1 files changed, 43 insertions, 30 deletions
diff --git a/sphinx/websupport/storage/differ.py b/sphinx/websupport/storage/differ.py
index c82ba7427..068d7e6fc 100644
--- a/sphinx/websupport/storage/differ.py
+++ b/sphinx/websupport/storage/differ.py
@@ -14,39 +14,18 @@ from cgi import escape
 from difflib import Differ
 
 class CombinedHtmlDiff(object):
-
+    """Create an HTML representation of the differences between two pieces
+    of text.
+    """
     highlight_regex = re.compile(r'([\+\-\^]+)')
 
-    def _highlight_text(self, text, next, tag):
-        next = next[2:]
-        new_text = []
-        start = 0
-        for match in self.highlight_regex.finditer(next):
-            new_text.append(text[start:match.start()])
-            new_text.append('<%s>' % tag)
-            new_text.append(text[match.start():match.end()])
-            new_text.append('</%s>' % tag)
-            start = match.end()
-        new_text.append(text[start:])
-        return ''.join(new_text)
-
-    def _handle_line(self, line, next=None):
-        prefix = line[0]
-        text = line[2:]
-
-        if prefix == ' ':
-            return text
-        elif prefix == '?':
-            return ''
-        
-        if next is not None and next[0] == '?':
-            tag = 'ins' if prefix == '+' else 'del'
-            text = self._highlight_text(text, next, tag)
-        css_class = 'prop_added' if prefix == '+' else 'prop_removed'
-        
-        return '<span class="%s">%s</span>\n' % (css_class, text.rstrip())
-
     def make_html(self, source, proposal):
+        """Return the HTML representation of the differences between
+        `source` and `proposal`.
+
+        :param source: the original text
+        :param proposal: the proposed text
+        """
         proposal = escape(proposal)
 
         differ = Differ()
@@ -64,3 +43,37 @@ class CombinedHtmlDiff(object):
                 self._handle_line(line)
                 break
         return ''.join(html)
+
+    def _handle_line(self, line, next=None):
+        """Handle an individual line in a diff."""
+        prefix = line[0]
+        text = line[2:]
+
+        if prefix == ' ':
+            return text
+        elif prefix == '?':
+            return ''
+        
+        if next is not None and next[0] == '?':
+            tag = 'ins' if prefix == '+' else 'del'
+            text = self._highlight_text(text, next, tag)
+        css_class = 'prop_added' if prefix == '+' else 'prop_removed'
+        
+        return '<span class="%s">%s</span>\n' % (css_class, text.rstrip())
+
+    def _highlight_text(self, text, next, tag):
+        """Highlight the specific changes made to a line by adding
+        <ins> and <del> tags.
+        """
+        next = next[2:]
+        new_text = []
+        start = 0
+        for match in self.highlight_regex.finditer(next):
+            new_text.append(text[start:match.start()])
+            new_text.append('<%s>' % tag)
+            new_text.append(text[match.start():match.end()])
+            new_text.append('</%s>' % tag)
+            start = match.end()
+        new_text.append(text[start:])
+        return ''.join(new_text)
+