + if None in self.yaml_multi_representers: + node = self.yaml_multi_representers[None](self, data) + elif None in self.yaml_representers: + node = self.yaml_representers[None](self, data) + else: + node = ScalarNode(None, str(data)) + #if alias_key is not None: + # self.represented_objects[alias_key] = node + return node + + @classmethod + def add_representer(cls, data_type, representer): + if not 'yaml_representers' in cls.__dict__: + cls.yaml_representers = cls.yaml_representers.copy() + cls.yaml_representers[data_type] = representer + + @classmethod + def add_multi_representer(cls, data_type, representer): + if not 'yaml_multi_representers' in cls.__dict__: + cls.yaml_multi_representers = cls.yaml_multi_representers.copy() + cls.yaml_multi_representers[data_type] = representer + + def represent_scalar(self, tag, value, style=None): + if style is None: + style = self.default_style + node = ScalarNode(tag, value, style=style) + if self.alias_key is not None: + self.represented_objects[self.alias_key] = node + return node + + def represent_sequence(self, tag, sequence, flow_style=None): + value = [] + node = SequenceNode(tag, value, flow_style=flow_style) + if self.alias_key is not None: + self.represented_objects[self.alias_key] = node + best_style = True + for item in sequence: + node_item = self.represent_data(item) + if not (isinstance(node_item, ScalarNode) and not node_item.style): + best_style = False + value.append(node_item) + if flow_style is None: + if self.default_flow_style is not None: + node.flow_style = self.default_flow_style + else: + node.flow_style = best_style + return node + + def represent_mapping(self, tag, mapping, flow_style=None): + value = [] + node = MappingNode(tag, value, flow_style=flow_style) + if self.alias_key is not None: + self.represented_objects[self.alias_key] = node + best_style = True + if hasattr(mapping, 'items'): + mapping = list(mapping.items()) + if self.sort_keys: + try: + mapping = sorted(mapping) + except TypeError: + pass + for item_key, item_value in mapping: + node_key = self.represent_data(item_key) + node_value = self.represent_data(item_value) + if not (isinstance(node_key, ScalarNode) and not node_key.style): + best_style = False + if not (isinstance(node_value, ScalarNode) and not node_value.style): + best_style = False + value.append((node_key, node_value)) + if flow_style is None: + if self.default_flow_style is not None: + node.flow_style = self.default_flow_style + else: + node.flow_style = best_style + return node + + def ignore_aliases(self, data): + return False + +class SafeRepresenter(BaseRepresenter): + + def ignore_aliases(self, data): + if data is None: + return True + if isinstance(data, tuple) and data == (): + return True + if isinstance(data, (str, bytes, bool, int, float)): + return True + + def represent_none(self, data): + return self.represent_scalar('tag:yaml.org,2002:null', 'null') + + def represent_str(self, data): + return self.represent_scalar('tag:yaml.org,2002:str', data) + + def represent_binary(self, data): + if hasattr(base64, 'encodebytes'): + data = base64.encodebytes(data).decode('ascii') + else: + data = base64.encodestring(data).decode('ascii') + return self.represent_scalar('tag:yaml.org,2002:binary', data, style='|') + + def represent_bool(self, data): + if data: + value = 'true' + else: + value = 'false' + return self.represent_scalar('tag:yaml.org,2002:bool', value) + + def represent_int(self, data): + return self.represent_scalar('tag:yaml.org,2002:int', str(data)) + + inf_value = 1e300 + while repr(inf_value) != repr(inf_value*inf_value): + inf_value *= inf_value + + def represent_float(self, data): + if data != data or (data == 0.0 and data == 1.0): + value = '.nan' + elif data == self.inf_value: + value = '.inf' + elif data == -self.inf_value: + value = '-.inf' + else: + value = repr(data).lower() + # Note that in some cases `repr(data)` represents a float number + # without the decimal parts. For instance: + # >>> repr(1e17) + # '1e17' + # Unfortunately, this is not a valid float representation according + # to the definition of the `!!float` tag. We fix this by adding + # '.0' before the 'e' symbol. + if '.' not in value and 'e' in value: + value = value.replace('e', '.0e', 1) + return self.represent_scalar('tag:yaml.org,2002:float', value) + + def represent_list(self, data): + #pairs = (len(data) > 0 and isinstance(data, list)) + #if pairs: + # for item in data: + # if not isinstance(item, tuple) or len(item) != 2: + # pairs = False + # break + #if not pairs: + return self.represent_sequence('tag:yaml.org,2002:seq', data) + #value = [] + #for item_key, item_value in data: + # value.append(self.represent_mapping(u'tag:yaml.org,2002:map', + # [(item_key, item_value)])) + #return SequenceNode(u'tag:yaml.org,2002:pairs', value) + + def represent_dict(self, data): + return self.represent_mapping('tag:yaml.org,2002:map', data) + + def represent_set(self, data): + value = {} + for key in data: + value[key] = None + return self.represent_mapping('tag:yaml.org,2002:set', value) + + def represent_date(self, data): + value = data.isoformat() + return self.represent_scalar('tag:yaml.org,2002:timestamp', value) + + def represent_datetime(self, data): + value = data.isoformat(' ') + return self.represent_scalar('tag:yaml.org,2002:timestamp', value) + + def represent_yaml_object(self, tag, data, cls, flow_style=None): + if hasattr(data, '__getstate__'): + state = data.__getstate__() + else: + state = data.__dict__.copy() + return self.represent_mapping(tag, state, flow_style=flow_style) + + def represent_undefined(self, data): + raise RepresenterError("cannot represent an object", data) + +SafeRepresenter.add_representer(type(None), + SafeRepresenter.represent_none) + +SafeRepresenter.add_representer(str, + SafeRepresenter.represent_str) + +SafeRepresenter.add_representer(bytes, + SafeRepresenter.represent_binary) + +SafeRepresenter.add_representer(bool, + SafeRepresenter.represent_bool) + +SafeRepresenter.add_representer(int, + SafeRepresenter.represent_int) + +SafeRepresenter.add_representer(float, + SafeRepresenter.represent_float) + +SafeRepresenter.add_representer(list, + SafeRepresenter.represent_list) + +SafeRepresenter.add_representer(tuple, + SafeRepresenter.represent_list) + +SafeRepresenter.add_representer(dict, + SafeRepresenter.represent_dict) + +SafeRepresenter.add_representer(set, + SafeRepresenter.represent_set) + +SafeRepresenter.add_representer(datetime.date, + SafeRepresenter.represent_date) + +SafeRepresenter.add_representer(datetime.datetime, + SafeRepresenter.represent_datetime) + +SafeRepresenter.add_representer(None, + SafeRepresenter.represent_undefined) + +class Representer(SafeRepresenter): + + def represent_complex(self, data): + if data.imag == 0.0: + data = '%r' % data.real + elif data.real == 0.0: + data = '%rj' % data.imag + elif data.imag > 0: + data = '%r+%rj' % (data.real, data.imag) + else: + data = '%r%rj' % (data.real, data.imag) + return self.represent_scalar('tag:yaml.org,2002:python/complex', data) + + def represent_tuple(self, data): + return self.represent_sequence('tag:yaml.org,2002:python/tuple', data) + + def represent_name(self, data): + name = '%s.%s' % (data.__module__, data.__name__) + return self.represent_scalar('tag:yaml.org,2002:python/name:'+name, '') + + def represent_module(self, data): + return self.represent_scalar( + 'tag:yaml.org,2002:python/module:'+data.__name__, '') + + def represent_object(self, data): + # We use __reduce__ API to save the data. data.__reduce__ returns + # a tuple of length 2-5: + # (function, args, state, listitems, dictitems) + + # For reconstructing, we calls function(*args), then set its state, + # listitems, and dictitems if they are not None. + + # A special case is when function.__name__ == '__newobj__'. In this + # case we create the object with args[0].__new__(*args). + + # Another special case is when __reduce__ returns a string - we don't + # support it. + + # We produce a !!python/object, !!python/object/new or + # !!python/object/apply node. + + cls = type(data) + if cls in copyreg.dispatch_table: + reduce = copyreg.dispatch_table[cls](data) + elif hasattr(data, '__reduce_ex__'): + reduce = data.__reduce_ex__(2) + elif hasattr(data, '__reduce__'): + reduce = data.__reduce__() + else: + raise RepresenterError("cannot represent an object", data) + reduce = (list(reduce)+[None]*5)[:5] + function, args, state, listitems, dictitems = reduce + args = list(args) + if state is None: + state = {} + if listitems is not None: + listitems = list(listitems) + if dictitems is not None: + dictitems = dict(dictitems) + if function.__name__ == '__newobj__': + function = args[0] + args = args[1:] + tag = 'tag:yaml.org,2002:python/object/new:' + newobj = True + else: + tag = 'tag:yaml.org,2002:python/object/apply:' + newobj = False + function_name = '%s.%s' % (function.__module__, function.__name__) + if not args and not listitems and not dictitems \ + and isinstance(state, dict) and newobj: + return self.represent_mapping( + 'tag:yaml.org,2002:python/object:'+function_name, state) + if not listitems and not dictitems \ + and isinstance(state, dict) and not state: + return self.represent_sequence(tag+function_name, args) + value = {} + if args: + value['args'] = args + if state or not isinstance(state, dict): + value['state'] = state + if listitems: + value['listitems'] = listitems + if dictitems: + value['dictitems'] = dictitems + return self.represent_mapping(tag+function_name, value) + + def represent_ordered_dict(self, data): + # Provide uniform representation across different Python versions. + data_type = type(data) + tag = 'tag:yaml.org,2002:python/object/apply:%s.%s' \ + % (data_type.__module__, data_type.__name__) + items = [[key, value] for key, value in data.items()] + return self.represent_sequence(tag, [items]) + +Representer.add_representer(complex, + Representer.represent_complex) + +Representer.add_representer(tuple, + Representer.represent_tuple) + +Representer.add_representer(type, + Representer.represent_name) + +Representer.add_representer(collections.OrderedDict, + Representer.represent_ordered_dict) + +Representer.add_representer(types.FunctionType, + Representer.represent_name) + +Representer.add_representer(types.BuiltinFunctionType, + Representer.represent_name) + +Representer.add_representer(types.ModuleType, + Representer.represent_module) + +Representer.add_multi_representer(object, + Representer.represent_object) + diff --git a/yaml/resolver.py b/yaml/resolver.py new file mode 100644 index 0000000..02b82e7 --- /dev/null +++ b/yaml/resolver.py @@ -0,0 +1,227 @@ + +__all__ = ['BaseResolver', 'Resolver'] + +from .error import * +from .nodes import * + +import re + +class ResolverError(YAMLError): + pass + +class BaseResolver: + + DEFAULT_SCALAR_TAG = 'tag:yaml.org,2002:str' + DEFAULT_SEQUENCE_TAG = 'tag:yaml.org,2002:seq' + DEFAULT_MAPPING_TAG = 'tag:yaml.org,2002:map' + + yaml_implicit_resolvers = {} + yaml_path_resolvers = {} + + def __init__(self): + self.resolver_exact_paths = [] + self.resolver_prefix_paths = [] + + @classmethod + def add_implicit_resolver(cls, tag, regexp, first): + if not 'yaml_implicit_resolvers' in cls.__dict__: + implicit_resolvers = {} + for key in cls.yaml_implicit_resolvers: + implicit_resolvers[key] = cls.yaml_implicit_resolvers[key][:] + cls.yaml_implicit_resolvers = implicit_resolvers + if first is None: + first = [None] + for ch in first: + cls.yaml_implicit_resolvers.setdefault(ch, []).append((tag, regexp)) + + @classmethod + def add_path_resolver(cls, tag, path, kind=None): + # Note: `add_path_resolver` is experimental. The API could be changed. + # `new_path` is a pattern that is matched against the path from the + # root to the node that is being considered. `node_path` elements are + # tuples `(node_check, index_check)`. `node_check` is a node class: + # `ScalarNode`, `SequenceNode`, `MappingNode` or `None`. `None` + # matches any kind of a node. `index_check` could be `None`, a boolean + # value, a string value, or a number. `None` and `False` match against + # any _value_ of sequence and mapping nodes. `True` matches against + # any _key_ of a mapping node. A string `index_check` matches against + # a mapping value that corresponds to a scalar key which content is + # equal to the `index_check` value. An integer `index_check` matches + # against a sequence value with the index equal to `index_check`. + if not 'yaml_path_resolvers' in cls.__dict__: + cls.yaml_path_resolvers = cls.yaml_path_resolvers.copy() + new_path = [] + for element in path: + if isinstance(element, (list, tuple)): + if len(element) == 2: + node_check, index_check = element + elif len(element) == 1: + node_check = element[0] + index_check = True + else: + raise ResolverError("Invalid path element: %s" % element) + else: + node_check = None + index_check = element + if node_check is str: + node_check = ScalarNode + elif node_check is list: + node_check = SequenceNode + elif node_check is dict: + node_check = MappingNode + elif node_check not in [ScalarNode, SequenceNode, MappingNode] \ + and not isinstance(node_check, str) \ + and node_check is not None: + raise ResolverError("Invalid node checker: %s" % node_check) + if not isinstance(index_check, (str, int)) \ + and index_check is not None: + raise ResolverError("Invalid index checker: %s" % index_check) + new_path.append((node_check, index_check)) + if kind is str: + kind = ScalarNode + elif kind is list: + kind = SequenceNode + elif kind is dict: + kind = MappingNode + elif kind not in [ScalarNode, SequenceNode, MappingNode] \ + and kind is not None: + raise ResolverError("Invalid node kind: %s" % kind) + cls.yaml_path_resolvers[tuple(new_path), kind] = tag + + def descend_resolver(self, current_node, current_index): + if not self.yaml_path_resolvers: + return + exact_paths = {} + prefix_paths = [] + if current_node: + depth = len(self.resolver_prefix_paths) + for path, kind in self.resolver_prefix_paths[-1]: + if self.check_resolver_prefix(depth, path, kind, + current_node, current_index): + if len(path) > depth: + prefix_paths.append((path, kind)) + else: + exact_paths[kind] = self.yaml_path_resolvers[path, kind] + else: + for path, kind in self.yaml_path_resolvers: + if not path: + exact_paths[kind] = self.yaml_path_resolvers[path, kind] + else: + prefix_paths.append((path, kind)) + self.resolver_exact_paths.append(exact_paths) + self.resolver_prefix_paths.append(prefix_paths) + + def ascend_resolver(self): + if not self.yaml_path_resolvers: + return + self.resolver_exact_paths.pop() + self.resolver_prefix_paths.pop() + + def check_resolver_prefix(self, depth, path, kind, + current_node, current_index): + node_check, index_check = path[depth-1] + if isinstance(node_check, str): + if current_node.tag != node_check: + return + elif node_check is not None: + if not isinstance(current_node, node_check): + return + if index_check is True and current_index is not None: + return + if (index_check is False or index_check is None) \ + and current_index is None: + return + if isinstance(index_check, str): + if not (isinstance(current_index, ScalarNode) + and index_check == current_index.value): + return + elif isinstance(index_check, int) and not isinstance(index_check, bool): + if index_check != current_index: + return + return True + + def resolve(self, kind, value, implicit): + if kind is ScalarNode and implicit[0]: + if value == '': + resolvers = self.yaml_implicit_resolvers.get('', []) + else: + resolvers = self.yaml_implicit_resolvers.get(value[0], []) + resolvers += self.yaml_implicit_resolvers.get(None, []) + for tag, regexp in resolvers: + if regexp.match(value): + return tag + implicit = implicit[1] + if self.yaml_path_resolvers: + exact_paths = self.resolver_exact_paths[-1] + if kind in exact_paths: + return exact_paths[kind] + if None in exact_paths: + return exact_paths[None] + if kind is ScalarNode: + return self.DEFAULT_SCALAR_TAG + elif kind is SequenceNode: + return self.DEFAULT_SEQUENCE_TAG + elif kind is MappingNode: + return self.DEFAULT_MAPPING_TAG + +class Resolver(BaseResolver): + pass + +Resolver.add_implicit_resolver( + 'tag:yaml.org,2002:bool', + re.compile(r'''^(?:yes|Yes|YES|no|No|NO + |true|True|TRUE|false|False|FALSE + |on|On|ON|off|Off|OFF)$''', re.X), + list('yYnNtTfFoO')) + +Resolver.add_implicit_resolver( + 'tag:yaml.org,2002:float', + re.compile(r'''^(?:[-+]?(?:[0-9][0-9_]*)\.[0-9_]*(?:[eE][-+][0-9]+)? + |\.[0-9_]+(?:[eE][-+][0-9]+)? + |[-+]?[0-9][0-9_]*(?::[0-5]?[0-9])+\.[0-9_]* + |[-+]?\.(?:inf|Inf|INF) + |\.(?:nan|NaN|NAN))$''', re.X), + list('-+0123456789.')) + +Resolver.add_implicit_resolver( + 'tag:yaml.org,2002:int', + re.compile(r'''^(?:[-+]?0b[0-1_]+ + |[-+]?0[0-7_]+ + |[-+]?(?:0|[1-9][0-9_]*) + |[-+]?0x[0-9a-fA-F_]+ + |[-+]?[1-9][0-9_]*(?::[0-5]?[0-9])+)$''', re.X), + list('-+0123456789')) + +Resolver.add_implicit_resolver( + 'tag:yaml.org,2002:merge', + re.compile(r'^(?:<<)$'), + ['<']) + +Resolver.add_implicit_resolver( + 'tag:yaml.org,2002:null', + re.compile(r'''^(?: ~ + |null|Null|NULL + | )$''', re.X), + ['~', 'n', 'N', '']) + +Resolver.add_implicit_resolver( + 'tag:yaml.org,2002:timestamp', + re.compile(r'''^(?:[0-9][0-9][0-9][0-9]-[0-9][0-9]-[0-9][0-9] + |[0-9][0-9][0-9][0-9] -[0-9][0-9]? -[0-9][0-9]? + (?:[Tt]|[ \t]+)[0-9][0-9]? + :[0-9][0-9] :[0-9][0-9] (?:\.[0-9]*)? + (?:[ \t]*(?:Z|[-+][0-9][0-9]?(?::[0-9][0-9])?))?)$''', re.X), + list('0123456789')) + +Resolver.add_implicit_resolver( + 'tag:yaml.org,2002:value', + re.compile(r'^(?:=)$'), + ['=']) + +# The following resolver is only for documentation purposes. It cannot work +# because plain scalars cannot start with '!', '&', or '*'. +Resolver.add_implicit_resolver( + 'tag:yaml.org,2002:yaml', + re.compile(r'^(?:!|&|\*)$'), + list('!&*')) + diff --git a/yaml/scanner.py b/yaml/scanner.py new file mode 100644 index 0000000..7437ede --- /dev/null +++ b/yaml/scanner.py @@ -0,0 +1,1435 @@ + +# Scanner produces tokens of the following types: +# STREAM-START +# STREAM-END +# DIRECTIVE(name, value) +# DOCUMENT-START +# DOCUMENT-END +# BLOCK-SEQUENCE-START +# BLOCK-MAPPING-START +# BLOCK-END +# FLOW-SEQUENCE-START +# FLOW-MAPPING-START +# FLOW-SEQUENCE-END +# FLOW-MAPPING-END +# BLOCK-ENTRY +# FLOW-ENTRY +# KEY +# VALUE +# ALIAS(value) +# ANCHOR(value) +# TAG(value) +# SCALAR(value, plain, style) +# +# Read comments in the Scanner code for more details. +# + +__all__ = ['Scanner', 'ScannerError'] + +from .error import MarkedYAMLError +from .tokens import * + +class ScannerError(MarkedYAMLError): + pass + +class SimpleKey: + # See below simple keys treatment. + + def __init__(self, token_number, required, index, line, column, mark): + self.token_number = token_number + self.required = required + self.index = index + self.line = line + self.column = column + self.mark = mark + +class Scanner: + + def __init__(self): + """Initialize the scanner.""" + # It is assumed that Scanner and Reader will have a common descendant. + # Reader do the dirty work of checking for BOM and converting the + # input data to Unicode. It also adds NUL to the end. + # + # Reader supports the following methods + # self.peek(i=0) # peek the next i-th character + # self.prefix(l=1) # peek the next l characters + # self.forward(l=1) # read the next l characters and move the pointer. + + # Had we reached the end of the stream? + self.done = False + + # The number of unclosed '{' and '['. `flow_level == 0` means block + # context. + self.flow_level = 0 + + # List of processed tokens that are not yet emitted. + self.tokens = [] + + # Add the STREAM-START token. + self.fetch_stream_start() + + # Number of tokens that were emitted through the `get_token` method. + self.tokens_taken = 0 + + # The current indentation level. + self.indent = -1 + + # Past indentation levels. + self.indents = [] + + # Variables related to simple keys treatment. + + # A simple key is a key that is not denoted by the '?' indicator. + # Example of simple keys: + # --- + # block simple key: value + # ? not a simple key: + # : { flow simple key: value } + # We emit the KEY token before all keys, so when we find a potential + # simple key, we try to locate the corresponding ':' indicator. + # Simple keys should be limited to a single line and 1024 characters. + + # Can a simple key start at the current position? A simple key may + # start: + # - at the beginning of the line, not counting indentation spaces + # (in block context), + # - after '{', '[', ',' (in the flow context), + # - after '?', ':', '-' (in the block context). + # In the block context, this flag also signifies if a block collection + # may start at the current position. + self.allow_simple_key = True + + # Keep track of possible simple keys. This is a dictionary. The key + # is `flow_level`; there can be no more that one possible simple key + # for each level. The value is a SimpleKey record: + # (token_number, required, index, line, column, mark) + # A simple key may start with ALIAS, ANCHOR, TAG, SCALAR(flow), + # '[', or '{' tokens. + self.possible_simple_keys = {} + + # Public methods. + + def check_token(self, *choices): + # Check if the next token is one of the given types. + while self.need_more_tokens(): + self.fetch_more_tokens() + if self.tokens: + if not choices: + return True + for choice in choices: + if isinstance(self.tokens[0], choice): + return True + return False + + def peek_token(self): + # Return the next token, but do not delete if from the queue. + # Return None if no more tokens. + while self.need_more_tokens(): + self.fetch_more_tokens() + if self.tokens: + return self.tokens[0] + else: + return None + + def get_token(self): + # Return the next token. + while self.need_more_tokens(): + self.fetch_more_tokens() + if self.tokens: + self.tokens_taken += 1 + return self.tokens.pop(0) + + # Private methods. + + def need_more_tokens(self): + if self.done: + return False + if not self.tokens: + return True + # The current token may be a potential simple key, so we + # need to look further. + self.stale_possible_simple_keys() + if self.next_possible_simple_key() == self.tokens_taken: + return True + + def fetch_more_tokens(self): + + # Eat whitespaces and comments until we reach the next token. + self.scan_to_next_token() + + # Remove obsolete possible simple keys. + self.stale_possible_simple_keys() + + # Compare the current indentation and column. It may add some tokens + # and decrease the current indentation level. + self.unwind_indent(self.column) + + # Peek the next character. + ch = self.peek() + + # Is it the end of stream? + if ch == '\0': + return self.fetch_stream_end() + + # Is it a directive? + if ch == '%' and self.check_directive(): + return self.fetch_directive() + + # Is it the document start? + if ch == '-' and self.check_document_start(): + return self.fetch_document_start() + + # Is it the document end? + if ch == '.' and self.check_document_end(): + return self.fetch_document_end() + + # TODO: support for BOM within a stream. + #if ch == '\uFEFF': + # return self.fetch_bom() <-- issue BOMToken + + # Note: the order of the following checks is NOT significant. + + # Is it the flow sequence start indicator? + if ch == '[': + return self.fetch_flow_sequence_start() + + # Is it the flow mapping start indicator? + if ch == '{': + return self.fetch_flow_mapping_start() + + # Is it the flow sequence end indicator? + if ch == ']': + return self.fetch_flow_sequence_end() + + # Is it the flow mapping end indicator? + if ch == '}': + return self.fetch_flow_mapping_end() + + # Is it the flow entry indicator? + if ch == ',': + return self.fetch_flow_entry() + + # Is it the block entry indicator? + if ch == '-' and self.check_block_entry(): + return self.fetch_block_entry() + + # Is it the key indicator? + if ch == '?' and self.check_key(): + return self.fetch_key() + + # Is it the value indicator? + if ch == ':' and self.check_value(): + return self.fetch_value() + + # Is it an alias? + if ch == '*': + return self.fetch_alias() + + # Is it an anchor? + if ch == '&': + return self.fetch_anchor() + + # Is it a tag? + if ch == '!': + return self.fetch_tag() + + # Is it a literal scalar? + if ch == '|' and not self.flow_level: + return self.fetch_literal() + + # Is it a folded scalar? + if ch == '>' and not self.flow_level: + return self.fetch_folded() + + # Is it a single quoted scalar? + if ch == '\'': + return self.fetch_single() + + # Is it a double quoted scalar? + if ch == '\"': + return self.fetch_double() + + # It must be a plain scalar then. + if self.check_plain(): + return self.fetch_plain() + + # No? It's an error. Let's produce a nice error message. + raise ScannerError("while scanning for the next token", None, + "found character %r that cannot start any token" % ch, + self.get_mark()) + + # Simple keys treatment. + + def next_possible_simple_key(self): + # Return the number of the nearest possible simple key. Actually we + # don't need to loop through the whole dictionary. We may replace it + # with the following code: + # if not self.possible_simple_keys: + # return None + # return self.possible_simple_keys[ + # min(self.possible_simple_keys.keys())].token_number + min_token_number = None + for level in self.possible_simple_keys: + key = self.possible_simple_keys[level] + if min_token_number is None or key.token_number < min_token_number: + min_token_number = key.token_number + return min_token_number + + def stale_possible_simple_keys(self): + # Remove entries that are no longer possible simple keys. According to + # the YAML specification, simple keys + # - should be limited to a single line, + # - should be no longer than 1024 characters. + # Disabling this procedure will allow simple keys of any length and + # height (may cause problems if indentation is broken though). + for level in list(self.possible_simple_keys): + key = self.possible_simple_keys[level] + if key.line != self.line \ + or self.index-key.index > 1024: + if key.required: + raise ScannerError("while scanning a simple key", key.mark, + "could not find expected ':'", self.get_mark()) + del self.possible_simple_keys[level] + + def save_possible_simple_key(self): + # The next token may start a simple key. We check if it's possible + # and save its position. This function is called for + # ALIAS, ANCHOR, TAG, SCALAR(flow), '[', and '{'. + + # Check if a simple key is required at the current position. + required = not self.flow_level and self.indent == self.column + + # The next token might be a simple key. Let's save it's number and + # position. + if self.allow_simple_key: + self.remove_possible_simple_key() + token_number = self.tokens_taken+len(self.tokens) + key = SimpleKey(token_number, required, + self.index, self.line, self.column, self.get_mark()) + self.possible_simple_keys[self.flow_level] = key + + def remove_possible_simple_key(self): + # Remove the saved possible key position at the current flow level. + if self.flow_level in self.possible_simple_keys: + key = self.possible_simple_keys[self.flow_level] + + if key.required: + raise ScannerError("while scanning a simple key", key.mark, + "could not find expected ':'", self.get_mark()) + + del self.possible_simple_keys[self.flow_level] + + # Indentation functions. + + def unwind_indent(self, column): + + ## In flow context, tokens should respect indentation. + ## Actually the condition should be `self.indent >= column` according to + ## the spec. But this condition will prohibit intuitively correct + ## constructions such as + ## key : { + ## } + #if self.flow_level and self.indent > column: + # raise ScannerError(None, None, + # "invalid indentation or unclosed '[' or '{'", + # self.get_mark()) + + # In the flow context, indentation is ignored. We make the scanner less + # restrictive then specification requires. + if self.flow_level: + return + + # In block context, we may need to issue the BLOCK-END tokens. + while self.indent > column: + mark = self.get_mark() + self.indent = self.indents.pop() + self.tokens.append(BlockEndToken(mark, mark)) + + def add_indent(self, column): + # Check if we need to increase indentation. + if self.indent < column: + self.indents.append(self.indent) + self.indent = column + return True + return False + + # Fetchers. + + def fetch_stream_start(self): + # We always add STREAM-START as the first token and STREAM-END as the + # last token. + + # Read the token. + mark = self.get_mark() + + # Add STREAM-START. + self.tokens.append(StreamStartToken(mark, mark, + encoding=self.encoding)) + + + def fetch_stream_end(self): + + # Set the current indentation to -1. + self.unwind_indent(-1) + + # Reset simple keys. + self.remove_possible_simple_key() + self.allow_simple_key = False + self.possible_simple_keys = {} + + # Read the token. + mark = self.get_mark() + + # Add STREAM-END. + self.tokens.append(StreamEndToken(mark, mark)) + + # The steam is finished. + self.done = True + + def fetch_directive(self): + + # Set the current indentation to -1. + self.unwind_indent(-1) + + # Reset simple keys. + self.remove_possible_simple_key() + self.allow_simple_key = False + + # Scan and add DIRECTIVE. + self.tokens.append(self.scan_directive()) + + def fetch_document_start(self): + self.fetch_document_indicator(DocumentStartToken) + + def fetch_document_end(self): + self.fetch_document_indicator(DocumentEndToken) + + def fetch_document_indicator(self, TokenClass): + + # Set the current indentation to -1. + self.unwind_indent(-1) + + # Reset simple keys. Note that there could not be a block collection + # after '---'. + self.remove_possible_simple_key() + self.allow_simple_key = False + + # Add DOCUMENT-START or DOCUMENT-END. + start_mark = self.get_mark() + self.forward(3) + end_mark = self.get_mark() + self.tokens.append(TokenClass(start_mark, end_mark)) + + def fetch_flow_sequence_start(self): + self.fetch_flow_collection_start(FlowSequenceStartToken) + + def fetch_flow_mapping_start(self): + self.fetch_flow_collection_start(FlowMappingStartToken) + + def fetch_flow_collection_start(self, TokenClass): + + # '[' and '{' may start a simple key. + self.save_possible_simple_key() + + # Increase the flow level. + self.flow_level += 1 + + # Simple keys are allowed after '[' and '{'. + self.allow_simple_key = True + + # Add FLOW-SEQUENCE-START or FLOW-MAPPING-START. + start_mark = self.get_mark() + self.forward() + end_mark = self.get_mark() + self.tokens.append(TokenClass(start_mark, end_mark)) + + def fetch_flow_sequence_end(self): + self.fetch_flow_collection_end(FlowSequenceEndToken) + + def fetch_flow_mapping_end(self): + self.fetch_flow_collection_end(FlowMappingEndToken) + + def fetch_flow_collection_end(self, TokenClass): + + # Reset possible simple key on the current level. + self.remove_possible_simple_key() + + # Decrease the flow level. + self.flow_level -= 1 + + # No simple keys after ']' or '}'. + self.allow_simple_key = False + + # Add FLOW-SEQUENCE-END or FLOW-MAPPING-END. + start_mark = self.get_mark() + self.forward() + end_mark = self.get_mark() + self.tokens.append(TokenClass(start_mark, end_mark)) + + def fetch_flow_entry(self): + + # Simple keys are allowed after ','. + self.allow_simple_key = True + + # Reset possible simple key on the current level. + self.remove_possible_simple_key() + + # Add FLOW-ENTRY. + start_mark = self.get_mark() + self.forward() + end_mark = self.get_mark() + self.tokens.append(FlowEntryToken(start_mark, end_mark)) + + def fetch_block_entry(self): + + # Block context needs additional checks. + if not self.flow_level: + + # Are we allowed to start a new entry? + if not self.allow_simple_key: + raise ScannerError(None, None, + "sequence entries are not allowed here", + self.get_mark()) + + # We may need to add BLOCK-SEQUENCE-START. + if self.add_indent(self.column): + mark = self.get_mark() + self.tokens.append(BlockSequenceStartToken(mark, mark)) + + # It's an error for the block entry to occur in the flow context, + # but we let the parser detect this. + else: + pass + + # Simple keys are allowed after '-'. + self.allow_simple_key = True + + # Reset possible simple key on the current level. + self.remove_possible_simple_key() + + # Add BLOCK-ENTRY. + start_mark = self.get_mark() + self.forward() + end_mark = self.get_mark() + self.tokens.append(BlockEntryToken(start_mark, end_mark)) + + def fetch_key(self): + + # Block context needs additional checks. + if not self.flow_level: + + # Are we allowed to start a key (not necessary a simple)? + if not self.allow_simple_key: + raise ScannerError(None, None, + "mapping keys are not allowed here", + self.get_mark()) + + # We may need to add BLOCK-MAPPING-START. + if self.add_indent(self.column): + mark = self.get_mark() + self.tokens.append(BlockMappingStartToken(mark, mark)) + + # Simple keys are allowed after '?' in the block context. + self.allow_simple_key = not self.flow_level + + # Reset possible simple key on the current level. + self.remove_possible_simple_key() + + # Add KEY. + start_mark = self.get_mark() + self.forward() + end_mark = self.get_mark() + self.tokens.append(KeyToken(start_mark, end_mark)) + + def fetch_value(self): + + # Do we determine a simple key? + if self.flow_level in self.possible_simple_keys: + + # Add KEY. + key = self.possible_simple_keys[self.flow_level] + del self.possible_simple_keys[self.flow_level] + self.tokens.insert(key.token_number-self.tokens_taken, + KeyToken(key.mark, key.mark)) + + # If this key starts a new block mapping, we need to add + # BLOCK-MAPPING-START. + if not self.flow_level: + if self.add_indent(key.column): + self.tokens.insert(key.token_number-self.tokens_taken, + BlockMappingStartToken(key.mark, key.mark)) + + # There cannot be two simple keys one after another. + self.allow_simple_key = False + + # It must be a part of a complex key. + else: + + # Block context needs additional checks. + # (Do we really need them? They will be caught by the parser + # anyway.) + if not self.flow_level: + + # We are allowed to start a complex value if and only if + # we can start a simple key. + if not self.allow_simple_key: + raise ScannerError(None, None, + "mapping values are not allowed here", + self.get_mark()) + + # If this value starts a new block mapping, we need to add + # BLOCK-MAPPING-START. It will be detected as an error later by + # the parser. + if not self.flow_level: + if self.add_indent(self.column): + mark = self.get_mark() + self.tokens.append(BlockMappingStartToken(mark, mark)) + + # Simple keys are allowed after ':' in the block context. + self.allow_simple_key = not self.flow_level + + # Reset possible simple key on the current level. + self.remove_possible_simple_key() + + # Add VALUE. + start_mark = self.get_mark() + self.forward() + end_mark = self.get_mark() + self.tokens.append(ValueToken(start_mark, end_mark)) + + def fetch_alias(self): + + # ALIAS could be a simple key. + self.save_possible_simple_key() + + # No simple keys after ALIAS. + self.allow_simple_key = False + + # Scan and add ALIAS. + self.tokens.append(self.scan_anchor(AliasToken)) + + def fetch_anchor(self): + + # ANCHOR could start a simple key. + self.save_possible_simple_key() + + # No simple keys after ANCHOR. + self.allow_simple_key = False + + # Scan and add ANCHOR. + self.tokens.append(self.scan_anchor(AnchorToken)) + + def fetch_tag(self): + + # TAG could start a simple key. + self.save_possible_simple_key() + + # No simple keys after TAG. + self.allow_simple_key = False + + # Scan and add TAG. + self.tokens.append(self.scan_tag()) + + def fetch_literal(self): + self.fetch_block_scalar(style='|') + + def fetch_folded(self): + self.fetch_block_scalar(style='>') + + def fetch_block_scalar(self, style): + + # A simple key may follow a block scalar. + self.allow_simple_key = True + + # Reset possible simple key on the current level. + self.remove_possible_simple_key() + + # Scan and add SCALAR. + self.tokens.append(self.scan_block_scalar(style)) + + def fetch_single(self): + self.fetch_flow_scalar(style='\'') + + def fetch_double(self): + self.fetch_flow_scalar(style='"') + + def fetch_flow_scalar(self, style): + + # A flow scalar could be a simple key. + self.save_possible_simple_key() + + # No simple keys after flow scalars. + self.allow_simple_key = False + + # Scan and add SCALAR. + self.tokens.append(self.scan_flow_scalar(style)) + + def fetch_plain(self): + + # A plain scalar could be a simple key. + self.save_possible_simple_key() + + # No simple keys after plain scalars. But note that `scan_plain` will + # change this flag if the scan is finished at the beginning of the + # line. + self.allow_simple_key = False + + # Scan and add SCALAR. May change `allow_simple_key`. + self.tokens.append(self.scan_plain()) + + # Checkers. + + def check_directive(self): + + # DIRECTIVE: ^ '%' ... + # The '%' indicator is already checked. + if self.column == 0: + return True + + def check_document_start(self): + + # DOCUMENT-START: ^ '---' (' '|'\n') + if self.column == 0: + if self.prefix(3) == '---' \ + and self.peek(3) in '\0 \t\r\n\x85\u2028\u2029': + return True + + def check_document_end(self): + + # DOCUMENT-END: ^ '...' (' '|'\n') + if self.column == 0: + if self.prefix(3) == '...' \ + and self.peek(3) in '\0 \t\r\n\x85\u2028\u2029': + return True + + def check_block_entry(self): + + # BLOCK-ENTRY: '-' (' '|'\n') + return self.peek(1) in '\0 \t\r\n\x85\u2028\u2029' + + def check_key(self): + + # KEY(flow context): '?' + if self.flow_level: + return True + + # KEY(block context): '?' (' '|'\n') + else: + return self.peek(1) in '\0 \t\r\n\x85\u2028\u2029' + + def check_value(self): + + # VALUE(flow context): ':' + if self.flow_level: + return True + + # VALUE(block context): ':' (' '|'\n') + else: + return self.peek(1) in '\0 \t\r\n\x85\u2028\u2029' + + def check_plain(self): + + # A plain scalar may start with any non-space character except: + # '-', '?', ':', ',', '[', ']', '{', '}', + # '#', '&', '*', '!', '|', '>', '\'', '\"', + # '%', '@', '`'. + # + # It may also start with + # '-', '?', ':' + # if it is followed by a non-space character. + # + # Note that we limit the last rule to the block context (except the + # '-' character) because we want the flow context to be space + # independent. + ch = self.peek() + return ch not in '\0 \t\r\n\x85\u2028\u2029-?:,[]{}#&*!|>\'\"%@`' \ + or (self.peek(1) not in '\0 \t\r\n\x85\u2028\u2029' + and (ch == '-' or (not self.flow_level and ch in '?:'))) + + # Scanners. + + def scan_to_next_token(self): + # We ignore spaces, line breaks and comments. + # If we find a line break in the block context, we set the flag + # `allow_simple_key` on. + # The byte order mark is stripped if it's the first character in the + # stream. We do not yet support BOM inside the stream as the + # specification requires. Any such mark will be considered as a part + # of the document. + # + # TODO: We need to make tab handling rules more sane. A good rule is + # Tabs cannot precede tokens + # BLOCK-SEQUENCE-START, BLOCK-MAPPING-START, BLOCK-END, + # KEY(block), VALUE(block), BLOCK-ENTRY + # So the checking code is + # if <TAB>: + # self.allow_simple_keys = False + # We also need to add the check for `allow_simple_keys == True` to + # `unwind_indent` before issuing BLOCK-END. + # Scanners for block, flow, and plain scalars need to be modified. + + if self.index == 0 and self.peek() == '\uFEFF': + self.forward() + found = False + while not found: + while self.peek() == ' ': + self.forward() + if self.peek() == '#': + while self.peek() not in '\0\r\n\x85\u2028\u2029': + self.forward() + if self.scan_line_break(): + if not self.flow_level: + self.allow_simple_key = True + else: + found = True + + def scan_directive(self): + # See the specification for details. + start_mark = self.get_mark() + self.forward() + name = self.scan_directive_name(start_mark) + value = None + if name == 'YAML': + value = self.scan_yaml_directive_value(start_mark) + end_mark = self.get_mark() + elif name == 'TAG': + value = self.scan_tag_directive_value(start_mark) + end_mark = self.get_mark() + else: + end_mark = self.get_mark() + while self.peek() not in '\0\r\n\x85\u2028\u2029': + self.forward() + self.scan_directive_ignored_line(start_mark) + return DirectiveToken(name, value, start_mark, end_mark) + + def scan_directive_name(self, start_mark): + # See the specification for details. + length = 0 + ch = self.peek(length) + while '0' <= ch <= '9' or 'A' <= ch <= 'Z' or 'a' <= ch <= 'z' \ + or ch in '-_': + length += 1 + ch = self.peek(length) + if not length: + raise ScannerError("while scanning a directive", start_mark, + "expected alphabetic or numeric character, but found %r" + % ch, self.get_mark()) + value = self.prefix(length) + self.forward(length) + ch = self.peek() + if ch not in '\0 \r\n\x85\u2028\u2029': + raise ScannerError("while scanning a directive", start_mark, + "expected alphabetic or numeric character, but found %r" + % ch, self.get_mark()) + return value + + def scan_yaml_directive_value(self, start_mark): + # See the specification for details. + while self.peek() == ' ': + self.forward() + major = self.scan_yaml_directive_number(start_mark) + if self.peek() != '.': + raise ScannerError("while scanning a directive", start_mark, + "expected a digit or '.', but found %r" % self.peek(), + self.get_mark()) + self.forward() + minor = self.scan_yaml_directive_number(start_mark) + if self.peek() not in '\0 \r\n\x85\u2028\u2029': + raise ScannerError("while scanning a directive", start_mark, + "expected a digit or ' ', but found %r" % self.peek(), + self.get_mark()) + return (major, minor) + + def scan_yaml_directive_number(self, start_mark): + # See the specification for details. + ch = self.peek() + if not ('0' <= ch <= '9'): + raise ScannerError("while scanning a directive", start_mark, + "expected a digit, but found %r" % ch, self.get_mark()) + length = 0 + while '0' <= self.peek(length) <= '9': + length += 1 + value = int(self.prefix(length)) + self.forward(length) + return value + + def scan_tag_directive_value(self, start_mark): + # See the specification for details. + while self.peek() == ' ': + self.forward() + handle = self.scan_tag_directive_handle(start_mark) + while self.peek() == ' ': + self.forward() + prefix = self.scan_tag_directive_prefix(start_mark) + return (handle, prefix) + + def scan_tag_directive_handle(self, start_mark): + # See the specification for details. + value = self.scan_tag_handle('directive', start_mark) + ch = self.peek() + if ch != ' ': + raise ScannerError("while scanning a directive", start_mark, + "expected ' ', but found %r" % ch, self.get_mark()) + return value + + def scan_tag_directive_prefix(self, start_mark): + # See the specification for details. + value = self.scan_tag_uri('directive', start_mark) + ch = self.peek() + if ch not in '\0 \r\n\x85\u2028\u2029': + raise ScannerError("while scanning a directive", start_mark, + "expected ' ', but found %r" % ch, self.get_mark()) + return value + + def scan_directive_ignored_line(self, start_mark): + # See the specification for details. + while self.peek() == ' ': + self.forward() + if self.peek() == '#': + while self.peek() not in '\0\r\n\x85\u2028\u2029': + self.forward() + ch = self.peek() + if ch not in '\0\r\n\x85\u2028\u2029': + raise ScannerError("while scanning a directive", start_mark, + "expected a comment or a line break, but found %r" + % ch, self.get_mark()) + self.scan_line_break() + + def scan_anchor(self, TokenClass): + # The specification does not restrict characters for anchors and + # aliases. This may lead to problems, for instance, the document: + # [ *alias, value ] + # can be interpreted in two ways, as + # [ "value" ] + # and + # [ *alias , "value" ] + # Therefore we restrict aliases to numbers and ASCII letters. + start_mark = self.get_mark() + indicator = self.peek() + if indicator == '*': + name = 'alias' + else: + name = 'anchor' + self.forward() + length = 0 + ch = self.peek(length) + while '0' <= ch <= '9' or 'A' <= ch <= 'Z' or 'a' <= ch <= 'z' \ + or ch in '-_': + length += 1 + ch = self.peek(length) + if not length: + raise ScannerError("while scanning an %s" % name, start_mark, + "expected alphabetic or numeric character, but found %r" + % ch, self.get_mark()) + value = self.prefix(length) + self.forward(length) + ch = self.peek() + if ch not in '\0 \t\r\n\x85\u2028\u2029?:,]}%@`': + raise ScannerError("while scanning an %s" % name, start_mark, + "expected alphabetic or numeric character, but found %r" + % ch, self.get_mark()) + end_mark = self.get_mark() + return TokenClass(value, start_mark, end_mark) + + def scan_tag(self): + # See the specification for details. + start_mark = self.get_mark() + ch = self.peek(1) + if ch == '<': + handle = None + self.forward(2) + suffix = self.scan_tag_uri('tag', start_mark) + if self.peek() != '>': + raise ScannerError("while parsing a tag", start_mark, + "expected '>', but found %r" % self.peek(), + self.get_mark()) + self.forward() + elif ch in '\0 \t\r\n\x85\u2028\u2029': + handle = None + suffix = '!' + self.forward() + else: + length = 1 + use_handle = False + while ch not in '\0 \r\n\x85\u2028\u2029': + if ch == '!': + use_handle = True + break + length += 1 + ch = self.peek(length) + handle = '!' + if use_handle: + handle = self.scan_tag_handle('tag', start_mark) + else: + handle = '!' + self.forward() + suffix = self.scan_tag_uri('tag', start_mark) + ch = self.peek() + if ch not in '\0 \r\n\x85\u2028\u2029': + raise ScannerError("while scanning a tag", start_mark, + "expected ' ', but found %r" % ch, self.get_mark()) + value = (handle, suffix) + end_mark = self.get_mark() + return TagToken(value, start_mark, end_mark) + + def scan_block_scalar(self, style): + # See the specification for details. + + if style == '>': + folded = True + else: + folded = False + + chunks = [] + start_mark = self.get_mark() + + # Scan the header. + self.forward() + chomping, increment = self.scan_block_scalar_indicators(start_mark) + self.scan_block_scalar_ignored_line(start_mark) + + # Determine the indentation level and go to the first non-empty line. + min_indent = self.indent+1 + if min_indent < 1: + min_indent = 1 + if increment is None: + breaks, max_indent, end_mark = self.scan_block_scalar_indentation() + indent = max(min_indent, max_indent) + else: + indent = min_indent+increment-1 + breaks, end_mark = self.scan_block_scalar_breaks(indent) + line_break = '' + + # Scan the inner part of the block scalar. + while self.column == indent and self.peek() != '\0': + chunks.extend(breaks) + leading_non_space = self.peek() not in ' \t' + length = 0 + while self.peek(length) not in '\0\r\n\x85\u2028\u2029': + length += 1 + chunks.append(self.prefix(length)) + self.forward(length) + line_break = self.scan_line_break() + breaks, end_mark = self.scan_block_scalar_breaks(indent) + if self.column == indent and self.peek() != '\0': + + # Unfortunately, folding rules are ambiguous. + # + # This is the folding according to the specification: + + if folded and line_break == '\n' \ + and leading_non_space and self.peek() not in ' \t': + if not breaks: + chunks.append(' ') + else: + chunks.append(line_break) + + # This is Clark Evans's interpretation (also in the spec + # examples): + # + #if folded and line_break == '\n': + # if not breaks: + # if self.peek() not in ' \t': + # chunks.append(' ') + # else: + # chunks.append(line_break) + #else: + # chunks.append(line_break) + else: + break + + # Chomp the tail. + if chomping is not False: + chunks.append(line_break) + if chomping is True: + chunks.extend(breaks) + + # We are done. + return ScalarToken(''.join(chunks), False, start_mark, end_mark, + style) + + def scan_block_scalar_indicators(self, start_mark): + # See the specification for details. + chomping = None + increment = None + ch = self.peek() + if ch in '+-': + if ch == '+': + chomping = True + else: + chomping = False + self.forward() + ch = self.peek() + if ch in '0123456789': + increment = int(ch) + if increment == 0: + raise ScannerError("while scanning a block scalar", start_mark, + "expected indentation indicator in the range 1-9, but found 0", + self.get_mark()) + self.forward() + elif ch in '0123456789': + increment = int(ch) + if increment == 0: + raise ScannerError("while scanning a block scalar", start_mark, + "expected indentation indicator in the range 1-9, but found 0", + self.get_mark()) + self.forward() + ch = self.peek() + if ch in '+-': + if ch == '+': + chomping = True + else: + chomping = False + self.forward() + ch = self.peek() + if ch not in '\0 \r\n\x85\u2028\u2029': + raise ScannerError("while scanning a block scalar", start_mark, + "expected chomping or indentation indicators, but found %r" + % ch, self.get_mark()) + return chomping, increment + + def scan_block_scalar_ignored_line(self, start_mark): + # See the specification for details. + while self.peek() == ' ': + self.forward() + if self.peek() == '#': + while self.peek() not in '\0\r\n\x85\u2028\u2029': + self.forward() + ch = self.peek() + if ch not in '\0\r\n\x85\u2028\u2029': + raise ScannerError("while scanning a block scalar", start_mark, + "expected a comment or a line break, but found %r" % ch, + self.get_mark()) + self.scan_line_break() + + def scan_block_scalar_indentation(self): + # See the specification for details. + chunks = [] + max_indent = 0 + end_mark = self.get_mark() + while self.peek() in ' \r\n\x85\u2028\u2029': + if self.peek() != ' ': + chunks.append(self.scan_line_break()) + end_mark = self.get_mark() + else: + self.forward() + if self.column > max_indent: + max_indent = self.column + return chunks, max_indent, end_mark + + def scan_block_scalar_breaks(self, indent): + # See the specification for details. + chunks = [] + end_mark = self.get_mark() + while self.column < indent and self.peek() == ' ': + self.forward() + while self.peek() in '\r\n\x85\u2028\u2029': + chunks.append(self.scan_line_break()) + end_mark = self.get_mark() + while self.column < indent and self.peek() == ' ': + self.forward() + return chunks, end_mark + + def scan_flow_scalar(self, style): + # See the specification for details. + # Note that we loose indentation rules for quoted scalars. Quoted + # scalars don't need to adhere indentation because " and ' clearly + # mark the beginning and the end of them. Therefore we are less + # restrictive then the specification requires. We only need to check + # that document separators are not included in scalars. + if style == '"': + double = True + else: + double = False + chunks = [] + start_mark = self.get_mark() + quote = self.peek() + self.forward() + chunks.extend(self.scan_flow_scalar_non_spaces(double, start_mark)) + while self.peek() != quote: + chunks.extend(self.scan_flow_scalar_spaces(double, start_mark)) + chunks.extend(self.scan_flow_scalar_non_spaces(double, start_mark)) + self.forward() + end_mark = self.get_mark() + return ScalarToken(''.join(chunks), False, start_mark, end_mark, + style) + + ESCAPE_REPLACEMENTS = { + '0': '\0', + 'a': '\x07', + 'b': '\x08', + 't': '\x09', + '\t': '\x09', + 'n': '\x0A', + 'v': '\x0B', + 'f': '\x0C', + 'r': '\x0D', + 'e': '\x1B', + ' ': '\x20', + '\"': '\"', + '\\': '\\', + '/': '/', + 'N': '\x85', + '_': '\xA0', + 'L': '\u2028', + 'P': '\u2029', + } + + ESCAPE_CODES = { + 'x': 2, + 'u': 4, + 'U': 8, + } + + def scan_flow_scalar_non_spaces(self, double, start_mark): + # See the specification for details. + chunks = [] + while True: + length = 0 + while self.peek(length) not in '\'\"\\\0 \t\r\n\x85\u2028\u2029': + length += 1 + if length: + chunks.append(self.prefix(length)) + self.forward(length) + ch = self.peek() + if not double and ch == '\'' and self.peek(1) == '\'': + chunks.append('\'') + self.forward(2) + elif (double and ch == '\'') or (not double and ch in '\"\\'): + chunks.append(ch) + self.forward() + elif double and ch == '\\': + self.forward() + ch = self.peek() + if ch in self.ESCAPE_REPLACEMENTS: + chunks.append(self.ESCAPE_REPLACEMENTS[ch]) + self.forward() + elif ch in self.ESCAPE_CODES: + length = self.ESCAPE_CODES[ch] + self.forward() + for k in range(length): + if self.peek(k) not in '0123456789ABCDEFabcdef': + raise ScannerError("while scanning a double-quoted scalar", start_mark, + "expected escape sequence of %d hexdecimal numbers, but found %r" % + (length, self.peek(k)), self.get_mark()) + code = int(self.prefix(length), 16) + chunks.append(chr(code)) + self.forward(length) + elif ch in '\r\n\x85\u2028\u2029': + self.scan_line_break() + chunks.extend(self.scan_flow_scalar_breaks(double, start_mark)) + else: + raise ScannerError("while scanning a double-quoted scalar", start_mark, + "found unknown escape character %r" % ch, self.get_mark()) + else: + return chunks + + def scan_flow_scalar_spaces(self, double, start_mark): + # See the specification for details. + chunks = [] + length = 0 + while self.peek(length) in ' \t': + length += 1 + whitespaces = self.prefix(length) + self.forward(length) + ch = self.peek() + if ch == '\0': + raise ScannerError("while scanning a quoted scalar", start_mark, + "found unexpected end of stream", self.get_mark()) + elif ch in '\r\n\x85\u2028\u2029': + line_break = self.scan_line_break() + breaks = self.scan_flow_scalar_breaks(double, start_mark) + if line_break != '\n': + chunks.append(line_break) + elif not breaks: + chunks.append(' ') + chunks.extend(breaks) + else: + chunks.append(whitespaces) + return chunks + + def scan_flow_scalar_breaks(self, double, start_mark): + # See the specification for details. + chunks = [] + while True: + # Instead of checking indentation, we check for document + # separators. + prefix = self.prefix(3) + if (prefix == '---' or prefix == '...') \ + and self.peek(3) in '\0 \t\r\n\x85\u2028\u2029': + raise ScannerError("while scanning a quoted scalar", start_mark, + "found unexpected document separator", self.get_mark()) + while self.peek() in ' \t': + self.forward() + if self.peek() in '\r\n\x85\u2028\u2029': + chunks.append(self.scan_line_break()) + else: + return chunks + + def scan_plain(self): + # See the specification for details. + # We add an additional restriction for the flow context: + # plain scalars in the flow context cannot contain ',' or '?'. + # We also keep track of the `allow_simple_key` flag here. + # Indentation rules are loosed for the flow context. + chunks = [] + start_mark = self.get_mark() + end_mark = start_mark + indent = self.indent+1 + # We allow zero indentation for scalars, but then we need to check for + # document separators at the beginning of the line. + #if indent == 0: + # indent = 1 + spaces = [] + while True: + length = 0 + if self.peek() == '#': + break + while True: + ch = self.peek(length) + if ch in '\0 \t\r\n\x85\u2028\u2029' \ + or (ch == ':' and + self.peek(length+1) in '\0 \t\r\n\x85\u2028\u2029' + + (u',[]{}' if self.flow_level else u''))\ + or (self.flow_level and ch in ',?[]{}'): + break + length += 1 + if length == 0: + break + self.allow_simple_key = False + chunks.extend(spaces) + chunks.append(self.prefix(length)) + self.forward(length) + end_mark = self.get_mark() + spaces = self.scan_plain_spaces(indent, start_mark) + if not spaces or self.peek() == '#' \ + or (not self.flow_level and self.column < indent): + break + return ScalarToken(''.join(chunks), True, start_mark, end_mark) + + def scan_plain_spaces(self, indent, start_mark): + # See the specification for details. + # The specification is really confusing about tabs in plain scalars. + # We just forbid them completely. Do not use tabs in YAML! + chunks = [] + length = 0 + while self.peek(length) in ' ': + length += 1 + whitespaces = self.prefix(length) + self.forward(length) + ch = self.peek() + if ch in '\r\n\x85\u2028\u2029': + line_break = self.scan_line_break() + self.allow_simple_key = True + prefix = self.prefix(3) + if (prefix == '---' or prefix == '...') \ + and self.peek(3) in '\0 \t\r\n\x85\u2028\u2029': + return + breaks = [] + while self.peek() in ' \r\n\x85\u2028\u2029': + if self.peek() == ' ': + self.forward() + else: + breaks.append(self.scan_line_break()) + prefix = self.prefix(3) + if (prefix == '---' or prefix == '...') \ + and self.peek(3) in '\0 \t\r\n\x85\u2028\u2029': + return + if line_break != '\n': + chunks.append(line_break) + elif not breaks: + chunks.append(' ') + chunks.extend(breaks) + elif whitespaces: + chunks.append(whitespaces) + return chunks + + def scan_tag_handle(self, name, start_mark): + # See the specification for details. + # For some strange reasons, the specification does not allow '_' in + # tag handles. I have allowed it anyway. + ch = self.peek() + if ch != '!': + raise ScannerError("while scanning a %s" % name, start_mark, + "expected '!', but found %r" % ch, self.get_mark()) + length = 1 + ch = self.peek(length) + if ch != ' ': + while '0' <= ch <= '9' or 'A' <= ch <= 'Z' or 'a' <= ch <= 'z' \ + or ch in '-_': + length += 1 + ch = self.peek(length) + if ch != '!': + self.forward(length) + raise ScannerError("while scanning a %s" % name, start_mark, + "expected '!', but found %r" % ch, self.get_mark()) + length += 1 + value = self.prefix(length) + self.forward(length) + return value + + def scan_tag_uri(self, name, start_mark): + # See the specification for details. + # Note: we do not check if URI is well-formed. + chunks = [] + length = 0 + ch = self.peek(length) + while '0' <= ch <= '9' or 'A' <= ch <= 'Z' or 'a' <= ch <= 'z' \ + or ch in '-;/?:@&=+$,_.!~*\'()[]%': + if ch == '%': + chunks.append(self.prefix(length)) + self.forward(length) + length = 0 + chunks.append(self.scan_uri_escapes(name, start_mark)) + else: + length += 1 + ch = self.peek(length) + if length: + chunks.append(self.prefix(length)) + self.forward(length) + length = 0 + if not chunks: + raise ScannerError("while parsing a %s" % name, start_mark, + "expected URI, but found %r" % ch, self.get_mark()) + return ''.join(chunks) + + def scan_uri_escapes(self, name, start_mark): + # See the specification for details. + codes = [] + mark = self.get_mark() + while self.peek() == '%': + self.forward() + for k in range(2): + if self.peek(k) not in '0123456789ABCDEFabcdef': + raise ScannerError("while scanning a %s" % name, start_mark, + "expected URI escape sequence of 2 hexdecimal numbers, but found %r" + % self.peek(k), self.get_mark()) + codes.append(int(self.prefix(2), 16)) + self.forward(2) + try: + value = bytes(codes).decode('utf-8') + except UnicodeDecodeError as exc: + raise ScannerError("while scanning a %s" % name, start_mark, str(exc), mark) + return value + + def scan_line_break(self): + # Transforms: + # '\r\n' : '\n' + # '\r' : '\n' + # '\n' : '\n' + # '\x85' : '\n' + # '\u2028' : '\u2028' + # '\u2029 : '\u2029' + # default : '' + ch = self.peek() + if ch in '\r\n\x85': + if self.prefix(2) == '\r\n': + self.forward(2) + else: + self.forward() + return '\n' + elif ch in '\u2028\u2029': + self.forward() + return ch + return '' diff --git a/yaml/serializer.py b/yaml/serializer.py new file mode 100644 index 0000000..fe911e6 --- /dev/null +++ b/yaml/serializer.py @@ -0,0 +1,111 @@ + +__all__ = ['Serializer', 'SerializerError'] + +from .error import YAMLError +from .events import * +from .nodes import * + +class SerializerError(YAMLError): + pass + +class Serializer: + + ANCHOR_TEMPLATE = 'id%03d' + + def __init__(self, encoding=None, + explicit_start=None, explicit_end=None, version=None, tags=None): + self.use_encoding = encoding + self.use_explicit_start = explicit_start + self.use_explicit_end = explicit_end + self.use_version = version + self.use_tags = tags + self.serialized_nodes = {} + self.anchors = {} + self.last_anchor_id = 0 + self.closed = None + + def open(self): + if self.closed is None: + self.emit(StreamStartEvent(encoding=self.use_encoding)) + self.closed = False + elif self.closed: + raise SerializerError("serializer is closed") + else: + raise SerializerError("serializer is already opened") + + def close(self): + if self.closed is None: + raise SerializerError("serializer is not opened") + elif not self.closed: + self.emit(StreamEndEvent()) + self.closed = True + + #def __del__(self): + # self.close() + + def serialize(self, node): + if self.closed is None: + raise SerializerError("serializer is not opened") + elif self.closed: + raise SerializerError("serializer is closed") + self.emit(DocumentStartEvent(explicit=self.use_explicit_start, + version=self.use_version, tags=self.use_tags)) + self.anchor_node(node) + self.serialize_node(node, None, None) + self.emit(DocumentEndEvent(explicit=self.use_explicit_end)) + self.serialized_nodes = {} + self.anchors = {} + self.last_anchor_id = 0 + + def anchor_node(self, node): + if node in self.anchors: + if self.anchors[node] is None: + self.anchors[node] = self.generate_anchor(node) + else: + self.anchors[node] = None + if isinstance(node, SequenceNode): + for item in node.value: + self.anchor_node(item) + elif isinstance(node, MappingNode): + for key, value in node.value: + self.anchor_node(key) + self.anchor_node(value) + + def generate_anchor(self, node): + self.last_anchor_id += 1 + return self.ANCHOR_TEMPLATE % self.last_anchor_id + + def serialize_node(self, node, parent, index): + alias = self.anchors[node] + if node in self.serialized_nodes: + self.emit(AliasEvent(alias)) + else: + self.serialized_nodes[node] = True + self.descend_resolver(parent, index) + if isinstance(node, ScalarNode): + detected_tag = self.resolve(ScalarNode, node.value, (True, False)) + default_tag = self.resolve(ScalarNode, node.value, (False, True)) + implicit = (node.tag == detected_tag), (node.tag == default_tag) + self.emit(ScalarEvent(alias, node.tag, implicit, node.value, + style=node.style)) + elif isinstance(node, SequenceNode): + implicit = (node.tag + == self.resolve(SequenceNode, node.value, True)) + self.emit(SequenceStartEvent(alias, node.tag, implicit, + flow_style=node.flow_style)) + index = 0 + for item in node.value: + self.serialize_node(item, node, index) + index += 1 + self.emit(SequenceEndEvent()) + elif isinstance(node, MappingNode): + implicit = (node.tag + == self.resolve(MappingNode, node.value, True)) + self.emit(MappingStartEvent(alias, node.tag, implicit, + flow_style=node.flow_style)) + for key, value in node.value: + self.serialize_node(key, node, None) + self.serialize_node(value, node, key) + self.emit(MappingEndEvent()) + self.ascend_resolver() + diff --git a/yaml/tokens.py b/yaml/tokens.py new file mode 100644 index 0000000..4d0b48a --- /dev/null +++ b/yaml/tokens.py @@ -0,0 +1,104 @@ + +class Token(object): + def __init__(self, start_mark, end_mark): + self.start_mark = start_mark + self.end_mark = end_mark + def __repr__(self): + attributes = [key for key in self.__dict__ + if not key.endswith('_mark')] + attributes.sort() + arguments = ', '.join(['%s=%r' % (key, getattr(self, key)) + for key in attributes]) + return '%s(%s)' % (self.__class__.__name__, arguments) + +#class BOMToken(Token): +# id = '<byte order mark>' + +class DirectiveToken(Token): + id = '<directive>' + def __init__(self, name, value, start_mark, end_mark): + self.name = name + self.value = value + self.start_mark = start_mark + self.end_mark = end_mark + +class DocumentStartToken(Token): + id = '<document start>' + +class DocumentEndToken(Token): + id = '<document end>' + +class StreamStartToken(Token): + id = '<stream start>' + def __init__(self, start_mark=None, end_mark=None, + encoding=None): + self.start_mark = start_mark + self.end_mark = end_mark + self.encoding = encoding + +class StreamEndToken(Token): + id = '<stream end>' + +class BlockSequenceStartToken(Token): + id = '<block sequence start>' + +class BlockMappingStartToken(Token): + id = '<block mapping start>' + +class BlockEndToken(Token): + id = '<block end>' + +class FlowSequenceStartToken(Token): + id = '[' + +class FlowMappingStartToken(Token): + id = '{' + +class FlowSequenceEndToken(Token): + id = ']' + +class FlowMappingEndToken(Token): + id = '}' + +class KeyToken(Token): + id = '?' + +class ValueToken(Token): + id = ':' + +class BlockEntryToken(Token): + id = '-' + +class FlowEntryToken(Token): + id = ',' + +class AliasToken(Token): + id = '<alias>' + def __init__(self, value, start_mark, end_mark): + self.value = value + self.start_mark = start_mark + self.end_mark = end_mark + +class AnchorToken(Token): + id = '<anchor>' + def __init__(self, value, start_mark, end_mark): + self.value = value + self.start_mark = start_mark + self.end_mark = end_mark + +class TagToken(Token): + id = '<tag>' + def __init__(self, value, start_mark, end_mark): + self.value = value + self.start_mark = start_mark + self.end_mark = end_mark + +class ScalarToken(Token): + id = '<scalar>' + def __init__(self, value, plain, start_mark, end_mark, style=None): + self.value = value + self.plain = plain + self.start_mark = start_mark + self.end_mark = end_mark + self.style = style + |