[PATCH] apply: strip ./ prefix from --directory argument

[PATCH] apply: strip ./ prefix from --directory argument

[Joaquim Rocha via GitGitGadget]

From: Joaquim Rocha <joaquim@amutable.com>

When passing a relative path like --directory=./some/sub, the leading
"./" caused apply to prepend it literally to patch filenames, resulting
in an error (invalid path).

Since using "./" is almost memory muscle for many, strip the "./"
prefix so it behaves the same as --directory=some/sub.

Signed-off-by: Joaquim Rocha <joaquim@amutable.com>
---
    apply: strip ./ prefix from --directory argument

Published-As: https://github.com/gitgitgadget/git/releases/tag/pr-git-2198%2Fjoaquimrocha%2Fapply-directory-dot-slash-prefix-v1
Fetch-It-Via: git fetch https://github.com/gitgitgadget/git pr-git-2198/joaquimrocha/apply-directory-dot-slash-prefix-v1
Pull-Request: https://github.com/git/git/pull/2198

 apply.c               | 4 ++++
 t/t4128-apply-root.sh | 9 +++++++++
 2 files changed, 13 insertions(+)

diff --git a/apply.c b/apply.c
index 3de4aa4d2e..a44c54077c 100644
--- a/apply.c
+++ b/apply.c
@@ -5001,6 +5001,10 @@ static int apply_option_parse_directory(const struct option *opt,
 	BUG_ON_OPT_NEG(unset);
 
 	strbuf_reset(&state->root);
+
+	if (starts_with(arg, "./"))
+		arg += 2;
+
 	strbuf_addstr(&state->root, arg);
 	strbuf_complete(&state->root, '/');
 	return 0;
diff --git a/t/t4128-apply-root.sh b/t/t4128-apply-root.sh
index f6db5a79dd..2f446a4d69 100755
--- a/t/t4128-apply-root.sh
+++ b/t/t4128-apply-root.sh
@@ -43,6 +43,15 @@ test_expect_success 'apply --directory -p (2) ' '
 
 '
 
+test_expect_success 'apply --directory (./ prefix)' '
+	git reset --hard initial &&
+	git apply --directory=./some/sub -p3 --index patch &&
+	echo Bello >expect &&
+	git show :some/sub/dir/file >actual &&
+	test_cmp expect actual &&
+	test_cmp expect some/sub/dir/file
+'
+
 cat > patch << EOF
 diff --git a/newfile b/newfile
 new file mode 100644

base-commit: 6fcee4785280a08e7f271bd015a4dc33753e2886
-- 
gitgitgadget

Re: [PATCH] apply: strip ./ prefix from --directory argument

[Patrick Steinhardt]

On Fri, Feb 13, 2026 at 05:08:30PM +0000, Joaquim Rocha via GitGitGadget wrote:
> From: Joaquim Rocha <joaquim@amutable.com>
> 
> When passing a relative path like --directory=./some/sub, the leading
> "./" caused apply to prepend it literally to patch filenames, resulting
> in an error (invalid path).
> 
> Since using "./" is almost memory muscle for many, strip the "./"
> prefix so it behaves the same as --directory=some/sub.

Isn't the problem wider than that though? For example, if you had
"././some/sub" it would break again. Or if you had "some/./sub", or
"some/sub/../sub", or "some//sub".

> diff --git a/apply.c b/apply.c
> index 3de4aa4d2e..a44c54077c 100644
> --- a/apply.c
> +++ b/apply.c
> @@ -5001,6 +5001,10 @@ static int apply_option_parse_directory(const struct option *opt,
>  	BUG_ON_OPT_NEG(unset);
>  
>  	strbuf_reset(&state->root);
> +
> +	if (starts_with(arg, "./"))
> +		arg += 2;
> +
>  	strbuf_addstr(&state->root, arg);
>  	strbuf_complete(&state->root, '/');
>  	return 0;

While this change here fixes your observed issues, the next person might
run into a totally different one. So more generally, I think what we'd
rather want to do is to fully normalize the path. How about this
instead:

diff --git a/apply.c b/apply.c
index 9de2eb953e..8946b133a3 100644
--- a/apply.c
+++ b/apply.c
@@ -5002,6 +5002,7 @@ static int apply_option_parse_directory(const struct option *opt,
 
 	strbuf_reset(&state->root);
 	strbuf_addstr(&state->root, arg);
+	strbuf_normalize_path(&state->root);
 	strbuf_complete(&state->root, '/');
 	return 0;
 }

`strbuf_normalize_path()` drops "." components, removes ".." and it
squashes multiple directory separators. So it handles your specific use
case, but also others.

Thanks!

Patrick

Re: [PATCH] apply: strip ./ prefix from --directory argument

[Junio C Hamano]

Patrick Steinhardt <ps@pks.im> writes:

> While this change here fixes your observed issues, the next person might
> run into a totally different one. So more generally, I think what we'd
> rather want to do is to fully normalize the path. How about this
> instead:

Sorry, but I am confused.  Why isn't "don't do it then" a good
answer for a case like this?

>
> diff --git a/apply.c b/apply.c
> index 9de2eb953e..8946b133a3 100644
> --- a/apply.c
> +++ b/apply.c
> @@ -5002,6 +5002,7 @@ static int apply_option_parse_directory(const struct option *opt,
>  
>  	strbuf_reset(&state->root);
>  	strbuf_addstr(&state->root, arg);
> +	strbuf_normalize_path(&state->root);
>  	strbuf_complete(&state->root, '/');
>  	return 0;
>  }
>
> `strbuf_normalize_path()` drops "." components, removes ".." and it
> squashes multiple directory separators. So it handles your specific use
> case, but also others.
>
> Thanks!
>
> Patrick

[PATCH v2] apply: normalize path in --directory argument

[Joaquim Rocha via GitGitGadget]

From: Joaquim Rocha <joaquim@amutable.com>

When passing a relative path like --directory=./some/sub, the leading
"./" caused apply to prepend it literally to patch filenames, resulting
in an error (invalid path).
There may be more cases like this where users pass some/./path to the
directory which can easily be normalized to an acceptable path, so
these changes try to normalize the path before using it.

Signed-off-by: Joaquim Rocha <joaquim@amutable.com>
---
    apply: strip ./ prefix from --directory argument
    
    Changes since v1:
    
     * Normalized the path as Patrick recommended
     * Return error is we have ../ at the beginning of the --directory
       argument

Published-As: https://github.com/gitgitgadget/git/releases/tag/pr-git-2198%2Fjoaquimrocha%2Fapply-directory-dot-slash-prefix-v2
Fetch-It-Via: git fetch https://github.com/gitgitgadget/git pr-git-2198/joaquimrocha/apply-directory-dot-slash-prefix-v2
Pull-Request: https://github.com/git/git/pull/2198

Range-diff vs v1:

 1:  82e24c3471 ! 1:  8ac66a876d apply: strip ./ prefix from --directory argument
     @@ Metadata
      Author: Joaquim Rocha <joaquim@amutable.com>
      
       ## Commit message ##
     -    apply: strip ./ prefix from --directory argument
     +    apply: normalize path in --directory argument
      
          When passing a relative path like --directory=./some/sub, the leading
          "./" caused apply to prepend it literally to patch filenames, resulting
          in an error (invalid path).
     -
     -    Since using "./" is almost memory muscle for many, strip the "./"
     -    prefix so it behaves the same as --directory=some/sub.
     +    There may be more cases like this where users pass some/./path to the
     +    directory which can easily be normalized to an acceptable path, so
     +    these changes try to normalize the path before using it.
      
          Signed-off-by: Joaquim Rocha <joaquim@amutable.com>
      
       ## apply.c ##
      @@ apply.c: static int apply_option_parse_directory(const struct option *opt,
     - 	BUG_ON_OPT_NEG(unset);
       
       	strbuf_reset(&state->root);
     + 	strbuf_addstr(&state->root, arg);
      +
     -+	if (starts_with(arg, "./"))
     -+		arg += 2;
     ++	if (strbuf_normalize_path(&state->root) < 0)
     ++		return error(_("unable to normalize directory: '%s'"), arg);
      +
     - 	strbuf_addstr(&state->root, arg);
       	strbuf_complete(&state->root, '/');
       	return 0;
     + }
      
       ## t/t4128-apply-root.sh ##
      @@ t/t4128-apply-root.sh: test_expect_success 'apply --directory -p (2) ' '
     @@ t/t4128-apply-root.sh: test_expect_success 'apply --directory -p (2) ' '
      +	test_cmp expect actual &&
      +	test_cmp expect some/sub/dir/file
      +'
     ++
     ++test_expect_success 'apply --directory (double slash)' '
     ++	git reset --hard initial &&
     ++	git apply --directory=some//sub -p3 --index patch &&
     ++	echo Bello >expect &&
     ++	git show :some/sub/dir/file >actual &&
     ++	test_cmp expect actual &&
     ++	test_cmp expect some/sub/dir/file
     ++'
     ++
     ++test_expect_success 'apply --directory (./ in the middle)' '
     ++	git reset --hard initial &&
     ++	git apply --directory=some/./sub -p3 --index patch &&
     ++	echo Bello >expect &&
     ++	git show :some/sub/dir/file >actual &&
     ++	test_cmp expect actual &&
     ++	test_cmp expect some/sub/dir/file
     ++'
     ++
     ++test_expect_success 'apply --directory (../ in the middle)' '
     ++	git reset --hard initial &&
     ++	git apply --directory=some/../some/sub -p3 --index patch &&
     ++	echo Bello >expect &&
     ++	git show :some/sub/dir/file >actual &&
     ++	test_cmp expect actual &&
     ++	test_cmp expect some/sub/dir/file
     ++'
     ++
     ++test_expect_success 'apply --directory rejects leading ../' '
     ++	test_must_fail git apply --directory=../foo -p3 patch 2>err &&
     ++	test_grep "unable to normalize directory" err
     ++'
      +
       cat > patch << EOF
       diff --git a/newfile b/newfile


 apply.c               |  4 ++++
 t/t4128-apply-root.sh | 41 +++++++++++++++++++++++++++++++++++++++++
 2 files changed, 45 insertions(+)

diff --git a/apply.c b/apply.c
index 3de4aa4d2e..7f0ce5918b 100644
--- a/apply.c
+++ b/apply.c
@@ -5002,6 +5002,10 @@ static int apply_option_parse_directory(const struct option *opt,
 
 	strbuf_reset(&state->root);
 	strbuf_addstr(&state->root, arg);
+
+	if (strbuf_normalize_path(&state->root) < 0)
+		return error(_("unable to normalize directory: '%s'"), arg);
+
 	strbuf_complete(&state->root, '/');
 	return 0;
 }
diff --git a/t/t4128-apply-root.sh b/t/t4128-apply-root.sh
index f6db5a79dd..5eba15fa66 100755
--- a/t/t4128-apply-root.sh
+++ b/t/t4128-apply-root.sh
@@ -43,6 +43,47 @@ test_expect_success 'apply --directory -p (2) ' '
 
 '
 
+test_expect_success 'apply --directory (./ prefix)' '
+	git reset --hard initial &&
+	git apply --directory=./some/sub -p3 --index patch &&
+	echo Bello >expect &&
+	git show :some/sub/dir/file >actual &&
+	test_cmp expect actual &&
+	test_cmp expect some/sub/dir/file
+'
+
+test_expect_success 'apply --directory (double slash)' '
+	git reset --hard initial &&
+	git apply --directory=some//sub -p3 --index patch &&
+	echo Bello >expect &&
+	git show :some/sub/dir/file >actual &&
+	test_cmp expect actual &&
+	test_cmp expect some/sub/dir/file
+'
+
+test_expect_success 'apply --directory (./ in the middle)' '
+	git reset --hard initial &&
+	git apply --directory=some/./sub -p3 --index patch &&
+	echo Bello >expect &&
+	git show :some/sub/dir/file >actual &&
+	test_cmp expect actual &&
+	test_cmp expect some/sub/dir/file
+'
+
+test_expect_success 'apply --directory (../ in the middle)' '
+	git reset --hard initial &&
+	git apply --directory=some/../some/sub -p3 --index patch &&
+	echo Bello >expect &&
+	git show :some/sub/dir/file >actual &&
+	test_cmp expect actual &&
+	test_cmp expect some/sub/dir/file
+'
+
+test_expect_success 'apply --directory rejects leading ../' '
+	test_must_fail git apply --directory=../foo -p3 patch 2>err &&
+	test_grep "unable to normalize directory" err
+'
+
 cat > patch << EOF
 diff --git a/newfile b/newfile
 new file mode 100644

base-commit: 6fcee4785280a08e7f271bd015a4dc33753e2886
-- 
gitgitgadget

Re: [PATCH] apply: strip ./ prefix from --directory argument

[Patrick Steinhardt]

On Tue, Feb 17, 2026 at 12:27:39PM -0800, Junio C Hamano wrote:
> Patrick Steinhardt <ps@pks.im> writes:
> 
> > While this change here fixes your observed issues, the next person might
> > run into a totally different one. So more generally, I think what we'd
> > rather want to do is to fully normalize the path. How about this
> > instead:
> 
> Sorry, but I am confused.  Why isn't "don't do it then" a good
> answer for a case like this?

I guess that's fair, but especially with command line completion it
might be easy to arrive at such paths. That may or may not be a good
argument, I'm not sure myself.

Patrick

Re: [PATCH] apply: strip ./ prefix from --directory argument

[Joaquim Rocha]

On Wed, Feb 18, 2026 at 2:14 PM Patrick Steinhardt <ps@pks.im> wrote:
>
> I guess that's fair, but especially with command line completion it
> might be easy to arrive at such paths. That may or may not be a good
> argument, I'm not sure myself.
>
> Patrick

I understand that. TBH, while not at your (plural) level of expertise
in git, I am certainly an experienced user and still the error from
the ./ use got me confused. So my proposal goes towards developer
experience, like the similar command suggestions it also has. If
there's no down side to it, I think it makes sense to have it.

An alternative would be to have a better error message if we detect
there are redundant path artifacts, but in that case why wouldn't we
just normalize the path as it's the user's clear intention?

Cheers,

Joaquim Rocha

Re: [PATCH v2] apply: normalize path in --directory argument

[Junio C Hamano]

"Joaquim Rocha via GitGitGadget" <gitgitgadget@gmail.com> writes:

> From: Joaquim Rocha <joaquim@amutable.com>
>
> When passing a relative path like --directory=./some/sub, the leading
> "./" caused apply to prepend it literally to patch filenames, resulting
> in an error (invalid path).
> There may be more cases like this where users pass some/./path to the
> directory which can easily be normalized to an acceptable path, so
> these changes try to normalize the path before using it.
>
> Signed-off-by: Joaquim Rocha <joaquim@amutable.com>
> ---
>     apply: strip ./ prefix from --directory argument
>     
>     Changes since v1:
>     
>      * Normalized the path as Patrick recommended

Sounds like a sensible direction to go.

Will queue.  Thanks.  (of course, further reviews welcome).