helper: move string_sanitize() to the only place where it is used

1 files changed, 38 insertions, 1 deletions

diff --git a/alot/buffers/envelope.py b/alot/buffers/envelope.py
index ada8791c..83a3c57b 100644
--- a/alot/buffers/envelope.py
+++ b/alot/buffers/envelope.py
@@ -9,8 +9,45 @@ from ..settings.const import settings
 from ..widgets.globals import HeadersList
 from ..widgets.globals import AttachmentWidget
 from ..helper import shorten_author_string
-from ..helper import string_sanitize
 
+def string_sanitize(string, tab_width=8):
+    r"""
+    strips, and replaces non-printable characters
+
+    :param tab_width: number of spaces to replace tabs with. Read from
+                      `globals.tabwidth` setting if `None`
+    :type tab_width: int or `None`
+
+    >>> string_sanitize(' foo\rbar ', 8)
+    ' foobar '
+    >>> string_sanitize('foo\tbar', 8)
+    'foo     bar'
+    >>> string_sanitize('foo\t\tbar', 8)
+    'foo             bar'
+    """
+
+    string = string.replace('\r', '')
+
+    lines = list()
+    for line in string.split('\n'):
+        tab_count = line.count('\t')
+
+        if tab_count > 0:
+            line_length = 0
+            new_line = list()
+            for i, chunk in enumerate(line.split('\t')):
+                line_length += len(chunk)
+                new_line.append(chunk)
+
+                if i < tab_count:
+                    next_tab_stop_in = tab_width - (line_length % tab_width)
+                    new_line.append(' ' * next_tab_stop_in)
+                    line_length += next_tab_stop_in
+            lines.append(''.join(new_line))
+        else:
+            lines.append(line)
+
+    return '\n'.join(lines)
 
 class EnvelopeBuffer(Buffer):
     """message composition mode"""