[Zope3-checkins] SVN: Zope3/branches/3.3/src/zope/tales/ Fix http://www.zope.org/Collectors/Zope3-dev/635:

[Philipp von Weitershausen]

Log message for revision 68279:
  Fix http://www.zope.org/Collectors/Zope3-dev/635:
    TALES PathExpr doesn't calls old style classes
  

Changed:
  U   Zope3/branches/3.3/src/zope/tales/expressions.py
  U   Zope3/branches/3.3/src/zope/tales/tests/test_expressions.py

-=-
Modified: Zope3/branches/3.3/src/zope/tales/expressions.py
===================================================================
--- Zope3/branches/3.3/src/zope/tales/expressions.py	2006-05-25 17:49:12 UTC (rev 68278)
+++ Zope3/branches/3.3/src/zope/tales/expressions.py	2006-05-25 17:50:09 UTC (rev 68279)
@@ -15,7 +15,7 @@
 
 $Id$
 """
-import re
+import re, types
 
 from zope.interface import implements
 from zope.tales.tales import _valid_name, _parse_expr, NAME_RE, Undefined
@@ -194,8 +194,16 @@
         if self._name == 'nocall':
             return ob
 
-        # Call the object if it is callable.
-        if hasattr(ob, '__call__'):
+        # Call the object if it is callable.  Note that checking for
+        # callable() isn't safe because the object might be security
+        # proxied (and security proxies report themselves callable, no
+        # matter what the underlying object is).  We therefore check
+        # for the __call__ attribute, but not with hasattr as that
+        # eats babies, err, exceptions.  In addition to that, we
+        # support calling old style classes which don't have a
+        # __call__.
+        if (getattr(ob, '__call__', _marker) is not _marker
+            or isinstance(ob, types.ClassType)):
             return ob()
         return ob
 

Modified: Zope3/branches/3.3/src/zope/tales/tests/test_expressions.py
===================================================================
--- Zope3/branches/3.3/src/zope/tales/tests/test_expressions.py	2006-05-25 17:49:12 UTC (rev 68278)
+++ Zope3/branches/3.3/src/zope/tales/tests/test_expressions.py	2006-05-25 17:50:09 UTC (rev 68279)
@@ -115,6 +115,13 @@
         else:
             self.fail('Engine accepted first subpath element as dynamic')
             
+    def testOldStyleClassIsCalled(self):
+        class AnOldStyleClass:
+            pass
+        self.context.vars['oldstyleclass'] = AnOldStyleClass
+        expr = self.engine.compile('oldstyleclass')
+        self.assert_(isinstance(expr(self.context), AnOldStyleClass))
+            
     def testString(self):
         expr = self.engine.compile('string:Fred')
         context=self.context