[BUG] 'git status --ignored' <pathspec> matches partial names

[BUG] 'git status --ignored' <pathspec> matches partial names

[Sean Whitton]

Steps to reproduce:

git init foo
cd foo
mkdir bar
echo bar/ >.gitignore
git init bar/baz
git init bar/quux
git status --porcelain --ignored --untracked-files -- ba

Expected output:
none, "ba" doesn't match "bar".

Actual output:
!! bar/baz/
!! bar/quux/

Credits to Lester Longley for the reproduction, in Emacs bug#81625.

-- 
Sean Whitton

Re: [BUG] 'git status --ignored' <pathspec> matches partial names

[René Scharfe]

On 9/14/26 3:31 PM, Sean Whitton wrote:
> Steps to reproduce:
> 
> git init foo
> cd foo
> mkdir bar
> echo bar/ >.gitignore
> git init bar/baz
> git init bar/quux
> git status --porcelain --ignored --untracked-files -- ba
> 
> Expected output:
> none, "ba" doesn't match "bar".
> 
> Actual output:
> !! bar/baz/
> !! bar/quux/
> 
> Credits to Lester Longley for the reproduction, in Emacs bug#81625.
> 

Bisects to 95c11ecc73 (Fix error-prone fill_directory() API; make it
only return matches, 2020-04-01).

I can reproduce the issue using the instructions above, but not in Git's
own repo like this:

   $ git status --porcelain --ignored --untracked-files -- .depend | grep -c '^!!'
   266
   $ git status --porcelain --ignored --untracked-files -- .depen | grep -c '^!!'
   0

Below is a quick fix, but perhaps this optimization can be repaired
instead of removed.

René


diff --git a/dir.c b/dir.c
index 95d8a1cce9..3718301a89 100644
--- a/dir.c
+++ b/dir.c
@@ -1991,11 +1991,9 @@ static enum path_treatment treat_directory(struct dir_struct *dir,
 	/*
 	 * We don't want to descend into paths that don't match the necessary
 	 * patterns.  Clearly, if we don't have a pathspec, then we can't check
-	 * for matching patterns.  Also, if (excluded) then we know we matched
-	 * the exclusion patterns so as an optimization we can skip checking
 	 * for matching patterns.
 	 */
-	if (pathspec && !excluded) {
+	if (pathspec) {
 		matches_how = match_pathspec_with_flags(istate, pathspec,
 							dirname, len,
 							0 /* prefix */,

[PATCH] dir: skip excluded directory with nested repo on prefix match

[René Scharfe]

95c11ecc73 (Fix error-prone fill_directory() API; make it only return
matches, 2020-04-01) optimized away pathspec matching too eagerly and
cada7308ad (dir: check pathspecs before returning `path_excluded`,
2020-07-20) fixed that for files and symlinks.

A corner case remained unaddressed: Ignored directories that contain a
nested repository.  Make sure to run match_pathspec_with_flags() for it
if necessary.

Reported-by: Sean Whitton <spwhitton@spwhitton.name>
Reported-by: Lester Longley <lester@ieee.org>
Signed-off-by: René Scharfe <l.s.r@web.de>
---
 dir.c                      | 25 ++++++++++++++++++-------
 t/t7061-wtstatus-ignore.sh |  5 +++++
 2 files changed, 23 insertions(+), 7 deletions(-)

diff --git a/dir.c b/dir.c
index 95d8a1cce9..0557a59d5e 100644
--- a/dir.c
+++ b/dir.c
@@ -1930,6 +1930,16 @@ static enum exist_status directory_exists_in_index(struct index_state *istate,
 	return index_nonexistent;
 }
 
+static int dir_match(struct index_state *istate,
+		     const struct pathspec *pathspec,
+		     const char *dirname, int len)
+{
+	return match_pathspec_with_flags(istate, pathspec, dirname, len,
+					 0 /* prefix */,
+					 NULL /* seen */,
+					 DO_MATCH_LEADING_PATHSPEC);
+}
+
 /*
  * When we find a directory when traversing the filesystem, we
  * have three distinct cases:
@@ -1996,11 +2006,7 @@ static enum path_treatment treat_directory(struct dir_struct *dir,
 	 * for matching patterns.
 	 */
 	if (pathspec && !excluded) {
-		matches_how = match_pathspec_with_flags(istate, pathspec,
-							dirname, len,
-							0 /* prefix */,
-							NULL /* seen */,
-							DO_MATCH_LEADING_PATHSPEC);
+		matches_how = dir_match(istate, pathspec, dirname, len);
 		if (!matches_how)
 			return path_none;
 	}
@@ -2034,8 +2040,13 @@ static enum path_treatment treat_directory(struct dir_struct *dir,
 		strbuf_release(&sb);
 
 		if (nested_repo) {
-			if ((dir->flags & DIR_SKIP_NESTED_GIT) ||
-				(matches_how == MATCHED_RECURSIVELY_LEADING_PATHSPEC))
+			if (dir->flags & DIR_SKIP_NESTED_GIT)
+				return path_none;
+			if (!matches_how)
+				matches_how = dir_match(istate, pathspec,
+							dirname, len);
+			if (!matches_how ||
+			    matches_how == MATCHED_RECURSIVELY_LEADING_PATHSPEC)
 				return path_none;
 			return excluded ? path_excluded : path_untracked;
 		}
diff --git a/t/t7061-wtstatus-ignore.sh b/t/t7061-wtstatus-ignore.sh
index 14ddaba2f3..182933471f 100755
--- a/t/t7061-wtstatus-ignore.sh
+++ b/t/t7061-wtstatus-ignore.sh
@@ -340,4 +340,9 @@ test_expect_success 'status ignores submodule in excluded directory' '
 	test_cmp expected actual
 '
 
+test_expect_success 'status omits excluded directory with submodule on prefix match' '
+	git status --porcelain --ignored -u tracke >actual &&
+	test_must_be_empty actual
+'
+
 test_done
-- 
2.55.0

Re: [PATCH] dir: skip excluded directory with nested repo on prefix match

[Junio C Hamano]

René Scharfe <l.s.r@web.de> writes:

> +static int dir_match(struct index_state *istate,
> +		     const struct pathspec *pathspec,
> +		     const char *dirname, int len)
> +{
> +	return match_pathspec_with_flags(istate, pathspec, dirname, len,
> +					 0 /* prefix */,
> +					 NULL /* seen */,
> +					 DO_MATCH_LEADING_PATHSPEC);
> +}

OK, this is a good helper to extract and reuse.

> @@ -1996,11 +2006,7 @@ static enum path_treatment treat_directory(struct dir_struct *dir,
>  	 * for matching patterns.
>  	 */
>  	if (pathspec && !excluded) {
> -		matches_how = match_pathspec_with_flags(istate, pathspec,
> -							dirname, len,
> -							0 /* prefix */,
> -							NULL /* seen */,
> -							DO_MATCH_LEADING_PATHSPEC);
> +		matches_how = dir_match(istate, pathspec, dirname, len);
>  		if (!matches_how)
>  			return path_none;
>  	}

So, this hunk shows that the treat_directory() function is prepared
to be passed a NULL in pathspec.  We make sure we do not trigger
match_pathspec_with_flags() when pathspec is NULL, and this should
extends to dir_match() now.  This is a very sensible conditional, as
match_pathspec_with_flags() calls do_match_pathspec() as the first
thing, which begins with GUARD_PATHSPEC() macro that unconditionally
dereferences the pathspec.

> @@ -2034,8 +2040,13 @@ static enum path_treatment treat_directory(struct dir_struct *dir,
>  		strbuf_release(&sb);
>  
>  		if (nested_repo) {
> -			if ((dir->flags & DIR_SKIP_NESTED_GIT) ||
> -				(matches_how == MATCHED_RECURSIVELY_LEADING_PATHSPEC))
> +			if (dir->flags & DIR_SKIP_NESTED_GIT)
> +				return path_none;
> +			if (!matches_how)
> +				matches_how = dir_match(istate, pathspec,
> +							dirname, len);
> +			if (!matches_how ||
> +			    matches_how == MATCHED_RECURSIVELY_LEADING_PATHSPEC)
>  				return path_none;

Here, we do not know if we have pathspec==NULL.  Shouldn't "make
sure we have a result from dir_match() and return path_none as
appropriate" be done only when pathspec != NULL or something like
that, since dir_match() will crash if pathspec is NULL?

Taking all together, something along the following line squashed
into your patch, perhaps?  The newly added test is not essential; it
merely is to demonstrate why an extra conditional I added below
would help avoid segfaulting.

 dir.c                      | 15 +++++++++------
 t/t7061-wtstatus-ignore.sh | 25 +++++++++++++++++++++++++
 2 files changed, 34 insertions(+), 6 deletions(-)

diff --git c/dir.c w/dir.c
index 6bda650891..8e858c26d1 100644
--- c/dir.c
+++ w/dir.c
@@ -2042,12 +2042,15 @@ static enum path_treatment treat_directory(struct dir_struct *dir,
 		if (nested_repo) {
 			if (dir->flags & DIR_SKIP_NESTED_GIT)
 				return path_none;
-			if (!matches_how)
-				matches_how = dir_match(istate, pathspec,
-							dirname, len);
-			if (!matches_how ||
-			    matches_how == MATCHED_RECURSIVELY_LEADING_PATHSPEC)
-				return path_none;
+
+			if (pathspec) {
+				if (!matches_how)
+					matches_how = dir_match(istate, pathspec,
+								dirname, len);
+				if (!matches_how ||
+				    matches_how == MATCHED_RECURSIVELY_LEADING_PATHSPEC)
+					return path_none;
+			}
 			return excluded ? path_excluded : path_untracked;
 		}
 	}
diff --git c/t/t7061-wtstatus-ignore.sh w/t/t7061-wtstatus-ignore.sh
index 182933471f..6bc680312e 100755
--- c/t/t7061-wtstatus-ignore.sh
+++ w/t/t7061-wtstatus-ignore.sh
@@ -340,6 +340,31 @@ test_expect_success 'status ignores submodule in excluded directory' '
 	test_cmp expected actual
 '
 
+test_expect_success 'replace directory with untracked nested repo' '
+	test_create_repo checkout-nested &&
+	(
+		cd checkout-nested &&
+		test_commit base &&
+
+		# Branch with tracked file "dir"
+		git checkout -b branch-file &&
+		echo "tracked file" >dir &&
+		git add dir &&
+		git commit -m "add file dir" &&
+
+		# Switch back to base
+		git checkout -b branch-nested base &&
+
+		# Create an untracked directory containing a nested git repo
+		mkdir -p dir/nested &&
+		git init dir/nested &&
+
+		# Attempting checkout invokes verify_clean_subdirectory()
+		# with pathspec=NULL
+		test_must_fail git checkout branch-file
+	)
+'
+
 test_expect_success 'status omits excluded directory with submodule on prefix match' '
 	git status --porcelain --ignored -u tracke >actual &&
 	test_must_be_empty actual

[PATCH v2] dir: skip excluded directory with nested repo on prefix match

[René Scharfe]

95c11ecc73 (Fix error-prone fill_directory() API; make it only return
matches, 2020-04-01) optimized away pathspec matching too eagerly and
cada7308ad (dir: check pathspecs before returning `path_excluded`,
2020-07-20) fixed that for files and symlinks.

A corner case remained unaddressed: Ignored directories that contain a
nested repository.  Make sure to run match_pathspec_with_flags() for it
if necessary.

Add a status test to check whether the pathspec is applied correctly as
well as a checkout test to exercise the changed code without a pathspec.

Reported-by: Sean Whitton <spwhitton@spwhitton.name>
Reported-by: Lester Longley <lester@ieee.org>
Helped-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: René Scharfe <l.s.r@web.de>
---
 dir.c                         | 27 ++++++++++++++++++++-------
 t/t2021-checkout-overwrite.sh |  7 +++++++
 t/t7061-wtstatus-ignore.sh    |  5 +++++
 3 files changed, 32 insertions(+), 7 deletions(-)

diff --git a/dir.c b/dir.c
index d896e7be4b..ac246ced1d 100644
--- a/dir.c
+++ b/dir.c
@@ -1935,6 +1935,16 @@ static enum exist_status directory_exists_in_index(struct index_state *istate,
 	return index_nonexistent;
 }
 
+static int dir_match(struct index_state *istate,
+		     const struct pathspec *pathspec,
+		     const char *dirname, int len)
+{
+	return match_pathspec_with_flags(istate, pathspec, dirname, len,
+					 0 /* prefix */,
+					 NULL /* seen */,
+					 DO_MATCH_LEADING_PATHSPEC);
+}
+
 /*
  * When we find a directory when traversing the filesystem, we
  * have three distinct cases:
@@ -2001,11 +2011,7 @@ static enum path_treatment treat_directory(struct dir_struct *dir,
 	 * for matching patterns.
 	 */
 	if (pathspec && !excluded) {
-		matches_how = match_pathspec_with_flags(istate, pathspec,
-							dirname, len,
-							0 /* prefix */,
-							NULL /* seen */,
-							DO_MATCH_LEADING_PATHSPEC);
+		matches_how = dir_match(istate, pathspec, dirname, len);
 		if (!matches_how)
 			return path_none;
 	}
@@ -2039,8 +2045,15 @@ static enum path_treatment treat_directory(struct dir_struct *dir,
 		strbuf_release(&sb);
 
 		if (nested_repo) {
-			if ((dir->flags & DIR_SKIP_NESTED_GIT) ||
-				(matches_how == MATCHED_RECURSIVELY_LEADING_PATHSPEC))
+			if (dir->flags & DIR_SKIP_NESTED_GIT)
+				return path_none;
+			if (pathspec && !matches_how) {
+				matches_how = dir_match(istate, pathspec,
+							dirname, len);
+				if (!matches_how)
+					return path_none;
+			}
+			if (matches_how == MATCHED_RECURSIVELY_LEADING_PATHSPEC)
 				return path_none;
 			return excluded ? path_excluded : path_untracked;
 		}
diff --git a/t/t2021-checkout-overwrite.sh b/t/t2021-checkout-overwrite.sh
index 38c41ae373..2b7fff5159 100755
--- a/t/t2021-checkout-overwrite.sh
+++ b/t/t2021-checkout-overwrite.sh
@@ -79,4 +79,11 @@ test_expect_success 'checkout --overwrite-ignore should succeed if only ignored
 	test_path_is_file some_dir
 '
 
+test_expect_success 'checkout must not overwrite untracked nested repo' '
+	git checkout -f start &&
+	rm -rf some_dir &&
+	git init some_dir &&
+	test_must_fail git checkout df_conflict
+'
+
 test_done
diff --git a/t/t7061-wtstatus-ignore.sh b/t/t7061-wtstatus-ignore.sh
index 14ddaba2f3..182933471f 100755
--- a/t/t7061-wtstatus-ignore.sh
+++ b/t/t7061-wtstatus-ignore.sh
@@ -340,4 +340,9 @@ test_expect_success 'status ignores submodule in excluded directory' '
 	test_cmp expected actual
 '
 
+test_expect_success 'status omits excluded directory with submodule on prefix match' '
+	git status --porcelain --ignored -u tracke >actual &&
+	test_must_be_empty actual
+'
+
 test_done

Interdiff against v1:
  diff --git a/dir.c b/dir.c
  index aa457f0f4e..ac246ced1d 100644
  --- a/dir.c
  +++ b/dir.c
  @@ -2047,11 +2047,13 @@ static enum path_treatment treat_directory(struct dir_struct *dir,
   		if (nested_repo) {
   			if (dir->flags & DIR_SKIP_NESTED_GIT)
   				return path_none;
  -			if (!matches_how)
  +			if (pathspec && !matches_how) {
   				matches_how = dir_match(istate, pathspec,
   							dirname, len);
  -			if (!matches_how ||
  -			    matches_how == MATCHED_RECURSIVELY_LEADING_PATHSPEC)
  +				if (!matches_how)
  +					return path_none;
  +			}
  +			if (matches_how == MATCHED_RECURSIVELY_LEADING_PATHSPEC)
   				return path_none;
   			return excluded ? path_excluded : path_untracked;
   		}
  diff --git a/t/t2021-checkout-overwrite.sh b/t/t2021-checkout-overwrite.sh
  index 38c41ae373..2b7fff5159 100755
  --- a/t/t2021-checkout-overwrite.sh
  +++ b/t/t2021-checkout-overwrite.sh
  @@ -79,4 +79,11 @@ test_expect_success 'checkout --overwrite-ignore should succeed if only ignored
   	test_path_is_file some_dir
   '
   
  +test_expect_success 'checkout must not overwrite untracked nested repo' '
  +	git checkout -f start &&
  +	rm -rf some_dir &&
  +	git init some_dir &&
  +	test_must_fail git checkout df_conflict
  +'
  +
   test_done
-- 
2.55.0

Re: [PATCH] dir: skip excluded directory with nested repo on prefix match

[René Scharfe]

On 9/22/26 6:57 AM, Junio C Hamano wrote:
> René Scharfe <l.s.r@web.de> writes:
> 
>> @@ -2034,8 +2040,13 @@ static enum path_treatment treat_directory(struct dir_struct *dir,
>>  		strbuf_release(&sb);
>>  
>>  		if (nested_repo) {
>> -			if ((dir->flags & DIR_SKIP_NESTED_GIT) ||
>> -				(matches_how == MATCHED_RECURSIVELY_LEADING_PATHSPEC))
>> +			if (dir->flags & DIR_SKIP_NESTED_GIT)
>> +				return path_none;
>> +			if (!matches_how)
>> +				matches_how = dir_match(istate, pathspec,
>> +							dirname, len);
>> +			if (!matches_how ||
>> +			    matches_how == MATCHED_RECURSIVELY_LEADING_PATHSPEC)
>>  				return path_none;
> 
> Here, we do not know if we have pathspec==NULL.  Shouldn't "make
> sure we have a result from dir_match() and return path_none as
> appropriate" be done only when pathspec != NULL or something like
> that, since dir_match() will crash if pathspec is NULL?

Ugh, nasty, that was silly of me.  Thanks for finding this bug!

René