Added whitespace stripper filter. The set of space-preserved elements is <pre>, <textarea> and RCDATA elements (i.e. <script> and <style>).

tbroyer · tbroyer · commit 576fa7e30b3a · 2007-06-09T18:42:18.000Z
--HG--
extra : convert_revision : svn%3Aacbfec75-9323-0410-a652-858a13e371e0/trunk%40690
diff --git a/src/filters/whitespace.py b/src/filters/whitespace.py
@@ -0,0 +1,40 @@
+try:
+    frozenset
+except NameError:
+    # Import from the sets module for python 2.3
+    from sets import ImmutableSet as frozenset
+
+import re
+
+import _base
+from constants import rcdataElements
+
+from constants import spaceCharacters
+spaceCharacters = u"".join(spaceCharacters)
+
+class Filter(_base.Filter):
+    
+    spacePreserveElements = frozenset(["pre", "textarea"] + list(rcdataElements))
+    
+    def __iter__(self):
+        preserve = False
+        for token in _base.Filter.__iter__(self):
+            type = token["type"]
+            if not preserve and type == "StartTag" \
+              and token["name"] in self.spacePreserveElements:
+                preserve = True
+
+            elif type == "EndTag":
+                preserve = False
+
+            elif not preserve and type == "SpaceCharacters":
+                continue
+
+            elif not preserve and type == "Characters":
+                token["data"] = collapse_spaces(token["data"])
+
+            yield token
+
+def collapse_spaces(text):
+    return re.compile(u"[%s]+" % spaceCharacters).sub(' ', text)
+
