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

[Dmitry Gutov <dmitry@gutov.dev>]

On 18/09/2023 09:51, Juri Linkov wrote:
>>> 'C-x p p C-x v L' to see a vc log in another project, and
>>> 'C-x p p C-x v d' to open vc-dir, etc.
>> All right, so we also want to support non-project commands. And you wanted
>> to use a common approach for both.
>>
>> What if we handle them differently, though? For "project" commands (those
>> that internally call project-current) we can set one variable, and for the
>> rest -- alter default-directory. Then restore the previous value in
>> post-command.
>>
>> The detection of "project commands" could work like this:
>>
>> - Is it in one of the special maps? E.g. in project-prefix-map. Or maybe
>>    it's in project-switch-commands.
>> - Does the function name start with 'project-'?
>> - Finally, for user-defined commands we could also introduce a property
>>    'project-command-p', although the distinction between using
>>    project-current-directory-override vs default-directory will not be
>>    important for every such command, so maybe being this thorough is not too
>>   important.
> Sorry, I don't understand how 'C-x p p' could read the user's mind
> whether the user afterwards will type a key for a project command
> or a non-project command?  And depending on user's intention will
> either set project-current-directory-override or default-directory.

Ah, I forgot that in the general case we don't read the sequence, find 
the command and do the thing. We leave the event loop up to Emacs.

What about pre-command-hook? this-command will already be set by then.