[pull] master from git:master

Documentation/RelNotes/2.51.0.adoc

@@ -103,6 +103,10 @@ Performance, Internal Implementation, Development Support etc.
  * GIT_TEST_INSTALLED was not honored in the recent topic related to
    SHA256 hashes, which has been corrected.
 
+ * The pop_most_recent_commit() function can have quite expensive
+   worst case performance characteristics, which has been optimized by
+   using prio-queue data structure.
+
 
 Fixes since v2.50
 -----------------
@@ -225,6 +229,11 @@ including security updates, are included in this release.
    patches off.
    (merge 1f0fed312a bc/contribution-under-non-real-names later to maint).
 
+ * "git commit" that concludes a conflicted merge failed to notice and remove
+   existing comment added automatically (like "# Conflicts:") when the
+   core.commentstring is set to 'auto'.
+   (merge 92b7c7c9f5 ac/auto-comment-char-fix later to maint).
+
  * Other code cleanup, docfix, build fix, etc.
    (merge b257adb571 lo/my-first-ow-doc-update later to maint).
    (merge 8b34b6a220 ly/sequencer-update-squash-is-fixup-only later to maint).

builtin/commit.c

@@ -688,6 +688,10 @@ static void adjust_comment_line_char(const struct strbuf *sb)
 	char candidates[] = "#;@!$%^&|:";
 	char *candidate;
 	const char *p;
+	size_t cutoff;
+
+	/* Ignore comment chars in trailing comments (e.g., Conflicts:) */
+	cutoff = sb->len - ignored_log_message_bytes(sb->buf, sb->len);
 
 	if (!memchr(sb->buf, candidates[0], sb->len)) {
 		free(comment_line_str_to_free);
@@ -700,7 +704,7 @@ static void adjust_comment_line_char(const struct strbuf *sb)
 	candidate = strchr(candidates, *p);
 	if (candidate)
 		*candidate = ' ';
-	for (p = sb->buf; *p; p++) {
+	for (p = sb->buf; p + 1 < sb->buf + cutoff; p++) {
 		if ((p[0] == '\n' || p[0] == '\r') && p[1]) {
 			candidate = strchr(candidates, p[1]);
 			if (candidate)

commit.c

@@ -31,6 +31,7 @@
 #include "parse.h"
 #include "object-file.h"
 #include "object-file-convert.h"
+#include "prio-queue.h"
 
 static struct commit_extra_header *read_commit_extra_header_lines(const char *buf, size_t len, const char **);
 
@@ -739,20 +740,27 @@ void commit_list_sort_by_date(struct commit_list **list)
 	commit_list_sort(list, commit_list_compare_by_date);
 }
 
-struct commit *pop_most_recent_commit(struct commit_list **list,
+struct commit *pop_most_recent_commit(struct prio_queue *queue,
 				      unsigned int mark)
 {
-	struct commit *ret = pop_commit(list);
+	struct commit *ret = prio_queue_peek(queue);
+	int get_pending = 1;
 	struct commit_list *parents = ret->parents;
 
 	while (parents) {
 		struct commit *commit = parents->item;
 		if (!repo_parse_commit(the_repository, commit) && !(commit->object.flags & mark)) {
 			commit->object.flags |= mark;
-			commit_list_insert_by_date(commit, list);
+			if (get_pending)
+				prio_queue_replace(queue, commit);
+			else
+				prio_queue_put(queue, commit);
+			get_pending = 0;
 		}
 		parents = parents->next;
 	}
+	if (get_pending)
+		prio_queue_get(queue);
 	return ret;
 }
 

commit.h

@@ -201,10 +201,10 @@ const char *repo_logmsg_reencode(struct repository *r,
 
 const char *skip_blank_lines(const char *msg);
 
-/** Removes the first commit from a list sorted by date, and adds all
- * of its parents.
- **/
-struct commit *pop_most_recent_commit(struct commit_list **list,
+struct prio_queue;
+
+/* Removes the first commit from a prio_queue and adds its parents. */
+struct commit *pop_most_recent_commit(struct prio_queue *queue,
 				      unsigned int mark);
 
 struct commit *pop_commit(struct commit_list **stack);

config.c

@@ -1534,9 +1534,11 @@ static int git_default_core_config(const char *var, const char *value,
 	    !strcmp(var, "core.commentstring")) {
 		if (!value)
 			return config_error_nonbool(var);
-		else if (!strcasecmp(value, "auto"))
+		else if (!strcasecmp(value, "auto")) {
 			auto_comment_line_char = 1;
-		else if (value[0]) {
+			FREE_AND_NULL(comment_line_str_to_free);
+			comment_line_str = "#";
+		} else if (value[0]) {
 			if (strchr(value, '\n'))
 				return error(_("%s cannot contain newline"), var);
 			comment_line_str = value;

fetch-pack.c

@@ -34,6 +34,7 @@
 #include "commit-graph.h"
 #include "sigchain.h"
 #include "mergesort.h"
+#include "prio-queue.h"
 
 static int transfer_unpack_limit = -1;
 static int fetch_unpack_limit = -1;
@@ -601,15 +602,15 @@ static int find_common(struct fetch_negotiator *negotiator,
 	return count ? retval : 0;
 }
 
-static struct commit_list *complete;
+static struct prio_queue complete = { compare_commits_by_commit_date };
 
 static int mark_complete(const struct object_id *oid)
 {
 	struct commit *commit = deref_without_lazy_fetch(oid, 1);
 
 	if (commit && !(commit->object.flags & COMPLETE)) {
 		commit->object.flags |= COMPLETE;
-		commit_list_insert(commit, &complete);
+		prio_queue_put(&complete, commit);
 	}
 	return 0;
 }
@@ -626,9 +627,12 @@ static int mark_complete_oid(const char *refname UNUSED,
 static void mark_recent_complete_commits(struct fetch_pack_args *args,
 					 timestamp_t cutoff)
 {
-	while (complete && cutoff <= complete->item->date) {
+	while (complete.nr) {
+		struct commit *item = prio_queue_peek(&complete);
+		if (item->date < cutoff)
+			break;
 		print_verbose(args, _("Marking %s as complete"),
-			      oid_to_hex(&complete->item->object.oid));
+			      oid_to_hex(&item->object.oid));
 		pop_most_recent_commit(&complete, COMPLETE);
 	}
 }
@@ -798,7 +802,6 @@ static void mark_complete_and_common_ref(struct fetch_negotiator *negotiator,
 		refs_for_each_rawref(get_main_ref_store(the_repository),
 				     mark_complete_oid, NULL);
 		for_each_cached_alternate(NULL, mark_alternate_complete);
-		commit_list_sort_by_date(&complete);
 		if (cutoff)
 			mark_recent_complete_commits(args, cutoff);
 	}

object-name.c

@@ -28,6 +28,7 @@
 #include "commit-reach.h"
 #include "date.h"
 #include "object-file-convert.h"
+#include "prio-queue.h"
 
 static int get_oid_oneline(struct repository *r, const char *, struct object_id *,
 			   const struct commit_list *);
@@ -1461,7 +1462,7 @@ static int get_oid_oneline(struct repository *r,
 			   const char *prefix, struct object_id *oid,
 			   const struct commit_list *list)
 {
-	struct commit_list *copy = NULL, **copy_tail = ©
+	struct prio_queue copy = { compare_commits_by_commit_date };
 	const struct commit_list *l;
 	int found = 0;
 	int negative = 0;
@@ -1483,9 +1484,9 @@ static int get_oid_oneline(struct repository *r,
 
 	for (l = list; l; l = l->next) {
 		l->item->object.flags |= ONELINE_SEEN;
-		copy_tail = &commit_list_insert(l->item, copy_tail)->next;
+		prio_queue_put(&copy, l->item);
 	}
-	while (copy) {
+	while (copy.nr) {
 		const char *p, *buf;
 		struct commit *commit;
 		int matches;
@@ -1507,7 +1508,7 @@ static int get_oid_oneline(struct repository *r,
 	regfree(&regex);
 	for (l = list; l; l = l->next)
 		clear_commit_marks(l->item, ONELINE_SEEN);
-	free_commit_list(copy);
+	clear_prio_queue(&copy);
 	return found ? 0 : -1;
 }
 
@@ -2061,7 +2062,6 @@ static enum get_oid_result get_oid_with_context_1(struct repository *repo,
 			cb.list = &list;
 			refs_for_each_ref(get_main_ref_store(repo), handle_one_ref, &cb);
 			refs_head_ref(get_main_ref_store(repo), handle_one_ref, &cb);
-			commit_list_sort_by_date(&list);
 			ret = get_oid_oneline(repo, name + 2, oid, list);
 
 			free_commit_list(list);

prio-queue.c

@@ -58,22 +58,10 @@ void prio_queue_put(struct prio_queue *queue, void *thing)
 	}
 }
 
-void *prio_queue_get(struct prio_queue *queue)
+static void sift_down_root(struct prio_queue *queue)
 {
-	void *result;
 	size_t ix, child;
 
-	if (!queue->nr)
-		return NULL;
-	if (!queue->compare)
-		return queue->array[--queue->nr].data; /* LIFO */
-
-	result = queue->array[0].data;
-	if (!--queue->nr)
-		return result;
-
-	queue->array[0] = queue->array[queue->nr];
-
 	/* Push down the one at the root */
 	for (ix = 0; ix * 2 + 1 < queue->nr; ix = child) {
 		child = ix * 2 + 1; /* left */
@@ -86,6 +74,23 @@ void *prio_queue_get(struct prio_queue *queue)
 
 		swap(queue, child, ix);
 	}
+}
+
+void *prio_queue_get(struct prio_queue *queue)
+{
+	void *result;
+
+	if (!queue->nr)
+		return NULL;
+	if (!queue->compare)
+		return queue->array[--queue->nr].data; /* LIFO */
+
+	result = queue->array[0].data;
+	if (!--queue->nr)
+		return result;
+
+	queue->array[0] = queue->array[queue->nr];
+	sift_down_root(queue);
 	return result;
 }
 
@@ -97,3 +102,17 @@ void *prio_queue_peek(struct prio_queue *queue)
 		return queue->array[queue->nr - 1].data;
 	return queue->array[0].data;
 }
+
+void prio_queue_replace(struct prio_queue *queue, void *thing)
+{
+	if (!queue->nr) {
+		prio_queue_put(queue, thing);
+	} else if (!queue->compare) {
+		queue->array[queue->nr - 1].ctr = queue->insertion_ctr++;
+		queue->array[queue->nr - 1].data = thing;
+	} else {
+		queue->array[0].ctr = queue->insertion_ctr++;
+		queue->array[0].data = thing;
+		sift_down_root(queue);
+	}
+}

prio-queue.h

@@ -52,6 +52,14 @@ void *prio_queue_get(struct prio_queue *);
  */
 void *prio_queue_peek(struct prio_queue *);
 
+/*
+ * Replace the "thing" that compares the smallest with a new "thing",
+ * like prio_queue_get()+prio_queue_put() would do, but in a more
+ * efficient way.  Does the same as prio_queue_put() if the queue is
+ * empty.
+ */
+void prio_queue_replace(struct prio_queue *queue, void *thing);
+
 void clear_prio_queue(struct prio_queue *);
 
 /* Reverse the LIFO elements */

t/meson.build

@@ -1116,6 +1116,7 @@ benchmarks = [
   'perf/p1450-fsck.sh',
   'perf/p1451-fsck-skip-list.sh',
   'perf/p1500-graph-walks.sh',
+  'perf/p1501-rev-parse-oneline.sh',
   'perf/p2000-sparse-operations.sh',
   'perf/p3400-rebase.sh',
   'perf/p3404-rebase-interactive.sh',

t/perf/p1501-rev-parse-oneline.sh

@@ -0,0 +1,71 @@
+#!/bin/sh
+
+test_description='Test :/ object name notation'
+
+. ./perf-lib.sh
+
+test_perf_fresh_repo
+
+#
+# Creates lots of merges to make history traversal costly.  In
+# particular it creates 2^($max_level-1)-1 2-way merges on top of
+# 2^($max_level-1) root commits.  E.g., the commit history looks like
+# this for a $max_level of 3:
+#
+#     _1_
+#    /   \
+#   2     3
+#  / \   / \
+# 4   5 6   7
+#
+# The numbers are the fast-import marks, which also are the commit
+# messages.  1 is the HEAD commit and a merge, 2 and 3 are also merges,
+# 4-7 are the root commits.
+#
+build_history () {
+	local max_level="$1" &&
+	local level="${2:-1}" &&
+	local mark="${3:-1}" &&
+	if test $level -eq $max_level
+	then
+		echo "reset refs/heads/master" &&
+		echo "from $ZERO_OID" &&
+		echo "commit refs/heads/master" &&
+		echo "mark :$mark" &&
+		echo "committer C <c@example.com> 1234567890 +0000" &&
+		echo "data <<EOF" &&
+		echo "$mark" &&
+		echo "EOF"
+	else
+		local level1=$((level+1)) &&
+		local mark1=$((2*mark)) &&
+		local mark2=$((2*mark+1)) &&
+		build_history $max_level $level1 $mark1 &&
+		build_history $max_level $level1 $mark2 &&
+		echo "commit refs/heads/master" &&
+		echo "mark :$mark" &&
+		echo "committer C <c@example.com> 1234567890 +0000" &&
+		echo "data <<EOF" &&
+		echo "$mark" &&
+		echo "EOF" &&
+		echo "from :$mark1" &&
+		echo "merge :$mark2"
+	fi
+}
+
+test_expect_success 'setup' '
+	build_history 16 | git fast-import &&
+	git log --format="%H %s" --reverse >commits &&
+	sed -n -e "s/ .*$//p" -e "q" <commits >expect &&
+	sed -n -e "s/^.* //p" -e "q" <commits >needle
+'
+
+test_perf "rev-parse :/$(cat needle)" '
+	git rev-parse :/$(cat needle) >actual
+'
+
+test_expect_success 'verify result' '
+	test_cmp expect actual
+'
+
+test_done

t/t3418-rebase-continue.sh

@@ -328,6 +328,19 @@ test_expect_success 'there is no --no-reschedule-failed-exec in an ongoing rebas
 	test_expect_code 129 git rebase --edit-todo --no-reschedule-failed-exec
 '
 
+test_expect_success 'no change in comment character due to conflicts markers with core.commentChar=auto' '
+	git checkout -b branch-a &&
+	test_commit A F1 &&
+	git checkout -b branch-b HEAD^ &&
+	test_commit B F1 &&
+	test_must_fail git rebase branch-a &&
+	printf "B\nA\n" >F1 &&
+	git add F1 &&
+	GIT_EDITOR="cat >actual" git -c core.commentChar=auto rebase --continue &&
+	# Check that "#" is still the comment character.
+	test_grep "^# Changes to be committed" actual
+'
+
 test_orig_head_helper () {
 	test_when_finished 'git rebase --abort &&
 		git checkout topic &&