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

[Juri Linkov]

>>>>> C-x p p some/project RET C-x v +
>>>>>
>>>>> because I wanted to immediately pull that project.  Intuitively it made
>>>>> sense to me that that should work, it would be nice if it did actually
>>>>> work.
>>>> This should be possible to implement by using 'set-transient-map'.
>>>>
>>>>> (Tangential further thought: I wonder if we could make C-x p work as a
>>>>> prefix for all commands automatically, so for example C-x p C-x C-j
>>>>> would open the project root, C-x p M-& would run a shell command in the
>>>>> root, etc.  That would be neat.)
>>>> IOW, like 'C-x p p' but without asking for another project.  Doable as 
>>>> well.
>>>
>>> That sounds like a cool potential addition, just we all need to keep in
>>> mind that not every command will be 100% compatible with the approach.
>> Why not every command?  For example, 100% commands are compatible with
>> 'C-x t t.'
>>
>>> One example is the bug#58784 where changing default-directory made
>>> project-switch-to-buffer behave incorrectly. Maybe there are some less
>>> subtle examples as well.
>> 'display-buffer-override-next-command' already solved these problems.
>> So a similar function could remember 'project-current-directory-override'
>> for the next command.
>
> But we were talking about "regular" commands, right? Those don't know
> anything about project-current-directory-override.

Any command indeed.  They should use the temporarily set default-directory.

> So we'd bind default-directory, and that's where the problem could come
> from. Hopefully, only in rare cases, though.

Naturally, this needs more testing.