bug#47388: 27.1; eldoc-documentation-function is ignore in updated eldoc

["João Távora" <joaotavora@gmail.com>]

"Basil L. Contovounesios" <contovob@tcd.ie> writes:

> Alex Branham <alex.branham@gmail.com> writes:
>
>> Emacs 27.1 ships with eldoc that defines eldoc-documentation-function as
>> #'ignore. If users install eglot from ELPA, this pulls in an updated
>> eldoc that attempts to redefine eldoc-documentation-function. However,
>> the value does not change (since eldoc-documentation-function is already
>> bound, defcustom does not update it when called in
>> eldoc--documentation-strategy-defcustom) so the value is still ignore,
>> meaning users get:
>>
>>     There is no ElDoc support in this buffer
>>
>> since eldoc-documentation-function is #'ignore, regardless of the value
>> of eldoc-documentation-functions.
>>
>> Here's the bug report we received with the original issue:
>> https://github.com/emacs-ess/ESS/issues/1130
>
> Thanks, CCing João.

Thanks Basil, Alex,

Alex, exactly under what circunstances do you see that "There is no
ElDoc support in this buffer"?  In what buffer, doing what?  I
appreciate that you have investigated the implementation, but I need to
be able to understand -- and potentially reproduce -- the problem
exactly as it happened to you, so please provide as clear a recipe as
possible, perhaps starting with "downloaded Emacs 27.1, then cleared my
ELPA directory, ..., installed Eglot from xyz, ..., ".

Meanwhile (but not excluding the earlier valuable exercise), can you
show the output of:

  C-h v eldoc-documentation-function RET
  C-h v eldoc-documentation-strategy RET

?

Thanks again,
João