bug#59314: 29.0.50; EUDC and message-mode header completion

[Thomas Fitzsimmons <fitzsim@fitzsim.org>]

Alexander Adolf <alexander.adolf@condition-alpha.com> writes:

> Thomas Fitzsimmons <fitzsim@fitzsim.org> writes:
>
>> [...]
>> The eventual message.el refactoring could work.  But for now, for Emacs
>> 29.1, let's focus on what's already in message.el, which is a lot!
>
> Fully agree.
>
>> In particular, I'm trying to make this recipe do something useful, with
>> a minimal patch to message.el.
>> [...]
>
> Looking at this now.

Great, thank you.

> While I set this up: What's your value of the variable
> `completion-styles` during this test?

I didn't change it, so it should be the default, which looks to be:
(basic partial-completion emacs22)

> Does changing `completion-styles` to '(substring partial-completion)
> for the test change the result and outcome?

I'll try this later today.

Thanks,
Thomas