Re: [PATCH] sha1-name.c: for ":/", find detached HEAD commits

[Duy Nguyen <pclouds@gmail.com>]

On Tue, Jul 10, 2018 at 5:44 PM William Chargin <wchargin@gmail.com> wrote:
>
> This patch broadens the set of commits matched by ":/" pathspecs to
> include commits reachable from HEAD but not any named ref. This avoids
> surprising behavior when working with a detached HEAD and trying to
> refer to a commit that was recently created and only exists within the
> detached state.

Cool!

>
> Signed-off-by: William Chargin <wchargin@gmail.com>
> Based-on-patch-by: Jeff King <peff@peff.net>
> ---
>  Documentation/revisions.txt   | 10 +++++-----
>  sha1-name.c                   |  1 +
>  t/t4208-log-magic-pathspec.sh | 14 ++++++++++++++
>  3 files changed, 20 insertions(+), 5 deletions(-)
>
> diff --git a/Documentation/revisions.txt b/Documentation/revisions.txt
> index 7d1bd4409..aa56907fd 100644
> --- a/Documentation/revisions.txt
> +++ b/Documentation/revisions.txt
> @@ -181,11 +181,11 @@ existing tag object.
>    the '<rev>' before '{caret}'.
>
>  ':/<text>', e.g. ':/fix nasty bug'::
> -  A colon, followed by a slash, followed by a text, names
> -  a commit whose commit message matches the specified regular expression.
> -  This name returns the youngest matching commit which is
> -  reachable from any ref. The regular expression can match any part of the
> -  commit message. To match messages starting with a string, one can use
> +  A colon, followed by a slash, followed by a text, names a commit whose
> +  commit message matches the specified regular expression. This name
> +  returns the youngest matching commit which is reachable from any ref
> +  or from HEAD. The regular expression can match any part of the commit
> +  message. To match messages starting with a string, one can use
>    e.g. ':/^foo'. The special sequence ':/!' is reserved for modifiers to what
>    is matched. ':/!-foo' performs a negative match, while ':/!!foo' matches a
>    literal '!' character, followed by 'foo'. Any other sequence beginning with
> diff --git a/sha1-name.c b/sha1-name.c
> index 60d9ef3c7..641ca12f9 100644
> --- a/sha1-name.c
> +++ b/sha1-name.c
> @@ -1650,6 +1650,7 @@ static int get_oid_with_context_1(const char *name,
>                         struct commit_list *list = NULL;
>
>                         for_each_ref(handle_one_ref, &list);
> +                       head_ref(handle_one_ref, &list);

When multiple worktrees are used, should we consider all HEADs or just
current worktree's HEAD?

This is the latter case, if we should go with the former (I don't
know, it's a genuine question) then you need one more call:
other_head_refs().

>                         commit_list_sort_by_date(&list);
>                         return get_oid_oneline(name + 2, oid, list);
>                 }
> diff --git a/t/t4208-log-magic-pathspec.sh b/t/t4208-log-magic-pathspec.sh
> index 62f335b2d..41b9f3eba 100755
> --- a/t/t4208-log-magic-pathspec.sh
> +++ b/t/t4208-log-magic-pathspec.sh
> @@ -25,6 +25,20 @@ test_expect_success '"git log :/a -- " should not be ambiguous' '
>         git log :/a --
>  '
>
> +test_expect_success '"git log :/detached -- " should find a commit only in HEAD' '
> +       test_when_finished "git checkout master" &&
> +       git checkout --detach &&
> +       test_tick &&
> +       git commit --allow-empty -m detached &&
> +       test_tick &&
> +       git commit --allow-empty -m something-else &&
> +       git log :/detached --
> +'
> +
> +test_expect_success '"git log :/detached -- " should not find an orphaned commit' '
> +       test_must_fail git log :/detached --
> +'
> +
>  test_expect_success '"git log -- :/a" should not be ambiguous' '
>         git log -- :/a
>  '
> --
> 2.18.0.130.g61d0c9dcf
>


-- 
Duy