Re: [PATCH v2] checkout: add --no-widen for restoring files in sparse checkout mode

[Jonathan Nieder <jrnieder@gmail.com>]

Hi,

Nguyễn Thái Ngọc Duy wrote:

> "git checkout -- <paths>" is usually used to restore all modified
> files in <paths>. In sparse checkout mode, this command is overloaded
> with another meaning: to add back all files in <paths> that are
> excluded by sparse patterns.
>
> Add "--no-widen" option to do what normal mode does: restore all
> modified files and nothing else.

In an ideal world, I would like "git checkout --widen" to modify the
.git/info/sparse-checkout file, to be able to do:

	git clone --sparse-checkout=Documentation git://repo.or.cz/git.git
	cd git
	git checkout --widen -- README COPYING INSTALL

and hack on a tree with Documentation/, README, COPYING, and INSTALL
present with no actual code to distract.  And "git checkout --no-widen"
could be a way to ask to respect the existing sparse pattern.

This patch isn't about tweaking the sparse-checkout pattern; instead,
it's about how "git checkout" interacts with the skip-worktree bit.
Maybe a good name would be --respect-skip-worktree?

[...]
> --- a/Documentation/git-checkout.txt
> +++ b/Documentation/git-checkout.txt
> @@ -180,6 +180,17 @@ branch by running "git rm -rf ." from the top level of the working tree.
>  Afterwards you will be ready to prepare your new files, repopulating the
>  working tree, by copying them from elsewhere, extracting a tarball, etc.
>  
> +--no-widen::
> +	In sparse checkout mode, `git checkout -- <paths>` would
> +	update all entries matched by <paths> regardless of sparse
> +	patterns. This option only updates entries matched by <paths>
> +	and sparse patterns.
> +
> +--widen::
> +	Revert the effect of `--no-widen` if specified and make
> +	`git checkout -- <paths>` update all entries matched by
> +	<paths> regardless of sparse patterns.

Perhaps, combining the descriptions of the positive and negative forms:

	--respect-skip-worktree::
		By default, `git checkout -- <paths>` creates or updates files
		matching <paths> regardless of the skip-worktree bit.  This
		option makes 'git checkout' skips entries with the
		skip-worktree bit set, which can be useful in sparse checkout
		mode.

I'm afraid I can't imagine when --no-respect-skip-worktree would be
useful.  That can easily be a failure of my imagination, though.

What do you think?

Thanks,
Jonathan