Do not rely on `nodes.Node.traverse()` returning a "list" instance.

While the current implementation actually returns a list of nodes,
the docstring specifies only: "Return an iterable ...".

git-svn-id: http://svn.code.sf.net/p/docutils/code/trunk@8387 929543f6-e4f2-0310-98a6-ba3bd3dd1d04

4 files changed, 32 insertions, 28 deletions

diff --git a/docutils/docutils/transforms/references.py b/docutils/docutils/transforms/references.py
index d2490a23d..4e8eb16c9 100644
--- a/docutils/docutils/transforms/references.py
+++ b/docutils/docutils/transforms/references.py
@@ -663,7 +663,7 @@ class Substitutions(Transform):
     def apply(self):
         defs = self.document.substitution_defs
         normed = self.document.substitution_names
-        subreflist = self.document.traverse(nodes.substitution_reference)
+        subreflist = list(self.document.traverse(nodes.substitution_reference))
         nested = {}
         for ref in subreflist:
             refname = ref['refname']
diff --git a/docutils/docutils/transforms/universal.py b/docutils/docutils/transforms/universal.py
index 8e71842b1..aca1af3e4 100644
--- a/docutils/docutils/transforms/universal.py
+++ b/docutils/docutils/transforms/universal.py
@@ -144,7 +144,7 @@ class FilterMessages(Transform):
     default_priority = 870
 
     def apply(self):
-        for node in self.document.traverse(nodes.system_message):
+        for node in list(self.document.traverse(nodes.system_message)):
             if node['level'] < self.document.reporter.report_level:
                 node.parent.remove(node)
 
@@ -176,7 +176,7 @@ class StripComments(Transform):
 
     def apply(self):
         if self.document.settings.strip_comments:
-            for node in self.document.traverse(nodes.comment):
+            for node in list(self.document.traverse(nodes.comment)):
                 node.parent.remove(node)
 
 
@@ -191,27 +191,31 @@ class StripClassesAndElements(Transform):
     default_priority = 420
 
     def apply(self):
-        if not (self.document.settings.strip_elements_with_classes
-                or self.document.settings.strip_classes):
+        if self.document.settings.strip_elements_with_classes:
+            self.strip_elements = set(
+                self.document.settings.strip_elements_with_classes)
+            # Iterate over a list as removing the current node
+            # corrupts the iterator returned by `traverse`:
+            for node in list(self.document.traverse(self.check_classes)):
+                node.parent.remove(node)
+
+        if not self.document.settings.strip_classes:
             return
-        # prepare dicts for lookup (not sets, for Python 2.2 compatibility):
-        self.strip_elements = dict(
-            [(key, None)
-             for key in (self.document.settings.strip_elements_with_classes
-                         or [])])
-        self.strip_classes = dict(
-            [(key, None) for key in (self.document.settings.strip_classes
-                                     or [])])
-        for node in self.document.traverse(self.check_classes):
-            node.parent.remove(node)
+        strip_classes = self.document.settings.strip_classes
+        for node in self.document.traverse(nodes.Element):
+            for class_value in strip_classes:
+                try:
+                    node['classes'].remove(class_value)
+                except ValueError:
+                    pass
 
     def check_classes(self, node):
-        if isinstance(node, nodes.Element):
-            for class_value in node['classes'][:]:
-                if class_value in self.strip_classes:
-                    node['classes'].remove(class_value)
-                if class_value in self.strip_elements:
-                    return 1
+        if not isinstance(node, nodes.Element):
+            return False
+        for class_value in node['classes'][:]:
+            if class_value in self.strip_elements:
+                return True
+        return False
 
 
 class SmartQuotes(Transform):
diff --git a/docutils/docutils/writers/latex2e/__init__.py b/docutils/docutils/writers/latex2e/__init__.py
index 50159230c..6c42180f1 100644
--- a/docutils/docutils/writers/latex2e/__init__.py
+++ b/docutils/docutils/writers/latex2e/__init__.py
@@ -1815,13 +1815,11 @@ class LaTeXTranslator(nodes.NodeVisitor):
         if self._use_latex_citations:
             followup_citation = False
             # check for a following citation separated by a space or newline
-            next_siblings = node.traverse(descend=False, siblings=True,
-                                          include_self=False)
-            if len(next_siblings) > 1:
-                next = next_siblings[0]
-                if (isinstance(next, nodes.Text) and
-                    next.astext() in (' ', '\n')):
-                    if next_siblings[1].__class__ == node.__class__:
+            sibling = node.next_node(descend=False, siblings=True)
+            if (isinstance(sibling, nodes.Text) 
+                and sibling.astext() in (' ', '\n')):
+                sibling2 = sibling.next_node(descend=False, siblings=True)
+                if isinstance(sibling2, nodes.citation_reference):
                         followup_citation = True
             if followup_citation:
                 self.out.append(',')
diff --git a/docutils/test/test_transforms/test_strip_comments.py b/docutils/test/test_transforms/test_strip_comments.py
index 436fbe94f..12226dee0 100755
--- a/docutils/test/test_transforms/test_strip_comments.py
+++ b/docutils/test/test_transforms/test_strip_comments.py
@@ -31,6 +31,8 @@ Title
 =====
 
 Paragraph.
+
+.. second comment
 """,
 """\
 <document source="test data">