From 0b70a32efedb1d0fe8789e6278db52b0973f1700 Mon Sep 17 00:00:00 2001
From: Georg Brandl <georg@python.org>
Date: Sun, 3 Jan 2010 11:42:15 +0100
Subject: [PATCH] Ignore images in section titles when generating link
 captions. (Otherwise, the "alt" text leaks into the caption, and docutils
 automatically assigns an alt text to images in substitutions.)

---
 CHANGES                 |  2 ++
 sphinx/environment.py   | 10 +++++-----
 sphinx/util/__init__.py |  8 ++++++++
 3 files changed, 15 insertions(+), 5 deletions(-)

diff --git a/CHANGES b/CHANGES
index b6a2d3843..177344642 100644
--- a/CHANGES
+++ b/CHANGES
@@ -1,6 +1,8 @@
 Release 0.6.4 (in development)
 ==============================
 
+* Ignore images in section titles when generating link captions.
+
 * #310: support exception messages in the ``testoutput`` blocks of
   the ``doctest`` extension.
 
diff --git a/sphinx/environment.py b/sphinx/environment.py
index 83c97d5f4..b83b2fbf0 100644
--- a/sphinx/environment.py
+++ b/sphinx/environment.py
@@ -37,7 +37,7 @@ from docutils.transforms.parts import ContentsFilter
 
 from sphinx import addnodes
 from sphinx.util import movefile, get_matching_docs, SEP, ustrftime, \
-     docname_join, FilenameUniqDict, url_re
+     docname_join, FilenameUniqDict, url_re, clean_astext
 from sphinx.errors import SphinxError
 from sphinx.directives import additional_xref_types
 
@@ -820,11 +820,11 @@ class BuildEnvironment:
                           node.line)
             self.anonlabels[name] = docname, labelid
             if node.tagname == 'section':
-                sectname = node[0].astext() # node[0] == title node
+                sectname = clean_astext(node[0]) # node[0] == title node
             elif node.tagname == 'figure':
                 for n in node:
                     if n.tagname == 'caption':
-                        sectname = n.astext()
+                        sectname = clean_astext(n)
                         break
                 else:
                     continue
@@ -1074,7 +1074,7 @@ class BuildEnvironment:
                         # toctree originates
                         ref = toctreenode['parent']
                         if not title:
-                            title = self.titles[ref].astext()
+                            title = clean_astext(self.titles[ref])
                         reference = nodes.reference('', '',
                                                     refuri=ref,
                                                     anchorname='',
@@ -1222,7 +1222,7 @@ class BuildEnvironment:
                             # reference with explicit title
                             caption = node.astext()
                         else:
-                            caption = self.titles[docname].astext()
+                            caption = clean_astext(self.titles[docname])
                         innernode = nodes.emphasis(caption, caption)
                         newnode = nodes.reference('', '')
                         newnode['refuri'] = builder.get_relative_uri(
diff --git a/sphinx/util/__init__.py b/sphinx/util/__init__.py
index 3cf58e0ef..59589b6d9 100644
--- a/sphinx/util/__init__.py
+++ b/sphinx/util/__init__.py
@@ -442,6 +442,14 @@ def copy_static_entry(source, target, builder, context={}):
         shutil.copytree(source, target)
 
 
+def clean_astext(node):
+    """Like node.astext(), but ignore images."""
+    node = node.deepcopy()
+    for img in node.traverse(docutils.nodes.image):
+        img['alt'] = ''
+    return node.astext()
+
+
 # monkey-patch Node.traverse to get more speed
 # traverse() is called so many times during a build that it saves
 # on average 20-25% overall build time!