Could you add a test based on your test code in #3327 ?

Here it is. I created a new test file, I'm not sure if I shouldn't have put it in test_axes.py (or even somewhere else).

Looks great. I would probably put it in test_text

Well, I can do that if you want, but it's really an issue in _AxesBase that created the Text instances of each title by passing the same FontProperty object (which then gets updated during an actual Axes.set_title() call).
Tell me and I'll do either way.
By the way, are there some guidelines/conventions to name the tests (didn't find them so far)?

One of the core developers should probably decide on that @tacaswell @mdboom what do you say?
I don't think there any specific guidelines. I was going by the similarity to the test_titles in test_text which tests left and right loc of titles.

I am a little bit hesitant about this fix (at least, I wonder if it is as
complete as it should be). We currently have just one rcParam for titles.
How does this change behavior for those who may be using an rcparam context
manager to change the properties of the title? I am guessing that it should
work as expected, but I haven't dug down to see if that is the case.

On Wed, Jul 30, 2014 at 11:33 AM, Jens H Nielsen [email protected]
wrote:

One of the core developers should probably decide on that @tacaswell
https://github.com/tacaswell @mdboom https://github.com/mdboom what
do you say?
I don't think there any specific guidelines. I was going by the similarity
to the test_titles in test_text which tests left and right loc of titles.

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#3328 (comment)
.

I'm not too familiar with rcParam context managers but right now (unpatched) when calling cla() on a _AxesBase instance (which is done in the middle of __init__), a single FontProperty object is created using values from rcParam (axes/_base.py:898). This object was then passed on the three Text instances which means it was shared between them.
My patch is just copying this FontProperty object (after it's filled) so that manually changing some font property on one title is not propagated to the other two.
So, if my understanding of rcParam as a repository for default settings is correct, I believe there should be no issue.

Only concern is that updating the axes property manager resulting in the title updating could be seen as a feature, not a bug.

This should probably get an entry in api_chages.rst at a minimum.

I would lean toward putting it in test_text.py.

We probably only need the png version of this test and can you modify the test to include the right title too?

When you change the tests please squash the commits so that we don't end up with multiple versions of these images in the repo.

I'm sorry, I didn't get that: how would you update the axes property manager to update the title?
(I didn't find that in the code but it's a bit huge...)

By exactly the same mechanism that cause the bug, the properties are consulted at draw time

Closed as this is taken care of in #3335 .