Print original exception when an unknown error occurs in template

[nnorwitz@…]

We had a problem when we updated a Model, but not the DB. Loading the template failed and we got a useless error message because of catching the original exception and wrapping it. Only the TemplateSyntaxError was printed, not the original exception which was very misleading. This was with 0.91, but HEAD has the same issue. Below is a patch that fixes the problem. I didn't see a way to upload a file as a patch.

--- template/init.py.orig 2006-05-12 11:14:27.000000000 -0700
+++ template/init.py 2006-05-12 11:14:00.000000000 -0700
@@ -90,7 +90,20 @@

builtins = []

class TemplateSyntaxError(Exception):

• pass

+ def str(self):
+ try:
+ import cStringIO as StringIO
+ except ImportError:
+ import StringIO
+ output = StringIO.StringIO()
+ output.write(Exception.str(self))
+ # Check if we wrapped an exception and print that too.
+ if hasattr(self, 'exc_info'):
+ import traceback
+ output.write('\n\nOriginal ')
+ e = self.exc_info
+ traceback.print_exception(e[0], e[1], e[2], 500, output)
+ return output.getvalue()

class ContextPopException(Exception):

"pop() has been called more times than push()"

[Adrian Holovaty]

(In [2906]) Fixed #1852 -- Improved TemplateSyntaxError to display the original exception if str() of the exception raises an exception in itself. Thanks, nnorwitz@…