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
25942	TypedChoiceField.has_changed behaviour has changed between 1.8 and 1.9	Arthur Vuillard	nobody	"We've met a strange bug with Django 1.9 on TypedChoiceField.has_changed.

We encountered the bug when using a TypedChoiceField in a form of a formset. When we have an empty extra form, and we submit all the form, the submitted form is not validated due to some ""changes"" made to the TypedChoiceFields.

The excepted behavior would be to save the formset data without treating that extra form.

I finally found that the method has_changed of a field has been modified from 1.8, and calls self._coerce for the initial value. By removing it, my use case now works like expected.

I attach to this ticket a unit test that reproduces my case. "	Bug	closed	Forms	1.9	Release blocker	fixed			Ready for checkin	1	0	0	0	0	0