SyntaxError: invalid syntax about chameleon

[malthe]

Must be a bug in http://pypi.python.org/pypi/sourcecodegen (which generates Python source code from a Python 2.4 AST in order for us to use RestrictedPython).

How can I reproduce this locally? Is the an open-source package you're trying to use?

[rpatterson]

Oh, sorry, missed the request for more info.

No, unfortunately, this is in client code. I have two tests that fail with this error. Both of them are testbrowser tests that create a custom AT content type both of which use the default AT view and edit templates.

Some time with pdb shows me that this error comes from using Products.ATBackRef: https://dev.plone.org/archetypes/browser/MoreFieldsAndWidgets/ATBackRef/trunk/src/Products/ATBackRef/skins/ATBackRef/backreferencebrowserwidget.pt?rev=13257#L57

tal:define="foo python:refs.sort(lambda x,y: cmp(x.order, y.order))"

[rpatterson]

I worked around this:

https://dev.plone.org/archetypes/changeset/13739

But it sure looks like Chameleon might not support lambdas. I did a grep of all my client project full omelets and didn't find any other cases of lambdas in templates. Still, I'm sure ATBackRef isn't the only one which did. So this should probably be fixed or lambdas should be documented as an exception to Chameleon's claim of compatibility.