id	summary	reporter	owner	description	type	status	component	version	severity	resolution	keywords	cc	stage	has_patch	needs_docs	needs_tests	needs_better_patch	easy	ui_ux
12995	"""source"" exception attribute no longer handled properly by debug exception handler"	Glenn Maynard	nobody	"The ""source"" attribute on exceptions handled by the debug view was very handy; I set it in my own custom templating system (which coexists with Django's) and it automatically showed up in errors generated by Django's, complete with line numbers, just like they do for when Django templates set that attribute.  Duck typing made this work implicitly, which was extremely useful--that's how duck typing is supposed to work.

r12586 broke this, adding an isinstance check which makes it so only errors from Django's own templates can use this feature.  This doesn't make sense; duck typing was the correct approach here.

Please revert r12586; that was an unnecessarily destructive change.  If you're having namespace collisions, then use a less generic name (""source_with_lines"" or something like that).
"	New feature	closed	Template system	dev	Normal	fixed			Accepted	0	0	0	0	0	0