Merge branch 'error_handler' of https://bitbucket.org/designst/mako/overview into t

mako/compat.py

@@ -68,6 +68,18 @@ else:
             fp.close()
 
 
+if py3k:
+    def reraise(tp, value, tb=None, cause=None):
+        if cause is not None:
+            value.__cause__ = cause
+        if value.__traceback__ is not tb:
+            raise value.with_traceback(tb)
+        raise value
+else:
+    exec("def reraise(tp, value, tb=None, cause=None):\n"
+            "    raise tp, value, tb\n")
+
+
 def exception_as():
     return sys.exc_info()[1]
 

mako/runtime.py

@@ -863,7 +863,7 @@ def _render_error(template, context, error):
     if template.error_handler:
         result = template.error_handler(context, error)
         if not result:
-            raise error
+            compat.reraise(*sys.exc_info())
     else:
         error_template = exceptions.html_error_template()
         if context._outputting_as_unicode: