Re: [PATCH v3] config: Add new option to open an editor.

[Junio C Hamano <gitster@pobox.com>]

Felipe Contreras <felipe.contreras@gmail.com> writes:

>>> I think it should, how expensive would it be to call
>>> git_config(git_default_config, NULL) when it has been loaded already?
>>
>> We would not need the complete git_default_config(), would we?
>
> Nope, just core.editor. But I don't know how to load only that.

The most expensive part is to actually open and parse the files into
tokens, not strcmp/prefixcmp the parsed tokens and flipping internal bits
and storing value in const char * variables.

But you need to be careful about correctness issues.  I do not want
launch_editor() to run git_config().  The caller, other than the caller
you happen to be interested in this thread, may already have read the
config and overrode some of the bits with what was given from the command
line.  Calling git_config() overwrite the bits and will break these
callers.

I think the right thing to do is to call git_config() immediately before
you call launch_editor() in your patch.