bug#63648: 29.0.90; project.el: with switch-use-entire-map, switch-project errors on non-project commands

[sbaugh]

Juri Linkov <juri@linkov.net> writes:

>>>>> 1. the current buffer should remain the same for the next command;
>>>>> 2. the buffer-local value of 'default-directory' should remain the same;
>>>>> 3. the next command should have a new value of 'default-directory'.
>>>>>
>>>>> I see no way to satisfy all these requirements.
>>>>
>>>> Except adding a variable like 'project-current-directory-override'
>>>> somewhere inside 'command_loop_1'.
>>> And indeed with the following patch replacing the current definition of
>>> 'project-switch-project' with just:
>>>    (defun project-switch-project (dir)
>>>      (interactive (list (funcall project-prompter)))
>>>      (setq next-default-directory dir))
>>
>> Note that we'd need to keep the previous implementation for a number of
>> years anyway, to retain compatibility with older emacsen.
>
> Then some version-depending condition could be added.
>
>>> 'C-x p p (select project ...) RET M-& pwd RET' confirms that
>>> the command runs in the selected project directory.
>>> Whereas the original buffer keeps its previous buffer-local value
>>> of 'default-directory'.
>>
>> I suggest you bring up this feature addition on emacs-devel, or otherwise
>> wait for a review from Eli, at least.
>>
>> It's not a big addition, but it's a distinct new feature (the
>> next-default-directory var).
>
> Indeed, such code addition better to be discussed on emacs-devel.

Did this end up being discussed on emacs-devel?  I am still quite
interested in this feature.

> But first need to ensure that it works with 'C-x p p'.
> Currently it works with keys from the global map such as
> 'C-x p p M-& pwd RET', but not with keys from 'project-prefix-map', e.g.
> 'C-x p p f'.  Maybe in addition to (setq next-default-directory dir)
> also need to use 'set-transient-map' with 'project-prefix-map'.