Re: [PATCH v2] odb: do not list our own refs as alternate refs in the quarantine

[Junio C Hamano <gitster@pobox.com>]

Junio C Hamano <gitster@pobox.com> writes:

> "Kristofer Karlsson via GitGitGadget" <gitgitgadget@gmail.com>
> writes:
>
>>     Changes since v1:
>>     ...
>>        quarantine outside of the commondir.
>
> All of the above changes make sense to me.
>
> This unfortunately crashes with Patrick's odb-reload-alternates
> series, but let me see if I can get a reasonable conflict resolution
> or if it is more reasonable to ask you to rebase this on the other
> topic.

I decided to queue it as-is instead of asking you to depend on the
other topic.  Here is what I got after making a trial merge to
'seen'.

I usually use "git show" to trigger the dense-combined diff format
(i.e., "git show --cc seen"), but "git show --remerge-diff seen"
output is shown below, just to see how easy it is to read.



commit b7f4d1e66b034c2a64b7f3323f9cd156a028f080
Merge: 1707829739 3f91b4bc4b
Author: Junio C Hamano <gitster@pobox.com>
Date:   Mon Nov 2 16:37:57 2026 -0800

    Merge branch 'kk/quarantine-alternate-refs' into seen
    
    The connectivity check in 'git-receive-pack(1)' has been optimized
    to not list the repository's own refs as alternate refs when running
    inside the object quarantine, avoiding redundant traversal of hidden
    refs.
    
    * kk/quarantine-alternate-refs:
      odb: do not list our own refs as alternate refs in the quarantine

diff --git a/Documentation/rev-list-options.adoc b/Documentation/rev-list-options.adoc
remerge CONFLICT (content): Merge conflict in Documentation/rev-list-options.adoc
index 4e92cf6456..d20c5f6372 100644
--- a/Documentation/rev-list-options.adoc
+++ b/Documentation/rev-list-options.adoc
@@ -223,23 +223,13 @@ explicitly.
 	Pretend as if all objects mentioned as ref tips of alternate
 	repositories were listed on the command line. An alternate
 	repository is any repository whose object directory is specified
-<<<<<<< 1707829739 (Merge branch 'kk/connectivity-check-ignore-replace' into seen)
 	in `objects/info/alternates`.  The refs of shallow and grafted
 	alternate repositories are ignored, as the history behind them
-	may be missing.  The set of included objects may be modified by
+	may be missing.  The repository's own object directory does not
+	count, even when it is passed in as an alternate, as happens
+	inside the object quarantine of	linkgit:git-receive-pack[1].
+	The set of included objects may be modified by
 	`core.alternateRefsCommand`, etc. See linkgit:git-config[1].
-||||||| ebdc087dc9
-	in `objects/info/alternates`.  The set of included objects may
-	be modified by `core.alternateRefsCommand`, etc. See
-	linkgit:git-config[1].
-=======
-	in `objects/info/alternates`.  The repository's own object
-	directory does not count, even when it is passed in as an
-	alternate, as happens inside the object quarantine of
-	linkgit:git-receive-pack[1].  The set of included objects may
-	be modified by `core.alternateRefsCommand`, etc. See
-	linkgit:git-config[1].
->>>>>>> 3f91b4bc4b (odb: do not list our own refs as alternate refs in the quarantine)
 
 `--single-worktree`::
 	By default, all working trees will be examined by the
diff --git a/odb/source-files.c b/odb/source-files.c
remerge CONFLICT (content): Merge conflict in odb/source-files.c
index 4239cb493c..8ce437fdc2 100644
--- a/odb/source-files.c
+++ b/odb/source-files.c
@@ -75,15 +75,9 @@ static void odb_source_files_free(struct odb_source *source)
 		odb_files_dir_free(files->dirs);
 		files->dirs = next;
 	}
-<<<<<<< 1707829739 (Merge branch 'kk/connectivity-check-ignore-replace' into seen)
 	strset_clear(&files->dir_paths);
 	stat_validity_clear(&files->alternates_validity);
-||||||| ebdc087dc9
-	hashmap_clear(&files->dirs_by_path);
-=======
-	hashmap_clear(&files->dirs_by_path);
 	free(files->quarantine_path);
->>>>>>> 3f91b4bc4b (odb: do not list our own refs as alternate refs in the quarantine)
 
 	odb_source_release(&files->base);
 	free(files);
@@ -362,15 +356,6 @@ static void read_alternates(const char *object_dir, struct strvec *out,
 	free(path);
 }
 
-<<<<<<< 1707829739 (Merge branch 'kk/connectivity-check-ignore-replace' into seen)
-static void add_alternate_recursively(struct odb_source_files *files,
-				      const char *path,
-				      int depth)
-||||||| ebdc087dc9
-static void odb_add_alternate_recursively(struct odb_source_files *files,
-					  const char *path,
-					  int depth)
-=======
 /*
  * Our own object directory is <commondir>/objects, or the parent of
  * GIT_QUARANTINE_PATH, as an object quarantine is created directly
@@ -410,10 +395,9 @@ static bool is_borrowed_object_dir(struct odb_source_files *files,
 	return ret;
 }
 
-static void odb_add_alternate_recursively(struct odb_source_files *files,
-					  const char *path,
-					  int depth)
->>>>>>> 3f91b4bc4b (odb: do not list our own refs as alternate refs in the quarantine)
+static void add_alternate_recursively(struct odb_source_files *files,
+				      const char *path,
+				      int depth)
 {
 	struct odb_files_dir *alternate;
 	struct strvec alternates = STRVEC_INIT;
diff --git a/odb/source-files.h b/odb/source-files.h
remerge CONFLICT (content): Merge conflict in odb/source-files.h
index 7afc2f28ad..9117dbea5b 100644
--- a/odb/source-files.h
+++ b/odb/source-files.h
@@ -70,22 +70,16 @@ struct odb_source_files {
 	 * Whether directory paths shall be compared case-insensitively, as
 	 * determined by "core.ignoreCase".
 	 */
-<<<<<<< 1707829739 (Merge branch 'kk/connectivity-check-ignore-replace' into seen)
 	int dir_paths_icase;
 
 	/* Stat data of the "info/alternates" file. */
 	struct stat_validity alternates_validity;
-||||||| ebdc087dc9
-	int dirs_paths_icase;
-=======
-	int dirs_paths_icase;
 
 	/*
 	 * The value of GIT_QUARANTINE_PATH when this source was set up from
 	 * the environment (see ODB_NEW_HONOR_ENV), or NULL.
 	 */
 	char *quarantine_path;
->>>>>>> 3f91b4bc4b (odb: do not list our own refs as alternate refs in the quarantine)
 };
 
 /* Allocate and initialize a new object source. */
diff --git a/t/t5618-alternate-refs.sh b/t/t5618-alternate-refs.sh
remerge CONFLICT (content): Merge conflict in t/t5618-alternate-refs.sh
index cefc37797c..048c7c63c1 100755
--- a/t/t5618-alternate-refs.sh
+++ b/t/t5618-alternate-refs.sh
@@ -58,34 +58,6 @@ test_expect_success 'log --source shows .alternate marker' '
 	test_cmp expect actual
 '
 
-<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< 1707829739 (Merge branch 'kk/connectivity-check-ignore-replace' into seen)
-test_expect_success 'connectivity check of a fetch excludes alternate refs' '
-	GIT_TRACE2_EVENT="$(pwd)/fetch.trace" git fetch origin &&
-	test_subcommand_flex git rev-list --objects --stdin --not --all \
-		--alternate-refs --quiet <fetch.trace
-'
-
-test_expect_success 'connectivity check of a deepening fetch excludes alternate refs' '
-	GIT_TRACE2_EVENT="$(pwd)/deepen.trace" git fetch --depth=1 origin one &&
-	test_subcommand_flex git rev-list --objects --stdin --not \
-		--alternate-refs --quiet <deepen.trace
-'
-
-test_expect_success 'refs of a shallow alternate are ignored' '
-	git clone --depth=1 --no-local . shallow &&
-	test_commit -C shallow shallow-only &&
-	shallow_tip=$(git -C shallow rev-parse HEAD) &&
-	cp .git/objects/info/alternates alternates.bak &&
-	test_when_finished "mv alternates.bak .git/objects/info/alternates" &&
-	echo "$(pwd)/shallow/.git/objects" >>.git/objects/info/alternates &&
-	git cat-file -e $shallow_tip &&
-	git rev-list --remotes=origin >expect &&
-	git rev-list --alternate-refs >actual &&
-	test_cmp expect actual
-'
-
-|||||||||||||||||||||||||||||||| ebdc087dc9
-================================
 # Our own object directory as an alternate is not a source of alternate
 # refs, but the alternates it brings in with it still are.
 test_expect_success 'own object directory as alternate lists only real alternates' '
@@ -120,5 +92,29 @@ test_expect_success 'parent of the quarantine is not listed as an alternate' '
 	test_must_be_empty actual
 '
 
->>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> 3f91b4bc4b (odb: do not list our own refs as alternate refs in the quarantine)
+test_expect_success 'connectivity check of a fetch excludes alternate refs' '
+	GIT_TRACE2_EVENT="$(pwd)/fetch.trace" git fetch origin &&
+	test_subcommand_flex git rev-list --objects --stdin --not --all \
+		--alternate-refs --quiet <fetch.trace
+'
+
+test_expect_success 'connectivity check of a deepening fetch excludes alternate refs' '
+	GIT_TRACE2_EVENT="$(pwd)/deepen.trace" git fetch --depth=1 origin one &&
+	test_subcommand_flex git rev-list --objects --stdin --not \
+		--alternate-refs --quiet <deepen.trace
+'
+
+test_expect_success 'refs of a shallow alternate are ignored' '
+	git clone --depth=1 --no-local . shallow &&
+	test_commit -C shallow shallow-only &&
+	shallow_tip=$(git -C shallow rev-parse HEAD) &&
+	cp .git/objects/info/alternates alternates.bak &&
+	test_when_finished "mv alternates.bak .git/objects/info/alternates" &&
+	echo "$(pwd)/shallow/.git/objects" >>.git/objects/info/alternates &&
+	git cat-file -e $shallow_tip &&
+	git rev-list --remotes=origin >expect &&
+	git rev-list --alternate-refs >actual &&
+	test_cmp expect actual
+'
+
 test_done