diff --git a/Documentation/RelNotes/2.52.0.adoc b/Documentation/RelNotes/2.52.0.adoc
new file mode 100644
index 00000000000000..1919e039bd3401
--- /dev/null
+++ b/Documentation/RelNotes/2.52.0.adoc
@@ -0,0 +1,58 @@
+Git v2.52 Release Notes
+=======================
+
+UI, Workflows & Features
+------------------------
+
+
+Performance, Internal Implementation, Development Support etc.
+--------------------------------------------------------------
+
+ * string_list_split*() family of functions have been extended to
+   simplify common use cases.
+
+ * Arrays of strbuf is often a wrong data structure to use, and
+   strbuf_split*() family of functions that create them often have
+   better alternatives.  Update several code paths and replace
+   strbuf_split*().
+
+ * Revision traversal limited with pathspec, like "git log dir/*",
+   used to ignore changed-paths Bloom filter when the pathspec
+   contained wildcards; now they take advantage of the filter when
+   they can.
+
+Fixes since v2.51
+-----------------
+
+Unless otherwise noted, all the changes in 2.51.X maintenance track,
+including security updates, are included in this release.
+
+ * During interactive rebase, using 'drop' on a merge commit lead to
+   an error, which was incorrect.
+   (merge 4d491ade8f js/rebase-i-allow-drop-on-a-merge later to maint).
+
+ * "git refs migrate" to migrate the reflog entries from a refs
+   backend to another had a handful of bugs squashed.
+   (merge 465eff81de ps/reflog-migrate-fixes later to maint).
+
+ * "git remote rename origin upstream" failed to move origin/HEAD to
+   upstream/HEAD when origin/HEAD is unborn and performed other
+   renames extremely inefficiently, which has been corrected.
+   (merge 16c4fa26b9 ps/remote-rename-fix later to maint).
+
+ * "git describe" has been optimized by using better data structure.
+   (merge 08bb69d70f rs/describe-with-prio-queue later to maint).
+
+ * "git push" had a code path that led to BUG() but it should have
+   been a die(), as it is a response to a usual but invalid end-user
+   action to attempt pushing an object that does not exist.
+   (merge dfbfc2221b dl/push-missing-object-error later to maint).
+
+ * Various bugs about rename handling in "ort" merge strategy have
+   been fixed.
+   (merge f6ecb603ff en/ort-rename-fixes later to maint).
+
+ * Other code cleanup, docfix, build fix, etc.
+   (merge 823d537fa7 kh/doc-git-log-markup-fix later to maint).
+   (merge cf7efa4f33 rj/t6137-cygwin-fix later to maint).
+   (merge 529a60a885 ua/t1517-short-help-tests later to maint).
diff --git a/Documentation/config/log.adoc b/Documentation/config/log.adoc
index 16e00e8d296aa1..f20cc25cd7c3bf 100644
--- a/Documentation/config/log.adoc
+++ b/Documentation/config/log.adoc
@@ -23,14 +23,14 @@ be used.
 	Print out the ref names of any commits that are shown by the log
 	command. Possible values are:
 +
-----
+--
 `short`;; the ref name prefixes `refs/heads/`, `refs/tags/` and
 	`refs/remotes/` are not printed.
 `full`;; the full ref name (including prefix) are printed.
 `auto`;; if the output is going to a terminal,
 	the ref names are shown as if `short` were given, otherwise no ref
 	names are shown.
-----
+--
 +
 This is the same as the `--decorate` option of the `git log`.
 
diff --git a/Documentation/git-reflog.adoc b/Documentation/git-reflog.adoc
index 412f06b8fec57a..38af0c977a9b50 100644
--- a/Documentation/git-reflog.adoc
+++ b/Documentation/git-reflog.adoc
@@ -8,16 +8,17 @@ git-reflog - Manage reflog information
 
 SYNOPSIS
 --------
-[verse]
-'git reflog' [show] [<log-options>] [<ref>]
-'git reflog list'
-'git reflog expire' [--expire=<time>] [--expire-unreachable=<time>]
+[synopsis]
+git reflog [show] [<log-options>] [<ref>]
+git reflog list
+git reflog exists <ref>
+git reflog write <ref> <old-oid> <new-oid> <message>
+git reflog delete [--rewrite] [--updateref]
+	[--dry-run | -n] [--verbose] <ref>@{<specifier>}...
+git reflog drop [--all [--single-worktree] | <refs>...]
+git reflog expire [--expire=<time>] [--expire-unreachable=<time>]
 	[--rewrite] [--updateref] [--stale-fix]
 	[--dry-run | -n] [--verbose] [--all [--single-worktree] | <refs>...]
-'git reflog delete' [--rewrite] [--updateref]
-	[--dry-run | -n] [--verbose] <ref>@{<specifier>}...
-'git reflog drop' [--all [--single-worktree] | <refs>...]
-'git reflog exists' <ref>
 
 DESCRIPTION
 -----------
@@ -43,11 +44,15 @@ actions, and in addition the `HEAD` reflog records branch switching.
 
 The "list" subcommand lists all refs which have a corresponding reflog.
 
-The "expire" subcommand prunes older reflog entries. Entries older
-than `expire` time, or entries older than `expire-unreachable` time
-and not reachable from the current tip, are removed from the reflog.
-This is typically not used directly by end users -- instead, see
-linkgit:git-gc[1].
+The "exists" subcommand checks whether a ref has a reflog.  It exits
+with zero status if the reflog exists, and non-zero status if it does
+not.
+
+The "write" subcommand writes a single entry to the reflog of a given
+reference. This new entry is appended to the reflog and will thus become
+the most recent entry. The reference name must be fully qualified. Both the old
+and new object IDs must not be abbreviated and must point to existing objects.
+The reflog message gets normalized.
 
 The "delete" subcommand deletes single entries from the reflog, but
 not the reflog itself. Its argument must be an _exact_ entry (e.g. "`git
@@ -58,9 +63,11 @@ The "drop" subcommand completely removes the reflog for the specified
 references. This is in contrast to "expire" and "delete", both of which
 can be used to delete reflog entries, but not the reflog itself.
 
-The "exists" subcommand checks whether a ref has a reflog.  It exits
-with zero status if the reflog exists, and non-zero status if it does
-not.
+The "expire" subcommand prunes older reflog entries. Entries older
+than `expire` time, or entries older than `expire-unreachable` time
+and not reachable from the current tip, are removed from the reflog.
+This is typically not used directly by end users -- instead, see
+linkgit:git-gc[1].
 
 OPTIONS
 -------
@@ -71,18 +78,37 @@ Options for `show`
 `git reflog show` accepts any of the options accepted by `git log`.
 
 
+Options for `delete`
+~~~~~~~~~~~~~~~~~~~~
+
+`git reflog delete` accepts options `--updateref`, `--rewrite`, `-n`,
+`--dry-run`, and `--verbose`, with the same meanings as when they are
+used with `expire`.
+
+Options for `drop`
+~~~~~~~~~~~~~~~~~~
+
+`--all`::
+	Drop the reflogs of all references from all worktrees.
+
+`--single-worktree`::
+	By default when `--all` is specified, reflogs from all working
+	trees are dropped. This option limits the processing to reflogs
+	from the current working tree only.
+
+
 Options for `expire`
 ~~~~~~~~~~~~~~~~~~~~
 
---all::
+`--all`::
 	Process the reflogs of all references.
 
---single-worktree::
+`--single-worktree`::
 	By default when `--all` is specified, reflogs from all working
 	trees are processed. This option limits the processing to reflogs
 	from the current working tree only.
 
---expire=<time>::
+`--expire=<time>`::
 	Prune entries older than the specified time. If this option is
 	not specified, the expiration time is taken from the
 	configuration setting `gc.reflogExpire`, which in turn
@@ -90,7 +116,7 @@ Options for `expire`
 	of their age; `--expire=never` turns off pruning of reachable
 	entries (but see `--expire-unreachable`).
 
---expire-unreachable=<time>::
+`--expire-unreachable=<time>`::
 	Prune entries older than `<time>` that are not reachable from
 	the current tip of the branch. If this option is not
 	specified, the expiration time is taken from the configuration
@@ -100,17 +126,17 @@ Options for `expire`
 	turns off early pruning of unreachable entries (but see
 	`--expire`).
 
---updateref::
+`--updateref`::
 	Update the reference to the value of the top reflog entry (i.e.
 	<ref>@\{0\}) if the previous top entry was pruned.  (This
 	option is ignored for symbolic references.)
 
---rewrite::
+`--rewrite`::
 	If a reflog entry's predecessor is pruned, adjust its "old"
 	SHA-1 to be equal to the "new" SHA-1 field of the entry that
 	now precedes it.
 
---stale-fix::
+`--stale-fix`::
 	Prune any reflog entries that point to "broken commits". A
 	broken commit is a commit that is not reachable from any of
 	the reference tips and that refers, directly or indirectly, to
@@ -121,33 +147,15 @@ has the same cost as 'git prune'.  It is primarily intended to fix
 corruption caused by garbage collecting using older versions of Git,
 which didn't protect objects referred to by reflogs.
 
--n::
---dry-run::
+`-n`::
+`--dry-run`::
 	Do not actually prune any entries; just show what would have
 	been pruned.
 
---verbose::
+`--verbose`::
 	Print extra information on screen.
 
 
-Options for `delete`
-~~~~~~~~~~~~~~~~~~~~
-
-`git reflog delete` accepts options `--updateref`, `--rewrite`, `-n`,
-`--dry-run`, and `--verbose`, with the same meanings as when they are
-used with `expire`.
-
-Options for `drop`
-~~~~~~~~~~~~~~~~~~
-
---all::
-	Drop the reflogs of all references from all worktrees.
-
---single-worktree::
-	By default when `--all` is specified, reflogs from all working
-	trees are dropped. This option limits the processing to reflogs
-	from the current working tree only.
-
 GIT
 ---
 Part of the linkgit:git[1] suite
diff --git a/GIT-VERSION-GEN b/GIT-VERSION-GEN
index 64cbc583353607..b16db85e779ab2 100755
--- a/GIT-VERSION-GEN
+++ b/GIT-VERSION-GEN
@@ -1,6 +1,6 @@
 #!/bin/sh
 
-DEF_VER=v2.51.0
+DEF_VER=v2.51.GIT
 
 LF='
 '
diff --git a/RelNotes b/RelNotes
index 48f15770a4abb8..6d16c0077a11cb 120000
--- a/RelNotes
+++ b/RelNotes
@@ -1 +1 @@
-Documentation/RelNotes/2.51.0.adoc
\ No newline at end of file
+Documentation/RelNotes/2.52.0.adoc
\ No newline at end of file
diff --git a/builtin/blame.c b/builtin/blame.c
index 5b10e84b664228..2703820258d5f9 100644
--- a/builtin/blame.c
+++ b/builtin/blame.c
@@ -413,7 +413,7 @@ static void parse_color_fields(const char *s)
 	colorfield_nr = 0;
 
 	/* Ideally this would be stripped and split at the same time? */
-	string_list_split(&l, s, ',', -1);
+	string_list_split(&l, s, ",", -1);
 	ALLOC_GROW(colorfield, colorfield_nr + 1, colorfield_alloc);
 
 	for_each_string_list_item(item, &l) {
diff --git a/builtin/clean.c b/builtin/clean.c
index a1977b92dc89dd..38b67923a6205a 100644
--- a/builtin/clean.c
+++ b/builtin/clean.c
@@ -478,43 +478,39 @@ static int find_unique(const char *choice, struct menu_stuff *menu_stuff)
  */
 static int parse_choice(struct menu_stuff *menu_stuff,
 			int is_single,
-			struct strbuf input,
+			char *input,
 			int **chosen)
 {
-	struct strbuf **choice_list, **ptr;
+	struct string_list choice = STRING_LIST_INIT_NODUP;
+	struct string_list_item *item;
 	int nr = 0;
 	int i;
 
-	if (is_single) {
-		choice_list = strbuf_split_max(&input, '\n', 0);
-	} else {
-		char *p = input.buf;
-		do {
-			if (*p == ',')
-				*p = ' ';
-		} while (*p++);
-		choice_list = strbuf_split_max(&input, ' ', 0);
-	}
+	string_list_split_in_place_f(&choice, input,
+				     is_single ? "\n" : ", ", -1,
+				     STRING_LIST_SPLIT_TRIM);
 
-	for (ptr = choice_list; *ptr; ptr++) {
-		char *p;
-		int choose = 1;
+	for_each_string_list_item(item, &choice) {
+		const char *string;
+		int choose;
 		int bottom = 0, top = 0;
 		int is_range, is_number;
 
-		strbuf_trim(*ptr);
-		if (!(*ptr)->len)
+		string = item->string;
+		if (!*string)
 			continue;
 
 		/* Input that begins with '-'; unchoose */
-		if (*(*ptr)->buf == '-') {
+		if (string[0] == '-') {
 			choose = 0;
-			strbuf_remove((*ptr), 0, 1);
+			string++;
+		} else {
+			choose = 1;
 		}
 
 		is_range = 0;
 		is_number = 1;
-		for (p = (*ptr)->buf; *p; p++) {
+		for (const char *p = string; *p; p++) {
 			if ('-' == *p) {
 				if (!is_range) {
 					is_range = 1;
@@ -532,27 +528,27 @@ static int parse_choice(struct menu_stuff *menu_stuff,
 		}
 
 		if (is_number) {
-			bottom = atoi((*ptr)->buf);
+			bottom = atoi(string);
 			top = bottom;
 		} else if (is_range) {
-			bottom = atoi((*ptr)->buf);
+			bottom = atoi(string);
 			/* a range can be specified like 5-7 or 5- */
-			if (!*(strchr((*ptr)->buf, '-') + 1))
+			if (!*(strchr(string, '-') + 1))
 				top = menu_stuff->nr;
 			else
-				top = atoi(strchr((*ptr)->buf, '-') + 1);
-		} else if (!strcmp((*ptr)->buf, "*")) {
+				top = atoi(strchr(string, '-') + 1);
+		} else if (!strcmp(string, "*")) {
 			bottom = 1;
 			top = menu_stuff->nr;
 		} else {
-			bottom = find_unique((*ptr)->buf, menu_stuff);
+			bottom = find_unique(string, menu_stuff);
 			top = bottom;
 		}
 
 		if (top <= 0 || bottom <= 0 || top > menu_stuff->nr || bottom > top ||
 		    (is_single && bottom != top)) {
 			clean_print_color(CLEAN_COLOR_ERROR);
-			printf(_("Huh (%s)?\n"), (*ptr)->buf);
+			printf(_("Huh (%s)?\n"), string);
 			clean_print_color(CLEAN_COLOR_RESET);
 			continue;
 		}
@@ -561,7 +557,7 @@ static int parse_choice(struct menu_stuff *menu_stuff,
 			(*chosen)[i-1] = choose;
 	}
 
-	strbuf_list_free(choice_list);
+	string_list_clear(&choice, 0);
 
 	for (i = 0; i < menu_stuff->nr; i++)
 		nr += (*chosen)[i];
@@ -631,7 +627,7 @@ static int *list_and_choose(struct menu_opts *opts, struct menu_stuff *stuff)
 
 		nr = parse_choice(stuff,
 				  opts->flags & MENU_OPTS_SINGLETON,
-				  choice,
+				  choice.buf,
 				  &chosen);
 
 		if (opts->flags & MENU_OPTS_SINGLETON) {
@@ -679,12 +675,13 @@ static int filter_by_patterns_cmd(void)
 {
 	struct dir_struct dir = DIR_INIT;
 	struct strbuf confirm = STRBUF_INIT;
-	struct strbuf **ignore_list;
-	struct string_list_item *item;
 	struct pattern_list *pl;
 	int changed = -1, i;
 
 	for (;;) {
+		struct string_list ignore_list = STRING_LIST_INIT_NODUP;
+		struct string_list_item *item;
+
 		if (!del_list.nr)
 			break;
 
@@ -702,14 +699,15 @@ static int filter_by_patterns_cmd(void)
 			break;
 
 		pl = add_pattern_list(&dir, EXC_CMDL, "manual exclude");
-		ignore_list = strbuf_split_max(&confirm, ' ', 0);
 
-		for (i = 0; ignore_list[i]; i++) {
-			strbuf_trim(ignore_list[i]);
-			if (!ignore_list[i]->len)
-				continue;
+		string_list_split_in_place_f(&ignore_list, confirm.buf, " ", -1,
+					     STRING_LIST_SPLIT_TRIM);
 
-			add_pattern(ignore_list[i]->buf, "", 0, pl, -(i+1));
+		for (i = 0; i < ignore_list.nr; i++) {
+			item = &ignore_list.items[i];
+			if (!*item->string)
+				continue;
+			add_pattern(item->string, "", 0, pl, -(i+1));
 		}
 
 		changed = 0;
@@ -730,7 +728,7 @@ static int filter_by_patterns_cmd(void)
 			clean_print_color(CLEAN_COLOR_RESET);
 		}
 
-		strbuf_list_free(ignore_list);
+		string_list_clear(&ignore_list, 0);
 		dir_clear(&dir);
 	}
 
diff --git a/builtin/describe.c b/builtin/describe.c
index d7dd8139dec4b6..05409762108209 100644
--- a/builtin/describe.c
+++ b/builtin/describe.c
@@ -23,6 +23,7 @@
 #include "list-objects.h"
 #include "commit-slab.h"
 #include "wildmatch.h"
+#include "prio-queue.h"
 
 #define MAX_TAGS	(FLAG_BITS - 1)
 #define DEFAULT_CANDIDATES 10
@@ -249,24 +250,62 @@ static int compare_pt(const void *a_, const void *b_)
 	return 0;
 }
 
-static unsigned long finish_depth_computation(
-	struct commit_list **list,
-	struct possible_tag *best)
+struct lazy_queue {
+	struct prio_queue queue;
+	bool get_pending;
+};
+
+#define LAZY_QUEUE_INIT { { compare_commits_by_commit_date }, false }
+
+static void *lazy_queue_get(struct lazy_queue *queue)
+{
+	if (queue->get_pending)
+		prio_queue_get(&queue->queue);
+	else
+		queue->get_pending = true;
+	return prio_queue_peek(&queue->queue);
+}
+
+static void lazy_queue_put(struct lazy_queue *queue, void *thing)
+{
+	if (queue->get_pending)
+		prio_queue_replace(&queue->queue, thing);
+	else
+		prio_queue_put(&queue->queue, thing);
+	queue->get_pending = false;
+}
+
+static bool lazy_queue_empty(const struct lazy_queue *queue)
+{
+	return queue->queue.nr == (queue->get_pending ? 1 : 0);
+}
+
+static void lazy_queue_clear(struct lazy_queue *queue)
+{
+	clear_prio_queue(&queue->queue);
+	queue->get_pending = false;
+}
+
+static bool all_have_flag(const struct lazy_queue *queue, unsigned flag)
+{
+	for (size_t i = queue->get_pending ? 1 : 0; i < queue->queue.nr; i++) {
+		struct commit *commit = queue->queue.array[i].data;
+		if (!(commit->object.flags & flag))
+			return false;
+	}
+	return true;
+}
+
+static unsigned long finish_depth_computation(struct lazy_queue *queue,
+					      struct possible_tag *best)
 {
 	unsigned long seen_commits = 0;
-	while (*list) {
-		struct commit *c = pop_commit(list);
+	while (!lazy_queue_empty(queue)) {
+		struct commit *c = lazy_queue_get(queue);
 		struct commit_list *parents = c->parents;
 		seen_commits++;
 		if (c->object.flags & best->flag_within) {
-			struct commit_list *a = *list;
-			while (a) {
-				struct commit *i = a->item;
-				if (!(i->object.flags & best->flag_within))
-					break;
-				a = a->next;
-			}
-			if (!a)
+			if (all_have_flag(queue, best->flag_within))
 				break;
 		} else
 			best->depth++;
@@ -274,7 +313,7 @@ static unsigned long finish_depth_computation(
 			struct commit *p = parents->item;
 			repo_parse_commit(the_repository, p);
 			if (!(p->object.flags & SEEN))
-				commit_list_insert_by_date(p, list);
+				lazy_queue_put(queue, p);
 			p->object.flags |= c->object.flags;
 			parents = parents->next;
 		}
@@ -316,7 +355,7 @@ static void append_suffix(int depth, const struct object_id *oid, struct strbuf
 static void describe_commit(struct object_id *oid, struct strbuf *dst)
 {
 	struct commit *cmit, *gave_up_on = NULL;
-	struct commit_list *list;
+	struct lazy_queue queue = LAZY_QUEUE_INIT;
 	struct commit_name *n;
 	struct possible_tag all_matches[MAX_TAGS];
 	unsigned int match_cnt = 0, annotated_cnt = 0, cur_match;
@@ -359,11 +398,10 @@ static void describe_commit(struct object_id *oid, struct strbuf *dst)
 		have_util = 1;
 	}
 
-	list = NULL;
 	cmit->object.flags = SEEN;
-	commit_list_insert(cmit, &list);
-	while (list) {
-		struct commit *c = pop_commit(&list);
+	lazy_queue_put(&queue, cmit);
+	while (!lazy_queue_empty(&queue)) {
+		struct commit *c = lazy_queue_get(&queue);
 		struct commit_list *parents = c->parents;
 		struct commit_name **slot;
 
@@ -397,7 +435,7 @@ static void describe_commit(struct object_id *oid, struct strbuf *dst)
 				t->depth++;
 		}
 		/* Stop if last remaining path already covered by best candidate(s) */
-		if (annotated_cnt && !list) {
+		if (annotated_cnt && lazy_queue_empty(&queue)) {
 			int best_depth = INT_MAX;
 			unsigned best_within = 0;
 			for (cur_match = 0; cur_match < match_cnt; cur_match++) {
@@ -420,7 +458,7 @@ static void describe_commit(struct object_id *oid, struct strbuf *dst)
 			struct commit *p = parents->item;
 			repo_parse_commit(the_repository, p);
 			if (!(p->object.flags & SEEN))
-				commit_list_insert_by_date(p, &list);
+				lazy_queue_put(&queue, p);
 			p->object.flags |= c->object.flags;
 			parents = parents->next;
 
@@ -435,6 +473,7 @@ static void describe_commit(struct object_id *oid, struct strbuf *dst)
 			strbuf_add_unique_abbrev(dst, cmit_oid, abbrev);
 			if (suffix)
 				strbuf_addstr(dst, suffix);
+			lazy_queue_clear(&queue);
 			return;
 		}
 		if (unannotated_cnt)
@@ -450,11 +489,11 @@ static void describe_commit(struct object_id *oid, struct strbuf *dst)
 	QSORT(all_matches, match_cnt, compare_pt);
 
 	if (gave_up_on) {
-		commit_list_insert_by_date(gave_up_on, &list);
+		lazy_queue_put(&queue, gave_up_on);
 		seen_commits--;
 	}
-	seen_commits += finish_depth_computation(&list, &all_matches[0]);
-	free_commit_list(list);
+	seen_commits += finish_depth_computation(&queue, &all_matches[0]);
+	lazy_queue_clear(&queue);
 
 	if (debug) {
 		static int label_width = -1;
diff --git a/builtin/fsck.c b/builtin/fsck.c
index 543a2cdb5cd864..d2eb9d4fbe922b 100644
--- a/builtin/fsck.c
+++ b/builtin/fsck.c
@@ -503,13 +503,12 @@ static void fsck_handle_reflog_oid(const char *refname, struct object_id *oid,
 	}
 }
 
-static int fsck_handle_reflog_ent(struct object_id *ooid, struct object_id *noid,
+static int fsck_handle_reflog_ent(const char *refname,
+				  struct object_id *ooid, struct object_id *noid,
 				  const char *email UNUSED,
 				  timestamp_t timestamp, int tz UNUSED,
-				  const char *message UNUSED, void *cb_data)
+				  const char *message UNUSED, void *cb_data UNUSED)
 {
-	const char *refname = cb_data;
-
 	if (verbose)
 		fprintf_ln(stderr, _("Checking reflog %s->%s"),
 			   oid_to_hex(ooid), oid_to_hex(noid));
@@ -526,7 +525,7 @@ static int fsck_handle_reflog(const char *logname, void *cb_data)
 	strbuf_worktree_ref(cb_data, &refname, logname);
 	refs_for_each_reflog_ent(get_main_ref_store(the_repository),
 				 refname.buf, fsck_handle_reflog_ent,
-				 refname.buf);
+				 NULL);
 	strbuf_release(&refname);
 	return 0;
 }
diff --git a/builtin/gc.c b/builtin/gc.c
index 0edd94a76f2958..03ae4926b20982 100644
--- a/builtin/gc.c
+++ b/builtin/gc.c
@@ -312,7 +312,8 @@ struct count_reflog_entries_data {
 	size_t limit;
 };
 
-static int count_reflog_entries(struct object_id *old_oid, struct object_id *new_oid,
+static int count_reflog_entries(const char *refname UNUSED,
+				struct object_id *old_oid, struct object_id *new_oid,
 				const char *committer, timestamp_t timestamp,
 				int tz, const char *msg, void *cb_data)
 {
diff --git a/builtin/merge-tree.c b/builtin/merge-tree.c
index 203f0e6456a751..1c063d9a41a695 100644
--- a/builtin/merge-tree.c
+++ b/builtin/merge-tree.c
@@ -619,32 +619,34 @@ int cmd_merge_tree(int argc,
 			    "--merge-base", "--stdin");
 		line_termination = '\0';
 		while (strbuf_getline_lf(&buf, stdin) != EOF) {
-			struct strbuf **split;
+			struct string_list split = STRING_LIST_INIT_NODUP;
 			const char *input_merge_base = NULL;
 
-			split = strbuf_split(&buf, ' ');
-			if (!split[0] || !split[1])
+			string_list_split_in_place_f(&split, buf.buf, " ", -1,
+						     STRING_LIST_SPLIT_TRIM);
+
+			if (split.nr < 2)
 				die(_("malformed input line: '%s'."), buf.buf);
-			strbuf_rtrim(split[0]);
-			strbuf_rtrim(split[1]);
 
 			/* parse the merge-base */
-			if (!strcmp(split[1]->buf, "--")) {
-				input_merge_base = split[0]->buf;
+			if (!strcmp(split.items[1].string, "--")) {
+				input_merge_base = split.items[0].string;
 			}
 
-			if (input_merge_base && split[2] && split[3] && !split[4]) {
-				strbuf_rtrim(split[2]);
-				strbuf_rtrim(split[3]);
-				real_merge(&o, input_merge_base, split[2]->buf, split[3]->buf, prefix);
-			} else if (!input_merge_base && !split[2]) {
-				real_merge(&o, NULL, split[0]->buf, split[1]->buf, prefix);
+			if (input_merge_base && split.nr == 4) {
+				real_merge(&o, input_merge_base,
+					   split.items[2].string, split.items[3].string,
+					   prefix);
+			} else if (!input_merge_base && split.nr == 2) {
+				real_merge(&o, NULL,
+					   split.items[0].string, split.items[1].string,
+					   prefix);
 			} else {
 				die(_("malformed input line: '%s'."), buf.buf);
 			}
 			maybe_flush_or_die(stdout, "stdout");
 
-			strbuf_list_free(split);
+			string_list_clear(&split, 0);
 		}
 		strbuf_release(&buf);
 
diff --git a/builtin/merge.c b/builtin/merge.c
index ce880e6ccb74bc..c3810c9cb23e60 100644
--- a/builtin/merge.c
+++ b/builtin/merge.c
@@ -875,7 +875,7 @@ static void add_strategies(const char *string, unsigned attr)
 	if (string) {
 		struct string_list list = STRING_LIST_INIT_DUP;
 		struct string_list_item *item;
-		string_list_split(&list, string, ' ', -1);
+		string_list_split(&list, string, " ", -1);
 		for_each_string_list_item(item, &list)
 			append_strategy(get_strategy(item->string));
 		string_list_clear(&list, 0);
diff --git a/builtin/notes.c b/builtin/notes.c
index 6fb4144da3ead5..9af602bdd7b402 100644
--- a/builtin/notes.c
+++ b/builtin/notes.c
@@ -376,18 +376,19 @@ static int notes_copy_from_stdin(int force, const char *rewrite_cmd)
 
 	while (strbuf_getline_lf(&buf, stdin) != EOF) {
 		struct object_id from_obj, to_obj;
-		struct strbuf **split;
+		struct string_list split = STRING_LIST_INIT_NODUP;
 		int err;
 
-		split = strbuf_split(&buf, ' ');
-		if (!split[0] || !split[1])
+		string_list_split_in_place_f(&split, buf.buf, " ", -1,
+					     STRING_LIST_SPLIT_TRIM);
+		if (split.nr < 2)
 			die(_("malformed input line: '%s'."), buf.buf);
-		strbuf_rtrim(split[0]);
-		strbuf_rtrim(split[1]);
-		if (repo_get_oid(the_repository, split[0]->buf, &from_obj))
-			die(_("failed to resolve '%s' as a valid ref."), split[0]->buf);
-		if (repo_get_oid(the_repository, split[1]->buf, &to_obj))
-			die(_("failed to resolve '%s' as a valid ref."), split[1]->buf);
+		if (repo_get_oid(the_repository, split.items[0].string, &from_obj))
+			die(_("failed to resolve '%s' as a valid ref."),
+			    split.items[0].string);
+		if (repo_get_oid(the_repository, split.items[1].string, &to_obj))
+			die(_("failed to resolve '%s' as a valid ref."),
+			    split.items[1].string);
 
 		if (rewrite_cmd)
 			err = copy_note_for_rewrite(c, &from_obj, &to_obj);
@@ -397,11 +398,11 @@ static int notes_copy_from_stdin(int force, const char *rewrite_cmd)
 
 		if (err) {
 			error(_("failed to copy notes from '%s' to '%s'"),
-			      split[0]->buf, split[1]->buf);
+			      split.items[0].string, split.items[1].string);
 			ret = 1;
 		}
 
-		strbuf_list_free(split);
+		string_list_clear(&split, 0);
 	}
 
 	if (!rewrite_cmd) {
diff --git a/builtin/reflog.c b/builtin/reflog.c
index 1db26aa65f2fdd..c8f6b93d60b1e8 100644
--- a/builtin/reflog.c
+++ b/builtin/reflog.c
@@ -3,6 +3,8 @@
 #include "builtin.h"
 #include "config.h"
 #include "gettext.h"
+#include "hex.h"
+#include "odb.h"
 #include "revision.h"
 #include "reachable.h"
 #include "wildmatch.h"
@@ -17,21 +19,24 @@
 #define BUILTIN_REFLOG_LIST_USAGE \
 	N_("git reflog list")
 
-#define BUILTIN_REFLOG_EXPIRE_USAGE \
-	N_("git reflog expire [--expire=<time>] [--expire-unreachable=<time>]\n" \
-	   "                  [--rewrite] [--updateref] [--stale-fix]\n" \
-	   "                  [--dry-run | -n] [--verbose] [--all [--single-worktree] | <refs>...]")
+#define BUILTIN_REFLOG_EXISTS_USAGE \
+	N_("git reflog exists <ref>")
+
+#define BUILTIN_REFLOG_WRITE_USAGE \
+	N_("git reflog write <ref> <old-oid> <new-oid> <message>")
 
 #define BUILTIN_REFLOG_DELETE_USAGE \
 	N_("git reflog delete [--rewrite] [--updateref]\n" \
 	   "                  [--dry-run | -n] [--verbose] <ref>@{<specifier>}...")
 
-#define BUILTIN_REFLOG_EXISTS_USAGE \
-	N_("git reflog exists <ref>")
-
 #define BUILTIN_REFLOG_DROP_USAGE \
 	N_("git reflog drop [--all [--single-worktree] | <refs>...]")
 
+#define BUILTIN_REFLOG_EXPIRE_USAGE \
+	N_("git reflog expire [--expire=<time>] [--expire-unreachable=<time>]\n" \
+	   "                  [--rewrite] [--updateref] [--stale-fix]\n" \
+	   "                  [--dry-run | -n] [--verbose] [--all [--single-worktree] | <refs>...]")
+
 static const char *const reflog_show_usage[] = {
 	BUILTIN_REFLOG_SHOW_USAGE,
 	NULL,
@@ -42,9 +47,14 @@ static const char *const reflog_list_usage[] = {
 	NULL,
 };
 
-static const char *const reflog_expire_usage[] = {
-	BUILTIN_REFLOG_EXPIRE_USAGE,
-	NULL
+static const char *const reflog_exists_usage[] = {
+	BUILTIN_REFLOG_EXISTS_USAGE,
+	NULL,
+};
+
+static const char *const reflog_write_usage[] = {
+	BUILTIN_REFLOG_WRITE_USAGE,
+	NULL,
 };
 
 static const char *const reflog_delete_usage[] = {
@@ -52,23 +62,24 @@ static const char *const reflog_delete_usage[] = {
 	NULL
 };
 
-static const char *const reflog_exists_usage[] = {
-	BUILTIN_REFLOG_EXISTS_USAGE,
-	NULL,
-};
-
 static const char *const reflog_drop_usage[] = {
 	BUILTIN_REFLOG_DROP_USAGE,
 	NULL,
 };
 
+static const char *const reflog_expire_usage[] = {
+	BUILTIN_REFLOG_EXPIRE_USAGE,
+	NULL
+};
+
 static const char *const reflog_usage[] = {
 	BUILTIN_REFLOG_SHOW_USAGE,
 	BUILTIN_REFLOG_LIST_USAGE,
-	BUILTIN_REFLOG_EXPIRE_USAGE,
+	BUILTIN_REFLOG_EXISTS_USAGE,
+	BUILTIN_REFLOG_WRITE_USAGE,
 	BUILTIN_REFLOG_DELETE_USAGE,
 	BUILTIN_REFLOG_DROP_USAGE,
-	BUILTIN_REFLOG_EXISTS_USAGE,
+	BUILTIN_REFLOG_EXPIRE_USAGE,
 	NULL
 };
 
@@ -395,6 +406,59 @@ static int cmd_reflog_drop(int argc, const char **argv, const char *prefix,
 	return ret;
 }
 
+static int cmd_reflog_write(int argc, const char **argv, const char *prefix,
+			    struct repository *repo)
+{
+	const struct option options[] = {
+		OPT_END()
+	};
+	struct object_id old_oid, new_oid;
+	struct strbuf err = STRBUF_INIT;
+	struct ref_transaction *tx;
+	const char *ref, *message;
+	int ret;
+
+	argc = parse_options(argc, argv, prefix, options, reflog_write_usage, 0);
+	if (argc != 4)
+		usage_with_options(reflog_write_usage, options);
+
+	ref = argv[0];
+	if (!is_root_ref(ref) && check_refname_format(ref, 0))
+		die(_("invalid reference name: %s"), ref);
+
+	ret = get_oid_hex_algop(argv[1], &old_oid, repo->hash_algo);
+	if (ret)
+		die(_("invalid old object ID: '%s'"), argv[1]);
+	if (!is_null_oid(&old_oid) && !odb_has_object(repo->objects, &old_oid, 0))
+		die(_("old object '%s' does not exist"), argv[1]);
+
+	ret = get_oid_hex_algop(argv[2], &new_oid, repo->hash_algo);
+	if (ret)
+		die(_("invalid new object ID: '%s'"), argv[2]);
+	if (!is_null_oid(&new_oid) && !odb_has_object(repo->objects, &new_oid, 0))
+		die(_("new object '%s' does not exist"), argv[2]);
+
+	message = argv[3];
+
+	tx = ref_store_transaction_begin(get_main_ref_store(repo), 0, &err);
+	if (!tx)
+		die(_("cannot start transaction: %s"), err.buf);
+
+	ret = ref_transaction_update_reflog(tx, ref, &new_oid, &old_oid,
+					    git_committer_info(0),
+					    message, 0, &err);
+	if (ret)
+		die(_("cannot queue reflog update: %s"), err.buf);
+
+	ret = ref_transaction_commit(tx, &err);
+	if (ret)
+		die(_("cannot commit reflog update: %s"), err.buf);
+
+	ref_transaction_free(tx);
+	strbuf_release(&err);
+	return 0;
+}
+
 /*
  * main "reflog"
  */
@@ -407,10 +471,11 @@ int cmd_reflog(int argc,
 	struct option options[] = {
 		OPT_SUBCOMMAND("show", &fn, cmd_reflog_show),
 		OPT_SUBCOMMAND("list", &fn, cmd_reflog_list),
-		OPT_SUBCOMMAND("expire", &fn, cmd_reflog_expire),
-		OPT_SUBCOMMAND("delete", &fn, cmd_reflog_delete),
 		OPT_SUBCOMMAND("exists", &fn, cmd_reflog_exists),
+		OPT_SUBCOMMAND("write", &fn, cmd_reflog_write),
+		OPT_SUBCOMMAND("delete", &fn, cmd_reflog_delete),
 		OPT_SUBCOMMAND("drop", &fn, cmd_reflog_drop),
+		OPT_SUBCOMMAND("expire", &fn, cmd_reflog_expire),
 		OPT_END()
 	};
 
diff --git a/builtin/remote.c b/builtin/remote.c
index 8961ae6a8973c7..8a7ed4299a4b51 100644
--- a/builtin/remote.c
+++ b/builtin/remote.c
@@ -1,9 +1,11 @@
 #define USE_THE_REPOSITORY_VARIABLE
-#define DISABLE_SIGN_COMPARE_WARNINGS
 
 #include "builtin.h"
+#include "advice.h"
 #include "config.h"
+#include "date.h"
 #include "gettext.h"
+#include "ident.h"
 #include "parse-options.h"
 #include "path.h"
 #include "transport.h"
@@ -182,7 +184,6 @@ static int add(int argc, const char **argv, const char *prefix,
 	struct remote *remote;
 	struct strbuf buf = STRBUF_INIT, buf2 = STRBUF_INIT;
 	const char *name, *url;
-	int i;
 	int result = 0;
 
 	struct option options[] = {
@@ -233,7 +234,7 @@ static int add(int argc, const char **argv, const char *prefix,
 		strbuf_addf(&buf, "remote.%s.fetch", name);
 		if (track.nr == 0)
 			string_list_append(&track, "*");
-		for (i = 0; i < track.nr; i++) {
+		for (size_t i = 0; i < track.nr; i++) {
 			add_branch(buf.buf, track.items[i].string,
 				   name, mirror, &buf2);
 		}
@@ -612,53 +613,169 @@ static int add_branch_for_removal(const char *refname,
 struct rename_info {
 	const char *old_name;
 	const char *new_name;
-	struct string_list *remote_branches;
-	uint32_t symrefs_nr;
+	struct ref_transaction *transaction;
+	struct progress *progress;
+	struct strbuf *err;
+	uint32_t progress_nr;
+	uint64_t index;
 };
 
-static int read_remote_branches(const char *refname, const char *referent UNUSED,
-				const struct object_id *oid UNUSED,
-				int flags UNUSED, void *cb_data)
+static void compute_renamed_ref(struct rename_info *rename,
+				const char *refname,
+				struct strbuf *out)
+{
+	strbuf_reset(out);
+	strbuf_addstr(out, refname);
+	strbuf_splice(out, strlen("refs/remotes/"), strlen(rename->old_name),
+		      rename->new_name, strlen(rename->new_name));
+}
+
+static int rename_one_reflog_entry(const char *old_refname,
+				   struct object_id *old_oid,
+				   struct object_id *new_oid,
+				   const char *committer,
+				   timestamp_t timestamp, int tz,
+				   const char *msg, void *cb_data)
 {
 	struct rename_info *rename = cb_data;
-	struct strbuf buf = STRBUF_INIT;
-	struct string_list_item *item;
-	int flag;
-	const char *symref;
-
-	strbuf_addf(&buf, "refs/remotes/%s/", rename->old_name);
-	if (starts_with(refname, buf.buf)) {
-		item = string_list_append(rename->remote_branches, refname);
-		symref = refs_resolve_ref_unsafe(get_main_ref_store(the_repository),
-						 refname, RESOLVE_REF_READING,
-						 NULL, &flag);
-		if (symref && (flag & REF_ISSYMREF)) {
-			item->util = xstrdup(symref);
-			rename->symrefs_nr++;
-		} else {
-			item->util = NULL;
-		}
+	struct strbuf new_refname = STRBUF_INIT;
+	struct strbuf identity = STRBUF_INIT;
+	struct strbuf name = STRBUF_INIT;
+	struct strbuf mail = STRBUF_INIT;
+	struct ident_split ident;
+	const char *date;
+	int error;
+
+	compute_renamed_ref(rename, old_refname, &new_refname);
+
+	if (split_ident_line(&ident, committer, strlen(committer)) < 0) {
+		error = -1;
+		goto out;
 	}
-	strbuf_release(&buf);
 
-	return 0;
+	strbuf_add(&name, ident.name_begin, ident.name_end - ident.name_begin);
+	strbuf_add(&mail, ident.mail_begin, ident.mail_end - ident.mail_begin);
+
+	date = show_date(timestamp, tz, DATE_MODE(NORMAL));
+	strbuf_addstr(&identity, fmt_ident(name.buf, mail.buf,
+					  WANT_BLANK_IDENT, date, 0));
+
+	error = ref_transaction_update_reflog(rename->transaction, new_refname.buf,
+					      new_oid, old_oid, identity.buf, msg,
+					      rename->index++, rename->err);
+
+out:
+	strbuf_release(&new_refname);
+	strbuf_release(&identity);
+	strbuf_release(&name);
+	strbuf_release(&mail);
+	return error;
+}
+
+static int rename_one_reflog(const char *old_refname,
+			     const struct object_id *old_oid,
+			     struct rename_info *rename)
+{
+	struct strbuf new_refname = STRBUF_INIT;
+	struct strbuf message = STRBUF_INIT;
+	int error;
+
+	if (!refs_reflog_exists(get_main_ref_store(the_repository), old_refname))
+		return 0;
+
+	error = refs_for_each_reflog_ent(get_main_ref_store(the_repository),
+					 old_refname, rename_one_reflog_entry, rename);
+	if (error < 0)
+		goto out;
+
+	compute_renamed_ref(rename, old_refname, &new_refname);
+
+	/*
+	 * Manually write the reflog entry for the now-renamed ref. We cannot
+	 * rely on `rename_one_ref()` to do this for us as that would screw
+	 * over order in which reflog entries are being written.
+	 *
+	 * Furthermore, we only append the entry in case the reference
+	 * resolves. Missing references shouldn't have reflogs anyway.
+	 */
+	strbuf_addf(&message, "remote: renamed %s to %s", old_refname,
+		    new_refname.buf);
+
+	error = ref_transaction_update_reflog(rename->transaction, new_refname.buf,
+					      old_oid, old_oid, git_committer_info(0),
+					      message.buf, rename->index++, rename->err);
+	if (error < 0)
+		return error;
+
+out:
+	strbuf_release(&new_refname);
+	strbuf_release(&message);
+	return error;
+}
+
+static int rename_one_ref(const char *old_refname, const char *referent,
+			  const struct object_id *oid,
+			  int flags, void *cb_data)
+{
+	struct strbuf new_referent = STRBUF_INIT;
+	struct strbuf new_refname = STRBUF_INIT;
+	struct rename_info *rename = cb_data;
+	int error;
+
+	compute_renamed_ref(rename, old_refname, &new_refname);
+
+	if (flags & REF_ISSYMREF) {
+		/*
+		 * Stupidly enough `referent` is not pointing to the immediate
+		 * target of a symref, but it's the recursively resolved value.
+		 * So symrefs pointing to symrefs would be misresolved, and
+		 * unborn symrefs don't have any value for the `referent` at all.
+		 */
+		referent = refs_resolve_ref_unsafe(get_main_ref_store(the_repository),
+						   old_refname, RESOLVE_REF_NO_RECURSE,
+						   NULL, NULL);
+		compute_renamed_ref(rename, referent, &new_referent);
+		oid = NULL;
+	}
+
+	error = ref_transaction_delete(rename->transaction, old_refname,
+				       oid, referent, REF_NO_DEREF, NULL, rename->err);
+	if (error < 0)
+		goto out;
+
+	error = ref_transaction_update(rename->transaction, new_refname.buf, oid, null_oid(the_hash_algo),
+				       (flags & REF_ISSYMREF) ? new_referent.buf : NULL, NULL,
+				       REF_SKIP_CREATE_REFLOG | REF_NO_DEREF | REF_SKIP_OID_VERIFICATION,
+				       NULL, rename->err);
+	if (error < 0)
+		goto out;
+
+	error = rename_one_reflog(old_refname, oid, rename);
+	if (error < 0)
+		goto out;
+
+	display_progress(rename->progress, ++rename->progress_nr);
+
+out:
+	strbuf_release(&new_referent);
+	strbuf_release(&new_refname);
+	return error;
 }
 
 static int migrate_file(struct remote *remote)
 {
 	struct strbuf buf = STRBUF_INIT;
-	int i;
 
 	strbuf_addf(&buf, "remote.%s.url", remote->name);
-	for (i = 0; i < remote->url.nr; i++)
+	for (size_t i = 0; i < remote->url.nr; i++)
 		repo_config_set_multivar(the_repository, buf.buf, remote->url.v[i], "^$", 0);
 	strbuf_reset(&buf);
 	strbuf_addf(&buf, "remote.%s.push", remote->name);
-	for (i = 0; i < remote->push.nr; i++)
+	for (int i = 0; i < remote->push.nr; i++)
 		repo_config_set_multivar(the_repository, buf.buf, remote->push.items[i].raw, "^$", 0);
 	strbuf_reset(&buf);
 	strbuf_addf(&buf, "remote.%s.fetch", remote->name);
-	for (i = 0; i < remote->fetch.nr; i++)
+	for (int i = 0; i < remote->fetch.nr; i++)
 		repo_config_set_multivar(the_repository, buf.buf, remote->fetch.items[i].raw, "^$", 0);
 #ifndef WITH_BREAKING_CHANGES
 	if (remote->origin == REMOTE_REMOTES)
@@ -730,6 +847,14 @@ static void handle_push_default(const char* old_name, const char* new_name)
 	strbuf_release(&push_default.origin);
 }
 
+static const char conflicting_remote_refs_advice[] = N_(
+	"The remote you are trying to rename has conflicting references in the\n"
+	"new target refspec. This is most likely caused by you trying to nest\n"
+	"a remote into itself, e.g. by renaming 'parent' into 'parent/child'\n"
+	"or by unnesting a remote, e.g. the other way round.\n"
+	"\n"
+	"If that is the case, you can address this by first renaming the\n"
+	"remote to a different name.\n");
 
 static int mv(int argc, const char **argv, const char *prefix,
 	      struct repository *repo UNUSED)
@@ -741,11 +866,11 @@ static int mv(int argc, const char **argv, const char *prefix,
 	};
 	struct remote *oldremote, *newremote;
 	struct strbuf buf = STRBUF_INIT, buf2 = STRBUF_INIT, buf3 = STRBUF_INIT,
-		old_remote_context = STRBUF_INIT;
-	struct string_list remote_branches = STRING_LIST_INIT_DUP;
-	struct rename_info rename;
-	int i, refs_renamed_nr = 0, refspec_updated = 0;
-	struct progress *progress = NULL;
+		old_remote_context = STRBUF_INIT, err = STRBUF_INIT;
+	struct rename_info rename = {
+		.err = &err,
+	};
+	int refspecs_need_update = 0;
 	int result = 0;
 
 	argc = parse_options(argc, argv, prefix, options,
@@ -756,8 +881,6 @@ static int mv(int argc, const char **argv, const char *prefix,
 
 	rename.old_name = argv[0];
 	rename.new_name = argv[1];
-	rename.remote_branches = &remote_branches;
-	rename.symrefs_nr = 0;
 
 	oldremote = remote_get(rename.old_name);
 	if (!remote_is_configured(oldremote, 1)) {
@@ -785,19 +908,50 @@ static int mv(int argc, const char **argv, const char *prefix,
 		goto out;
 	}
 
+	strbuf_addf(&old_remote_context, ":refs/remotes/%s/", rename.old_name);
+
+	for (int i = 0; i < oldremote->fetch.nr && !refspecs_need_update; i++)
+		refspecs_need_update = !!strstr(oldremote->fetch.items[i].raw,
+						old_remote_context.buf);
+
+	if (refspecs_need_update) {
+		rename.transaction = ref_store_transaction_begin(get_main_ref_store(the_repository),
+							       0, &err);
+		if (!rename.transaction)
+			goto out;
+
+		if (show_progress)
+			rename.progress = start_delayed_progress(the_repository,
+								 _("Renaming remote references"), 0);
+
+		strbuf_reset(&buf);
+		strbuf_addf(&buf, "refs/remotes/%s/", rename.old_name);
+
+		result = refs_for_each_rawref_in(get_main_ref_store(the_repository), buf.buf,
+				rename_one_ref, &rename);
+		if (result < 0)
+			die(_("queueing remote ref renames failed: %s"), rename.err->buf);
+
+		result = ref_transaction_prepare(rename.transaction, &err);
+		if (result < 0) {
+			error("renaming remote references failed: %s", err.buf);
+			if (result == REF_TRANSACTION_ERROR_NAME_CONFLICT)
+				advise(conflicting_remote_refs_advice);
+			die(NULL);
+		}
+	}
+
 	if (oldremote->fetch.nr) {
 		strbuf_reset(&buf);
 		strbuf_addf(&buf, "remote.%s.fetch", rename.new_name);
 		repo_config_set_multivar(the_repository, buf.buf, NULL, NULL, CONFIG_FLAGS_MULTI_REPLACE);
-		strbuf_addf(&old_remote_context, ":refs/remotes/%s/", rename.old_name);
-		for (i = 0; i < oldremote->fetch.nr; i++) {
+		for (int i = 0; i < oldremote->fetch.nr; i++) {
 			char *ptr;
 
 			strbuf_reset(&buf2);
 			strbuf_addstr(&buf2, oldremote->fetch.items[i].raw);
 			ptr = strstr(buf2.buf, old_remote_context.buf);
 			if (ptr) {
-				refspec_updated = 1;
 				strbuf_splice(&buf2,
 					      ptr-buf2.buf + strlen(":refs/remotes/"),
 					      strlen(rename.old_name), rename.new_name,
@@ -813,7 +967,7 @@ static int mv(int argc, const char **argv, const char *prefix,
 	}
 
 	read_branches();
-	for (i = 0; i < branch_list.nr; i++) {
+	for (size_t i = 0; i < branch_list.nr; i++) {
 		struct string_list_item *item = branch_list.items + i;
 		struct branch_info *info = item->util;
 		if (info->remote_name && !strcmp(info->remote_name, rename.old_name)) {
@@ -828,83 +982,23 @@ static int mv(int argc, const char **argv, const char *prefix,
 		}
 	}
 
-	if (!refspec_updated)
-		goto out;
-
-	/*
-	 * First remove symrefs, then rename the rest, finally create
-	 * the new symrefs.
-	 */
-	refs_for_each_ref(get_main_ref_store(the_repository),
-			  read_remote_branches, &rename);
-	if (show_progress) {
-		/*
-		 * Count symrefs twice, since "renaming" them is done by
-		 * deleting and recreating them in two separate passes.
-		 */
-		progress = start_progress(the_repository,
-					  _("Renaming remote references"),
-					  rename.remote_branches->nr + rename.symrefs_nr);
-	}
-	for (i = 0; i < remote_branches.nr; i++) {
-		struct string_list_item *item = remote_branches.items + i;
-		struct strbuf referent = STRBUF_INIT;
-
-		if (refs_read_symbolic_ref(get_main_ref_store(the_repository), item->string,
-					   &referent))
-			continue;
-		if (refs_delete_ref(get_main_ref_store(the_repository), NULL, item->string, NULL, REF_NO_DEREF))
-			die(_("deleting '%s' failed"), item->string);
-
-		strbuf_release(&referent);
-		display_progress(progress, ++refs_renamed_nr);
-	}
-	for (i = 0; i < remote_branches.nr; i++) {
-		struct string_list_item *item = remote_branches.items + i;
+	if (refspecs_need_update) {
+		result = ref_transaction_commit(rename.transaction, &err);
+		if (result < 0)
+			die(_("renaming remote refs failed: %s"), rename.err->buf);
 
-		if (item->util)
-			continue;
-		strbuf_reset(&buf);
-		strbuf_addstr(&buf, item->string);
-		strbuf_splice(&buf, strlen("refs/remotes/"), strlen(rename.old_name),
-				rename.new_name, strlen(rename.new_name));
-		strbuf_reset(&buf2);
-		strbuf_addf(&buf2, "remote: renamed %s to %s",
-				item->string, buf.buf);
-		if (refs_rename_ref(get_main_ref_store(the_repository), item->string, buf.buf, buf2.buf))
-			die(_("renaming '%s' failed"), item->string);
-		display_progress(progress, ++refs_renamed_nr);
-	}
-	for (i = 0; i < remote_branches.nr; i++) {
-		struct string_list_item *item = remote_branches.items + i;
+		stop_progress(&rename.progress);
 
-		if (!item->util)
-			continue;
-		strbuf_reset(&buf);
-		strbuf_addstr(&buf, item->string);
-		strbuf_splice(&buf, strlen("refs/remotes/"), strlen(rename.old_name),
-				rename.new_name, strlen(rename.new_name));
-		strbuf_reset(&buf2);
-		strbuf_addstr(&buf2, item->util);
-		strbuf_splice(&buf2, strlen("refs/remotes/"), strlen(rename.old_name),
-				rename.new_name, strlen(rename.new_name));
-		strbuf_reset(&buf3);
-		strbuf_addf(&buf3, "remote: renamed %s to %s",
-				item->string, buf.buf);
-		if (refs_update_symref(get_main_ref_store(the_repository), buf.buf, buf2.buf, buf3.buf))
-			die(_("creating '%s' failed"), buf.buf);
-		display_progress(progress, ++refs_renamed_nr);
+		handle_push_default(rename.old_name, rename.new_name);
 	}
-	stop_progress(&progress);
-
-	handle_push_default(rename.old_name, rename.new_name);
 
 out:
-	string_list_clear(&remote_branches, 1);
+	ref_transaction_free(rename.transaction);
 	strbuf_release(&old_remote_context);
 	strbuf_release(&buf);
 	strbuf_release(&buf2);
 	strbuf_release(&buf3);
+	strbuf_release(&err);
 	return result;
 }
 
@@ -920,7 +1014,7 @@ static int rm(int argc, const char **argv, const char *prefix,
 	struct string_list branches = STRING_LIST_INIT_DUP;
 	struct string_list skipped = STRING_LIST_INIT_DUP;
 	struct branches_for_remote cb_data;
-	int i, result;
+	int result;
 
 	memset(&cb_data, 0, sizeof(cb_data));
 	cb_data.branches = &branches;
@@ -942,7 +1036,7 @@ static int rm(int argc, const char **argv, const char *prefix,
 	for_each_remote(add_known_remote, &known_remotes);
 
 	read_branches();
-	for (i = 0; i < branch_list.nr; i++) {
+	for (size_t i = 0; i < branch_list.nr; i++) {
 		struct string_list_item *item = branch_list.items + i;
 		struct branch_info *info = item->util;
 		if (info->remote_name && !strcmp(info->remote_name, remote->name)) {
@@ -988,7 +1082,7 @@ static int rm(int argc, const char **argv, const char *prefix,
 			      "Note: Some branches outside the refs/remotes/ hierarchy were not removed;\n"
 			      "to delete them, use:",
 			      skipped.nr));
-		for (i = 0; i < skipped.nr; i++)
+		for (size_t i = 0; i < skipped.nr; i++)
 			fprintf(stderr, "  git branch -d %s\n",
 				skipped.items[i].string);
 	}
@@ -1166,7 +1260,6 @@ static int show_local_info_item(struct string_list_item *item, void *cb_data)
 	struct branch_info *branch_info = item->util;
 	struct string_list *merge = &branch_info->merge;
 	int width = show_info->width + 4;
-	int i;
 
 	if (branch_info->rebase >= REBASE_TRUE && branch_info->merge.nr > 1) {
 		error(_("invalid branch.%s.merge; cannot rebase onto > 1 branch"),
@@ -1192,7 +1285,7 @@ static int show_local_info_item(struct string_list_item *item, void *cb_data)
 	} else {
 		printf_ln(_("merges with remote %s"), merge->items[0].string);
 	}
-	for (i = 1; i < merge->nr; i++)
+	for (size_t i = 1; i < merge->nr; i++)
 		printf(_("%-*s    and with remote %s\n"), width, "",
 		       merge->items[i].string);
 
@@ -1277,7 +1370,6 @@ static int get_one_entry(struct remote *remote, void *priv)
 	struct string_list *list = priv;
 	struct strbuf remote_info_buf = STRBUF_INIT;
 	struct strvec *url;
-	int i;
 
 	if (remote->url.nr > 0) {
 		struct strbuf promisor_config = STRBUF_INIT;
@@ -1294,8 +1386,7 @@ static int get_one_entry(struct remote *remote, void *priv)
 	} else
 		string_list_append(list, remote->name)->util = NULL;
 	url = push_url_of_remote(remote);
-	for (i = 0; i < url->nr; i++)
-	{
+	for (size_t i = 0; i < url->nr; i++) {
 		strbuf_addf(&remote_info_buf, "%s (push)", url->v[i]);
 		string_list_append(list, remote->name)->util =
 				strbuf_detach(&remote_info_buf, NULL);
@@ -1312,10 +1403,8 @@ static int show_all(void)
 	result = for_each_remote(get_one_entry, &list);
 
 	if (!result) {
-		int i;
-
 		string_list_sort(&list);
-		for (i = 0; i < list.nr; i++) {
+		for (size_t i = 0; i < list.nr; i++) {
 			struct string_list_item *item = list.items + i;
 			if (verbose)
 				printf("%s\t%s\n", item->string,
@@ -1352,7 +1441,7 @@ static int show(int argc, const char **argv, const char *prefix,
 		query_flag = (GET_REF_STATES | GET_HEAD_NAMES | GET_PUSH_REF_STATES);
 
 	for (; argc; argc--, argv++) {
-		int i;
+		size_t i;
 		struct strvec *url;
 
 		get_remote_ref_states(*argv, &info.states, query_flag);
@@ -1458,7 +1547,7 @@ static void report_set_head_auto(const char *remote, const char *head_name,
 static int set_head(int argc, const char **argv, const char *prefix,
 		    struct repository *repo UNUSED)
 {
-	int i, opt_a = 0, opt_d = 0, result = 0, was_detached;
+	int opt_a = 0, opt_d = 0, result = 0, was_detached;
 	struct strbuf b_head = STRBUF_INIT, b_remote_head = STRBUF_INIT,
 		b_local_head = STRBUF_INIT;
 	char *head_name = NULL;
@@ -1492,7 +1581,7 @@ static int set_head(int argc, const char **argv, const char *prefix,
 		else if (states.heads.nr > 1) {
 			result |= error(_("Multiple remote HEAD branches. "
 					  "Please choose one explicitly with:"));
-			for (i = 0; i < states.heads.nr; i++)
+			for (size_t i = 0; i < states.heads.nr; i++)
 				fprintf(stderr, "  git remote set-head %s %s\n",
 					argv[0], states.heads.items[i].string);
 		} else
@@ -1717,7 +1806,7 @@ static int set_branches(int argc, const char **argv, const char *prefix,
 static int get_url(int argc, const char **argv, const char *prefix,
 		   struct repository *repo UNUSED)
 {
-	int i, push_mode = 0, all_mode = 0;
+	int push_mode = 0, all_mode = 0;
 	const char *remotename = NULL;
 	struct remote *remote;
 	struct strvec *url;
@@ -1745,7 +1834,7 @@ static int get_url(int argc, const char **argv, const char *prefix,
 	url = push_mode ? push_url_of_remote(remote) : &remote->url;
 
 	if (all_mode) {
-		for (i = 0; i < url->nr; i++)
+		for (size_t i = 0; i < url->nr; i++)
 			printf_ln("%s", url->v[i]);
 	} else {
 		printf_ln("%s", url->v[0]);
@@ -1757,7 +1846,7 @@ static int get_url(int argc, const char **argv, const char *prefix,
 static int set_url(int argc, const char **argv, const char *prefix,
 		   struct repository *repo UNUSED)
 {
-	int i, push_mode = 0, add_mode = 0, delete_mode = 0;
+	int push_mode = 0, add_mode = 0, delete_mode = 0;
 	int matches = 0, negative_matches = 0;
 	const char *remotename = NULL;
 	const char *newurl = NULL;
@@ -1821,7 +1910,7 @@ static int set_url(int argc, const char **argv, const char *prefix,
 	if (regcomp(&old_regex, oldurl, REG_EXTENDED))
 		die(_("Invalid old URL pattern: %s"), oldurl);
 
-	for (i = 0; i < urlset->nr; i++)
+	for (size_t i = 0; i < urlset->nr; i++)
 		if (!regexec(&old_regex, urlset->v[i], 0, NULL, 0))
 			matches++;
 		else
diff --git a/builtin/stash.c b/builtin/stash.c
index 1977e50df27fc5..f5ddee5c7fc556 100644
--- a/builtin/stash.c
+++ b/builtin/stash.c
@@ -738,7 +738,8 @@ static int apply_stash(int argc, const char **argv, const char *prefix,
 	return ret;
 }
 
-static int reject_reflog_ent(struct object_id *ooid UNUSED,
+static int reject_reflog_ent(const char *refname UNUSED,
+			     struct object_id *ooid UNUSED,
 			     struct object_id *noid UNUSED,
 			     const char *email UNUSED,
 			     timestamp_t timestamp UNUSED,
@@ -2207,7 +2208,8 @@ struct stash_entry_data {
 	size_t count;
 };
 
-static int collect_stash_entries(struct object_id *old_oid UNUSED,
+static int collect_stash_entries(const char *refname UNUSED,
+				 struct object_id *old_oid UNUSED,
 				 struct object_id *new_oid,
 				 const char *committer UNUSED,
 				 timestamp_t timestamp UNUSED,
diff --git a/builtin/var.c b/builtin/var.c
index a2d790d45320ae..cc3a43cde25a6c 100644
--- a/builtin/var.c
+++ b/builtin/var.c
@@ -182,7 +182,7 @@ static void list_vars(void)
 			if (ptr->multivalued && *val) {
 				struct string_list list = STRING_LIST_INIT_DUP;
 
-				string_list_split(&list, val, '\n', -1);
+				string_list_split(&list, val, "\n", -1);
 				for (size_t i = 0; i < list.nr; i++)
 					printf("%s=%s\n", ptr->name, list.items[i].string);
 				string_list_clear(&list, 0);
diff --git a/commit.c b/commit.c
index d1e1061214b9ab..16d91b2bfcf291 100644
--- a/commit.c
+++ b/commit.c
@@ -1039,7 +1039,8 @@ static void add_one_commit(struct object_id *oid, struct rev_collect *revs)
 	commit->object.flags |= TMP_MARK;
 }
 
-static int collect_one_reflog_ent(struct object_id *ooid, struct object_id *noid,
+static int collect_one_reflog_ent(const char *refname UNUSED,
+				  struct object_id *ooid, struct object_id *noid,
 				  const char *ident UNUSED,
 				  timestamp_t timestamp UNUSED, int tz UNUSED,
 				  const char *message UNUSED, void *cbdata)
diff --git a/config.c b/config.c
index 97ffef42700111..e0ff35d426648c 100644
--- a/config.c
+++ b/config.c
@@ -629,31 +629,28 @@ int git_config_parse_parameter(const char *text,
 			       config_fn_t fn, void *data)
 {
 	const char *value;
-	struct strbuf **pair;
+	struct string_list pair = STRING_LIST_INIT_DUP;
 	int ret;
 	struct key_value_info kvi = KVI_INIT;
 
 	kvi_from_param(&kvi);
 
-	pair = strbuf_split_str(text, '=', 2);
-	if (!pair[0])
+	string_list_split(&pair, text, "=", 1);
+	if (!pair.nr)
 		return error(_("bogus config parameter: %s"), text);
 
-	if (pair[0]->len && pair[0]->buf[pair[0]->len - 1] == '=') {
-		strbuf_setlen(pair[0], pair[0]->len - 1);
-		value = pair[1] ? pair[1]->buf : "";
-	} else {
+	if (pair.nr == 1)
 		value = NULL;
-	}
+	else
+		value = pair.items[1].string;
 
-	strbuf_trim(pair[0]);
-	if (!pair[0]->len) {
-		strbuf_list_free(pair);
+	if (!*pair.items[0].string) {
+		string_list_clear(&pair, 0);
 		return error(_("bogus config parameter: %s"), text);
 	}
 
-	ret = config_parse_pair(pair[0]->buf, value, &kvi, fn, data);
-	strbuf_list_free(pair);
+	ret = config_parse_pair(pair.items[0].string, value, &kvi, fn, data);
+	string_list_clear(&pair, 0);
 	return ret;
 }
 
diff --git a/connect.c b/connect.c
index 34cac24d54c638..8352b71faf0931 100644
--- a/connect.c
+++ b/connect.c
@@ -407,7 +407,7 @@ static int process_ref_v2(struct packet_reader *reader, struct ref ***list,
 	 * name.  Subsequent fields (symref-target and peeled) are optional and
 	 * don't have a particular order.
 	 */
-	if (string_list_split(&line_sections, line, ' ', -1) < 2) {
+	if (string_list_split(&line_sections, line, " ", -1) < 2) {
 		ret = 0;
 		goto out;
 	}
diff --git a/diff.c b/diff.c
index dca87e164fb615..70666ad2cd1ca6 100644
--- a/diff.c
+++ b/diff.c
@@ -327,29 +327,23 @@ static unsigned parse_color_moved_ws(const char *arg)
 	struct string_list l = STRING_LIST_INIT_DUP;
 	struct string_list_item *i;
 
-	string_list_split(&l, arg, ',', -1);
+	string_list_split_f(&l, arg, ",", -1, STRING_LIST_SPLIT_TRIM);
 
 	for_each_string_list_item(i, &l) {
-		struct strbuf sb = STRBUF_INIT;
-		strbuf_addstr(&sb, i->string);
-		strbuf_trim(&sb);
-
-		if (!strcmp(sb.buf, "no"))
+		if (!strcmp(i->string, "no"))
 			ret = 0;
-		else if (!strcmp(sb.buf, "ignore-space-change"))
+		else if (!strcmp(i->string, "ignore-space-change"))
 			ret |= XDF_IGNORE_WHITESPACE_CHANGE;
-		else if (!strcmp(sb.buf, "ignore-space-at-eol"))
+		else if (!strcmp(i->string, "ignore-space-at-eol"))
 			ret |= XDF_IGNORE_WHITESPACE_AT_EOL;
-		else if (!strcmp(sb.buf, "ignore-all-space"))
+		else if (!strcmp(i->string, "ignore-all-space"))
 			ret |= XDF_IGNORE_WHITESPACE;
-		else if (!strcmp(sb.buf, "allow-indentation-change"))
+		else if (!strcmp(i->string, "allow-indentation-change"))
 			ret |= COLOR_MOVED_WS_ALLOW_INDENTATION_CHANGE;
 		else {
 			ret |= COLOR_MOVED_WS_ERROR;
-			error(_("unknown color-moved-ws mode '%s', possible values are 'ignore-space-change', 'ignore-space-at-eol', 'ignore-all-space', 'allow-indentation-change'"), sb.buf);
+			error(_("unknown color-moved-ws mode '%s', possible values are 'ignore-space-change', 'ignore-space-at-eol', 'ignore-all-space', 'allow-indentation-change'"), i->string);
 		}
-
-		strbuf_release(&sb);
 	}
 
 	if ((ret & COLOR_MOVED_WS_ALLOW_INDENTATION_CHANGE) &&
diff --git a/environment.c b/environment.c
index ae1427bb9e8e62..59040e2d0f4aa5 100644
--- a/environment.c
+++ b/environment.c
@@ -175,10 +175,10 @@ int have_git_dir(void)
 const char *get_git_namespace(void)
 {
 	static const char *namespace;
-
 	struct strbuf buf = STRBUF_INIT;
-	struct strbuf **components, **c;
 	const char *raw_namespace;
+	struct string_list components = STRING_LIST_INIT_DUP;
+	struct string_list_item *item;
 
 	if (namespace)
 		return namespace;
@@ -190,12 +190,17 @@ const char *get_git_namespace(void)
 	}
 
 	strbuf_addstr(&buf, raw_namespace);
-	components = strbuf_split(&buf, '/');
+
+	string_list_split(&components, buf.buf, "/", -1);
 	strbuf_reset(&buf);
-	for (c = components; *c; c++)
-		if (strcmp((*c)->buf, "/") != 0)
-			strbuf_addf(&buf, "refs/namespaces/%s", (*c)->buf);
-	strbuf_list_free(components);
+
+	for_each_string_list_item(item, &components) {
+		if (item->string[0])
+			strbuf_addf(&buf, "refs/namespaces/%s/", item->string);
+	}
+	string_list_clear(&components, 0);
+
+	strbuf_trim_trailing_dir_sep(&buf);
 	if (check_refname_format(buf.buf, 0))
 		die(_("bad git namespace path \"%s\""), raw_namespace);
 	strbuf_addch(&buf, '/');
diff --git a/fetch-pack.c b/fetch-pack.c
index 46c39f85c4ca9e..20e5533b218542 100644
--- a/fetch-pack.c
+++ b/fetch-pack.c
@@ -1914,7 +1914,7 @@ static void fetch_pack_config(void)
 		char *str;
 
 		if (!repo_config_get_string(the_repository, "fetch.uriprotocols", &str) && str) {
-			string_list_split(&uri_protocols, str, ',', -1);
+			string_list_split(&uri_protocols, str, ",", -1);
 			free(str);
 		}
 	}
diff --git a/ident.c b/ident.c
index 281e830573b74d..0b7aacecd7d9af 100644
--- a/ident.c
+++ b/ident.c
@@ -272,7 +272,7 @@ static void strbuf_addstr_without_crud(struct strbuf *sb, const char *src)
  * can still be NULL if the input line only has the name/email part
  * (e.g. reading from a reflog entry).
  */
-int split_ident_line(struct ident_split *split, const char *line, int len)
+int split_ident_line(struct ident_split *split, const char *line, size_t len)
 {
 	const char *cp;
 	size_t span;
diff --git a/ident.h b/ident.h
index 6a79febba15fea..3c034038791b78 100644
--- a/ident.h
+++ b/ident.h
@@ -35,7 +35,7 @@ void reset_ident_date(void);
  * Signals an success with 0, but time part of the result may be NULL
  * if the input lacks timestamp and zone
  */
-int split_ident_line(struct ident_split *, const char *, int);
+int split_ident_line(struct ident_split *, const char *, size_t);
 
 /*
  * Given a commit or tag object buffer and the commit or tag headers, replaces
diff --git a/merge-ort.c b/merge-ort.c
index cd0cb4d1f07d2d..29858074f9d8bf 100644
--- a/merge-ort.c
+++ b/merge-ort.c
@@ -316,9 +316,14 @@ struct merge_options_internal {
 	 *     (e.g. "drivers/firmware/raspberrypi.c").
 	 *   * store all relevant paths in the repo, both directories and
 	 *     files (e.g. drivers, drivers/firmware would also be included)
-	 *   * these keys serve to intern all the path strings, which allows
-	 *     us to do pointer comparison on directory names instead of
-	 *     strcmp; we just have to be careful to use the interned strings.
+	 *   * these keys serve to intern *all* path strings, which allows us
+	 *     to do pointer comparisons on file & directory names instead of
+	 *     using strcmp; however, for this pointer-comparison optimization
+	 *     to work, any code path that independently computes a path needs
+	 *     to check for it existing in this strmap, and if so, point to
+	 *     the path in this strmap instead of their computed copy.  See
+	 *     the "reuse known pointer" comment in
+	 *     apply_directory_rename_modifications() for an example.
 	 *
 	 * The values of paths:
 	 *   * either a pointer to a merged_info, or a conflict_info struct
@@ -2163,7 +2168,7 @@ static int handle_content_merge(struct merge_options *opt,
 		/*
 		 * FIXME: If opt->priv->call_depth && !clean, then we really
 		 * should not make result->mode match either a->mode or
-		 * b->mode; that causes t6036 "check conflicting mode for
+		 * b->mode; that causes t6416 "check conflicting mode for
 		 * regular file" to fail.  It would be best to use some other
 		 * mode, but we'll confuse all kinds of stuff if we use one
 		 * where S_ISREG(result->mode) isn't true, and if we use
@@ -2313,14 +2318,20 @@ static char *apply_dir_rename(struct strmap_entry *rename_info,
 	return strbuf_detach(&new_path, NULL);
 }
 
-static int path_in_way(struct strmap *paths, const char *path, unsigned side_mask)
+static int path_in_way(struct strmap *paths,
+		       const char *path,
+		       unsigned side_mask,
+		       struct diff_filepair *p)
 {
 	struct merged_info *mi = strmap_get(paths, path);
 	struct conflict_info *ci;
 	if (!mi)
 		return 0;
 	INITIALIZE_CI(ci, mi);
-	return mi->clean || (side_mask & (ci->filemask | ci->dirmask));
+	return mi->clean || (side_mask & (ci->filemask | ci->dirmask))
+	  /* See testcases 12[npq] of t6423 for this next condition */
+			 || ((ci->filemask & 0x01) &&
+			     strcmp(p->one->path, path));
 }
 
 /*
@@ -2332,6 +2343,7 @@ static int path_in_way(struct strmap *paths, const char *path, unsigned side_mas
 static char *handle_path_level_conflicts(struct merge_options *opt,
 					 const char *path,
 					 unsigned side_index,
+					 struct diff_filepair *p,
 					 struct strmap_entry *rename_info,
 					 struct strmap *collisions)
 {
@@ -2366,7 +2378,7 @@ static char *handle_path_level_conflicts(struct merge_options *opt,
 	 */
 	if (c_info->reported_already) {
 		clean = 0;
-	} else if (path_in_way(&opt->priv->paths, new_path, 1 << side_index)) {
+	} else if (path_in_way(&opt->priv->paths, new_path, 1 << side_index, p)) {
 		c_info->reported_already = 1;
 		strbuf_add_separated_string_list(&collision_paths, ", ",
 						 &c_info->source_files);
@@ -2520,7 +2532,7 @@ static void compute_collisions(struct strmap *collisions,
 	 * happening, and fall back to no-directory-rename detection
 	 * behavior for those paths.
 	 *
-	 * See testcases 9e and all of section 5 from t6043 for examples.
+	 * See testcases 9e and all of section 5 from t6423 for examples.
 	 */
 	for (i = 0; i < pairs->nr; ++i) {
 		struct strmap_entry *rename_info;
@@ -2573,6 +2585,7 @@ static void free_collisions(struct strmap *collisions)
 static char *check_for_directory_rename(struct merge_options *opt,
 					const char *path,
 					unsigned side_index,
+					struct diff_filepair *p,
 					struct strmap *dir_renames,
 					struct strmap *dir_rename_exclusions,
 					struct strmap *collisions,
@@ -2580,7 +2593,6 @@ static char *check_for_directory_rename(struct merge_options *opt,
 {
 	char *new_path;
 	struct strmap_entry *rename_info;
-	struct strmap_entry *otherinfo;
 	const char *new_dir;
 	int other_side = 3 - side_index;
 
@@ -2615,14 +2627,13 @@ static char *check_for_directory_rename(struct merge_options *opt,
 	 * to not let Side1 do the rename to dumbdir, since we know that is
 	 * the source of one of our directory renames.
 	 *
-	 * That's why otherinfo and dir_rename_exclusions is here.
+	 * That's why dir_rename_exclusions is here.
 	 *
 	 * As it turns out, this also prevents N-way transient rename
-	 * confusion; See testcases 9c and 9d of t6043.
+	 * confusion; See testcases 9c and 9d of t6423.
 	 */
 	new_dir = rename_info->value; /* old_dir = rename_info->key; */
-	otherinfo = strmap_get_entry(dir_rename_exclusions, new_dir);
-	if (otherinfo) {
+	if (strmap_contains(dir_rename_exclusions, new_dir)) {
 		path_msg(opt, INFO_DIR_RENAME_SKIPPED_DUE_TO_RERENAME, 1,
 			 rename_info->key, path, new_dir, NULL,
 			 _("WARNING: Avoiding applying %s -> %s rename "
@@ -2631,7 +2642,7 @@ static char *check_for_directory_rename(struct merge_options *opt,
 		return NULL;
 	}
 
-	new_path = handle_path_level_conflicts(opt, path, side_index,
+	new_path = handle_path_level_conflicts(opt, path, side_index, p,
 					       rename_info,
 					       &collisions[side_index]);
 	*clean_merge &= (new_path != NULL);
@@ -2875,6 +2886,20 @@ static int process_renames(struct merge_options *opt,
 			newinfo = new_ent->value;
 		}
 
+		/*
+		 * Directory renames can result in rename-to-self; the code
+		 * below assumes we have A->B with different A & B, and tries
+		 * to move all entries to path B.  If A & B are the same path,
+		 * the logic can get confused, so skip further processing when
+		 * A & B are already the same path.
+		 *
+		 * As a reminder, we can avoid strcmp here because all paths
+		 * are interned in opt->priv->paths; see the comment above
+		 * "paths" in struct merge_options_internal.
+		 */
+		if (oldpath == newpath)
+			continue;
+
 		/*
 		 * If pair->one->path isn't in opt->priv->paths, that means
 		 * that either directory rename detection removed that
@@ -3419,7 +3444,7 @@ static int collect_renames(struct merge_options *opt,
 		}
 
 		new_path = check_for_directory_rename(opt, p->two->path,
-						      side_index,
+						      side_index, p,
 						      dir_renames_for_side,
 						      rename_exclusions,
 						      collisions,
diff --git a/notes.c b/notes.c
index 9736276f376a20..9a2e9181fe67d8 100644
--- a/notes.c
+++ b/notes.c
@@ -894,7 +894,7 @@ static int string_list_add_note_lines(struct string_list *list,
 	 * later, along with any empty strings that came from empty
 	 * lines within the file.
 	 */
-	string_list_split(list, data, '\n', -1);
+	string_list_split(list, data, "\n", -1);
 	free(data);
 	return 0;
 }
@@ -973,8 +973,8 @@ void string_list_add_refs_from_colon_sep(struct string_list *list,
 	char *globs_copy = xstrdup(globs);
 	int i;
 
-	string_list_split_in_place(&split, globs_copy, ":", -1);
-	string_list_remove_empty_items(&split, 0);
+	string_list_split_in_place_f(&split, globs_copy, ":", -1,
+				     STRING_LIST_SPLIT_NONEMPTY);
 
 	for (i = 0; i < split.nr; i++)
 		string_list_add_refs_by_glob(list, split.items[i].string);
diff --git a/object-name.c b/object-name.c
index 11aa0e6afc565e..732056ff5e305b 100644
--- a/object-name.c
+++ b/object-name.c
@@ -1525,7 +1525,8 @@ struct grab_nth_branch_switch_cbdata {
 	struct strbuf *sb;
 };
 
-static int grab_nth_branch_switch(struct object_id *ooid UNUSED,
+static int grab_nth_branch_switch(const char *refname UNUSED,
+				  struct object_id *ooid UNUSED,
 				  struct object_id *noid UNUSED,
 				  const char *email UNUSED,
 				  timestamp_t timestamp UNUSED,
diff --git a/parse-options.c b/parse-options.c
index 5224203ffe7bf8..9e7cb7519276c0 100644
--- a/parse-options.c
+++ b/parse-options.c
@@ -1338,7 +1338,7 @@ static enum parse_opt_result usage_with_options_internal(struct parse_opt_ctx_t
 		if (!saw_empty_line && !*str)
 			saw_empty_line = 1;
 
-		string_list_split(&list, str, '\n', -1);
+		string_list_split(&list, str, "\n", -1);
 		for (j = 0; j < list.nr; j++) {
 			const char *line = list.items[j].string;
 
diff --git a/pathspec.c b/pathspec.c
index a3ddd701c740c9..5993c4afa0eb37 100644
--- a/pathspec.c
+++ b/pathspec.c
@@ -201,8 +201,7 @@ static void parse_pathspec_attr_match(struct pathspec_item *item, const char *va
 	if (!value || !*value)
 		die(_("attr spec must not be empty"));
 
-	string_list_split(&list, value, ' ', -1);
-	string_list_remove_empty_items(&list, 0);
+	string_list_split_f(&list, value, " ", -1, STRING_LIST_SPLIT_NONEMPTY);
 
 	item->attr_check = attr_check_alloc();
 	CALLOC_ARRAY(item->attr_match, list.nr);
diff --git a/protocol.c b/protocol.c
index 65f66217021609..a3e26a8dd333b9 100644
--- a/protocol.c
+++ b/protocol.c
@@ -61,7 +61,7 @@ enum protocol_version determine_protocol_version_server(void)
 	if (git_protocol) {
 		struct string_list list = STRING_LIST_INIT_DUP;
 		const struct string_list_item *item;
-		string_list_split(&list, git_protocol, ':', -1);
+		string_list_split(&list, git_protocol, ":", -1);
 
 		for_each_string_list_item(item, &list) {
 			const char *value;
diff --git a/ref-filter.c b/ref-filter.c
index 4edf0df4cc2432..520d2539c9e163 100644
--- a/ref-filter.c
+++ b/ref-filter.c
@@ -435,7 +435,7 @@ static int remote_ref_atom_parser(struct ref_format *format UNUSED,
 	}
 
 	atom->u.remote_ref.nobracket = 0;
-	string_list_split(&params, arg, ',', -1);
+	string_list_split(&params, arg, ",", -1);
 
 	for (i = 0; i < params.nr; i++) {
 		const char *s = params.items[i].string;
@@ -831,7 +831,7 @@ static int align_atom_parser(struct ref_format *format UNUSED,
 
 	align->position = ALIGN_LEFT;
 
-	string_list_split(&params, arg, ',', -1);
+	string_list_split(&params, arg, ",", -1);
 	for (i = 0; i < params.nr; i++) {
 		const char *s = params.items[i].string;
 		int position;
diff --git a/reflog-walk.c b/reflog-walk.c
index c7070b13b004b7..4f1ce047498116 100644
--- a/reflog-walk.c
+++ b/reflog-walk.c
@@ -22,9 +22,10 @@ struct complete_reflogs {
 	int nr, alloc;
 };
 
-static int read_one_reflog(struct object_id *ooid, struct object_id *noid,
-		const char *email, timestamp_t timestamp, int tz,
-		const char *message, void *cb_data)
+static int read_one_reflog(const char *refname UNUSED,
+			   struct object_id *ooid, struct object_id *noid,
+			   const char *email, timestamp_t timestamp, int tz,
+			   const char *message, void *cb_data)
 {
 	struct complete_reflogs *array = cb_data;
 	struct reflog_info *item;
diff --git a/reflog.c b/reflog.c
index b267369f13e9e0..65ef259b4f5e1e 100644
--- a/reflog.c
+++ b/reflog.c
@@ -507,7 +507,8 @@ void reflog_expiry_cleanup(void *cb_data)
 	free_commit_list(cb->mark_list);
 }
 
-int count_reflog_ent(struct object_id *ooid UNUSED,
+int count_reflog_ent(const char *refname UNUSED,
+		     struct object_id *ooid UNUSED,
 		     struct object_id *noid UNUSED,
 		     const char *email UNUSED,
 		     timestamp_t timestamp, int tz UNUSED,
diff --git a/reflog.h b/reflog.h
index 74b3f3c4f0acf2..b996712c00f65e 100644
--- a/reflog.h
+++ b/reflog.h
@@ -65,7 +65,8 @@ void reflog_expiry_prepare(const char *refname, const struct object_id *oid,
 int should_expire_reflog_ent(struct object_id *ooid, struct object_id *noid,
 			     const char *email, timestamp_t timestamp, int tz,
 			     const char *message, void *cb_data);
-int count_reflog_ent(struct object_id *ooid, struct object_id *noid,
+int count_reflog_ent(const char *refname,
+		     struct object_id *ooid, struct object_id *noid,
 		     const char *email, timestamp_t timestamp, int tz,
 		     const char *message, void *cb_data);
 int should_expire_reflog_ent_verbose(struct object_id *ooid,
diff --git a/refs.c b/refs.c
index bfdbe718b70a38..4ff55cf24f68ee 100644
--- a/refs.c
+++ b/refs.c
@@ -1022,7 +1022,6 @@ int is_branch(const char *refname)
 }
 
 struct read_ref_at_cb {
-	const char *refname;
 	timestamp_t at_time;
 	int cnt;
 	int reccnt;
@@ -1052,7 +1051,8 @@ static void set_read_ref_cutoffs(struct read_ref_at_cb *cb,
 		*cb->cutoff_cnt = cb->reccnt;
 }
 
-static int read_ref_at_ent(struct object_id *ooid, struct object_id *noid,
+static int read_ref_at_ent(const char *refname,
+			   struct object_id *ooid, struct object_id *noid,
 			   const char *email UNUSED,
 			   timestamp_t timestamp, int tz,
 			   const char *message, void *cb_data)
@@ -1072,14 +1072,13 @@ static int read_ref_at_ent(struct object_id *ooid, struct object_id *noid,
 			oidcpy(cb->oid, noid);
 			if (!oideq(&cb->ooid, noid))
 				warning(_("log for ref %s has gap after %s"),
-					cb->refname, show_date(cb->date, cb->tz, DATE_MODE(RFC2822)));
+					refname, show_date(cb->date, cb->tz, DATE_MODE(RFC2822)));
 		}
 		else if (cb->date == cb->at_time)
 			oidcpy(cb->oid, noid);
 		else if (!oideq(noid, cb->oid))
 			warning(_("log for ref %s unexpectedly ended on %s"),
-				cb->refname, show_date(cb->date, cb->tz,
-						       DATE_MODE(RFC2822)));
+				refname, show_date(cb->date, cb->tz, DATE_MODE(RFC2822)));
 		cb->reccnt++;
 		oidcpy(&cb->ooid, ooid);
 		oidcpy(&cb->noid, noid);
@@ -1094,7 +1093,8 @@ static int read_ref_at_ent(struct object_id *ooid, struct object_id *noid,
 	return 0;
 }
 
-static int read_ref_at_ent_oldest(struct object_id *ooid, struct object_id *noid,
+static int read_ref_at_ent_oldest(const char *refname UNUSED,
+				  struct object_id *ooid, struct object_id *noid,
 				  const char *email UNUSED,
 				  timestamp_t timestamp, int tz,
 				  const char *message, void *cb_data)
@@ -1117,7 +1117,6 @@ int read_ref_at(struct ref_store *refs, const char *refname,
 	struct read_ref_at_cb cb;
 
 	memset(&cb, 0, sizeof(cb));
-	cb.refname = refname;
 	cb.at_time = at_time;
 	cb.cnt = cnt;
 	cb.msg = msg;
@@ -1362,27 +1361,22 @@ int ref_transaction_update(struct ref_transaction *transaction,
 	return 0;
 }
 
-/*
- * Similar to`ref_transaction_update`, but this function is only for adding
- * a reflog update. Supports providing custom committer information. The index
- * field can be utiltized to order updates as desired. When not used, the
- * updates default to being ordered by refname.
- */
-static int ref_transaction_update_reflog(struct ref_transaction *transaction,
-					 const char *refname,
-					 const struct object_id *new_oid,
-					 const struct object_id *old_oid,
-					 const char *committer_info,
-					 unsigned int flags,
-					 const char *msg,
-					 uint64_t index,
-					 struct strbuf *err)
+int ref_transaction_update_reflog(struct ref_transaction *transaction,
+				  const char *refname,
+				  const struct object_id *new_oid,
+				  const struct object_id *old_oid,
+				  const char *committer_info,
+				  const char *msg,
+				  uint64_t index,
+				  struct strbuf *err)
 {
 	struct ref_update *update;
+	unsigned int flags;
 
 	assert(err);
 
-	flags |= REF_LOG_ONLY | REF_FORCE_CREATE_REFLOG | REF_NO_DEREF;
+	flags = REF_HAVE_OLD | REF_HAVE_NEW | REF_LOG_ONLY | REF_FORCE_CREATE_REFLOG | REF_NO_DEREF |
+		REF_LOG_USE_PROVIDED_OIDS;
 
 	if (!transaction_refname_valid(refname, new_oid, flags, err))
 		return -1;
@@ -1390,11 +1384,6 @@ static int ref_transaction_update_reflog(struct ref_transaction *transaction,
 	update = ref_transaction_add_update(transaction, refname, flags,
 					    new_oid, old_oid, NULL, NULL,
 					    committer_info, msg);
-	/*
-	 * While we do set the old_oid value, we unset the flag to skip
-	 * old_oid verification which only makes sense for refs.
-	 */
-	update->flags &= ~REF_HAVE_OLD;
 	update->index = index;
 
 	/*
@@ -1850,7 +1839,13 @@ int refs_for_each_namespaced_ref(struct ref_store *refs,
 
 int refs_for_each_rawref(struct ref_store *refs, each_ref_fn fn, void *cb_data)
 {
-	return do_for_each_ref(refs, "", NULL, fn, 0,
+	return refs_for_each_rawref_in(refs, "", fn, cb_data);
+}
+
+int refs_for_each_rawref_in(struct ref_store *refs, const char *prefix,
+			    each_ref_fn fn, void *cb_data)
+{
+	return do_for_each_ref(refs, prefix, NULL, fn, 0,
 			       DO_FOR_EACH_INCLUDE_BROKEN, cb_data);
 }
 
@@ -2951,7 +2946,8 @@ struct migration_data {
 	struct ref_store *old_refs;
 	struct ref_transaction *transaction;
 	struct strbuf *errbuf;
-	struct strbuf sb;
+	struct strbuf sb, name, mail;
+	uint64_t index;
 };
 
 static int migrate_one_ref(const char *refname, const char *referent UNUSED, const struct object_id *oid,
@@ -2984,50 +2980,41 @@ static int migrate_one_ref(const char *refname, const char *referent UNUSED, con
 	return ret;
 }
 
-struct reflog_migration_data {
-	uint64_t index;
-	const char *refname;
-	struct ref_store *old_refs;
-	struct ref_transaction *transaction;
-	struct strbuf *errbuf;
-	struct strbuf *sb;
-};
-
-static int migrate_one_reflog_entry(struct object_id *old_oid,
+static int migrate_one_reflog_entry(const char *refname,
+				    struct object_id *old_oid,
 				    struct object_id *new_oid,
 				    const char *committer,
 				    timestamp_t timestamp, int tz,
 				    const char *msg, void *cb_data)
 {
-	struct reflog_migration_data *data = cb_data;
+	struct migration_data *data = cb_data;
+	struct ident_split ident;
 	const char *date;
 	int ret;
 
+	if (split_ident_line(&ident, committer, strlen(committer)) < 0)
+		return -1;
+
+	strbuf_reset(&data->name);
+	strbuf_add(&data->name, ident.name_begin, ident.name_end - ident.name_begin);
+	strbuf_reset(&data->mail);
+	strbuf_add(&data->mail, ident.mail_begin, ident.mail_end - ident.mail_begin);
+
 	date = show_date(timestamp, tz, DATE_MODE(NORMAL));
-	strbuf_reset(data->sb);
-	/* committer contains name and email */
-	strbuf_addstr(data->sb, fmt_ident("", committer, WANT_BLANK_IDENT, date, 0));
-
-	ret = ref_transaction_update_reflog(data->transaction, data->refname,
-					    new_oid, old_oid, data->sb->buf,
-					    REF_HAVE_NEW | REF_HAVE_OLD, msg,
-					    data->index++, data->errbuf);
+	strbuf_reset(&data->sb);
+	strbuf_addstr(&data->sb, fmt_ident(data->name.buf, data->mail.buf, WANT_BLANK_IDENT, date, 0));
+
+	ret = ref_transaction_update_reflog(data->transaction, refname,
+					    new_oid, old_oid, data->sb.buf,
+					    msg, data->index++, data->errbuf);
 	return ret;
 }
 
 static int migrate_one_reflog(const char *refname, void *cb_data)
 {
 	struct migration_data *migration_data = cb_data;
-	struct reflog_migration_data data = {
-		.refname = refname,
-		.old_refs = migration_data->old_refs,
-		.transaction = migration_data->transaction,
-		.errbuf = migration_data->errbuf,
-		.sb = &migration_data->sb,
-	};
-
 	return refs_for_each_reflog_ent(migration_data->old_refs, refname,
-					migrate_one_reflog_entry, &data);
+					migrate_one_reflog_entry, migration_data);
 }
 
 static int move_files(const char *from_path, const char *to_path, struct strbuf *errbuf)
@@ -3122,6 +3109,8 @@ int repo_migrate_ref_storage_format(struct repository *repo,
 	struct strbuf new_gitdir = STRBUF_INIT;
 	struct migration_data data = {
 		.sb = STRBUF_INIT,
+		.name = STRBUF_INIT,
+		.mail = STRBUF_INIT,
 	};
 	int did_migrate_refs = 0;
 	int ret;
@@ -3297,11 +3286,16 @@ int repo_migrate_ref_storage_format(struct repository *repo,
 	ref_transaction_free(transaction);
 	strbuf_release(&new_gitdir);
 	strbuf_release(&data.sb);
+	strbuf_release(&data.name);
+	strbuf_release(&data.mail);
 	return ret;
 }
 
 int ref_update_expects_existing_old_ref(struct ref_update *update)
 {
+	if (update->flags & REF_LOG_ONLY)
+		return 0;
+
 	return (update->flags & REF_HAVE_OLD) &&
 		(!is_null_oid(&update->old_oid) || update->old_target);
 }
diff --git a/refs.h b/refs.h
index eedbb599c52aac..f29e486e332f6d 100644
--- a/refs.h
+++ b/refs.h
@@ -428,6 +428,8 @@ int refs_for_each_namespaced_ref(struct ref_store *refs,
 
 /* can be used to learn about broken ref and symref */
 int refs_for_each_rawref(struct ref_store *refs, each_ref_fn fn, void *cb_data);
+int refs_for_each_rawref_in(struct ref_store *refs, const char *prefix,
+			    each_ref_fn fn, void *cb_data);
 
 /*
  * Iterates over all refs including root refs, i.e. pseudorefs and HEAD.
@@ -558,10 +560,13 @@ int refs_delete_reflog(struct ref_store *refs, const char *refname);
  * The cb_data is a caller-supplied pointer given to the iterator
  * functions.
  */
-typedef int each_reflog_ent_fn(
-		struct object_id *old_oid, struct object_id *new_oid,
-		const char *committer, timestamp_t timestamp,
-		int tz, const char *msg, void *cb_data);
+typedef int each_reflog_ent_fn(const char *refname,
+			       struct object_id *old_oid,
+			       struct object_id *new_oid,
+			       const char *committer,
+			       timestamp_t timestamp,
+			       int tz, const char *msg,
+			       void *cb_data);
 
 /* Iterate over reflog entries in the log for `refname`. */
 
@@ -759,13 +764,20 @@ struct ref_transaction *ref_store_transaction_begin(struct ref_store *refs,
  */
 #define REF_SKIP_CREATE_REFLOG (1 << 12)
 
+/*
+ * When writing a REF_LOG_ONLY record, use the old and new object IDs provided
+ * in the update instead of resolving the old object ID. The caller must also
+ * set both REF_HAVE_OLD and REF_HAVE_NEW.
+ */
+#define REF_LOG_USE_PROVIDED_OIDS (1 << 13)
+
 /*
  * Bitmask of all of the flags that are allowed to be passed in to
  * ref_transaction_update() and friends:
  */
 #define REF_TRANSACTION_UPDATE_ALLOWED_FLAGS                                  \
 	(REF_NO_DEREF | REF_FORCE_CREATE_REFLOG | REF_SKIP_OID_VERIFICATION | \
-	 REF_SKIP_REFNAME_VERIFICATION | REF_SKIP_CREATE_REFLOG)
+	 REF_SKIP_REFNAME_VERIFICATION | REF_SKIP_CREATE_REFLOG | REF_LOG_USE_PROVIDED_OIDS)
 
 /*
  * Add a reference update to transaction. `new_oid` is the value that
@@ -794,6 +806,21 @@ int ref_transaction_update(struct ref_transaction *transaction,
 			   unsigned int flags, const char *msg,
 			   struct strbuf *err);
 
+/*
+ * Similar to `ref_transaction_update`, but this function is only for adding
+ * a reflog update. Supports providing custom committer information. The index
+ * field can be utiltized to order updates as desired. When set to zero, the
+ * updates default to being ordered by refname.
+ */
+int ref_transaction_update_reflog(struct ref_transaction *transaction,
+				  const char *refname,
+				  const struct object_id *new_oid,
+				  const struct object_id *old_oid,
+				  const char *committer_info,
+				  const char *msg,
+				  uint64_t index,
+				  struct strbuf *err);
+
 /*
  * Add a reference creation to transaction. new_oid is the value that
  * the reference should have after the update; it must not be
diff --git a/refs/debug.c b/refs/debug.c
index da300efaf30973..1cb955961ee37b 100644
--- a/refs/debug.c
+++ b/refs/debug.c
@@ -277,7 +277,8 @@ struct debug_reflog {
 	void *cb_data;
 };
 
-static int debug_print_reflog_ent(struct object_id *old_oid,
+static int debug_print_reflog_ent(const char *refname,
+				  struct object_id *old_oid,
 				  struct object_id *new_oid,
 				  const char *committer, timestamp_t timestamp,
 				  int tz, const char *msg, void *cb_data)
@@ -292,7 +293,7 @@ static int debug_print_reflog_ent(struct object_id *old_oid,
 	if (new_oid)
 		oid_to_hex_r(n, new_oid);
 
-	ret = dbg->fn(old_oid, new_oid, committer, timestamp, tz, msg,
+	ret = dbg->fn(refname, old_oid, new_oid, committer, timestamp, tz, msg,
 		      dbg->cb_data);
 	trace_printf_key(&trace_refs,
 			 "reflog_ent %s (ret %d): %s -> %s, %s %ld \"%.*s\"\n",
diff --git a/refs/files-backend.c b/refs/files-backend.c
index 088b52c740b9ff..dfc8e9bc5055ab 100644
--- a/refs/files-backend.c
+++ b/refs/files-backend.c
@@ -68,6 +68,12 @@
  */
 #define REF_DELETED_RMDIR (1 << 9)
 
+/*
+ * Used to indicate that the reflog-only update has been created via
+ * `split_head_update()`.
+ */
+#define REF_LOG_VIA_SPLIT (1 << 14)
+
 struct ref_lock {
 	char *ref_name;
 	struct lock_file lk;
@@ -2109,7 +2115,9 @@ static int files_delete_reflog(struct ref_store *ref_store,
 	return ret;
 }
 
-static int show_one_reflog_ent(struct files_ref_store *refs, struct strbuf *sb,
+static int show_one_reflog_ent(struct files_ref_store *refs,
+			       const char *refname,
+			       struct strbuf *sb,
 			       each_reflog_ent_fn fn, void *cb_data)
 {
 	struct object_id ooid, noid;
@@ -2136,7 +2144,7 @@ static int show_one_reflog_ent(struct files_ref_store *refs, struct strbuf *sb,
 		message += 6;
 	else
 		message += 7;
-	return fn(&ooid, &noid, p, timestamp, tz, message, cb_data);
+	return fn(refname, &ooid, &noid, p, timestamp, tz, message, cb_data);
 }
 
 static char *find_beginning_of_line(char *bob, char *scan)
@@ -2220,7 +2228,7 @@ static int files_for_each_reflog_ent_reverse(struct ref_store *ref_store,
 				strbuf_splice(&sb, 0, 0, bp + 1, endp - (bp + 1));
 				scanp = bp;
 				endp = bp + 1;
-				ret = show_one_reflog_ent(refs, &sb, fn, cb_data);
+				ret = show_one_reflog_ent(refs, refname, &sb, fn, cb_data);
 				strbuf_reset(&sb);
 				if (ret)
 					break;
@@ -2232,7 +2240,7 @@ static int files_for_each_reflog_ent_reverse(struct ref_store *ref_store,
 				 * Process it, and we can end the loop.
 				 */
 				strbuf_splice(&sb, 0, 0, buf, endp - buf);
-				ret = show_one_reflog_ent(refs, &sb, fn, cb_data);
+				ret = show_one_reflog_ent(refs, refname, &sb, fn, cb_data);
 				strbuf_reset(&sb);
 				break;
 			}
@@ -2282,7 +2290,7 @@ static int files_for_each_reflog_ent(struct ref_store *ref_store,
 		return -1;
 
 	while (!ret && !strbuf_getwholeline(&sb, logfp, '\n'))
-		ret = show_one_reflog_ent(refs, &sb, fn, cb_data);
+		ret = show_one_reflog_ent(refs, refname, &sb, fn, cb_data);
 	fclose(logfp);
 	strbuf_release(&sb);
 	return ret;
@@ -2421,9 +2429,10 @@ static enum ref_transaction_error split_head_update(struct ref_update *update,
 
 	new_update = ref_transaction_add_update(
 			transaction, "HEAD",
-			update->flags | REF_LOG_ONLY | REF_NO_DEREF,
+			update->flags | REF_LOG_ONLY | REF_NO_DEREF | REF_LOG_VIA_SPLIT,
 			&update->new_oid, &update->old_oid,
 			NULL, NULL, update->committer_info, update->msg);
+	new_update->parent_update = update;
 
 	/*
 	 * Add "HEAD". This insertion is O(N) in the transaction
@@ -2494,7 +2503,6 @@ static enum ref_transaction_error split_symref_update(struct ref_update *update,
 	 * done when new_update is processed.
 	 */
 	update->flags |= REF_LOG_ONLY | REF_NO_DEREF;
-	update->flags &= ~REF_HAVE_OLD;
 
 	return 0;
 }
@@ -2509,8 +2517,9 @@ static enum ref_transaction_error check_old_oid(struct ref_update *update,
 						struct object_id *oid,
 						struct strbuf *err)
 {
-	if (!(update->flags & REF_HAVE_OLD) ||
-		   oideq(oid, &update->old_oid))
+	if (update->flags & REF_LOG_ONLY ||
+	    !(update->flags & REF_HAVE_OLD) ||
+	    oideq(oid, &update->old_oid))
 		return 0;
 
 	if (is_null_oid(&update->old_oid)) {
@@ -2601,7 +2610,36 @@ static enum ref_transaction_error lock_ref_for_update(struct files_ref_store *re
 
 	update->backend_data = lock;
 
-	if (update->type & REF_ISSYMREF) {
+	if (update->flags & REF_LOG_VIA_SPLIT) {
+		struct ref_lock *parent_lock;
+
+		if (!update->parent_update)
+			BUG("split update without a parent");
+
+		parent_lock = update->parent_update->backend_data;
+
+		/*
+		 * Check that "HEAD" didn't racily change since we have looked
+		 * it up. If it did we must refuse to write the reflog entry.
+		 *
+		 * Note that this does not catch all races: if "HEAD" was
+		 * racily changed to point to one of the refs part of the
+		 * transaction then we would miss writing the split reflog
+		 * entry for "HEAD".
+		 */
+		if (!(update->type & REF_ISSYMREF) ||
+		    strcmp(update->parent_update->refname, referent.buf)) {
+			strbuf_addstr(err, "HEAD has been racily updated");
+			ret = REF_TRANSACTION_ERROR_GENERIC;
+			goto out;
+		}
+
+		if (update->flags & REF_HAVE_OLD) {
+			oidcpy(&lock->old_oid, &update->old_oid);
+		} else {
+			oidcpy(&lock->old_oid, &parent_lock->old_oid);
+		}
+	} else if (update->type & REF_ISSYMREF) {
 		if (update->flags & REF_NO_DEREF) {
 			/*
 			 * We won't be reading the referent as part of
@@ -2977,6 +3015,20 @@ static int parse_and_write_reflog(struct files_ref_store *refs,
 				  struct ref_lock *lock,
 				  struct strbuf *err)
 {
+	struct object_id *old_oid = &lock->old_oid;
+
+	if (update->flags & REF_LOG_USE_PROVIDED_OIDS) {
+		if (!(update->flags & REF_HAVE_OLD) ||
+		    !(update->flags & REF_HAVE_NEW) ||
+		    !(update->flags & REF_LOG_ONLY)) {
+			strbuf_addf(err, _("trying to write reflog for '%s'"
+					   "with incomplete values"), update->refname);
+			return REF_TRANSACTION_ERROR_GENERIC;
+		}
+
+		old_oid = &update->old_oid;
+	}
+
 	if (update->new_target) {
 		/*
 		 * We want to get the resolved OID for the target, to ensure
@@ -2994,7 +3046,7 @@ static int parse_and_write_reflog(struct files_ref_store *refs,
 		}
 	}
 
-	if (files_log_ref_write(refs, lock->ref_name, &lock->old_oid,
+	if (files_log_ref_write(refs, lock->ref_name, old_oid,
 				&update->new_oid, update->committer_info,
 				update->msg, update->flags, err)) {
 		char *old_msg = strbuf_detach(err, NULL);
@@ -3062,7 +3114,8 @@ static int files_transaction_finish_initial(struct files_ref_store *refs,
 	for (i = 0; i < transaction->nr; i++) {
 		struct ref_update *update = transaction->updates[i];
 
-		if ((update->flags & REF_HAVE_OLD) &&
+		if (!(update->flags & REF_LOG_ONLY) &&
+		    (update->flags & REF_HAVE_OLD) &&
 		    !is_null_oid(&update->old_oid))
 			BUG("initial ref transaction with old_sha1 set");
 
@@ -3309,7 +3362,8 @@ struct expire_reflog_cb {
 		     dry_run:1;
 };
 
-static int expire_reflog_ent(struct object_id *ooid, struct object_id *noid,
+static int expire_reflog_ent(const char *refname UNUSED,
+			     struct object_id *ooid, struct object_id *noid,
 			     const char *email, timestamp_t timestamp, int tz,
 			     const char *message, void *cb_data)
 {
diff --git a/refs/refs-internal.h b/refs/refs-internal.h
index 40c1c0f93dc8be..54c2079c1264e8 100644
--- a/refs/refs-internal.h
+++ b/refs/refs-internal.h
@@ -662,7 +662,8 @@ enum ref_transaction_error ref_update_check_old_target(const char *referent,
 
 /*
  * Check if the ref must exist, this means that the old_oid or
- * old_target is non NULL.
+ * old_target is non NULL. Log-only updates never require the old state to
+ * match.
  */
 int ref_update_expects_existing_old_ref(struct ref_update *update);
 
diff --git a/refs/reftable-backend.c b/refs/reftable-backend.c
index 8dae1e1112ccaf..570463da4173c7 100644
--- a/refs/reftable-backend.c
+++ b/refs/reftable-backend.c
@@ -1102,6 +1102,20 @@ static enum ref_transaction_error prepare_single_update(struct reftable_ref_stor
 	if (ret)
 		return REF_TRANSACTION_ERROR_GENERIC;
 
+	if (u->flags & REF_LOG_USE_PROVIDED_OIDS) {
+		if (!(u->flags & REF_HAVE_OLD) ||
+		    !(u->flags & REF_HAVE_NEW) ||
+		    !(u->flags & REF_LOG_ONLY)) {
+			strbuf_addf(err, _("trying to write reflog for '%s'"
+					   "with incomplete values"), u->refname);
+			return REF_TRANSACTION_ERROR_GENERIC;
+		}
+
+		if (queue_transaction_update(refs, tx_data, u, &u->old_oid, err))
+			return REF_TRANSACTION_ERROR_GENERIC;
+		return 0;
+	}
+
 	/* Verify that the new object ID is valid. */
 	if ((u->flags & REF_HAVE_NEW) && !is_null_oid(&u->new_oid) &&
 	    !(u->flags & REF_SKIP_OID_VERIFICATION) &&
@@ -1186,8 +1200,6 @@ static enum ref_transaction_error prepare_single_update(struct reftable_ref_stor
 	if (ret > 0) {
 		/* The reference does not exist, but we expected it to. */
 		strbuf_addf(err, _("cannot lock ref '%s': "
-
-
 				   "unable to resolve reference '%s'"),
 			    ref_update_original_update_refname(u), u->refname);
 		return REF_TRANSACTION_ERROR_NONEXISTENT_REF;
@@ -1241,13 +1253,8 @@ static enum ref_transaction_error prepare_single_update(struct reftable_ref_stor
 
 			new_update->parent_update = u;
 
-			/*
-			 * Change the symbolic ref update to log only. Also, it
-			 * doesn't need to check its old OID value, as that will be
-			 * done when new_update is processed.
-			 */
+			/* Change the symbolic ref update to log only. */
 			u->flags |= REF_LOG_ONLY | REF_NO_DEREF;
-			u->flags &= ~REF_HAVE_OLD;
 		}
 	}
 
@@ -1271,7 +1278,8 @@ static enum ref_transaction_error prepare_single_update(struct reftable_ref_stor
 		ret = ref_update_check_old_target(referent->buf, u, err);
 		if (ret)
 			return ret;
-	} else if ((u->flags & REF_HAVE_OLD) && !oideq(&current_oid, &u->old_oid)) {
+	} else if ((u->flags & (REF_LOG_ONLY | REF_HAVE_OLD)) == REF_HAVE_OLD &&
+		   !oideq(&current_oid, &u->old_oid)) {
 		if (is_null_oid(&u->old_oid)) {
 			strbuf_addf(err, _("cannot lock ref '%s': "
 					   "reference already exists"),
@@ -2147,7 +2155,7 @@ static int yield_log_record(struct reftable_ref_store *refs,
 
 	full_committer = fmt_ident(log->value.update.name, log->value.update.email,
 				   WANT_COMMITTER_IDENT, NULL, IDENT_NO_DATE);
-	return fn(&old_oid, &new_oid, full_committer,
+	return fn(log->refname, &old_oid, &new_oid, full_committer,
 		  log->value.update.time, log->value.update.tz_offset,
 		  log->value.update.message, cb_data);
 }
diff --git a/remote.c b/remote.c
index 88f991795b2683..81d8fc017e1b37 100644
--- a/remote.c
+++ b/remote.c
@@ -1171,7 +1171,6 @@ static void show_push_unqualified_ref_name_error(const char *dst_value,
 						 const char *matched_src_name)
 {
 	struct object_id oid;
-	enum object_type type;
 
 	/*
 	 * TRANSLATORS: "matches '%s'%" is the <dst> part of "git push
@@ -1196,30 +1195,37 @@ static void show_push_unqualified_ref_name_error(const char *dst_value,
 		BUG("'%s' is not a valid object, "
 		    "match_explicit_lhs() should catch this!",
 		    matched_src_name);
-	type = odb_read_object_info(the_repository->objects, &oid, NULL);
-	if (type == OBJ_COMMIT) {
+
+	switch (odb_read_object_info(the_repository->objects, &oid, NULL)) {
+	case OBJ_COMMIT:
 		advise(_("The <src> part of the refspec is a commit object.\n"
 			 "Did you mean to create a new branch by pushing to\n"
 			 "'%s:refs/heads/%s'?"),
 		       matched_src_name, dst_value);
-	} else if (type == OBJ_TAG) {
+		break;
+	case OBJ_TAG:
 		advise(_("The <src> part of the refspec is a tag object.\n"
 			 "Did you mean to create a new tag by pushing to\n"
 			 "'%s:refs/tags/%s'?"),
 		       matched_src_name, dst_value);
-	} else if (type == OBJ_TREE) {
+		break;
+	case OBJ_TREE:
 		advise(_("The <src> part of the refspec is a tree object.\n"
 			 "Did you mean to tag a new tree by pushing to\n"
 			 "'%s:refs/tags/%s'?"),
 		       matched_src_name, dst_value);
-	} else if (type == OBJ_BLOB) {
+		break;
+	case OBJ_BLOB:
 		advise(_("The <src> part of the refspec is a blob object.\n"
 			 "Did you mean to tag a new blob by pushing to\n"
 			 "'%s:refs/tags/%s'?"),
 		       matched_src_name, dst_value);
-	} else {
-		BUG("'%s' should be commit/tag/tree/blob, is '%d'",
-		    matched_src_name, type);
+		break;
+	default:
+		advise(_("The <src> part of the refspec ('%s') "
+			 "is an object ID that doesn't exist.\n"),
+		       matched_src_name);
+		break;
 	}
 }
 
@@ -2578,7 +2584,8 @@ struct check_and_collect_until_cb_data {
 };
 
 /* Get the timestamp of the latest entry. */
-static int peek_reflog(struct object_id *o_oid UNUSED,
+static int peek_reflog(const char *refname UNUSED,
+		       struct object_id *o_oid UNUSED,
 		       struct object_id *n_oid UNUSED,
 		       const char *ident UNUSED,
 		       timestamp_t timestamp, int tz UNUSED,
@@ -2589,7 +2596,8 @@ static int peek_reflog(struct object_id *o_oid UNUSED,
 	return 1;
 }
 
-static int check_and_collect_until(struct object_id *o_oid UNUSED,
+static int check_and_collect_until(const char *refname UNUSED,
+				   struct object_id *o_oid UNUSED,
 				   struct object_id *n_oid,
 				   const char *ident UNUSED,
 				   timestamp_t timestamp, int tz UNUSED,
diff --git a/revision.c b/revision.c
index 18f300d4555552..6ba8f670542ce3 100644
--- a/revision.c
+++ b/revision.c
@@ -671,12 +671,17 @@ static void trace2_bloom_filter_statistics_atexit(void)
 
 static int forbid_bloom_filters(struct pathspec *spec)
 {
-	if (spec->has_wildcard)
-		return 1;
-	if (spec->magic & ~PATHSPEC_LITERAL)
+	unsigned int allowed_magic =
+		PATHSPEC_FROMTOP |
+		PATHSPEC_MAXDEPTH |
+		PATHSPEC_LITERAL |
+		PATHSPEC_GLOB |
+		PATHSPEC_ATTR;
+
+	if (spec->magic & ~allowed_magic)
 		return 1;
 	for (size_t nr = 0; nr < spec->nr; nr++)
-		if (spec->items[nr].magic & ~PATHSPEC_LITERAL)
+		if (spec->items[nr].magic & ~allowed_magic)
 			return 1;
 
 	return 0;
@@ -691,23 +696,34 @@ static int convert_pathspec_to_bloom_keyvec(struct bloom_keyvec **out,
 	char *path_alloc = NULL;
 	const char *path;
 	size_t len;
-	int res = 0;
+	int res = -1;
 
+	len = pi->nowildcard_len;
+	if (len != pi->len) {
+		/*
+		 * for path like "dir/file*", nowildcard part would be
+		 * "dir/file", but only "dir" should be used for the
+		 * bloom filter.
+		 */
+		while (len > 0 && pi->match[len - 1] != '/')
+			len--;
+	}
 	/* remove single trailing slash from path, if needed */
-	if (pi->len > 0 && pi->match[pi->len - 1] == '/') {
-		path_alloc = xmemdupz(pi->match, pi->len - 1);
+	if (len > 0 && pi->match[len - 1] == '/')
+		len--;
+
+	if (!len)
+		goto cleanup;
+
+	if (len != pi->len) {
+		path_alloc = xmemdupz(pi->match, len);
 		path = path_alloc;
 	} else
 		path = pi->match;
 
-	len = strlen(path);
-	if (!len) {
-		res = -1;
-		goto cleanup;
-	}
-
 	*out = bloom_keyvec_new(path, len, settings);
 
+	res = 0;
 cleanup:
 	free(path_alloc);
 	return res;
@@ -1689,7 +1705,8 @@ static void handle_one_reflog_commit(struct object_id *oid, void *cb_data)
 	}
 }
 
-static int handle_one_reflog_ent(struct object_id *ooid, struct object_id *noid,
+static int handle_one_reflog_ent(const char *refname UNUSED,
+				 struct object_id *ooid, struct object_id *noid,
 				 const char *email UNUSED,
 				 timestamp_t timestamp UNUSED,
 				 int tz UNUSED,
diff --git a/sequencer.c b/sequencer.c
index aaf2e4df64ed0b..9ae40a91b24963 100644
--- a/sequencer.c
+++ b/sequencer.c
@@ -2721,6 +2721,7 @@ static int check_merge_commit_insn(enum todo_command command)
 		return error(_("cannot squash merge commit into another commit"));
 
 	case TODO_MERGE:
+	case TODO_DROP:
 		return 0;
 
 	default:
diff --git a/setup.c b/setup.c
index 98ddbf377f923b..7086741e6c2d1f 100644
--- a/setup.c
+++ b/setup.c
@@ -1460,8 +1460,9 @@ static enum discovery_result setup_git_directory_gently_1(struct strbuf *dir,
 
 	if (env_ceiling_dirs) {
 		int empty_entry_found = 0;
+		static const char path_sep[] = { PATH_SEP, '\0' };
 
-		string_list_split(&ceiling_dirs, env_ceiling_dirs, PATH_SEP, -1);
+		string_list_split(&ceiling_dirs, env_ceiling_dirs, path_sep, -1);
 		filter_string_list(&ceiling_dirs, 0,
 				   canonicalize_ceiling_entry, &empty_entry_found);
 		ceil_offset = longest_ancestor_length(dir->buf, &ceiling_dirs);
diff --git a/string-list.c b/string-list.c
index 53faaa84207bf9..343cf1ca90d2ac 100644
--- a/string-list.c
+++ b/string-list.c
@@ -276,55 +276,99 @@ void unsorted_string_list_delete_item(struct string_list *list, int i, int free_
 	list->nr--;
 }
 
-int string_list_split(struct string_list *list, const char *string,
-		      int delim, int maxsplit)
+/*
+ * append a substring [p..end] to list; return number of things it
+ * appended to the list.
+ */
+static int append_one(struct string_list *list,
+		      const char *p, const char *end,
+		      int in_place, unsigned flags)
+{
+	if (!end)
+		end = p + strlen(p);
+
+	if ((flags & STRING_LIST_SPLIT_TRIM)) {
+		/* rtrim */
+		for (; p < end; end--)
+			if (!isspace(end[-1]))
+				break;
+	}
+
+	if ((flags & STRING_LIST_SPLIT_NONEMPTY) && (end <= p))
+		return 0;
+
+	if (in_place) {
+		*((char *)end) = '\0';
+		string_list_append(list, p);
+	} else {
+		string_list_append_nodup(list, xmemdupz(p, end - p));
+	}
+	return 1;
+}
+
+/*
+ * Unfortunately this cannot become a public interface, as _in_place()
+ * wants to have "const char *string" while the other variant wants to
+ * have "char *string" for type safety.
+ *
+ * This accepts "const char *string" to allow both wrappers to use it;
+ * it internally casts away the constness when in_place is true by
+ * taking advantage of strpbrk() that takes a "const char *" arg and
+ * returns "char *" pointer into that const string.  Yucky but works ;-).
+ */
+static int split_string(struct string_list *list, const char *string, const char *delim,
+			int maxsplit, int in_place, unsigned flags)
 {
 	int count = 0;
-	const char *p = string, *end;
+	const char *p = string;
+
+	if (in_place && list->strdup_strings)
+		BUG("string_list_split_in_place() called with strdup_strings");
+	else if (!in_place && !list->strdup_strings)
+		BUG("string_list_split() called without strdup_strings");
 
-	if (!list->strdup_strings)
-		die("internal error in string_list_split(): "
-		    "list->strdup_strings must be set");
 	for (;;) {
-		count++;
-		if (maxsplit >= 0 && count > maxsplit) {
-			string_list_append(list, p);
-			return count;
+		char *end;
+
+		if (flags & STRING_LIST_SPLIT_TRIM) {
+			/* ltrim */
+			while (*p && isspace(*p))
+				p++;
 		}
-		end = strchr(p, delim);
-		if (end) {
-			string_list_append_nodup(list, xmemdupz(p, end - p));
-			p = end + 1;
-		} else {
-			string_list_append(list, p);
+
+		if (0 <= maxsplit && maxsplit <= count)
+			end = NULL;
+		else
+			end = strpbrk(p, delim);
+
+		count += append_one(list, p, end, in_place, flags);
+
+		if (!end)
 			return count;
-		}
+		p = end + 1;
 	}
 }
 
+int string_list_split(struct string_list *list, const char *string,
+		      const char *delim, int maxsplit)
+{
+	return split_string(list, string, delim, maxsplit, 0, 0);
+}
+
 int string_list_split_in_place(struct string_list *list, char *string,
 			       const char *delim, int maxsplit)
 {
-	int count = 0;
-	char *p = string, *end;
+	return split_string(list, string, delim, maxsplit, 1, 0);
+}
 
-	if (list->strdup_strings)
-		die("internal error in string_list_split_in_place(): "
-		    "list->strdup_strings must not be set");
-	for (;;) {
-		count++;
-		if (maxsplit >= 0 && count > maxsplit) {
-			string_list_append(list, p);
-			return count;
-		}
-		end = strpbrk(p, delim);
-		if (end) {
-			*end = '\0';
-			string_list_append(list, p);
-			p = end + 1;
-		} else {
-			string_list_append(list, p);
-			return count;
-		}
-	}
+int string_list_split_f(struct string_list *list, const char *string,
+			const char *delim, int maxsplit, unsigned flags)
+{
+	return split_string(list, string, delim, maxsplit, 0, flags);
+}
+
+int string_list_split_in_place_f(struct string_list *list, char *string,
+			       const char *delim, int maxsplit, unsigned flags)
+{
+	return split_string(list, string, delim, maxsplit, 1, flags);
 }
diff --git a/string-list.h b/string-list.h
index 122b3186419880..2b438c7733d869 100644
--- a/string-list.h
+++ b/string-list.h
@@ -254,7 +254,7 @@ struct string_list_item *unsorted_string_list_lookup(struct string_list *list,
 void unsorted_string_list_delete_item(struct string_list *list, int i, int free_util);
 
 /**
- * Split string into substrings on character `delim` and append the
+ * Split string into substrings on characters in `delim` and append the
  * substrings to `list`.  The input string is not modified.
  * list->strdup_strings must be set, as new memory needs to be
  * allocated to hold the substrings.  If maxsplit is non-negative,
@@ -262,15 +262,15 @@ void unsorted_string_list_delete_item(struct string_list *list, int i, int free_
  * appended to list.
  *
  * Examples:
- *   string_list_split(l, "foo:bar:baz", ':', -1) -> ["foo", "bar", "baz"]
- *   string_list_split(l, "foo:bar:baz", ':', 0) -> ["foo:bar:baz"]
- *   string_list_split(l, "foo:bar:baz", ':', 1) -> ["foo", "bar:baz"]
- *   string_list_split(l, "foo:bar:", ':', -1) -> ["foo", "bar", ""]
- *   string_list_split(l, "", ':', -1) -> [""]
- *   string_list_split(l, ":", ':', -1) -> ["", ""]
+ *   string_list_split(l, "foo:bar:baz", ":", -1) -> ["foo", "bar", "baz"]
+ *   string_list_split(l, "foo:bar:baz", ":", 0) -> ["foo:bar:baz"]
+ *   string_list_split(l, "foo:bar:baz", ":", 1) -> ["foo", "bar:baz"]
+ *   string_list_split(l, "foo:bar:", ":", -1) -> ["foo", "bar", ""]
+ *   string_list_split(l, "", ":", -1) -> [""]
+ *   string_list_split(l, ":", ":", -1) -> ["", ""]
  */
 int string_list_split(struct string_list *list, const char *string,
-		      int delim, int maxsplit);
+		      const char *delim, int maxsplit);
 
 /*
  * Like string_list_split(), except that string is split in-place: the
@@ -281,4 +281,21 @@ int string_list_split(struct string_list *list, const char *string,
  */
 int string_list_split_in_place(struct string_list *list, char *string,
 			       const char *delim, int maxsplit);
+
+/* Flag bits for split_f and split_in_place_f functions */
+enum {
+	/*
+	 * trim whitespaces around resulting string piece before adding
+	 * it to the list
+	 */
+	STRING_LIST_SPLIT_TRIM = (1 << 0),
+	/* omit adding empty string piece to the resulting list */
+	STRING_LIST_SPLIT_NONEMPTY = (1 << 1),
+};
+
+int string_list_split_f(struct string_list *, const char *string,
+			const char *delim, int maxsplit, unsigned flags);
+
+int string_list_split_in_place_f(struct string_list *, char *string,
+				 const char *delim, int maxsplit, unsigned flags);
 #endif /* STRING_LIST_H */
diff --git a/sub-process.c b/sub-process.c
index 1daf5a975254b9..83bf0a0e82e56d 100644
--- a/sub-process.c
+++ b/sub-process.c
@@ -30,23 +30,20 @@ struct subprocess_entry *subprocess_find_entry(struct hashmap *hashmap, const ch
 
 int subprocess_read_status(int fd, struct strbuf *status)
 {
-	struct strbuf **pair;
-	char *line;
 	int len;
 
 	for (;;) {
+		char *line;
+		const char *value;
+
 		len = packet_read_line_gently(fd, NULL, &line);
 		if ((len < 0) || !line)
 			break;
-		pair = strbuf_split_str(line, '=', 2);
-		if (pair[0] && pair[0]->len && pair[1]) {
+		if (skip_prefix(line, "status=", &value)) {
 			/* the last "status=<foo>" line wins */
-			if (!strcmp(pair[0]->buf, "status=")) {
-				strbuf_reset(status);
-				strbuf_addbuf(status, pair[1]);
-			}
+			strbuf_reset(status);
+			strbuf_addstr(status, value);
 		}
-		strbuf_list_free(pair);
 	}
 
 	return (len < 0) ? len : 0;
diff --git a/t/helper/test-hashmap.c b/t/helper/test-hashmap.c
index 16a3145c3a07b1..56d223a2831b18 100644
--- a/t/helper/test-hashmap.c
+++ b/t/helper/test-hashmap.c
@@ -154,8 +154,8 @@ int cmd__hashmap(int argc UNUSED, const char **argv UNUSED)
 
 		/* break line into command and up to two parameters */
 		string_list_setlen(&parts, 0);
-		string_list_split_in_place(&parts, line.buf, DELIM, 2);
-		string_list_remove_empty_items(&parts, 0);
+		string_list_split_in_place_f(&parts, line.buf, DELIM, 2,
+					     STRING_LIST_SPLIT_NONEMPTY);
 
 		/* ignore empty lines */
 		if (!parts.nr)
diff --git a/t/helper/test-json-writer.c b/t/helper/test-json-writer.c
index a288069b04cb3b..f8316a7d29cdd5 100644
--- a/t/helper/test-json-writer.c
+++ b/t/helper/test-json-writer.c
@@ -492,8 +492,8 @@ static int scripted(void)
 
 		/* break line into command and zero or more tokens */
 		string_list_setlen(&parts, 0);
-		string_list_split_in_place(&parts, line, " ", -1);
-		string_list_remove_empty_items(&parts, 0);
+		string_list_split_in_place_f(&parts, line, " ", -1,
+					     STRING_LIST_SPLIT_NONEMPTY);
 
 		/* ignore empty lines */
 		if (!parts.nr || !*parts.items[0].string)
diff --git a/t/helper/test-path-utils.c b/t/helper/test-path-utils.c
index 086238c826aadb..f5f33751da620d 100644
--- a/t/helper/test-path-utils.c
+++ b/t/helper/test-path-utils.c
@@ -348,6 +348,7 @@ int cmd__path_utils(int argc, const char **argv)
 	if (argc == 4 && !strcmp(argv[1], "longest_ancestor_length")) {
 		int len;
 		struct string_list ceiling_dirs = STRING_LIST_INIT_DUP;
+		const char path_sep[] = { PATH_SEP, '\0' };
 		char *path = xstrdup(argv[2]);
 
 		/*
@@ -362,7 +363,7 @@ int cmd__path_utils(int argc, const char **argv)
 		 */
 		if (normalize_path_copy(path, path))
 			die("Path \"%s\" could not be normalized", argv[2]);
-		string_list_split(&ceiling_dirs, argv[3], PATH_SEP, -1);
+		string_list_split(&ceiling_dirs, argv[3], path_sep, -1);
 		filter_string_list(&ceiling_dirs, 0,
 				   normalize_ceiling_entry, NULL);
 		len = longest_ancestor_length(path, &ceiling_dirs);
diff --git a/t/helper/test-ref-store.c b/t/helper/test-ref-store.c
index 8d9a271845c4b6..83b06d39a36235 100644
--- a/t/helper/test-ref-store.c
+++ b/t/helper/test-ref-store.c
@@ -29,7 +29,7 @@ static unsigned int parse_flags(const char *str, struct flag_definition *defs)
 	if (!strcmp(str, "0"))
 		return 0;
 
-	string_list_split(&masks, str, ',', 64);
+	string_list_split(&masks, str, ",", 64);
 	for (size_t i = 0; i < masks.nr; i++) {
 		const char *name = masks.items[i].string;
 		struct flag_definition *def = defs;
@@ -215,7 +215,8 @@ static int cmd_for_each_reflog(struct ref_store *refs,
 	return refs_for_each_reflog(refs, each_reflog, NULL);
 }
 
-static int each_reflog_ent(struct object_id *old_oid, struct object_id *new_oid,
+static int each_reflog_ent(const char *refname UNUSED,
+			   struct object_id *old_oid, struct object_id *new_oid,
 			   const char *committer, timestamp_t timestamp,
 			   int tz, const char *msg, void *cb_data UNUSED)
 {
diff --git a/t/meson.build b/t/meson.build
index bbeba1a8d50e1b..983245501ce9a2 100644
--- a/t/meson.build
+++ b/t/meson.build
@@ -204,6 +204,7 @@ integration_tests = [
   't1418-reflog-exists.sh',
   't1419-exclude-refs.sh',
   't1420-lost-found.sh',
+  't1421-reflog-write.sh',
   't1430-bad-ref-name.sh',
   't1450-fsck.sh',
   't1451-fsck-buffer.sh',
diff --git a/t/t1421-reflog-write.sh b/t/t1421-reflog-write.sh
new file mode 100755
index 00000000000000..46df64c1761b40
--- /dev/null
+++ b/t/t1421-reflog-write.sh
@@ -0,0 +1,126 @@
+#!/bin/sh
+
+test_description='Manually write reflog entries'
+
+. ./test-lib.sh
+
+SIGNATURE="C O Mitter <committer@example.com> 1112911993 -0700"
+
+test_reflog_matches () {
+	repo="$1" &&
+	refname="$2" &&
+	cat >actual &&
+	test-tool -C "$repo" ref-store main for-each-reflog-ent "$refname" >expected &&
+	test_cmp expected actual
+}
+
+test_expect_success 'invalid number of arguments' '
+	test_when_finished "rm -rf repo" &&
+	git init repo &&
+	(
+		cd repo &&
+		for args in "" "1" "1 2" "1 2 3" "1 2 3 4 5"
+		do
+			test_must_fail git reflog write $args 2>err &&
+			test_grep "usage: git reflog write" err || return 1
+		done
+	)
+'
+
+test_expect_success 'invalid refname' '
+	test_when_finished "rm -rf repo" &&
+	git init repo &&
+	(
+		cd repo &&
+		test_must_fail git reflog write "refs/heads/ invalid" $ZERO_OID $ZERO_OID first 2>err &&
+		test_grep "invalid reference name: " err
+	)
+'
+
+test_expect_success 'unqualified refname is rejected' '
+	test_when_finished "rm -rf repo" &&
+	git init repo &&
+	(
+		cd repo &&
+		test_must_fail git reflog write unqualified $ZERO_OID $ZERO_OID first 2>err &&
+		test_grep "invalid reference name: " err
+	)
+'
+
+test_expect_success 'nonexistent object IDs' '
+	test_when_finished "rm -rf repo" &&
+	git init repo &&
+	(
+		cd repo &&
+		test_must_fail git reflog write refs/heads/something $(test_oid deadbeef) $ZERO_OID old-object-id 2>err &&
+		test_grep "old object .* does not exist" err &&
+		test_must_fail git reflog write refs/heads/something $ZERO_OID $(test_oid deadbeef) new-object-id 2>err &&
+		test_grep "new object .* does not exist" err
+	)
+'
+
+test_expect_success 'abbreviated object IDs' '
+	test_when_finished "rm -rf repo" &&
+	git init repo &&
+	(
+		cd repo &&
+		test_commit initial &&
+		abbreviated_oid=$(git rev-parse HEAD | test_copy_bytes 8) &&
+		test_must_fail git reflog write refs/heads/something $abbreviated_oid $ZERO_OID old-object-id 2>err &&
+		test_grep "invalid old object ID" err &&
+		test_must_fail git reflog write refs/heads/something $ZERO_OID $abbreviated_oid new-object-id 2>err &&
+		test_grep "invalid new object ID" err
+	)
+'
+
+test_expect_success 'reflog message gets normalized' '
+	test_when_finished "rm -rf repo" &&
+	git init repo &&
+	(
+		cd repo &&
+		test_commit initial &&
+		COMMIT_OID=$(git rev-parse HEAD) &&
+		git reflog write HEAD $COMMIT_OID $COMMIT_OID "$(printf "message\nwith\nnewlines")" &&
+		git reflog show -1 --format=%gs HEAD >actual &&
+		echo "message with newlines" >expected &&
+		test_cmp expected actual
+	)
+'
+
+test_expect_success 'simple writes' '
+	test_when_finished "rm -rf repo" &&
+	git init repo &&
+	(
+		cd repo &&
+		test_commit initial &&
+		COMMIT_OID=$(git rev-parse HEAD) &&
+
+		git reflog write refs/heads/something $ZERO_OID $COMMIT_OID first &&
+		test_reflog_matches . refs/heads/something <<-EOF &&
+		$ZERO_OID $COMMIT_OID $SIGNATURE	first
+		EOF
+
+		git reflog write refs/heads/something $COMMIT_OID $COMMIT_OID second &&
+		test_reflog_matches . refs/heads/something <<-EOF
+		$ZERO_OID $COMMIT_OID $SIGNATURE	first
+		$COMMIT_OID $COMMIT_OID $SIGNATURE	second
+		EOF
+	)
+'
+
+test_expect_success 'can write to root ref' '
+	test_when_finished "rm -rf repo" &&
+	git init repo &&
+	(
+		cd repo &&
+		test_commit initial &&
+		COMMIT_OID=$(git rev-parse HEAD) &&
+
+		git reflog write ROOT_REF_HEAD $ZERO_OID $COMMIT_OID first &&
+		test_reflog_matches . ROOT_REF_HEAD <<-EOF
+		$ZERO_OID $COMMIT_OID $SIGNATURE	first
+		EOF
+	)
+'
+
+test_done
diff --git a/t/t1460-refs-migrate.sh b/t/t1460-refs-migrate.sh
index 2ab97e1b7dfa7e..0e1116a319d53d 100755
--- a/t/t1460-refs-migrate.sh
+++ b/t/t1460-refs-migrate.sh
@@ -7,6 +7,17 @@ export GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME
 
 . ./test-lib.sh
 
+print_all_reflog_entries () {
+	repo=$1 &&
+	test-tool -C "$repo" ref-store main for-each-reflog >reflogs &&
+	while read reflog
+	do
+		echo "REFLOG: $reflog" &&
+		test-tool -C "$repo" ref-store main for-each-reflog-ent "$reflog" ||
+		return 1
+	done <reflogs
+}
+
 # Migrate the provided repository from one format to the other and
 # verify that the references and logs are migrated over correctly.
 # Usage: test_migration <repo> <format> [<skip_reflog_verify> [<options...>]]
@@ -28,8 +39,7 @@ test_migration () {
 		--format='%(refname) %(objectname) %(symref)' >expect &&
 	if ! $skip_reflog_verify
 	then
-	   git -C "$repo" reflog --all >expect_logs &&
-	   git -C "$repo" reflog list >expect_log_list
+		print_all_reflog_entries "$repo" >expect_logs
 	fi &&
 
 	git -C "$repo" refs migrate --ref-format="$format" "$@" &&
@@ -39,10 +49,8 @@ test_migration () {
 	test_cmp expect actual &&
 	if ! $skip_reflog_verify
 	then
-		git -C "$repo" reflog --all >actual_logs &&
-		git -C "$repo" reflog list >actual_log_list &&
-		test_cmp expect_logs actual_logs &&
-		test_cmp expect_log_list actual_log_list
+		print_all_reflog_entries "$repo" >actual_logs &&
+		test_cmp expect_logs actual_logs
 	fi &&
 
 	git -C "$repo" rev-parse --show-ref-format >actual &&
@@ -273,7 +281,7 @@ test_expect_success 'multiple reftable blocks with multiple entries' '
 	test_commit -C repo second &&
 	printf "update refs/heads/ref-%d HEAD\n" $(test_seq 3000) >stdin &&
 	git -C repo update-ref --stdin <stdin &&
-	test_migration repo reftable
+	test_migration repo reftable true
 '
 
 test_expect_success 'migrating from files format deletes backend files' '
diff --git a/t/t1517-outside-repo.sh b/t/t1517-outside-repo.sh
index 8f59b867f2701f..3dc602872a0037 100755
--- a/t/t1517-outside-repo.sh
+++ b/t/t1517-outside-repo.sh
@@ -107,18 +107,32 @@ test_expect_success LIBCURL 'remote-http outside repository' '
 	test_grep "^error: remote-curl" actual
 '
 
-test_expect_success 'update-server-info does not crash with -h' '
-	test_expect_code 129 git update-server-info -h >usage &&
-	test_grep "[Uu]sage: git update-server-info " usage &&
-	test_expect_code 129 nongit git update-server-info -h >usage &&
-	test_grep "[Uu]sage: git update-server-info " usage
-'
-
-test_expect_success 'prune does not crash with -h' '
-	test_expect_code 129 git prune -h >usage &&
-	test_grep "[Uu]sage: git prune " usage &&
-	test_expect_code 129 nongit git prune -h >usage &&
-	test_grep "[Uu]sage: git prune " usage
-'
+for cmd in $(git --list-cmds=main)
+do
+	cmd=${cmd%.*} # strip .sh, .perl, etc.
+	case "$cmd" in
+	archimport | cvsexportcommit | cvsimport | cvsserver | daemon | \
+	difftool--helper | filter-branch | fsck-objects | get-tar-commit-id | \
+	http-backend | http-fetch | http-push | init-db | \
+	merge-octopus | merge-one-file | merge-resolve | mergetool | \
+	mktag | p4 | p4.py | pickaxe | remote-ftp | remote-ftps | \
+	remote-http | remote-https | replay | send-email | \
+	sh-i18n--envsubst | shell | show | stage | submodule | svn | \
+	upload-archive--writer | upload-pack | web--browse | whatchanged)
+		expect_outcome=expect_failure ;;
+	*)
+		expect_outcome=expect_success ;;
+	esac
+	case "$cmd" in
+	instaweb)
+		prereq=PERL ;;
+	*)
+		prereq= ;;
+	esac
+	test_$expect_outcome $prereq "'git $cmd -h' outside a repository" '
+		test_expect_code 129 nongit git $cmd -h >usage &&
+		test_grep "[Uu]sage: git $cmd " usage
+	'
+done
 
 test_done
diff --git a/t/t3404-rebase-interactive.sh b/t/t3404-rebase-interactive.sh
index 6bac217ed3555e..34d6ad07709741 100755
--- a/t/t3404-rebase-interactive.sh
+++ b/t/t3404-rebase-interactive.sh
@@ -2263,6 +2263,7 @@ test_expect_success 'non-merge commands reject merge commits' '
 	edit $oid
 	fixup $oid
 	squash $oid
+	drop $oid # acceptable, no advice
 	EOF
 	(
 		set_replace_editor todo &&
diff --git a/t/t4216-log-bloom.sh b/t/t4216-log-bloom.sh
index 639868ac562f9e..1064990de31413 100755
--- a/t/t4216-log-bloom.sh
+++ b/t/t4216-log-bloom.sh
@@ -154,11 +154,34 @@ test_expect_success 'git log with multiple literal paths uses Bloom filter' '
 	test_bloom_filters_used "-- file*"
 '
 
-test_expect_success 'git log with path contains a wildcard does not use Bloom filter' '
+test_expect_success 'git log with paths all contain non-wildcard part uses Bloom filter' '
+	test_bloom_filters_used "-- A/\* file4" &&
+	test_bloom_filters_used "-- A/file\*" &&
+	test_bloom_filters_used "-- * A/\*"
+'
+
+test_expect_success 'git log with path only contains wildcard part does not use Bloom filter' '
 	test_bloom_filters_not_used "-- file\*" &&
-	test_bloom_filters_not_used "-- A/\* file4" &&
-	test_bloom_filters_not_used "-- file4 A/\*" &&
-	test_bloom_filters_not_used "-- * A/\*"
+	test_bloom_filters_not_used "-- file\* A/\*" &&
+	test_bloom_filters_not_used "-- file\* *" &&
+	test_bloom_filters_not_used "-- \*"
+'
+
+test_expect_success 'git log with path contains various magic signatures' '
+	cd A &&
+	test_bloom_filters_used "-- \:\(top\)B" &&
+	cd .. &&
+
+	test_bloom_filters_used "-- \:\(glob\)A/\*\*/C" &&
+	test_bloom_filters_not_used "-- \:\(icase\)FILE4" &&
+	test_bloom_filters_not_used "-- \:\(exclude\)A/B/C" &&
+
+	test_when_finished "rm -f .gitattributes" &&
+	cat >.gitattributes <<-EOF &&
+	A/file1 text
+	A/B/file2 -text
+	EOF
+	test_bloom_filters_used "-- \:\(attr\:text\)A"
 '
 
 test_expect_success 'setup - add commit-graph to the chain without Bloom filters' '
diff --git a/t/t5200-update-server-info.sh b/t/t5200-update-server-info.sh
index 83659070559952..a551e955b5524b 100755
--- a/t/t5200-update-server-info.sh
+++ b/t/t5200-update-server-info.sh
@@ -46,4 +46,9 @@ test_expect_success 'midx does not create duplicate pack entries' '
 	test_must_be_empty dups
 '
 
+test_expect_success 'update-server-info does not crash with -h' '
+	test_expect_code 129 git update-server-info -h >usage &&
+	test_grep "[Uu]sage: git update-server-info " usage
+'
+
 test_done
diff --git a/t/t5304-prune.sh b/t/t5304-prune.sh
index 1f1f664871ece6..2be7cd30dece6e 100755
--- a/t/t5304-prune.sh
+++ b/t/t5304-prune.sh
@@ -364,4 +364,9 @@ test_expect_success 'gc.recentObjectsHook' '
 	git cat-file -p $BLOB
 '
 
+test_expect_success 'prune does not crash with -h' '
+	test_expect_code 129 git prune -h >usage &&
+	test_grep "[Uu]sage: git prune " usage
+'
+
 test_done
diff --git a/t/t5505-remote.sh b/t/t5505-remote.sh
index 2701eef85e9ef8..e592c0bcde91e9 100755
--- a/t/t5505-remote.sh
+++ b/t/t5505-remote.sh
@@ -1658,4 +1658,77 @@ test_expect_success 'forbid adding superset of existing remote' '
 	test_grep ".outer. is a superset of existing remote .outer/inner." err
 '
 
+test_expect_success 'rename handles unborn HEAD' '
+	test_when_finished "git remote remove unborn-renamed" &&
+	git remote add unborn url &&
+	git symbolic-ref refs/remotes/unborn/HEAD refs/remotes/unborn/nonexistent &&
+	git remote rename unborn unborn-renamed &&
+	git symbolic-ref refs/remotes/unborn-renamed/HEAD >actual &&
+	echo refs/remotes/unborn-renamed/nonexistent >expected &&
+	test_cmp expected actual
+'
+
+test_expect_success 'rename can nest a remote into itself' '
+	test_commit parent-commit &&
+	COMMIT_ID=$(git rev-parse HEAD) &&
+	test_when_finished "git remote remove parent || true" &&
+	git remote add parent url &&
+	git update-ref refs/remotes/parent/branch $COMMIT_ID &&
+	test_when_finished "git remote remove parent/child" &&
+	git remote rename parent parent/child &&
+	git for-each-ref refs/remotes/ >actual &&
+	printf "$COMMIT_ID commit\trefs/remotes/parent/child/branch\n" >expected &&
+	test_cmp expected actual
+'
+
+test_expect_success 'rename can nest a remote into itself with a conflicting branch name' '
+	test_commit parent-conflict &&
+	COMMIT_ID=$(git rev-parse HEAD) &&
+	test_when_finished "git remote remove parent || true" &&
+	git remote add parent url &&
+	git update-ref refs/remotes/parent/child $COMMIT_ID &&
+	test_when_finished "git remote remove parent/child" &&
+	test_must_fail git remote rename parent parent/child 2>err &&
+	test_grep "renaming remote references failed" err &&
+	test_grep "The remote you are trying to rename has conflicting references" err &&
+	git for-each-ref refs/remotes/ >actual &&
+	printf "$COMMIT_ID commit\trefs/remotes/parent/child\n" >expected &&
+	test_cmp expected actual
+'
+
+test_expect_success 'rename can unnest a remote' '
+	test_commit parent-child-commit &&
+	COMMIT_ID=$(git rev-parse HEAD) &&
+	test_when_finished "git remote remove parent/child || true" &&
+	git remote add parent/child url &&
+	git update-ref refs/remotes/parent/child/branch $COMMIT_ID &&
+	git remote rename parent/child parent &&
+	git for-each-ref refs/remotes/ >actual &&
+	printf "$COMMIT_ID commit\trefs/remotes/parent/branch\n" >expected &&
+	test_cmp expected actual
+'
+
+test_expect_success 'rename moves around the reflog' '
+	test_commit reflog-old &&
+	COMMIT_ID=$(git rev-parse HEAD) &&
+	test_config core.logAllRefUpdates true &&
+	test_when_finished "git remote remove reflog-old || true" &&
+	git remote add reflog-old url &&
+	git update-ref refs/remotes/reflog-old/branch $COMMIT_ID &&
+	test-tool ref-store main for-each-reflog >actual &&
+	test_grep refs/remotes/reflog-old/branch actual &&
+	test-tool ref-store main for-each-reflog-ent refs/remotes/reflog-old/branch >reflog-entries-old &&
+	test_line_count = 1 reflog-entries-old &&
+	git remote rename reflog-old reflog-new &&
+	test-tool ref-store main for-each-reflog >actual &&
+	test_grep ! refs/remotes/reflog-old actual &&
+	test_grep refs/remotes/reflog-new/branch actual &&
+	test-tool ref-store main for-each-reflog-ent refs/remotes/reflog-new/branch >reflog-entries-new &&
+	cat >expect <<-EOF &&
+	$(cat reflog-entries-old)
+	$COMMIT_ID $COMMIT_ID $GIT_COMMITTER_NAME <$GIT_COMMITTER_EMAIL> 1112912173 -0700	remote: renamed refs/remotes/reflog-old/branch to refs/remotes/reflog-new/branch
+	EOF
+	test_cmp expect reflog-entries-new
+'
+
 test_done
diff --git a/t/t5516-fetch-push.sh b/t/t5516-fetch-push.sh
index 4e9c27b0f28fd7..46926e7bbd3a9a 100755
--- a/t/t5516-fetch-push.sh
+++ b/t/t5516-fetch-push.sh
@@ -105,7 +105,6 @@ check_push_result () {
 }
 
 test_expect_success setup '
-
 	>path1 &&
 	git add path1 &&
 	test_tick &&
@@ -117,7 +116,6 @@ test_expect_success setup '
 	test_tick &&
 	git commit -a -m second &&
 	the_commit=$(git show-ref -s --verify refs/heads/main)
-
 '
 
 for cmd in push fetch
@@ -322,104 +320,82 @@ test_expect_success 'push with pushInsteadOf and explicit pushurl (pushInsteadOf
 '
 
 test_expect_success 'push with matching heads' '
-
 	mk_test testrepo heads/main &&
 	git push testrepo : &&
 	check_push_result testrepo $the_commit heads/main
-
 '
 
 test_expect_success 'push with matching heads on the command line' '
-
 	mk_test testrepo heads/main &&
 	git push testrepo : &&
 	check_push_result testrepo $the_commit heads/main
-
 '
 
 test_expect_success 'failed (non-fast-forward) push with matching heads' '
-
 	mk_test testrepo heads/main &&
 	git push testrepo : &&
 	git commit --amend -massaged &&
 	test_must_fail git push testrepo &&
 	check_push_result testrepo $the_commit heads/main &&
 	git reset --hard $the_commit
-
 '
 
 test_expect_success 'push --force with matching heads' '
-
 	mk_test testrepo heads/main &&
 	git push testrepo : &&
 	git commit --amend -massaged &&
 	git push --force testrepo : &&
 	! check_push_result testrepo $the_commit heads/main &&
 	git reset --hard $the_commit
-
 '
 
 test_expect_success 'push with matching heads and forced update' '
-
 	mk_test testrepo heads/main &&
 	git push testrepo : &&
 	git commit --amend -massaged &&
 	git push testrepo +: &&
 	! check_push_result testrepo $the_commit heads/main &&
 	git reset --hard $the_commit
-
 '
 
 test_expect_success 'push with no ambiguity (1)' '
-
 	mk_test testrepo heads/main &&
 	git push testrepo main:main &&
 	check_push_result testrepo $the_commit heads/main
-
 '
 
 test_expect_success 'push with no ambiguity (2)' '
-
 	mk_test testrepo remotes/origin/main &&
 	git push testrepo main:origin/main &&
 	check_push_result testrepo $the_commit remotes/origin/main
-
 '
 
 test_expect_success 'push with colon-less refspec, no ambiguity' '
-
 	mk_test testrepo heads/main heads/t/main &&
 	git branch -f t/main main &&
 	git push testrepo main &&
 	check_push_result testrepo $the_commit heads/main &&
 	check_push_result testrepo $the_first_commit heads/t/main
-
 '
 
 test_expect_success 'push with weak ambiguity (1)' '
-
 	mk_test testrepo heads/main remotes/origin/main &&
 	git push testrepo main:main &&
 	check_push_result testrepo $the_commit heads/main &&
 	check_push_result testrepo $the_first_commit remotes/origin/main
-
 '
 
 test_expect_success 'push with weak ambiguity (2)' '
-
 	mk_test testrepo heads/main remotes/origin/main remotes/another/main &&
 	git push testrepo main:main &&
 	check_push_result testrepo $the_commit heads/main &&
 	check_push_result testrepo $the_first_commit remotes/origin/main remotes/another/main
-
 '
 
 test_expect_success 'push with ambiguity' '
-
 	mk_test testrepo heads/frotz tags/frotz &&
 	test_must_fail git push testrepo main:frotz &&
 	check_push_result testrepo $the_first_commit heads/frotz tags/frotz
-
 '
 
 test_expect_success 'push with onelevel ref' '
@@ -428,17 +404,14 @@ test_expect_success 'push with onelevel ref' '
 '
 
 test_expect_success 'push with colon-less refspec (1)' '
-
 	mk_test testrepo heads/frotz tags/frotz &&
 	git branch -f frotz main &&
 	git push testrepo frotz &&
 	check_push_result testrepo $the_commit heads/frotz &&
 	check_push_result testrepo $the_first_commit tags/frotz
-
 '
 
 test_expect_success 'push with colon-less refspec (2)' '
-
 	mk_test testrepo heads/frotz tags/frotz &&
 	if git show-ref --verify -q refs/heads/frotz
 	then
@@ -448,7 +421,6 @@ test_expect_success 'push with colon-less refspec (2)' '
 	git push -f testrepo frotz &&
 	check_push_result testrepo $the_commit tags/frotz &&
 	check_push_result testrepo $the_first_commit heads/frotz
-
 '
 
 test_expect_success 'push with colon-less refspec (3)' '
@@ -465,7 +437,6 @@ test_expect_success 'push with colon-less refspec (3)' '
 '
 
 test_expect_success 'push with colon-less refspec (4)' '
-
 	mk_test testrepo &&
 	if git show-ref --verify -q refs/heads/frotz
 	then
@@ -475,38 +446,34 @@ test_expect_success 'push with colon-less refspec (4)' '
 	git push testrepo frotz &&
 	check_push_result testrepo $the_commit tags/frotz &&
 	test 1 = $( cd testrepo && git show-ref | wc -l )
-
 '
 
 test_expect_success 'push head with non-existent, incomplete dest' '
-
 	mk_test testrepo &&
 	git push testrepo main:branch &&
 	check_push_result testrepo $the_commit heads/branch
-
 '
 
 test_expect_success 'push tag with non-existent, incomplete dest' '
-
 	mk_test testrepo &&
 	git tag -f v1.0 &&
 	git push testrepo v1.0:tag &&
 	check_push_result testrepo $the_commit tags/tag
-
 '
 
 test_expect_success 'push oid with non-existent, incomplete dest' '
-
 	mk_test testrepo &&
 	test_must_fail git push testrepo $(git rev-parse main):foo
-
 '
 
 test_expect_success 'push ref expression with non-existent, incomplete dest' '
-
 	mk_test testrepo &&
 	test_must_fail git push testrepo main^:branch
+'
 
+test_expect_success 'push ref expression with non-existent oid src' '
+	mk_test testrepo &&
+	test_must_fail git push testrepo $(test_oid 001):branch
 '
 
 for head in HEAD @
@@ -550,7 +517,6 @@ do
 		git checkout main &&
 		git push testrepo $head:branch &&
 		check_push_result testrepo $the_commit heads/branch
-
 	'
 
 	test_expect_success "push with config remote.*.push = $head" '
@@ -596,7 +562,6 @@ test_expect_success 'push with remote.pushdefault' '
 '
 
 test_expect_success 'push with config remote.*.pushurl' '
-
 	mk_test testrepo heads/main &&
 	git checkout main &&
 	test_config remote.there.url test2repo &&
@@ -655,7 +620,6 @@ test_expect_success 'push ignores "branch." config without subsection' '
 '
 
 test_expect_success 'push with dry-run' '
-
 	mk_test testrepo heads/main &&
 	old_commit=$(git -C testrepo show-ref -s --verify refs/heads/main) &&
 	git push --dry-run testrepo : &&
@@ -663,7 +627,6 @@ test_expect_success 'push with dry-run' '
 '
 
 test_expect_success 'push updates local refs' '
-
 	mk_test testrepo heads/main &&
 	mk_child testrepo child &&
 	(
@@ -673,11 +636,9 @@ test_expect_success 'push updates local refs' '
 		test $(git rev-parse main) = \
 			$(git rev-parse remotes/origin/main)
 	)
-
 '
 
 test_expect_success 'push updates up-to-date local refs' '
-
 	mk_test testrepo heads/main &&
 	mk_child testrepo child1 &&
 	mk_child testrepo child2 &&
@@ -689,11 +650,9 @@ test_expect_success 'push updates up-to-date local refs' '
 		test $(git rev-parse main) = \
 			$(git rev-parse remotes/origin/main)
 	)
-
 '
 
 test_expect_success 'push preserves up-to-date packed refs' '
-
 	mk_test testrepo heads/main &&
 	mk_child testrepo child &&
 	(
@@ -701,11 +660,9 @@ test_expect_success 'push preserves up-to-date packed refs' '
 		git push &&
 		! test -f .git/refs/remotes/origin/main
 	)
-
 '
 
 test_expect_success 'push does not update local refs on failure' '
-
 	mk_test testrepo heads/main &&
 	mk_child testrepo child &&
 	echo "#!/no/frobnication/today" >testrepo/.git/hooks/pre-receive &&
@@ -717,16 +674,13 @@ test_expect_success 'push does not update local refs on failure' '
 		test $(git rev-parse main) != \
 			$(git rev-parse remotes/origin/main)
 	)
-
 '
 
 test_expect_success 'allow deleting an invalid remote ref' '
-
 	mk_test testrepo heads/branch &&
 	rm -f testrepo/.git/objects/??/* &&
 	git push testrepo :refs/heads/branch &&
 	(cd testrepo && test_must_fail git rev-parse --verify refs/heads/branch)
-
 '
 
 test_expect_success 'pushing valid refs triggers post-receive and post-update hooks' '
diff --git a/t/t6137-pathspec-wildcards-literal.sh b/t/t6137-pathspec-wildcards-literal.sh
index 20abad5667df28..17a03085ef396d 100755
--- a/t/t6137-pathspec-wildcards-literal.sh
+++ b/t/t6137-pathspec-wildcards-literal.sh
@@ -3,8 +3,8 @@ test_description='test wildcards and literals with git add/commit (subshell styl
 
 . ./test-lib.sh
 
-test_have_prereq FUNNYNAMES || {
-	skip_all='skipping: needs FUNNYNAMES (non-Windows only)'
+test_have_prereq BSLASHPSPEC || {
+	skip_all='skipping: needs BSLASHPSPEC (backslashes in pathspecs)'
 	test_done
 }
 
@@ -184,7 +184,7 @@ test_expect_success 'add wildcard f?z' '
 	)
 '
 
-test_expect_success 'add literal \? literal' '
+test_expect_success 'add literal \?' '
 	git init test-q-lit &&
 	(
 		cd test-q-lit &&
@@ -241,7 +241,7 @@ test_expect_success 'add literal hello\?world' '
 	)
 '
 
-test_expect_success 'add literal [abc]' '
+test_expect_success 'add literal \[abc\]' '
 	git init test-brackets-lit &&
 	(
 		cd test-brackets-lit &&
@@ -280,7 +280,7 @@ test_expect_success 'commit: wildcard *' '
 	)
 '
 
-test_expect_success 'commit: literal *' '
+test_expect_success 'commit: literal \*' '
 	git init test-c-asterisk-lit &&
 	(
 		cd test-c-asterisk-lit &&
@@ -328,7 +328,7 @@ test_expect_success 'commit: literal f\*' '
 	)
 '
 
-test_expect_success 'commit: wildcard pathspec limits commit' '
+test_expect_success 'commit: wildcard f**' '
 	git init test-c-pathlimit &&
 	(
 		cd test-c-pathlimit &&
diff --git a/t/t6423-merge-rename-directories.sh b/t/t6423-merge-rename-directories.sh
index f48ed6d03534ee..533ac85dc83409 100755
--- a/t/t6423-merge-rename-directories.sh
+++ b/t/t6423-merge-rename-directories.sh
@@ -4731,7 +4731,7 @@ test_setup_12i () {
 
 		mkdir -p source/subdir &&
 		echo foo >source/subdir/foo &&
-		echo bar >source/bar &&
+		printf "%d\n" 1 2 3 4 5 6 7 >source/bar &&
 		echo baz >source/baz &&
 		git add source &&
 		git commit -m orig &&
@@ -4747,6 +4747,7 @@ test_setup_12i () {
 		git switch B &&
 		git mv source/bar source/subdir/bar &&
 		echo more baz >>source/baz &&
+		git add source/baz &&
 		git commit -m B
 	)
 }
@@ -4758,6 +4759,88 @@ test_expect_success '12i: Directory rename causes rename-to-self' '
 
 		git checkout A^0 &&
 
+		# NOTE: A potentially better resolution would be for
+		#     source/bar -> source/subdir/bar
+		# to use the directory rename to become
+		#     source/bar -> source/bar
+		# (a rename to self), and thus we end up with bar with
+		# a path conflict (given merge.directoryRenames=conflict).
+		# However, since the relevant renames optimization
+		# prevents us from noticing
+		#     source/bar -> source/subdir/bar
+		# as a rename and looking at it just as
+		#     delete source/bar
+		#     add source/subdir/bar
+		# the directory rename of source/subdir/bar -> source/bar does
+		# not look like a rename-to-self situation but a
+		# rename-on-top-of-other-file situation.  We do not want
+		# stage 1 entries from an unrelated file, so we expect an
+		# error about there being a file in the way.
+
+		test_must_fail git -c merge.directoryRenames=conflict merge -s recursive B^0 >out &&
+
+		grep "CONFLICT (implicit dir rename).*source/bar in the way" out &&
+		test_path_is_missing source/bar &&
+		test_path_is_file source/subdir/bar &&
+		test_path_is_file source/baz &&
+
+		git ls-files >actual &&
+		uniq <actual >tracked &&
+		test_line_count = 3 tracked &&
+
+		git status --porcelain -uno >actual &&
+		cat >expect <<-\EOF &&
+		M  source/baz
+		R  source/bar -> source/subdir/bar
+		EOF
+		test_cmp expect actual
+	)
+'
+
+# Testcase 12i2, Identical to 12i except that source/subdir/bar modified on unrenamed side
+#   Commit O: source/{subdir/foo, bar, baz_1}
+#   Commit A: source/{foo, bar_2, baz_1}
+#   Commit B: source/{subdir/{foo, bar}, baz_2}
+#   Expected: source/{foo, bar, baz_2}, with conflicts on
+#                source/bar vs. source/subdir/bar
+
+test_setup_12i2 () {
+	git init 12i2 &&
+	(
+		cd 12i2 &&
+
+		mkdir -p source/subdir &&
+		echo foo >source/subdir/foo &&
+		printf "%d\n" 1 2 3 4 5 6 7 >source/bar &&
+		echo baz >source/baz &&
+		git add source &&
+		git commit -m orig &&
+
+		git branch O &&
+		git branch A &&
+		git branch B &&
+
+		git switch A &&
+		git mv source/subdir/foo source/foo &&
+		echo 8 >> source/bar &&
+		git add source/bar &&
+		git commit -m A &&
+
+		git switch B &&
+		git mv source/bar source/subdir/bar &&
+		echo more baz >>source/baz &&
+		git add source/baz &&
+		git commit -m B
+	)
+}
+
+test_expect_success '12i2: Directory rename causes rename-to-self' '
+	test_setup_12i2 &&
+	(
+		cd 12i2 &&
+
+		git checkout A^0 &&
+
 		test_must_fail git -c merge.directoryRenames=conflict merge -s recursive B^0 &&
 
 		test_path_is_missing source/subdir &&
@@ -4771,7 +4854,7 @@ test_expect_success '12i: Directory rename causes rename-to-self' '
 		git status --porcelain -uno >actual &&
 		cat >expect <<-\EOF &&
 		UU source/bar
-		 M source/baz
+		M  source/baz
 		EOF
 		test_cmp expect actual
 	)
@@ -4806,6 +4889,7 @@ test_setup_12j () {
 		git switch B &&
 		git mv bar subdir/bar &&
 		echo more baz >>baz &&
+		git add baz &&
 		git commit -m B
 	)
 }
@@ -4817,10 +4901,29 @@ test_expect_success '12j: Directory rename to root causes rename-to-self' '
 
 		git checkout A^0 &&
 
-		test_must_fail git -c merge.directoryRenames=conflict merge -s recursive B^0 &&
-
-		test_path_is_missing subdir &&
-		test_path_is_file bar &&
+		# NOTE: A potentially better resolution would be for
+		#     bar -> subdir/bar
+		# to use the directory rename to become
+		#     bar -> bar
+		# (a rename to self), and thus we end up with bar with
+		# a path conflict (given merge.directoryRenames=conflict).
+		# However, since the relevant renames optimization
+		# prevents us from noticing
+		#     bar -> subdir/bar
+		# as a rename and looking at it just as
+		#     delete bar
+		#     add subdir/bar
+		# the directory rename of subdir/bar -> bar does not look
+		# like a rename-to-self situation but a
+		# rename-on-top-of-other-file situation.  We do not want
+		# stage 1 entries from an unrelated file, so we expect an
+		# error about there being a file in the way.
+
+		test_must_fail git -c merge.directoryRenames=conflict merge -s recursive B^0 >out &&
+		grep "CONFLICT (implicit dir rename).*bar in the way" out &&
+
+		test_path_is_missing bar &&
+		test_path_is_file subdir/bar &&
 		test_path_is_file baz &&
 
 		git ls-files >actual &&
@@ -4829,8 +4932,8 @@ test_expect_success '12j: Directory rename to root causes rename-to-self' '
 
 		git status --porcelain -uno >actual &&
 		cat >expect <<-\EOF &&
-		UU bar
-		 M baz
+		M  baz
+		R  bar -> subdir/bar
 		EOF
 		test_cmp expect actual
 	)
@@ -4865,6 +4968,7 @@ test_setup_12k () {
 		git switch B &&
 		git mv dirA/bar dirB/bar &&
 		echo more baz >>dirA/baz &&
+		git add dirA/baz &&
 		git commit -m B
 	)
 }
@@ -4876,10 +4980,29 @@ test_expect_success '12k: Directory rename with sibling causes rename-to-self' '
 
 		git checkout A^0 &&
 
-		test_must_fail git -c merge.directoryRenames=conflict merge -s recursive B^0 &&
-
-		test_path_is_missing dirB &&
-		test_path_is_file dirA/bar &&
+		# NOTE: A potentially better resolution would be for
+		#     dirA/bar -> dirB/bar
+		# to use the directory rename (dirB/ -> dirA/) to become
+		#     dirA/bar -> dirA/bar
+		# (a rename to self), and thus we end up with bar with
+		# a path conflict (given merge.directoryRenames=conflict).
+		# However, since the relevant renames optimization
+		# prevents us from noticing
+		#     dirA/bar -> dirB/bar
+		# as a rename and looking at it just as
+		#     delete dirA/bar
+		#     add dirB/bar
+		# the directory rename of dirA/bar -> dirB/bar does
+		# not look like a rename-to-self situation but a
+		# rename-on-top-of-other-file situation.  We do not want
+		# stage 1 entries from an unrelated file, so we expect an
+		# error about there being a file in the way.
+
+		test_must_fail git -c merge.directoryRenames=conflict merge -s recursive B^0 >out &&
+		grep "CONFLICT (implicit dir rename).*dirA/bar in the way" out &&
+
+		test_path_is_missing dirA/bar &&
+		test_path_is_file dirB/bar &&
 		test_path_is_file dirA/baz &&
 
 		git ls-files >actual &&
@@ -4888,8 +5011,8 @@ test_expect_success '12k: Directory rename with sibling causes rename-to-self' '
 
 		git status --porcelain -uno >actual &&
 		cat >expect <<-\EOF &&
-		UU dirA/bar
-		 M dirA/baz
+		M  dirA/baz
+		R  dirA/bar -> dirB/bar
 		EOF
 		test_cmp expect actual
 	)
@@ -5056,6 +5179,25 @@ test_expect_success '12m: Change parent of renamed-dir to symlink on other side'
 	)
 '
 
+# Testcase 12n, Directory rename transitively makes rename back to self
+#
+# (Since this is a cherry-pick instead of merge, the labels are a bit weird.
+#  O, the original commit, is A~1 rather than what branch O points to.)
+#
+#   Commit O:  tools/hello
+#              world
+#   Commit A:  tools/hello
+#              tools/world
+#   Commit B:  hello
+#   In words:
+#     A: world -> tools/world
+#     B: tools/ -> /, i.e. rename all of tools to toplevel directory
+#        delete world
+#
+#   Expected:
+#             CONFLICT (file location): tools/world vs. world
+#
+
 test_setup_12n () {
 	git init 12n &&
 	(
@@ -5092,10 +5234,357 @@ test_expect_success '12n: Directory rename transitively makes rename back to sel
 		git checkout -q B^0 &&
 
 		test_must_fail git cherry-pick A^0 >out &&
-		grep "CONFLICT (file location).*should perhaps be moved" out
+		test_grep "CONFLICT (file location).*should perhaps be moved" out &&
+
+		# Should have 1 entry for hello, and 2 for world
+		test_stdout_line_count = 3 git ls-files -s &&
+		test_stdout_line_count = 1 git ls-files -s hello &&
+		test_stdout_line_count = 2 git ls-files -s world
+	)
+'
+
+# Testcase 12n2, Directory rename transitively makes rename back to self
+#
+#   Commit O:  tools/hello
+#              world
+#   Commit A:  tools/hello
+#              tools/world
+#   Commit B:  hello
+#   In words:
+#     A: world -> tools/world
+#     B: tools/ -> /, i.e. rename all of tools to toplevel directory
+#        delete world
+#
+#   Expected:
+#             CONFLICT (file location): tools/world vs. world
+#
+
+test_setup_12n2 () {
+	git init 12n2 &&
+	(
+		cd 12n2 &&
+
+		mkdir tools &&
+		echo hello >tools/hello &&
+		git add tools/hello &&
+		echo world >world &&
+		git add world &&
+		git commit -m "O" &&
+
+		git branch O &&
+		git branch A &&
+		git branch B &&
+
+		git switch A &&
+		git mv world tools/world &&
+		git commit -m "Move world into tools/" &&
+
+		git switch B &&
+		git mv tools/hello hello &&
+		git rm world &&
+		git commit -m "Move hello from tools/ to toplevel"
+	)
+}
+
+test_expect_success '12n2: Directory rename transitively makes rename back to self' '
+	test_setup_12n2 &&
+	(
+		cd 12n2 &&
+
+		git checkout -q B^0 &&
+
+		test_might_fail git -c merge.directoryRenames=true merge A^0 >out &&
+
+		# Should have 1 entry for hello, and either 0 or 2 for world
+		#
+		# NOTE: Since merge.directoryRenames=true, there is no path
+		# conflict for world vs. tools/world; it should end up at
+		# world.  The fact that world was unmodified on side A, means
+		# there was no content conflict; we should just take the
+		# content from side B -- i.e. delete the file.  So merging
+		# could just delete world.
+		#
+		# However, rename-to-self-via-directory-rename is a bit more
+		# challenging.  Relax this test to allow world to be treated
+		# as a modify/delete conflict as well, meaning it will have
+		# two higher order stages, that just so happen to match.
+		#
+		test_stdout_line_count = 1 git ls-files -s hello &&
+		test_stdout_line_count = 2 git ls-files -s world &&
+		test_grep "CONFLICT (modify/delete).*world deleted in HEAD" out
 	)
 '
 
+# Testcase 12o, Directory rename hits other rename source; file still in way on same side
+#   Commit O:  A/file1_1
+#              A/stuff
+#              B/file1_2
+#              B/stuff
+#              C/other
+#   Commit A:  A/file1_1
+#              A/stuff
+#              B/stuff
+#              C/file1_2
+#              C/other
+#   Commit B:  D/file2_1
+#              A/stuff
+#              B/file1_2
+#              B/stuff
+#              A/other
+#   In words:
+#     A: rename B/file1_2 -> C/file1_2
+#     B: rename C/ -> A/
+#        rename A/file1_1 -> D/file2_1
+#   Rationale:
+#       A/stuff is unmodified, it shows up in final output
+#       B/stuff is unmodified, it shows up in final output
+#       C/other touched on one side (rename to A), so A/other shows up in output
+#       A/file1 is renamed to D/file2
+#       B/file1 -> C/file1 and even though C/ -> A/, A/file1 is
+#               "in the way" so we don't do the directory rename
+#   Expected:  A/stuff
+#              B/stuff
+#              A/other
+#              D/file2
+#              C/file1
+#              + CONFLICT (implicit dir rename): A/file1 in way of C/file1
+#
+
+test_setup_12o () {
+	git init 12o &&
+	(
+		cd 12o &&
+
+		mkdir -p A B C &&
+		echo 1 >A/file1 &&
+		echo 2 >B/file1 &&
+		echo other >C/other &&
+		echo Astuff >A/stuff &&
+		echo Bstuff >B/stuff &&
+		git add . &&
+		git commit -m "O" &&
+
+		git branch O &&
+		git branch A &&
+		git branch B &&
+
+		git switch A &&
+		git mv B/file1 C/ &&
+		git add . &&
+		git commit -m "A" &&
+
+		git switch B &&
+		mkdir -p D &&
+		git mv A/file1 D/file2 &&
+		git mv C/other A/other &&
+		git add . &&
+		git commit -m "B"
+	)
+}
+
+test_expect_success '12o: Directory rename hits other rename source; file still in way on same side' '
+	test_setup_12o &&
+	(
+		cd 12o &&
+
+		git checkout -q A^0 &&
+
+		test_must_fail git -c merge.directoryRenames=conflict merge -s recursive B^0 >out &&
+
+		test_stdout_line_count = 5 git ls-files -s &&
+		test_stdout_line_count = 1 git ls-files -s A/other &&
+		test_stdout_line_count = 1 git ls-files -s A/stuff &&
+		test_stdout_line_count = 1 git ls-files -s B/stuff &&
+		test_stdout_line_count = 1 git ls-files -s D/file2 &&
+
+		grep "CONFLICT (implicit dir rename).*Existing file/dir at A/file1 in the way" out &&
+		test_stdout_line_count = 1 git ls-files -s C/file1
+	)
+'
+
+# Testcase 12p, Directory rename hits other rename source; file still in way on other side
+#   Commit O:  A/file1_1
+#              A/stuff
+#              B/file1_2
+#              B/stuff
+#              C/other
+#   Commit A:  D/file2_1
+#              A/stuff
+#              B/stuff
+#              C/file1_2
+#              C/other
+#   Commit B:  A/file1_1
+#              A/stuff
+#              B/file1_2
+#              B/stuff
+#              A/other
+#   Short version:
+#     A: rename A/file1_1 -> D/file2_1
+#        rename B/file1_2 -> C/file1_2
+#     B: Rename C/ -> A/
+#   Rationale:
+#       A/stuff is unmodified, it shows up in final output
+#       B/stuff is unmodified, it shows up in final output
+#       C/other touched on one side (rename to A), so A/other shows up in output
+#       A/file1 is renamed to D/file2
+#       B/file1 -> C/file1 and even though C/ -> A/, A/file1 is
+#               "in the way" so we don't do the directory rename
+#   Expected:  A/stuff
+#              B/stuff
+#              A/other
+#              D/file2
+#              C/file1
+#              + CONFLICT (implicit dir rename): A/file1 in way of C/file1
+#
+
+test_setup_12p () {
+	git init 12p &&
+	(
+		cd 12p &&
+
+		mkdir -p A B C &&
+		echo 1 >A/file1 &&
+		echo 2 >B/file1 &&
+		echo other >C/other &&
+		echo Astuff >A/stuff &&
+		echo Bstuff >B/stuff &&
+		git add . &&
+		git commit -m "O" &&
+
+		git branch O &&
+		git branch A &&
+		git branch B &&
+
+		git switch A &&
+		mkdir -p D &&
+		git mv A/file1 D/file2 &&
+		git mv B/file1 C/ &&
+		git add . &&
+		git commit -m "A" &&
+
+		git switch B &&
+		git mv C/other A/other &&
+		git add . &&
+		git commit -m "B"
+	)
+}
+
+test_expect_success '12p: Directory rename hits other rename source; file still in way on other side' '
+	test_setup_12p &&
+	(
+		cd 12p &&
+
+		git checkout -q A^0 &&
+
+		test_must_fail git -c merge.directoryRenames=conflict merge -s recursive B^0 >out &&
+
+		test_stdout_line_count = 5 git ls-files -s &&
+		test_stdout_line_count = 1 git ls-files -s A/other &&
+		test_stdout_line_count = 1 git ls-files -s A/stuff &&
+		test_stdout_line_count = 1 git ls-files -s B/stuff &&
+		test_stdout_line_count = 1 git ls-files -s D/file2 &&
+
+		grep "CONFLICT (implicit dir rename).*Existing file/dir at A/file1 in the way" out &&
+		test_stdout_line_count = 1 git ls-files -s C/file1
+	)
+'
+
+# Testcase 12q, Directory rename hits other rename source; file removed though
+#   Commit O:  A/file1_1
+#              A/stuff
+#              B/file1_2
+#              B/stuff
+#              C/other
+#   Commit A:  A/stuff
+#              B/stuff
+#              C/file1_2
+#              C/other
+#   Commit B:  D/file2_1
+#              A/stuff
+#              B/file1_2
+#              B/stuff
+#              A/other
+#   In words:
+#     A: delete A/file1_1, rename B/file1_2 -> C/file1_2
+#     B: Rename C/ -> A/, rename A/file1_1 -> D/file2_1
+#   Rationale:
+#       A/stuff is unmodified, it shows up in final output
+#       B/stuff is unmodified, it shows up in final output
+#       C/other touched on one side (rename to A), so A/other shows up in output
+#       A/file1 is rename/delete to D/file2, so two stages for D/file2
+#       B/file1 -> C/file1 and even though C/ -> A/, A/file1 as a source was
+#               "in the way" (ish) so we don't do the directory rename
+#   Expected:  A/stuff
+#              B/stuff
+#              A/other
+#              D/file2 (two stages)
+#              C/file1
+#              + CONFLICT (implicit dir rename): A/file1 in way of C/file1
+#              + CONFLICT (rename/delete): D/file2
+#
+
+test_setup_12q () {
+	git init 12q &&
+	(
+		cd 12q &&
+
+		mkdir -p A B C &&
+		echo 1 >A/file1 &&
+		echo 2 >B/file1 &&
+		echo other >C/other &&
+		echo Astuff >A/stuff &&
+		echo Bstuff >B/stuff &&
+		git add . &&
+		git commit -m "O" &&
+
+		git branch O &&
+		git branch A &&
+		git branch B &&
+
+		git switch A &&
+		git rm A/file1 &&
+		git mv B/file1 C/ &&
+		git add . &&
+		git commit -m "A" &&
+
+		git switch B &&
+		mkdir -p D &&
+		git mv A/file1 D/file2 &&
+		git mv C/other A/other &&
+		git add . &&
+		git commit -m "B"
+	)
+}
+
+test_expect_success '12q: Directory rename hits other rename source; file removed though' '
+	test_setup_12q &&
+	(
+		cd 12q &&
+
+		git checkout -q A^0 &&
+
+		test_must_fail git -c merge.directoryRenames=conflict merge -s recursive B^0 >out &&
+
+		grep "CONFLICT (rename/delete).*A/file1.*D/file2" out &&
+		grep "CONFLICT (implicit dir rename).*Existing file/dir at A/file1 in the way" out &&
+
+		test_stdout_line_count = 6 git ls-files -s &&
+		test_stdout_line_count = 1 git ls-files -s A/other &&
+		test_stdout_line_count = 1 git ls-files -s A/stuff &&
+		test_stdout_line_count = 1 git ls-files -s B/stuff &&
+		test_stdout_line_count = 2 git ls-files -s D/file2 &&
+
+		# This is a slightly suboptimal resolution; allowing the
+		# rename of C/ -> A/ to affect C/file1 and further rename
+		# it to A/file1 would probably be preferable, but since
+		# A/file1 existed as the source of another rename, allowing
+		# the dir rename of C/file1 -> A/file1 would mean modifying
+		# the code so that renames do not adjust both their source
+		# and target paths in all cases.
+		! grep "CONFLICT (file location)" out &&
+		test_stdout_line_count = 1 git ls-files -s C/file1
+	)
+'
 
 ###########################################################################
 # SECTION 13: Checking informational and conflict messages
diff --git a/t/unit-tests/u-string-list.c b/t/unit-tests/u-string-list.c
index d4ba5f9fa52aa2..a2457d7b1ec8fa 100644
--- a/t/unit-tests/u-string-list.c
+++ b/t/unit-tests/u-string-list.c
@@ -43,7 +43,7 @@ static void t_string_list_equal(struct string_list *list,
 				  expected_strings->items[i].string);
 }
 
-static void t_string_list_split(const char *data, int delim, int maxsplit, ...)
+static void t_string_list_split(const char *data, const char *delim, int maxsplit, ...)
 {
 	struct string_list expected_strings = STRING_LIST_INIT_DUP;
 	struct string_list list = STRING_LIST_INIT_DUP;
@@ -63,15 +63,94 @@ static void t_string_list_split(const char *data, int delim, int maxsplit, ...)
 	string_list_clear(&list, 0);
 }
 
+static void t_string_list_split_f(const char *data, const char *delim,
+				  int maxsplit, unsigned flags, ...)
+{
+	struct string_list expected_strings = STRING_LIST_INIT_DUP;
+	struct string_list list = STRING_LIST_INIT_DUP;
+	va_list ap;
+	int len;
+
+	va_start(ap, flags);
+	t_vcreate_string_list_dup(&expected_strings, 0, ap);
+	va_end(ap);
+
+	string_list_clear(&list, 0);
+	len = string_list_split_f(&list, data, delim, maxsplit, flags);
+	cl_assert_equal_i(len, expected_strings.nr);
+	t_string_list_equal(&list, &expected_strings);
+
+	string_list_clear(&expected_strings, 0);
+	string_list_clear(&list, 0);
+}
+
+void test_string_list__split_f(void)
+{
+	t_string_list_split_f("::foo:bar:baz:", ":", -1, 0,
+			      "", "", "foo", "bar", "baz", "", NULL);
+	t_string_list_split_f(" foo:bar : baz", ":", -1, STRING_LIST_SPLIT_TRIM,
+			      "foo", "bar", "baz", NULL);
+	t_string_list_split_f("  a  b c  ", " ", 1, STRING_LIST_SPLIT_TRIM,
+			      "a", "b c", NULL);
+	t_string_list_split_f("::foo::bar:baz:", ":", -1, STRING_LIST_SPLIT_NONEMPTY,
+			      "foo", "bar", "baz", NULL);
+	t_string_list_split_f("foo:baz", ":", -1, STRING_LIST_SPLIT_NONEMPTY,
+			      "foo", "baz", NULL);
+	t_string_list_split_f("foo :: : baz", ":", -1,
+			      STRING_LIST_SPLIT_NONEMPTY | STRING_LIST_SPLIT_TRIM,
+			      "foo", "baz", NULL);
+}
+
+static void t_string_list_split_in_place_f(const char *data_, const char *delim,
+					   int maxsplit, unsigned flags, ...)
+{
+	struct string_list expected_strings = STRING_LIST_INIT_DUP;
+	struct string_list list = STRING_LIST_INIT_NODUP;
+	char *data = xstrdup(data_);
+	va_list ap;
+	int len;
+
+	va_start(ap, flags);
+	t_vcreate_string_list_dup(&expected_strings, 0, ap);
+	va_end(ap);
+
+	string_list_clear(&list, 0);
+	len = string_list_split_in_place_f(&list, data, delim, maxsplit, flags);
+	cl_assert_equal_i(len, expected_strings.nr);
+	t_string_list_equal(&list, &expected_strings);
+
+	free(data);
+	string_list_clear(&expected_strings, 0);
+	string_list_clear(&list, 0);
+}
+
+void test_string_list__split_in_place_f(void)
+{
+	t_string_list_split_in_place_f("::foo:bar:baz:", ":", -1, 0,
+				       "", "", "foo", "bar", "baz", "", NULL);
+	t_string_list_split_in_place_f(" foo:bar : baz", ":", -1, STRING_LIST_SPLIT_TRIM,
+				       "foo", "bar", "baz", NULL);
+	t_string_list_split_in_place_f("  a  b c  ", " ", 1, STRING_LIST_SPLIT_TRIM,
+				       "a", "b c", NULL);
+	t_string_list_split_in_place_f("::foo::bar:baz:", ":", -1,
+				       STRING_LIST_SPLIT_NONEMPTY,
+				       "foo", "bar", "baz", NULL);
+	t_string_list_split_in_place_f("foo:baz", ":", -1, STRING_LIST_SPLIT_NONEMPTY,
+				       "foo", "baz", NULL);
+	t_string_list_split_in_place_f("foo :: : baz", ":", -1,
+				       STRING_LIST_SPLIT_NONEMPTY | STRING_LIST_SPLIT_TRIM,
+				       "foo", "baz", NULL);
+}
+
 void test_string_list__split(void)
 {
-	t_string_list_split("foo:bar:baz", ':', -1, "foo", "bar", "baz", NULL);
-	t_string_list_split("foo:bar:baz", ':', 0, "foo:bar:baz", NULL);
-	t_string_list_split("foo:bar:baz", ':', 1, "foo", "bar:baz", NULL);
-	t_string_list_split("foo:bar:baz", ':', 2, "foo", "bar", "baz", NULL);
-	t_string_list_split("foo:bar:", ':', -1, "foo", "bar", "", NULL);
-	t_string_list_split("", ':', -1, "", NULL);
-	t_string_list_split(":", ':', -1, "", "", NULL);
+	t_string_list_split("foo:bar:baz", ":", -1, "foo", "bar", "baz", NULL);
+	t_string_list_split("foo:bar:baz", ":", 0, "foo:bar:baz", NULL);
+	t_string_list_split("foo:bar:baz", ":", 1, "foo", "bar:baz", NULL);
+	t_string_list_split("foo:bar:baz", ":", 2, "foo", "bar", "baz", NULL);
+	t_string_list_split("foo:bar:", ":", -1, "foo", "bar", "", NULL);
+	t_string_list_split("", ":", -1, "", NULL);
+	t_string_list_split(":", ":", -1, "", "", NULL);
 }
 
 static void t_string_list_split_in_place(const char *data, const char *delim,
diff --git a/trace2/tr2_cfg.c b/trace2/tr2_cfg.c
index 22a99a0682a498..bbcfeda60af4de 100644
--- a/trace2/tr2_cfg.c
+++ b/trace2/tr2_cfg.c
@@ -8,89 +8,65 @@
 #include "trace2/tr2_sysenv.h"
 #include "wildmatch.h"
 
-static struct strbuf **tr2_cfg_patterns;
-static int tr2_cfg_count_patterns;
+static struct string_list tr2_cfg_patterns = STRING_LIST_INIT_DUP;
 static int tr2_cfg_loaded;
 
-static struct strbuf **tr2_cfg_env_vars;
-static int tr2_cfg_env_vars_count;
+static struct string_list tr2_cfg_env_vars = STRING_LIST_INIT_DUP;
 static int tr2_cfg_env_vars_loaded;
 
 /*
  * Parse a string containing a comma-delimited list of config keys
- * or wildcard patterns into a list of strbufs.
+ * or wildcard patterns into a string list.
  */
-static int tr2_cfg_load_patterns(void)
+static size_t tr2_cfg_load_patterns(void)
 {
-	struct strbuf **s;
 	const char *envvar;
 
 	if (tr2_cfg_loaded)
-		return tr2_cfg_count_patterns;
+		return tr2_cfg_patterns.nr;
 	tr2_cfg_loaded = 1;
 
 	envvar = tr2_sysenv_get(TR2_SYSENV_CFG_PARAM);
 	if (!envvar || !*envvar)
-		return tr2_cfg_count_patterns;
+		return tr2_cfg_patterns.nr;
 
-	tr2_cfg_patterns = strbuf_split_buf(envvar, strlen(envvar), ',', -1);
-	for (s = tr2_cfg_patterns; *s; s++) {
-		struct strbuf *buf = *s;
-
-		if (buf->len && buf->buf[buf->len - 1] == ',')
-			strbuf_setlen(buf, buf->len - 1);
-		strbuf_trim_trailing_newline(*s);
-		strbuf_trim(*s);
-	}
-
-	tr2_cfg_count_patterns = s - tr2_cfg_patterns;
-	return tr2_cfg_count_patterns;
+	string_list_split_f(&tr2_cfg_patterns, envvar, ",", -1,
+			    STRING_LIST_SPLIT_TRIM);
+	return tr2_cfg_patterns.nr;
 }
 
 void tr2_cfg_free_patterns(void)
 {
-	if (tr2_cfg_patterns)
-		strbuf_list_free(tr2_cfg_patterns);
-	tr2_cfg_count_patterns = 0;
+	if (tr2_cfg_patterns.nr)
+		string_list_clear(&tr2_cfg_patterns, 0);
 	tr2_cfg_loaded = 0;
 }
 
 /*
  * Parse a string containing a comma-delimited list of environment variable
- * names into a list of strbufs.
+ * names into a string list.
  */
-static int tr2_load_env_vars(void)
+static size_t tr2_load_env_vars(void)
 {
-	struct strbuf **s;
 	const char *varlist;
 
 	if (tr2_cfg_env_vars_loaded)
-		return tr2_cfg_env_vars_count;
+		return tr2_cfg_env_vars.nr;
 	tr2_cfg_env_vars_loaded = 1;
 
 	varlist = tr2_sysenv_get(TR2_SYSENV_ENV_VARS);
 	if (!varlist || !*varlist)
-		return tr2_cfg_env_vars_count;
-
-	tr2_cfg_env_vars = strbuf_split_buf(varlist, strlen(varlist), ',', -1);
-	for (s = tr2_cfg_env_vars; *s; s++) {
-		struct strbuf *buf = *s;
-
-		if (buf->len && buf->buf[buf->len - 1] == ',')
-			strbuf_setlen(buf, buf->len - 1);
-		strbuf_trim_trailing_newline(*s);
-		strbuf_trim(*s);
-	}
+		return tr2_cfg_env_vars.nr;
 
-	tr2_cfg_env_vars_count = s - tr2_cfg_env_vars;
-	return tr2_cfg_env_vars_count;
+	string_list_split_f(&tr2_cfg_env_vars, varlist, ",", -1,
+			    STRING_LIST_SPLIT_TRIM);
+	return tr2_cfg_env_vars.nr;
 }
 
 void tr2_cfg_free_env_vars(void)
 {
-	if (tr2_cfg_env_vars)
-		strbuf_list_free(tr2_cfg_env_vars);
-	tr2_cfg_env_vars_count = 0;
+	if (tr2_cfg_env_vars.nr)
+		string_list_clear(&tr2_cfg_env_vars, 0);
 	tr2_cfg_env_vars_loaded = 0;
 }
 
@@ -105,12 +81,11 @@ struct tr2_cfg_data {
 static int tr2_cfg_cb(const char *key, const char *value,
 		      const struct config_context *ctx, void *d)
 {
-	struct strbuf **s;
+	struct string_list_item *item;
 	struct tr2_cfg_data *data = (struct tr2_cfg_data *)d;
 
-	for (s = tr2_cfg_patterns; *s; s++) {
-		struct strbuf *buf = *s;
-		int wm = wildmatch(buf->buf, key, WM_CASEFOLD);
+	for_each_string_list_item(item, &tr2_cfg_patterns) {
+		int wm = wildmatch(item->string, key, WM_CASEFOLD);
 		if (wm == WM_MATCH) {
 			trace2_def_param_fl(data->file, data->line, key, value,
 					    ctx->kvi);
@@ -132,17 +107,16 @@ void tr2_cfg_list_config_fl(const char *file, int line)
 void tr2_list_env_vars_fl(const char *file, int line)
 {
 	struct key_value_info kvi = KVI_INIT;
-	struct strbuf **s;
+	struct string_list_item *item;
 
 	kvi_from_param(&kvi);
 	if (tr2_load_env_vars() <= 0)
 		return;
 
-	for (s = tr2_cfg_env_vars; *s; s++) {
-		struct strbuf *buf = *s;
-		const char *val = getenv(buf->buf);
+	for_each_string_list_item(item, &tr2_cfg_env_vars) {
+		const char *val = getenv(item->string);
 		if (val && *val)
-			trace2_def_param_fl(file, line, buf->buf, val, &kvi);
+			trace2_def_param_fl(file, line, item->string, val, &kvi);
 	}
 }
 
diff --git a/transport.c b/transport.c
index e305d6bd228b45..6ac8aa402bebfa 100644
--- a/transport.c
+++ b/transport.c
@@ -1042,7 +1042,7 @@ static const struct string_list *protocol_allow_list(void)
 	if (enabled < 0) {
 		const char *v = getenv("GIT_ALLOW_PROTOCOL");
 		if (v) {
-			string_list_split(&allowed, v, ':', -1);
+			string_list_split(&allowed, v, ":", -1);
 			string_list_sort(&allowed);
 			enabled = 1;
 		} else {
diff --git a/upload-pack.c b/upload-pack.c
index 4f26f6afc77106..91fcdcad9b5b48 100644
--- a/upload-pack.c
+++ b/upload-pack.c
@@ -1685,7 +1685,7 @@ static void process_args(struct packet_reader *request,
 			if (data->uri_protocols.nr)
 				send_err_and_die(data,
 						 "multiple packfile-uris lines forbidden");
-			string_list_split(&data->uri_protocols, p, ',', -1);
+			string_list_split(&data->uri_protocols, p, ",", -1);
 			continue;
 		}
 
diff --git a/wt-status.c b/wt-status.c
index 454601afa15a95..21dabab77d7096 100644
--- a/wt-status.c
+++ b/wt-status.c
@@ -972,7 +972,8 @@ static void wt_longstatus_print_changed(struct wt_status *s)
 	wt_longstatus_print_trailer(s);
 }
 
-static int stash_count_refs(struct object_id *ooid UNUSED,
+static int stash_count_refs(const char *refname UNUSED,
+			    struct object_id *ooid UNUSED,
 			    struct object_id *noid UNUSED,
 			    const char *email UNUSED,
 			    timestamp_t timestamp UNUSED, int tz UNUSED,
@@ -1351,8 +1352,8 @@ static int split_commit_in_progress(struct wt_status *s)
  */
 static void abbrev_oid_in_line(struct strbuf *line)
 {
-	struct strbuf **split;
-	int i;
+	struct string_list split = STRING_LIST_INIT_DUP;
+	struct object_id oid;
 
 	if (starts_with(line->buf, "exec ") ||
 	    starts_with(line->buf, "x ") ||
@@ -1360,26 +1361,15 @@ static void abbrev_oid_in_line(struct strbuf *line)
 	    starts_with(line->buf, "l "))
 		return;
 
-	split = strbuf_split_max(line, ' ', 3);
-	if (split[0] && split[1]) {
-		struct object_id oid;
-
-		/*
-		 * strbuf_split_max left a space. Trim it and re-add
-		 * it after abbreviation.
-		 */
-		strbuf_trim(split[1]);
-		if (!repo_get_oid(the_repository, split[1]->buf, &oid)) {
-			strbuf_reset(split[1]);
-			strbuf_add_unique_abbrev(split[1], &oid,
-						 DEFAULT_ABBREV);
-			strbuf_addch(split[1], ' ');
-			strbuf_reset(line);
-			for (i = 0; split[i]; i++)
-				strbuf_addbuf(line, split[i]);
-		}
+	if ((2 <= string_list_split(&split, line->buf, " ", 2)) &&
+	    !repo_get_oid(the_repository, split.items[1].string, &oid)) {
+		strbuf_reset(line);
+		strbuf_addf(line, "%s ", split.items[0].string);
+		strbuf_add_unique_abbrev(line, &oid, DEFAULT_ABBREV);
+		for (size_t i = 2; i < split.nr; i++)
+			strbuf_addf(line, " %s", split.items[i].string);
 	}
-	strbuf_list_free(split);
+	string_list_clear(&split, 0);
 }
 
 static int read_rebase_todolist(const char *fname, struct string_list *lines)
@@ -1664,7 +1654,8 @@ struct grab_1st_switch_cbdata {
 	struct object_id noid;
 };
 
-static int grab_1st_switch(struct object_id *ooid UNUSED,
+static int grab_1st_switch(const char *refname UNUSED,
+			   struct object_id *ooid UNUSED,
 			   struct object_id *noid,
 			   const char *email UNUSED,
 			   timestamp_t timestamp UNUSED, int tz UNUSED,