Add default options

This feature was implemented with feedback from Aleks Kamko
<aykamko@gmail.com> and Casey Rodarmor <casey@rodarmor.com>.

8 files changed, 126 insertions, 26 deletions

diff --git a/README.md b/README.md
index 3ed74f5..1b42f75 100644
--- a/README.md
+++ b/README.md
@@ -78,6 +78,10 @@ Here's an example of a complete configuration.
 The conventional name for the configuration file is `install.conf.yaml`.
 
 ```yaml
+- defaults:
+    link:
+      relink: true
+
 - clean: ['~']
 
 - link:
@@ -98,6 +102,13 @@ The conventional name for this file is `install.conf.json`.
 ```json
 [
     {
+        "defaults": {
+            "link": {
+                "relink": true
+            }
+        }
+    },
+    {
         "clean": ["~"]
     },
     {
@@ -225,6 +236,30 @@ Clean commands are specified as an array of directories to be cleaned.
 - clean: ['~']
 ```
 
+### Defaults
+
+Default options for plugins can be specified so that options don't have to be
+repeated many times. This can be very useful to use with the link command, for
+example.
+
+Defaults apply to all commands that follow setting the defaults. Defaults can
+be set multiple times; each change replaces the defaults with a new set of
+options.
+
+#### Format
+
+Defaults are specified as a dictionary mapping action names to settings, which
+are dictionaries from option names to values.
+
+#### Example
+
+```yaml
+- defaults:
+    link:
+      create: true
+      relink: true
+```
+
 ### Plugins
 
 Dotbot also supports custom directives implemented by plugins. Plugins are
diff --git a/dotbot/context.py b/dotbot/context.py
new file mode 100644
index 0000000..b2dbd6c
--- /dev/null
+++ b/dotbot/context.py
@@ -0,0 +1,23 @@
+import copy
+
+class Context(object):
+    '''
+    Contextual data and information for plugins.
+    '''
+
+    def __init__(self, base_directory):
+        self._base_directory = base_directory
+        self._defaults = {}
+        pass
+
+    def set_base_directory(self, base_directory):
+        self._base_directory = base_directory
+
+    def base_directory(self):
+        return self._base_directory
+
+    def set_defaults(self, defaults):
+        self._defaults = defaults
+
+    def defaults(self):
+        return copy.deepcopy(self._defaults)
diff --git a/dotbot/dispatcher.py b/dotbot/dispatcher.py
index 79231a0..cc07435 100644
--- a/dotbot/dispatcher.py
+++ b/dotbot/dispatcher.py
@@ -1,26 +1,30 @@
 import os
 from .plugin import Plugin
 from .messenger import Messenger
+from .context import Context
 
 class Dispatcher(object):
     def __init__(self, base_directory):
         self._log = Messenger()
-        self._set_base_directory(base_directory)
+        self._setup_context(base_directory)
         self._load_plugins()
 
-    def _set_base_directory(self, base_directory):
+    def _setup_context(self, base_directory):
         path = os.path.abspath(os.path.realpath(
             os.path.expanduser(base_directory)))
-        if os.path.exists(path):
-            self._base_directory = path
-        else:
+        if not os.path.exists(path):
             raise DispatchError('Nonexistent base directory')
+        self._context = Context(path)
 
     def dispatch(self, tasks):
         success = True
         for task in tasks:
             for action in task:
                 handled = False
+                if action == 'defaults':
+                    self._context.set_defaults(task[action]) # replace, not update
+                    handled = True
+                    # keep going, let other plugins handle this if they want
                 for plugin in self._plugins:
                     if plugin.can_handle(action):
                         try:
@@ -36,7 +40,7 @@ class Dispatcher(object):
         return success
 
     def _load_plugins(self):
-        self._plugins = [plugin(self._base_directory)
+        self._plugins = [plugin(self._context)
             for plugin in Plugin.__subclasses__()]
 
 class DispatchError(Exception):
diff --git a/dotbot/plugin.py b/dotbot/plugin.py
index a79639e..56d4da8 100644
--- a/dotbot/plugin.py
+++ b/dotbot/plugin.py
@@ -1,12 +1,13 @@
 from .messenger import Messenger
+from .context import Context
 
 class Plugin(object):
     '''
     Abstract base class for commands that process directives.
     '''
 
-    def __init__(self, base_directory):
-        self._base_directory = base_directory
+    def __init__(self, context):
+        self._context = context
         self._log = Messenger()
 
     def can_handle(self, directive):
diff --git a/plugins/clean.py b/plugins/clean.py
index 22ec450..dbd11af 100644
--- a/plugins/clean.py
+++ b/plugins/clean.py
@@ -36,7 +36,7 @@ class Clean(dotbot.Plugin):
         for item in os.listdir(os.path.expanduser(target)):
             path = os.path.join(os.path.expanduser(target), item)
             if not os.path.exists(path) and os.path.islink(path):
-                if self._in_directory(path, self._base_directory):
+                if self._in_directory(path, self._context.base_directory()):
                     self._log.lowinfo('Removing invalid link %s -> %s' %
                         (path, os.path.join(os.path.dirname(path), os.readlink(path))))
                     os.remove(path)
diff --git a/plugins/link.py b/plugins/link.py
index 3bb5686..30a77c9 100644
--- a/plugins/link.py
+++ b/plugins/link.py
@@ -17,25 +17,27 @@ class Link(dotbot.Plugin):
 
     def _process_links(self, links):
         success = True
+        defaults = self._context.defaults().get('link', {})
         for destination, source in links.items():
             source = os.path.expandvars(source)
             destination = os.path.expandvars(destination)
+            relative = defaults.get('relative', False)
+            force = defaults.get('force', False)
+            relink = defaults.get('relink', False)
+            create = defaults.get('create', False)
             if isinstance(source, dict):
                 # extended config
+                relative = source.get('relative', relative)
+                force = source.get('force', force)
+                relink = source.get('relink', relink)
+                create = source.get('create', create)
                 path = source['path']
-                relative = source.get('relative', False)
-                force = source.get('force', False)
-                relink = source.get('relink', False)
-                create = source.get('create', False)
-                if create:
-                    success &= self._create(destination)
-                if force:
-                    success &= self._delete(path, destination, force=True)
-                elif relink:
-                    success &= self._delete(path, destination, force=False)
             else:
-                relative = False
                 path = source
+            if create:
+                success &= self._create(destination)
+            if force or relink:
+                success &= self._delete(path, destination, force=force)
             success &= self._link(path, destination, relative)
         if success:
             self._log.info('All links have been set up')
@@ -79,7 +81,7 @@ class Link(dotbot.Plugin):
 
     def _delete(self, source, path, force):
         success = True
-        source = os.path.join(self._base_directory, source)
+        source = os.path.join(self._context.base_directory(), source)
         if ((self._is_link(path) and self._link_destination(path) != source) or
                 (self._exists(path) and not self._is_link(path))):
             fullpath = os.path.expanduser(path)
@@ -110,7 +112,7 @@ class Link(dotbot.Plugin):
         Returns true if successfully linked files.
         '''
         success = False
-        source = os.path.join(self._base_directory, source)
+        source = os.path.join(self._context.base_directory(), source)
         if (not self._exists(link_name) and self._is_link(link_name) and
                 self._link_destination(link_name) != source):
             self._log.warning('Invalid link %s -> %s' %
diff --git a/plugins/shell.py b/plugins/shell.py
index a2d9c1a..f321ca3 100644
--- a/plugins/shell.py
+++ b/plugins/shell.py
@@ -18,17 +18,18 @@ class Shell(dotbot.Plugin):
 
     def _process_commands(self, data):
         success = True
+        defaults = self._context.defaults().get('shell', {})
         with open(os.devnull, 'w') as devnull:
             for item in data:
                 stdin = stdout = stderr = devnull
                 if isinstance(item, dict):
                     cmd = item['command']
                     msg = item.get('description', None)
-                    if item.get('stdin', False) is True:
+                    if item.get('stdin', defaults.get('stdin', False)) is True:
                         stdin = None
-                    if item.get('stdout', False) is True:
+                    if item.get('stdout', defaults.get('stdout', False)) is True:
                         stdout = None
-                    if item.get('stderr', False) is True:
+                    if item.get('stderr', defaults.get('stderr', False)) is True:
                         stderr = None
                 elif isinstance(item, list):
                     cmd = item[0]
@@ -41,7 +42,7 @@ class Shell(dotbot.Plugin):
                 else:
                     self._log.lowinfo('%s [%s]' % (msg, cmd))
                 ret = subprocess.call(cmd, shell=True, stdin=stdin, stdout=stdout,
-                    stderr=stderr, cwd=self._base_directory)
+                    stderr=stderr, cwd=self._context.base_directory())
                 if ret != 0:
                     success = False
                     self._log.warning('Command [%s] failed' % cmd)
diff --git a/test/tests/defaults.bash b/test/tests/defaults.bash
new file mode 100644
index 0000000..595f950
--- /dev/null
+++ b/test/tests/defaults.bash
@@ -0,0 +1,34 @@
+test_description='defaults setting works'
+. '../test-lib.bash'
+
+test_expect_success 'setup' '
+echo "apple" > ${DOTFILES}/f &&
+echo "grape" > ~/f &&
+ln -s ~/f ~/.f
+'
+
+test_expect_failure 'run-fail' '
+run_dotbot <<EOF
+- link:
+    ~/.f: f
+EOF
+'
+
+test_expect_failure 'test-fail' '
+grep "apple" ~/.f
+'
+
+test_expect_success 'run' '
+run_dotbot <<EOF
+- defaults:
+    link:
+      relink: true
+
+- link:
+    ~/.f: f
+EOF
+'
+
+test_expect_success 'test' '
+grep "apple" ~/.f
+'