Merge branch 'jl/remote-rm-prune' into maint

"git remote rm" and "git remote prune" can involve removing many
refs at once, which is not a very efficient thing to do when very
many refs exist in the packed-refs file.

* jl/remote-rm-prune:
  remote prune: optimize "dangling symref" check/warning
  remote: repack packed-refs once when deleting multiple refs
  remote rm: delete remote configuration as the last

builtin/remote.c

@@ -749,15 +749,23 @@ static int mv(int argc, const char **argv)
 
 static int remove_branches(struct string_list *branches)
 {
+	const char **branch_names;
 	int i, result = 0;
+
+	branch_names = xmalloc(branches->nr * sizeof(*branch_names));
+	for (i = 0; i < branches->nr; i++)
+		branch_names[i] = branches->items[i].string;
+	result |= repack_without_refs(branch_names, branches->nr);
+	free(branch_names);
+
 	for (i = 0; i < branches->nr; i++) {
 		struct string_list_item *item = branches->items + i;
 		const char *refname = item->string;
-		unsigned char *sha1 = item->util;
 
-		if (delete_ref(refname, sha1, 0))
+		if (delete_ref(refname, NULL, 0))
 			result |= error(_("Could not remove branch %s"), refname);
 	}
+
 	return result;
 }
 
@@ -789,10 +797,6 @@ static int rm(int argc, const char **argv)
 	known_remotes.to_delete = remote;
 	for_each_remote(add_known_remote, &known_remotes);
 
-	strbuf_addf(&buf, "remote.%s", remote->name);
-	if (git_config_rename_section(buf.buf, NULL) < 1)
-		return error(_("Could not remove config section '%s'"), buf.buf);
-
 	read_branches();
 	for (i = 0; i < branch_list.nr; i++) {
 		struct string_list_item *item = branch_list.items + i;
@@ -837,6 +841,12 @@ static int rm(int argc, const char **argv)
 	}
 	string_list_clear(&skipped, 0);
 
+	if (!result) {
+		strbuf_addf(&buf, "remote.%s", remote->name);
+		if (git_config_rename_section(buf.buf, NULL) < 1)
+			return error(_("Could not remove config section '%s'"), buf.buf);
+	}
+
 	return result;
 }
 
@@ -1303,6 +1313,8 @@ static int prune_remote(const char *remote, int dry_run)
 {
 	int result = 0, i;
 	struct ref_states states;
+	struct string_list delete_refs_list = STRING_LIST_INIT_NODUP;
+	const char **delete_refs;
 	const char *dangling_msg = dry_run
 		? _(" %s will become dangling!")
 		: _(" %s has become dangling!");
@@ -1316,11 +1328,20 @@ static int prune_remote(const char *remote, int dry_run)
 		       states.remote->url_nr
 		       ? states.remote->url[0]
 		       : _("(no URL)"));
+
+		delete_refs = xmalloc(states.stale.nr * sizeof(*delete_refs));
+		for (i = 0; i < states.stale.nr; i++)
+			delete_refs[i] = states.stale.items[i].util;
+		if (!dry_run)
+			result |= repack_without_refs(delete_refs, states.stale.nr);
+		free(delete_refs);
 	}
 
 	for (i = 0; i < states.stale.nr; i++) {
 		const char *refname = states.stale.items[i].util;
 
+		string_list_insert(&delete_refs_list, refname);
+
 		if (!dry_run)
 			result |= delete_ref(refname, NULL, 0);
 
@@ -1330,9 +1351,11 @@ static int prune_remote(const char *remote, int dry_run)
 		else
 			printf_ln(_(" * [pruned] %s"),
 			       abbrev_ref(refname, "refs/remotes/"));
-		warn_dangling_symref(stdout, dangling_msg, refname);
 	}
 
+	warn_dangling_symrefs(stdout, dangling_msg, &delete_refs_list);
+	string_list_clear(&delete_refs_list, 0);
+
 	free_remote_ref_states(&states);
 	return result;
 }

refs.c

@@ -1611,6 +1611,7 @@ int peel_ref(const char *refname, unsigned char *sha1)
 struct warn_if_dangling_data {
 	FILE *fp;
 	const char *refname;
+	const struct string_list *refnames;
 	const char *msg_fmt;
 };
 
@@ -1625,8 +1626,12 @@ static int warn_if_dangling_symref(const char *refname, const unsigned char *sha
 		return 0;
 
 	resolves_to = resolve_ref_unsafe(refname, junk, 0, NULL);
-	if (!resolves_to || strcmp(resolves_to, d->refname))
+	if (!resolves_to
+	    || (d->refname
+		? strcmp(resolves_to, d->refname)
+		: !string_list_has_string(d->refnames, resolves_to))) {
 		return 0;
+	}
 
 	fprintf(d->fp, d->msg_fmt, refname);
 	fputc('\n', d->fp);
@@ -1639,6 +1644,18 @@ void warn_dangling_symref(FILE *fp, const char *msg_fmt, const char *refname)
 
 	data.fp = fp;
 	data.refname = refname;
+	data.refnames = NULL;
+	data.msg_fmt = msg_fmt;
+	for_each_rawref(warn_if_dangling_symref, &data);
+}
+
+void warn_dangling_symrefs(FILE *fp, const char *msg_fmt, const struct string_list *refnames)
+{
+	struct warn_if_dangling_data data;
+
+	data.fp = fp;
+	data.refname = NULL;
+	data.refnames = refnames;
 	data.msg_fmt = msg_fmt;
 	for_each_rawref(warn_if_dangling_symref, &data);
 }
@@ -2431,7 +2448,7 @@ static int curate_packed_ref_fn(struct ref_entry *entry, void *cb_data)
 	return 0;
 }
 
-static int repack_without_refs(const char **refnames, int n)
+int repack_without_refs(const char **refnames, int n)
 {
 	struct ref_dir *packed;
 	struct string_list refs_to_delete = STRING_LIST_INIT_DUP;

refs.h

@@ -89,6 +89,7 @@ static inline const char *has_glob_specials(const char *pattern)
 extern int for_each_rawref(each_ref_fn, void *);
 
 extern void warn_dangling_symref(FILE *fp, const char *msg_fmt, const char *refname);
+extern void warn_dangling_symrefs(FILE *fp, const char *msg_fmt, const struct string_list* refnames);
 
 /*
  * Lock the packed-refs file for writing.  Flags is passed to
@@ -132,6 +133,8 @@ extern void rollback_packed_refs(void);
  */
 int pack_refs(unsigned int flags);
 
+extern int repack_without_refs(const char **refnames, int n);
+
 extern int ref_exists(const char *);
 
 /*