Jacob Keller <jacob.e.keller@xxxxxxxxx> writes:
> From: Jacob Keller <jacob.keller@xxxxxxxxx>
>
> Teach git diff --no-index the ability to exclude files by wildmatch
> pattern when recursing through directories. The '--exclude' option
> builds up a string list containing the patterns. These are checked with
> wildmatch() in the read_directory_contents function. If any pattern
> matches, then the file is not included in the directory contents.
A quite natural question that comes to mind is:
How would we do this for the normal "git diff" that is not the
bolted on '--no-index' mode?
but ...
> The --exclude option is only supported by the --no-index mode. Standard
> diff modes support negative pathspecs which is more powerful. I tried to
> see if there was a way to add support for negative pathspecs themselves,
> but haven't yet figured out if this is possible.
... of course you have thought about it already. I do agree with
you that we should figure out how and teach this mode to also use
pathspec, not necessarily only the negative ones but positive ones.
After all,
$ git diff --no-index [<option>...] dirA dirB
is like running
$ diff -r [<option>...] dirA dirB
after preparing these two directories like so:
$ git archive revA | ( mkdir dirA && tar Cxf dirA - )
$ git archive revB | ( mkdir dirB && tar Cxf dirB - )
Hence it is natural for users to expect that anything you can do
with
$ git diff revA revB
should be doable, in
$ git diff --no-index dirA dirB
and vice versa. And as you said, when comparing two revisions,
you'd use pathspec for this kind of thing.
$ git diff revA revB -- Documentation/ t/ ':!po/'
So, I pretty much agree with the need to be able to exclude some
parts of the tree(s) from comparison in "diff --no-index" mode, but
I doubt it is a good idea to tell what to exclude the "--no-index"
mode in a completely different way.
The last time I looked at it, I got an impression that the command
line argument parsing of "git diff --no-index" was messy (which is
sort of inevitable, since unlike the normal "git diff", it can
compare more than just two "collections"---it can take two paths to
regular files, for example, and in such a case pathspec arguments
can play no role), so teaching it pathspec parsing might be a bit of
work, though.
Thanks for starting an interesting topic.
