Merge branch 'kn/for-each-tag'

The "ref-filter" code was taught about many parts of what "tag -l"
does and then "tag -l" is being reimplemented in terms of "ref-filter".

* kn/for-each-tag:
  tag.c: implement '--merged' and '--no-merged' options
  tag.c: implement '--format' option
  tag.c: use 'ref-filter' APIs
  tag.c: use 'ref-filter' data structures
  ref-filter: add option to match literal pattern
  ref-filter: add support to sort by version
  ref-filter: add support for %(contents:lines=X)
  ref-filter: add option to filter out tags, branches and remotes
  ref-filter: implement an `align` atom
  ref-filter: introduce match_atom_name()
  ref-filter: introduce handler function for each atom
  utf8: add function to align a string into given strbuf
  ref-filter: introduce ref_formatting_state and ref_formatting_stack
  ref-filter: move `struct atom_value` to ref-filter.c
  strtoul_ui: reject negative values

13 files changed, 746 insertions, 379 deletions

diff --git a/Documentation/git-for-each-ref.txt b/Documentation/git-for-each-ref.txt
index d6a1abcca5..c6f073cea4 100644
--- a/Documentation/git-for-each-ref.txt
+++ b/Documentation/git-for-each-ref.txt
@@ -127,6 +127,17 @@ color::
 	Change output color.  Followed by `:<colorname>`, where names
 	are described in `color.branch.*`.
 
+align::
+	Left-, middle-, or right-align the content between
+	%(align:...) and %(end). The "align:" is followed by `<width>`
+	and `<position>` in any order separated by a comma, where the
+	`<position>` is either left, right or middle, default being
+	left and `<width>` is the total length of the content with
+	alignment. If the contents length is more than the width then
+	no alignment is performed. If used with '--quote' everything
+	in between %(align:...) and %(end) is quoted, but if nested
+	then only the topmost level performs quoting.
+
 In addition to the above, for commit and tag objects, the header
 field names (`tree`, `parent`, `object`, `type`, and `tag`) can
 be used to specify the value in the header field.
@@ -139,12 +150,16 @@ The complete message in a commit and tag object is `contents`.
 Its first line is `contents:subject`, where subject is the concatenation
 of all lines of the commit message up to the first blank line.  The next
 line is 'contents:body', where body is all of the lines after the first
-blank line.  Finally, the optional GPG signature is `contents:signature`.
+blank line.  The optional GPG signature is `contents:signature`.  The
+first `N` lines of the message is obtained using `contents:lines=N`.
 
 For sorting purposes, fields with numeric values sort in numeric
 order (`objectsize`, `authordate`, `committerdate`, `taggerdate`).
 All other fields are used to sort in their byte-value order.
 
+There is also an option to sort by versions, this can be done by using
+the fieldname `version:refname` or its alias `v:refname`.
+
 In any case, a field name that refers to a field inapplicable to
 the object referred by the ref does not cause an error.  It
 returns an empty string instead.
diff --git a/Documentation/git-tag.txt b/Documentation/git-tag.txt
index 84f6496bf2..3803bf7fb9 100644
--- a/Documentation/git-tag.txt
+++ b/Documentation/git-tag.txt
@@ -13,7 +13,8 @@ SYNOPSIS
 	<tagname> [<commit> | <object>]
 'git tag' -d <tagname>...
 'git tag' [-n[<num>]] -l [--contains <commit>] [--points-at <object>]
-	[--column[=<options>] | --no-column] [--create-reflog] [<pattern>...]
+	[--column[=<options>] | --no-column] [--create-reflog] [--sort=<key>]
+	[--format=<format>] [--[no-]merged [<commit>]] [<pattern>...]
 'git tag' -v <tagname>...
 
 DESCRIPTION
@@ -94,14 +95,16 @@ OPTIONS
 	using fnmatch(3)).  Multiple patterns may be given; if any of
 	them matches, the tag is shown.
 
---sort=<type>::
-	Sort in a specific order. Supported type is "refname"
-	(lexicographic order), "version:refname" or "v:refname" (tag
+--sort=<key>::
+	Sort based on the key given.  Prefix `-` to sort in
+	descending order of the value. You may use the --sort=<key> option
+	multiple times, in which case the last key becomes the primary
+	key. Also supports "version:refname" or "v:refname" (tag
 	names are treated as versions). The "version:refname" sort
 	order can also be affected by the
-	"versionsort.prereleaseSuffix" configuration variable. Prepend
-	"-" to reverse sort order. When this option is not given, the
-	sort order defaults to the value configured for the 'tag.sort'
+	"versionsort.prereleaseSuffix" configuration variable.
+	The keys supported are the same as those in `git for-each-ref`.
+	Sort order defaults to the value configured for the 'tag.sort'
 	variable if it exists, or lexicographic order otherwise. See
 	linkgit:git-config[1].
 
@@ -156,6 +159,16 @@ This option is only applicable when listing tags without annotation lines.
 	The object that the new tag will refer to, usually a commit.
 	Defaults to HEAD.
 
+<format>::
+	A string that interpolates `%(fieldname)` from the object
+	pointed at by a ref being shown.  The format is the same as
+	that of linkgit:git-for-each-ref[1].  When unspecified,
+	defaults to `%(refname:short)`.
+
+--[no-]merged [<commit>]::
+	Only list tags whose tips are reachable, or not reachable
+	if '--no-merged' is used, from the specified commit ('HEAD'
+	if not specified).
 
 CONFIGURATION
 -------------
diff --git a/builtin/for-each-ref.c b/builtin/for-each-ref.c
index 40f343b6a3..4e9f6c29bf 100644
--- a/builtin/for-each-ref.c
+++ b/builtin/for-each-ref.c
@@ -68,6 +68,7 @@ int cmd_for_each_ref(int argc, const char **argv, const char *prefix)
 	git_config(git_default_config, NULL);
 
 	filter.name_patterns = argv;
+	filter.match_as_path = 1;
 	filter_refs(&array, &filter, FILTER_REFS_ALL | FILTER_REFS_INCLUDE_BROKEN);
 	ref_array_sort(sorting, &array);
 
diff --git a/builtin/tag.c b/builtin/tag.c
index aaae358c2e..9e17dca7ca 100644
--- a/builtin/tag.c
+++ b/builtin/tag.c
@@ -17,280 +17,49 @@
 #include "gpg-interface.h"
 #include "sha1-array.h"
 #include "column.h"
+#include "ref-filter.h"
 
 static const char * const git_tag_usage[] = {
 	N_("git tag [-a | -s | -u <key-id>] [-f] [-m <msg> | -F <file>] <tagname> [<head>]"),
 	N_("git tag -d <tagname>..."),
 	N_("git tag -l [-n[<num>]] [--contains <commit>] [--points-at <object>]"
-		"\n\t\t[<pattern>...]"),
+		"\n\t\t[--format=<format>] [--[no-]merged [<commit>]] [<pattern>...]"),
 	N_("git tag -v <tagname>..."),
 	NULL
 };
 
-#define STRCMP_SORT     0	/* must be zero */
-#define VERCMP_SORT     1
-#define SORT_MASK       0x7fff
-#define REVERSE_SORT    0x8000
-
-static int tag_sort;
-
-struct tag_filter {
-	const char **patterns;
-	int lines;
-	int sort;
-	struct string_list tags;
-	struct commit_list *with_commit;
-};
-
-static struct sha1_array points_at;
 static unsigned int colopts;
 
-static int match_pattern(const char **patterns, const char *ref)
-{
-	/* no pattern means match everything */
-	if (!*patterns)
-		return 1;
-	for (; *patterns; patterns++)
-		if (!wildmatch(*patterns, ref, 0, NULL))
-			return 1;
-	return 0;
-}
-
-/*
- * This is currently duplicated in ref-filter.c, and will eventually be
- * removed as we port tag.c to use the ref-filter APIs.
- */
-static const unsigned char *match_points_at(const char *refname,
-					    const unsigned char *sha1)
-{
-	const unsigned char *tagged_sha1 = NULL;
-	struct object *obj;
-
-	if (sha1_array_lookup(&points_at, sha1) >= 0)
-		return sha1;
-	obj = parse_object(sha1);
-	if (!obj)
-		die(_("malformed object at '%s'"), refname);
-	if (obj->type == OBJ_TAG)
-		tagged_sha1 = ((struct tag *)obj)->tagged->sha1;
-	if (tagged_sha1 && sha1_array_lookup(&points_at, tagged_sha1) >= 0)
-		return tagged_sha1;
-	return NULL;
-}
-
-static int in_commit_list(const struct commit_list *want, struct commit *c)
-{
-	for (; want; want = want->next)
-		if (!hashcmp(want->item->object.sha1, c->object.sha1))
-			return 1;
-	return 0;
-}
-
-/*
- * The entire code segment for supporting the --contains option has been
- * copied over to ref-filter.{c,h}. This will be deleted evetually when
- * we port tag.c to use ref-filter APIs.
- */
-enum contains_result {
-	CONTAINS_UNKNOWN = -1,
-	CONTAINS_NO = 0,
-	CONTAINS_YES = 1
-};
-
-/*
- * Test whether the candidate or one of its parents is contained in the list.
- * Do not recurse to find out, though, but return -1 if inconclusive.
- */
-static enum contains_result contains_test(struct commit *candidate,
-			    const struct commit_list *want)
-{
-	/* was it previously marked as containing a want commit? */
-	if (candidate->object.flags & TMP_MARK)
-		return 1;
-	/* or marked as not possibly containing a want commit? */
-	if (candidate->object.flags & UNINTERESTING)
-		return 0;
-	/* or are we it? */
-	if (in_commit_list(want, candidate)) {
-		candidate->object.flags |= TMP_MARK;
-		return 1;
-	}
-
-	if (parse_commit(candidate) < 0)
-		return 0;
-
-	return -1;
-}
-
-/*
- * Mimicking the real stack, this stack lives on the heap, avoiding stack
- * overflows.
- *
- * At each recursion step, the stack items points to the commits whose
- * ancestors are to be inspected.
- */
-struct stack {
-	int nr, alloc;
-	struct stack_entry {
-		struct commit *commit;
-		struct commit_list *parents;
-	} *stack;
-};
-
-static void push_to_stack(struct commit *candidate, struct stack *stack)
-{
-	int index = stack->nr++;
-	ALLOC_GROW(stack->stack, stack->nr, stack->alloc);
-	stack->stack[index].commit = candidate;
-	stack->stack[index].parents = candidate->parents;
-}
-
-static enum contains_result contains(struct commit *candidate,
-		const struct commit_list *want)
-{
-	struct stack stack = { 0, 0, NULL };
-	int result = contains_test(candidate, want);
-
-	if (result != CONTAINS_UNKNOWN)
-		return result;
-
-	push_to_stack(candidate, &stack);
-	while (stack.nr) {
-		struct stack_entry *entry = &stack.stack[stack.nr - 1];
-		struct commit *commit = entry->commit;
-		struct commit_list *parents = entry->parents;
-
-		if (!parents) {
-			commit->object.flags |= UNINTERESTING;
-			stack.nr--;
-		}
-		/*
-		 * If we just popped the stack, parents->item has been marked,
-		 * therefore contains_test will return a meaningful 0 or 1.
-		 */
-		else switch (contains_test(parents->item, want)) {
-		case CONTAINS_YES:
-			commit->object.flags |= TMP_MARK;
-			stack.nr--;
-			break;
-		case CONTAINS_NO:
-			entry->parents = parents->next;
-			break;
-		case CONTAINS_UNKNOWN:
-			push_to_stack(parents->item, &stack);
-			break;
-		}
-	}
-	free(stack.stack);
-	return contains_test(candidate, want);
-}
-
-static void show_tag_lines(const struct object_id *oid, int lines)
+static int list_tags(struct ref_filter *filter, struct ref_sorting *sorting, const char *format)
 {
+	struct ref_array array;
+	char *to_free = NULL;
 	int i;
-	unsigned long size;
-	enum object_type type;
-	char *buf, *sp, *eol;
-	size_t len;
-
-	buf = read_sha1_file(oid->hash, &type, &size);
-	if (!buf)
-		die_errno("unable to read object %s", oid_to_hex(oid));
-	if (type != OBJ_COMMIT && type != OBJ_TAG)
-		goto free_return;
-	if (!size)
-		die("an empty %s object %s?",
-		    typename(type), oid_to_hex(oid));
-
-	/* skip header */
-	sp = strstr(buf, "\n\n");
-	if (!sp)
-		goto free_return;
-
-	/* only take up to "lines" lines, and strip the signature from a tag */
-	if (type == OBJ_TAG)
-		size = parse_signature(buf, size);
-	for (i = 0, sp += 2; i < lines && sp < buf + size; i++) {
-		if (i)
-			printf("\n    ");
-		eol = memchr(sp, '\n', size - (sp - buf));
-		len = eol ? eol - sp : size - (sp - buf);
-		fwrite(sp, len, 1, stdout);
-		if (!eol)
-			break;
-		sp = eol + 1;
-	}
-free_return:
-	free(buf);
-}
-
-static int show_reference(const char *refname, const struct object_id *oid,
-			  int flag, void *cb_data)
-{
-	struct tag_filter *filter = cb_data;
-
-	if (match_pattern(filter->patterns, refname)) {
-		if (filter->with_commit) {
-			struct commit *commit;
 
-			commit = lookup_commit_reference_gently(oid->hash, 1);
-			if (!commit)
-				return 0;
-			if (!contains(commit, filter->with_commit))
-				return 0;
-		}
+	memset(&array, 0, sizeof(array));
 
-		if (points_at.nr && !match_points_at(refname, oid->hash))
-			return 0;
+	if (filter->lines == -1)
+		filter->lines = 0;
 
-		if (!filter->lines) {
-			if (filter->sort)
-				string_list_append(&filter->tags, refname);
-			else
-				printf("%s\n", refname);
-			return 0;
-		}
-		printf("%-15s ", refname);
-		show_tag_lines(oid, filter->lines);
-		putchar('\n');
+	if (!format) {
+		if (filter->lines) {
+			to_free = xstrfmt("%s %%(contents:lines=%d)",
+					  "%(align:15)%(refname:short)%(end)",
+					  filter->lines);
+			format = to_free;
+		} else
+			format = "%(refname:short)";
 	}
 
-	return 0;
-}
+	verify_ref_format(format);
+	filter_refs(&array, filter, FILTER_REFS_TAGS);
+	ref_array_sort(sorting, &array);
 
-static int sort_by_version(const void *a_, const void *b_)
-{
-	const struct string_list_item *a = a_;
-	const struct string_list_item *b = b_;
-	return versioncmp(a->string, b->string);
-}
+	for (i = 0; i < array.nr; i++)
+		show_ref_array_item(array.items[i], format, 0);
+	ref_array_clear(&array);
+	free(to_free);
 
-static int list_tags(const char **patterns, int lines,
-		     struct commit_list *with_commit, int sort)
-{
-	struct tag_filter filter;
-
-	filter.patterns = patterns;
-	filter.lines = lines;
-	filter.sort = sort;
-	filter.with_commit = with_commit;
-	memset(&filter.tags, 0, sizeof(filter.tags));
-	filter.tags.strdup_strings = 1;
-
-	for_each_tag_ref(show_reference, (void *)&filter);
-	if (sort) {
-		int i;
-		if ((sort & SORT_MASK) == VERCMP_SORT)
-			qsort(filter.tags.items, filter.tags.nr,
-			      sizeof(struct string_list_item), sort_by_version);
-		if (sort & REVERSE_SORT)
-			for (i = filter.tags.nr - 1; i >= 0; i--)
-				printf("%s\n", filter.tags.items[i].string);
-		else
-			for (i = 0; i < filter.tags.nr; i++)
-				printf("%s\n", filter.tags.items[i].string);
-		string_list_clear(&filter.tags, 0);
-	}
 	return 0;
 }
 
@@ -357,35 +126,26 @@ static const char tag_template_nocleanup[] =
 	"Lines starting with '%c' will be kept; you may remove them"
 	" yourself if you want to.\n");
 
-/*
- * Parse a sort string, and return 0 if parsed successfully. Will return
- * non-zero when the sort string does not parse into a known type. If var is
- * given, the error message becomes a warning and includes information about
- * the configuration value.
- */
-static int parse_sort_string(const char *var, const char *arg, int *sort)
+/* Parse arg given and add it the ref_sorting array */
+static int parse_sorting_string(const char *arg, struct ref_sorting **sorting_tail)
 {
-	int type = 0, flags = 0;
+	struct ref_sorting *s;
+	int len;
 
-	if (skip_prefix(arg, "-", &arg))
-		flags |= REVERSE_SORT;
+	s = xcalloc(1, sizeof(*s));
+	s->next = *sorting_tail;
+	*sorting_tail = s;
 
-	if (skip_prefix(arg, "version:", &arg) || skip_prefix(arg, "v:", &arg))
-		type = VERCMP_SORT;
-	else
-		type = STRCMP_SORT;
-
-	if (strcmp(arg, "refname")) {
-		if (!var)
-			return error(_("unsupported sort specification '%s'"), arg);
-		else {
-			warning(_("unsupported sort specification '%s' in variable '%s'"),
-				var, arg);
-			return -1;
-		}
+	if (*arg == '-') {
+		s->reverse = 1;
+		arg++;
 	}
+	if (skip_prefix(arg, "version:", &arg) ||
+	    skip_prefix(arg, "v:", &arg))
+		s->version = 1;
 
-	*sort = (type | flags);
+	len = strlen(arg);
+	s->atom = parse_ref_filter_atom(arg, arg+len);
 
 	return 0;
 }
@@ -393,11 +153,12 @@ static int parse_sort_string(const char *var, const char *arg, int *sort)
 static int git_tag_config(const char *var, const char *value, void *cb)
 {
 	int status;
+	struct ref_sorting **sorting_tail = (struct ref_sorting **)cb;
 
 	if (!strcmp(var, "tag.sort")) {
 		if (!value)
 			return config_error_nonbool(var);
-		parse_sort_string(var, value, &tag_sort);
+		parse_sorting_string(value, sorting_tail);
 		return 0;
 	}
 
@@ -555,13 +316,6 @@ static int strbuf_check_tag_ref(struct strbuf *sb, const char *name)
 	return check_refname_format(sb->buf, 0);
 }
 
-static int parse_opt_sort(const struct option *opt, const char *arg, int unset)
-{
-	int *sort = opt->value;
-
-	return parse_sort_string(NULL, arg, sort);
-}
-
 int cmd_tag(int argc, const char **argv, const char *prefix)
 {
 	struct strbuf buf = STRBUF_INIT;
@@ -570,17 +324,19 @@ int cmd_tag(int argc, const char **argv, const char *prefix)
 	const char *object_ref, *tag;
 	struct create_tag_options opt;
 	char *cleanup_arg = NULL;
-	int annotate = 0, force = 0, lines = -1;
 	int create_reflog = 0;
+	int annotate = 0, force = 0;
 	int cmdmode = 0;
 	const char *msgfile = NULL, *keyid = NULL;
 	struct msg_arg msg = { 0, STRBUF_INIT };
-	struct commit_list *with_commit = NULL;
 	struct ref_transaction *transaction;
 	struct strbuf err = STRBUF_INIT;
+	struct ref_filter filter;
+	static struct ref_sorting *sorting = NULL, **sorting_tail = &sorting;
+	const char *format = NULL;
 	struct option options[] = {
 		OPT_CMDMODE('l', "list", &cmdmode, N_("list tag names"), 'l'),
-		{ OPTION_INTEGER, 'n', NULL, &lines, N_("n"),
+		{ OPTION_INTEGER, 'n', NULL, &filter.lines, N_("n"),
 				N_("print <n> lines of each tag message"),
 				PARSE_OPT_OPTARG, NULL, 1 },
 		OPT_CMDMODE('d', "delete", &cmdmode, N_("delete tags"), 'd'),
@@ -602,22 +358,25 @@ int cmd_tag(int argc, const char **argv, const char *prefix)
 
 		OPT_GROUP(N_("Tag listing options")),
 		OPT_COLUMN(0, "column", &colopts, N_("show tag list in columns")),
-		OPT_CONTAINS(&with_commit, N_("print only tags that contain the commit")),
-		OPT_WITH(&with_commit, N_("print only tags that contain the commit")),
-		{
-			OPTION_CALLBACK, 0, "sort", &tag_sort, N_("type"), N_("sort tags"),
-			PARSE_OPT_NONEG, parse_opt_sort
-		},
+		OPT_CONTAINS(&filter.with_commit, N_("print only tags that contain the commit")),
+		OPT_WITH(&filter.with_commit, N_("print only tags that contain the commit")),
+		OPT_MERGED(&filter, N_("print only tags that are merged")),
+		OPT_NO_MERGED(&filter, N_("print only tags that are not merged")),
+		OPT_CALLBACK(0 , "sort", sorting_tail, N_("key"),
+			     N_("field name to sort on"), &parse_opt_ref_sorting),
 		{
-			OPTION_CALLBACK, 0, "points-at", &points_at, N_("object"),
+			OPTION_CALLBACK, 0, "points-at", &filter.points_at, N_("object"),
 			N_("print only tags of the object"), 0, parse_opt_object_name
 		},
+		OPT_STRING(  0 , "format", &format, N_("format"), N_("format to use for the output")),
 		OPT_END()
 	};
 
-	git_config(git_tag_config, NULL);
+	git_config(git_tag_config, sorting_tail);
 
 	memset(&opt, 0, sizeof(opt));
+	memset(&filter, 0, sizeof(filter));
+	filter.lines = -1;
 
 	argc = parse_options(argc, argv, prefix, options, git_tag_usage, 0);
 
@@ -634,11 +393,13 @@ int cmd_tag(int argc, const char **argv, const char *prefix)
 		usage_with_options(git_tag_usage, options);
 
 	finalize_colopts(&colopts, -1);
-	if (cmdmode == 'l' && lines != -1) {
+	if (cmdmode == 'l' && filter.lines != -1) {
 		if (explicitly_enable_column(colopts))
 			die(_("--column and -n are incompatible"));
 		colopts = 0;
 	}
+	if (!sorting)
+		sorting = ref_default_sorting();
 	if (cmdmode == 'l') {
 		int ret;
 		if (column_active(colopts)) {
@@ -647,19 +408,20 @@ int cmd_tag(int argc, const char **argv, const char *prefix)
 			copts.padding = 2;
 			run_column_filter(colopts, &copts);
 		}
-		if (lines != -1 && tag_sort)
-			die(_("--sort and -n are incompatible"));
-		ret = list_tags(argv, lines == -1 ? 0 : lines, with_commit, tag_sort);
+		filter.name_patterns = argv;
+		ret = list_tags(&filter, sorting, format);
 		if (column_active(colopts))
 			stop_column_filter();
 		return ret;
 	}
-	if (lines != -1)
+	if (filter.lines != -1)
 		die(_("-n option is only allowed with -l."));
-	if (with_commit)
+	if (filter.with_commit)
 		die(_("--contains option is only allowed with -l."));
-	if (points_at.nr)
+	if (filter.points_at.nr)
 		die(_("--points-at option is only allowed with -l."));
+	if (filter.merge_commit)
+		die(_("--merged and --no-merged option are only allowed with -l"));
 	if (cmdmode == 'd')
 		return for_each_tag_name(argv, delete_tag);
 	if (cmdmode == 'v')
diff --git a/git-compat-util.h b/git-compat-util.h
index f649e81f11..1df82fa598 100644
--- a/git-compat-util.h
+++ b/git-compat-util.h
@@ -814,6 +814,9 @@ static inline int strtoul_ui(char const *s, int base, unsigned int *result)
 	char *p;
 
 	errno = 0;
+	/* negative values would be accepted by strtoul */
+	if (strchr(s, '-'))
+		return -1;
 	ul = strtoul(s, &p, base);
 	if (errno || *p || p == s || (unsigned int) ul != ul)
 		return -1;
diff --git a/ref-filter.c b/ref-filter.c
index 46963a5a42..fd839ac4b3 100644
--- a/ref-filter.c
+++ b/ref-filter.c
@@ -10,6 +10,9 @@
 #include "quote.h"
 #include "ref-filter.h"
 #include "revision.h"
+#include "utf8.h"
+#include "git-compat-util.h"
+#include "version.h"
 
 typedef enum { FIELD_STR, FIELD_ULONG, FIELD_TIME } cmp_type;
 
@@ -44,15 +47,48 @@ static struct {
 	{ "subject" },
 	{ "body" },
 	{ "contents" },
-	{ "contents:subject" },
-	{ "contents:body" },
-	{ "contents:signature" },
 	{ "upstream" },
 	{ "push" },
 	{ "symref" },
 	{ "flag" },
 	{ "HEAD" },
 	{ "color" },
+	{ "align" },
+	{ "end" },
+};
+
+#define REF_FORMATTING_STATE_INIT  { 0, NULL }
+
+struct align {
+	align_type position;
+	unsigned int width;
+};
+
+struct contents {
+	unsigned int lines;
+	struct object_id oid;
+};
+
+struct ref_formatting_stack {
+	struct ref_formatting_stack *prev;
+	struct strbuf output;
+	void (*at_end)(struct ref_formatting_stack *stack);
+	void *at_end_data;
+};
+
+struct ref_formatting_state {
+	int quote_style;
+	struct ref_formatting_stack *stack;
+};
+
+struct atom_value {
+	const char *s;
+	union {
+		struct align align;
+		struct contents contents;
+	} u;
+	void (*handler)(struct atom_value *atomv, struct ref_formatting_state *state);
+	unsigned long ul; /* used for sorting when not FIELD_STR */
 };
 
 /*
@@ -124,6 +160,120 @@ int parse_ref_filter_atom(const char *atom, const char *ep)
 	return at;
 }
 
+static void quote_formatting(struct strbuf *s, const char *str, int quote_style)
+{
+	switch (quote_style) {
+	case QUOTE_NONE:
+		strbuf_addstr(s, str);
+		break;
+	case QUOTE_SHELL:
+		sq_quote_buf(s, str);
+		break;
+	case QUOTE_PERL:
+		perl_quote_buf(s, str);
+		break;
+	case QUOTE_PYTHON:
+		python_quote_buf(s, str);
+		break;
+	case QUOTE_TCL:
+		tcl_quote_buf(s, str);
+		break;
+	}
+}
+
+static void append_atom(struct atom_value *v, struct ref_formatting_state *state)
+{
+	/*
+	 * Quote formatting is only done when the stack has a single
+	 * element. Otherwise quote formatting is done on the
+	 * element's entire output strbuf when the %(end) atom is
+	 * encountered.
+	 */
+	if (!state->stack->prev)
+		quote_formatting(&state->stack->output, v->s, state->quote_style);
+	else
+		strbuf_addstr(&state->stack->output, v->s);
+}
+
+static void push_stack_element(struct ref_formatting_stack **stack)
+{
+	struct ref_formatting_stack *s = xcalloc(1, sizeof(struct ref_formatting_stack));
+
+	strbuf_init(&s->output, 0);
+	s->prev = *stack;
+	*stack = s;
+}
+
+static void pop_stack_element(struct ref_formatting_stack **stack)
+{
+	struct ref_formatting_stack *current = *stack;
+	struct ref_formatting_stack *prev = current->prev;
+
+	if (prev)
+		strbuf_addbuf(&prev->output, &current->output);
+	strbuf_release(&current->output);
+	free(current);
+	*stack = prev;
+}
+
+static void end_align_handler(struct ref_formatting_stack *stack)
+{
+	struct align *align = (struct align *)stack->at_end_data;
+	struct strbuf s = STRBUF_INIT;
+
+	strbuf_utf8_align(&s, align->position, align->width, stack->output.buf);
+	strbuf_swap(&stack->output, &s);
+	strbuf_release(&s);
+}
+
+static void align_atom_handler(struct atom_value *atomv, struct ref_formatting_state *state)
+{
+	struct ref_formatting_stack *new;
+
+	push_stack_element(&state->stack);
+	new = state->stack;
+	new->at_end = end_align_handler;
+	new->at_end_data = &atomv->u.align;
+}
+
+static void end_atom_handler(struct atom_value *atomv, struct ref_formatting_state *state)
+{
+	struct ref_formatting_stack *current = state->stack;
+	struct strbuf s = STRBUF_INIT;
+
+	if (!current->at_end)
+		die(_("format: %%(end) atom used without corresponding atom"));
+	current->at_end(current);
+
+	/*
+	 * Perform quote formatting when the stack element is that of
+	 * a supporting atom. If nested then perform quote formatting
+	 * only on the topmost supporting atom.
+	 */
+	if (!state->stack->prev->prev) {
+		quote_formatting(&s, current->output.buf, state->quote_style);
+		strbuf_swap(&current->output, &s);
+	}
+	strbuf_release(&s);
+	pop_stack_element(&state->stack);
+}
+
+static int match_atom_name(const char *name, const char *atom_name, const char **val)
+{
+	const char *body;
+
+	if (!skip_prefix(name, atom_name, &body))
+		return 0; /* doesn't even begin with "atom_name" */
+	if (!body[0]) {
+		*val = NULL; /* %(atom_name) and no customization */
+		return 1;
+	}
+	if (body[0] != ':')
+		return 0; /* "atom_namefoo" is not "atom_name" or "atom_name:..." */
+	*val = body + 1; /* "atom_name:val" */
+	return 1;
+}
+
 /*
  * In a format string, find the next occurrence of %(atom).
  */
@@ -498,6 +648,30 @@ static void find_subpos(const char *buf, unsigned long sz,
 	*nonsiglen = *sig - buf;
 }
 
+/*
+ * If 'lines' is greater than 0, append that many lines from the given
+ * 'buf' of length 'size' to the given strbuf.
+ */
+static void append_lines(struct strbuf *out, const char *buf, unsigned long size, int lines)
+{
+	int i;
+	const char *sp, *eol;
+	size_t len;
+
+	sp = buf;
+
+	for (i = 0; i < lines && sp < buf + size; i++) {
+		if (i)
+			strbuf_addstr(out, "\n    ");
+		eol = memchr(sp, '\n', size - (sp - buf));
+		len = eol ? eol - sp : size - (sp - buf);
+		strbuf_add(out, sp, len);
+		if (!eol)
+			break;
+		sp = eol + 1;
+	}
+}
+
 /* See grab_values */
 static void grab_sub_body_contents(struct atom_value *val, int deref, struct object *obj, void *buf, unsigned long sz)
 {
@@ -508,6 +682,7 @@ static void grab_sub_body_contents(struct atom_value *val, int deref, struct obj
 	for (i = 0; i < used_atom_cnt; i++) {
 		const char *name = used_atom[i];
 		struct atom_value *v = &val[i];
+		const char *valp = NULL;
 		if (!!deref != (*name == '*'))
 			continue;
 		if (deref)
@@ -517,7 +692,8 @@ static void grab_sub_body_contents(struct atom_value *val, int deref, struct obj
 		    strcmp(name, "contents") &&
 		    strcmp(name, "contents:subject") &&
 		    strcmp(name, "contents:body") &&
-		    strcmp(name, "contents:signature"))
+		    strcmp(name, "contents:signature") &&
+		    !starts_with(name, "contents:lines="))
 			continue;
 		if (!subpos)
 			find_subpos(buf, sz,
@@ -537,6 +713,16 @@ static void grab_sub_body_contents(struct atom_value *val, int deref, struct obj
 			v->s = xmemdupz(sigpos, siglen);
 		else if (!strcmp(name, "contents"))
 			v->s = xstrdup(subpos);
+		else if (skip_prefix(name, "contents:lines=", &valp)) {
+			struct strbuf s = STRBUF_INIT;
+			const char *contents_end = bodylen + bodypos - siglen;
+
+			if (strtoul_ui(valp, 10, &v->u.contents.lines))
+				die(_("positive value expected contents:lines=%s"), valp);
+			/*  Size is the length of the message after removing the signature */
+			append_lines(&s, subpos, contents_end - subpos, v->u.contents.lines);
+			v->s = strbuf_detach(&s, NULL);
+		}
 	}
 }
 
@@ -622,8 +808,11 @@ static void populate_value(struct ref_array_item *ref)
 		int deref = 0;
 		const char *refname;
 		const char *formatp;
+		const char *valp;
 		struct branch *branch = NULL;
 
+		v->handler = append_atom;
+
 		if (*name == '*') {
 			deref = 1;
 			name++;
@@ -654,10 +843,12 @@ static void populate_value(struct ref_array_item *ref)
 			refname = branch_get_push(branch, NULL);
 			if (!refname)
 				continue;
-		} else if (starts_with(name, "color:")) {
+		} else if (match_atom_name(name, "color", &valp)) {
 			char color[COLOR_MAXLEN] = "";
 
-			if (color_parse(name + 6, color) < 0)
+			if (!valp)
+				die(_("expected format: %%(color:<color>)"));
+			if (color_parse(valp, color) < 0)
 				die(_("unable to parse format"));
 			v->s = xstrdup(color);
 			continue;
@@ -687,6 +878,48 @@ static void populate_value(struct ref_array_item *ref)
 			else
 				v->s = " ";
 			continue;
+		} else if (match_atom_name(name, "align", &valp)) {
+			struct align *align = &v->u.align;
+			struct strbuf **s, **to_free;
+			int width = -1;
+
+			if (!valp)
+				die(_("expected format: %%(align:<width>,<position>)"));
+
+			/*
+			 * TODO: Implement a function similar to strbuf_split_str()
+			 * which would omit the separator from the end of each value.
+			 */
+			s = to_free = strbuf_split_str(valp, ',', 0);
+
+			align->position = ALIGN_LEFT;
+
+			while (*s) {
+				/*  Strip trailing comma */
+				if (s[1])
+					strbuf_setlen(s[0], s[0]->len - 1);
+				if (!strtoul_ui(s[0]->buf, 10, (unsigned int *)&width))
+					;
+				else if (!strcmp(s[0]->buf, "left"))
+					align->position = ALIGN_LEFT;
+				else if (!strcmp(s[0]->buf, "right"))
+					align->position = ALIGN_RIGHT;
+				else if (!strcmp(s[0]->buf, "middle"))
+					align->position = ALIGN_MIDDLE;
+				else
+					die(_("improper format entered align:%s"), s[0]->buf);
+				s++;
+			}
+
+			if (width < 0)
+				die(_("positive width expected with the %%(align) atom"));
+			align->width = width;
+			strbuf_list_free(to_free);
+			v->handler = align_atom_handler;
+			continue;
+		} else if (!strcmp(name, "end")) {
+			v->handler = end_atom_handler;
+			continue;
 		} else
 			continue;
 
@@ -928,9 +1161,33 @@ static int commit_contains(struct ref_filter *filter, struct commit *commit)
 
 /*
  * Return 1 if the refname matches one of the patterns, otherwise 0.
+ * A pattern can be a literal prefix (e.g. a refname "refs/heads/master"
+ * matches a pattern "refs/heads/mas") or a wildcard (e.g. the same ref
+ * matches "refs/heads/mas*", too).
+ */
+static int match_pattern(const char **patterns, const char *refname)
+{
+	/*
+	 * When no '--format' option is given we need to skip the prefix
+	 * for matching refs of tags and branches.
+	 */
+	(void)(skip_prefix(refname, "refs/tags/", &refname) ||
+	       skip_prefix(refname, "refs/heads/", &refname) ||
+	       skip_prefix(refname, "refs/remotes/", &refname) ||
+	       skip_prefix(refname, "refs/", &refname));
+
+	for (; *patterns; patterns++) {
+		if (!wildmatch(*patterns, refname, 0, NULL))
+			return 1;
+	}
+	return 0;
+}
+
+/*
+ * Return 1 if the refname matches one of the patterns, otherwise 0.
  * A pattern can be path prefix (e.g. a refname "refs/heads/master"
- * matches a pattern "refs/heads/") or a wildcard (e.g. the same ref
- * matches "refs/heads/m*",too).
+ * matches a pattern "refs/heads/" but not "refs/heads/m") or a
+ * wildcard (e.g. the same ref matches "refs/heads/m*", too).
  */
 static int match_name_as_path(const char **pattern, const char *refname)
 {
@@ -951,6 +1208,16 @@ static int match_name_as_path(const char **pattern, const char *refname)
 	return 0;
 }
 
+/* Return 1 if the refname matches one of the patterns, otherwise 0. */
+static int filter_pattern_match(struct ref_filter *filter, const char *refname)
+{
+	if (!*filter->name_patterns)
+		return 1; /* No pattern always matches */
+	if (filter->match_as_path)
+		return match_name_as_path(filter->name_patterns, refname);
+	return match_pattern(filter->name_patterns, refname);
+}
+
 /*
  * Given a ref (sha1, refname), check if the ref belongs to the array
  * of sha1s. If the given ref is a tag, check if the given tag points
@@ -998,6 +1265,34 @@ static struct ref_array_item *new_ref_array_item(const char *refname,
 	return ref;
 }
 
+static int filter_ref_kind(struct ref_filter *filter, const char *refname)
+{
+	unsigned int i;
+
+	static struct {
+		const char *prefix;
+		unsigned int kind;
+	} ref_kind[] = {
+		{ "refs/heads/" , FILTER_REFS_BRANCHES },
+		{ "refs/remotes/" , FILTER_REFS_REMOTES },
+		{ "refs/tags/", FILTER_REFS_TAGS}
+	};
+
+	if (filter->kind == FILTER_REFS_BRANCHES ||
+	    filter->kind == FILTER_REFS_REMOTES ||
+	    filter->kind == FILTER_REFS_TAGS)
+		return filter->kind;
+	else if (!strcmp(refname, "HEAD"))
+		return FILTER_REFS_DETACHED_HEAD;
+
+	for (i = 0; i < ARRAY_SIZE(ref_kind); i++) {
+		if (starts_with(refname, ref_kind[i].prefix))
+			return ref_kind[i].kind;
+	}
+
+	return FILTER_REFS_OTHERS;
+}
+
 /*
  * A call-back given to for_each_ref().  Filter refs and keep them for
  * later object processing.
@@ -1008,6 +1303,7 @@ static int ref_filter_handler(const char *refname, const struct object_id *oid,
 	struct ref_filter *filter = ref_cbdata->filter;
 	struct ref_array_item *ref;
 	struct commit *commit = NULL;
+	unsigned int kind;
 
 	if (flag & REF_BAD_NAME) {
 		warning("ignoring ref with broken name %s", refname);
@@ -1019,7 +1315,12 @@ static int ref_filter_handler(const char *refname, const struct object_id *oid,
 		return 0;
 	}
 
-	if (*filter->name_patterns && !match_name_as_path(filter->name_patterns, refname))
+	/* Obtain the current ref kind from filter_ref_kind() and ignore unwanted refs. */
+	kind = filter_ref_kind(filter, refname);
+	if (!(kind & filter->kind))
+		return 0;
+
+	if (!filter_pattern_match(filter, refname))
 		return 0;
 
 	if (filter->points_at.nr && !match_points_at(&filter->points_at, oid->hash, refname))
@@ -1050,6 +1351,7 @@ static int ref_filter_handler(const char *refname, const struct object_id *oid,
 
 	REALLOC_ARRAY(ref_cbdata->array->items, ref_cbdata->array->nr + 1);
 	ref_cbdata->array->items[ref_cbdata->array->nr++] = ref;
+	ref->kind = kind;
 	return 0;
 }
 
@@ -1126,17 +1428,37 @@ int filter_refs(struct ref_array *array, struct ref_filter *filter, unsigned int
 {
 	struct ref_filter_cbdata ref_cbdata;
 	int ret = 0;
+	unsigned int broken = 0;
 
 	ref_cbdata.array = array;
 	ref_cbdata.filter = filter;
 
+	if (type & FILTER_REFS_INCLUDE_BROKEN)
+		broken = 1;
+	filter->kind = type & FILTER_REFS_KIND_MASK;
+
 	/*  Simple per-ref filtering */
-	if (type & (FILTER_REFS_ALL | FILTER_REFS_INCLUDE_BROKEN))
-		ret = for_each_rawref(ref_filter_handler, &ref_cbdata);
-	else if (type & FILTER_REFS_ALL)
-		ret = for_each_ref(ref_filter_handler, &ref_cbdata);
-	else if (type)
+	if (!filter->kind)
 		die("filter_refs: invalid type");
+	else {
+		/*
+		 * For common cases where we need only branches or remotes or tags,
+		 * we only iterate through those refs. If a mix of refs is needed,
+		 * we iterate over all refs and filter out required refs with the help
+		 * of filter_ref_kind().
+		 */
+		if (filter->kind == FILTER_REFS_BRANCHES)
+			ret = for_each_fullref_in("refs/heads/", ref_filter_handler, &ref_cbdata, broken);
+		else if (filter->kind == FILTER_REFS_REMOTES)
+			ret = for_each_fullref_in("refs/remotes/", ref_filter_handler, &ref_cbdata, broken);
+		else if (filter->kind == FILTER_REFS_TAGS)
+			ret = for_each_fullref_in("refs/tags/", ref_filter_handler, &ref_cbdata, broken);
+		else if (filter->kind & FILTER_REFS_ALL)
+			ret = for_each_fullref_in("", ref_filter_handler, &ref_cbdata, broken);
+		if (!ret && (filter->kind & FILTER_REFS_DETACHED_HEAD))
+			head_ref(ref_filter_handler, &ref_cbdata);
+	}
+
 
 	/*  Filters that need revision walking */
 	if (filter->merge_commit)
@@ -1153,19 +1475,19 @@ static int cmp_ref_sorting(struct ref_sorting *s, struct ref_array_item *a, stru
 
 	get_ref_atom_value(a, s->atom, &va);
 	get_ref_atom_value(b, s->atom, &vb);
-	switch (cmp_type) {
-	case FIELD_STR:
+	if (s->version)
+		cmp = versioncmp(va->s, vb->s);
+	else if (cmp_type == FIELD_STR)
 		cmp = strcmp(va->s, vb->s);
-		break;
-	default:
+	else {
 		if (va->ul < vb->ul)
 			cmp = -1;
 		else if (va->ul == vb->ul)
 			cmp = 0;
 		else
 			cmp = 1;
-		break;
 	}
+
 	return (s->reverse) ? -cmp : cmp;
 }
 
@@ -1190,32 +1512,6 @@ void ref_array_sort(struct ref_sorting *sorting, struct ref_array *array)
 	qsort(array->items, array->nr, sizeof(struct ref_array_item *), compare_refs);
 }
 
-static void print_value(struct atom_value *v, int quote_style)
-{
-	struct strbuf sb = STRBUF_INIT;
-	switch (quote_style) {
-	case QUOTE_NONE:
-		fputs(v->s, stdout);
-		break;
-	case QUOTE_SHELL:
-		sq_quote_buf(&sb, v->s);
-		break;
-	case QUOTE_PERL:
-		perl_quote_buf(&sb, v->s);
-		break;
-	case QUOTE_PYTHON:
-		python_quote_buf(&sb, v->s);
-		break;
-	case QUOTE_TCL:
-		tcl_quote_buf(&sb, v->s);
-		break;
-	}
-	if (quote_style != QUOTE_NONE) {
-		fputs(sb.buf, stdout);
-		strbuf_release(&sb);
-	}
-}
-
 static int hex1(char ch)
 {
 	if ('0' <= ch && ch <= '9')
@@ -1234,8 +1530,10 @@ static int hex2(const char *cp)
 		return -1;
 }
 
-static void emit(const char *cp, const char *ep)
+static void append_literal(const char *cp, const char *ep, struct ref_formatting_state *state)
 {
+	struct strbuf *s = &state->stack->output;
+
 	while (*cp && (!ep || cp < ep)) {
 		if (*cp == '%') {
 			if (cp[1] == '%')
@@ -1243,13 +1541,13 @@ static void emit(const char *cp, const char *ep)
 			else {
 				int ch = hex2(cp + 1);
 				if (0 <= ch) {
-					putchar(ch);
+					strbuf_addch(s, ch);
 					cp += 3;
 					continue;
 				}
 			}
 		}
-		putchar(*cp);
+		strbuf_addch(s, *cp);
 		cp++;
 	}
 }
@@ -1257,19 +1555,24 @@ static void emit(const char *cp, const char *ep)
 void show_ref_array_item(struct ref_array_item *info, const char *format, int quote_style)
 {
 	const char *cp, *sp, *ep;
+	struct strbuf *final_buf;
+	struct ref_formatting_state state = REF_FORMATTING_STATE_INIT;
+
+	state.quote_style = quote_style;
+	push_stack_element(&state.stack);
 
 	for (cp = format; *cp && (sp = find_next(cp)); cp = ep + 1) {
 		struct atom_value *atomv;
 
 		ep = strchr(sp, ')');
 		if (cp < sp)
-			emit(cp, sp);
+			append_literal(cp, sp, &state);
 		get_ref_atom_value(info, parse_ref_filter_atom(sp + 2, ep), &atomv);
-		print_value(atomv, quote_style);
+		atomv->handler(atomv, &state);
 	}
 	if (*cp) {
 		sp = cp + strlen(cp);
-		emit(cp, sp);
+		append_literal(cp, sp, &state);
 	}
 	if (need_color_reset_at_eol) {
 		struct atom_value resetv;
@@ -1278,8 +1581,13 @@ void show_ref_array_item(struct ref_array_item *info, const char *format, int qu
 		if (color_parse("reset", color) < 0)
 			die("BUG: couldn't parse 'reset' as a color");
 		resetv.s = color;
-		print_value(&resetv, quote_style);
+		append_atom(&resetv, &state);
 	}
+	if (state.stack->prev)
+		die(_("format: %%(end) atom missing"));
+	final_buf = &state.stack->output;
+	fwrite(final_buf->buf, 1, final_buf->len, stdout);
+	pop_stack_element(&state.stack);
 	putchar('\n');
 }
 
@@ -1312,6 +1620,9 @@ int parse_opt_ref_sorting(const struct option *opt, const char *arg, int unset)
 		s->reverse = 1;
 		arg++;
 	}
+	if (skip_prefix(arg, "version:", &arg) ||
+	    skip_prefix(arg, "v:", &arg))
+		s->version = 1;
 	len = strlen(arg);
 	s->atom = parse_ref_filter_atom(arg, arg+len);
 	return 0;
diff --git a/ref-filter.h b/ref-filter.h
index 6bf27d8bc4..a5cfa5e677 100644
--- a/ref-filter.h
+++ b/ref-filter.h
@@ -13,23 +13,29 @@
 #define QUOTE_PYTHON 4
 #define QUOTE_TCL 8
 
-#define FILTER_REFS_INCLUDE_BROKEN 0x1
-#define FILTER_REFS_ALL 0x2
+#define FILTER_REFS_INCLUDE_BROKEN 0x0001
+#define FILTER_REFS_TAGS           0x0002
+#define FILTER_REFS_BRANCHES       0x0004
+#define FILTER_REFS_REMOTES        0x0008
+#define FILTER_REFS_OTHERS         0x0010
+#define FILTER_REFS_ALL            (FILTER_REFS_TAGS | FILTER_REFS_BRANCHES | \
+				    FILTER_REFS_REMOTES | FILTER_REFS_OTHERS)
+#define FILTER_REFS_DETACHED_HEAD  0x0020
+#define FILTER_REFS_KIND_MASK      (FILTER_REFS_ALL | FILTER_REFS_DETACHED_HEAD)
 
-struct atom_value {
-	const char *s;
-	unsigned long ul; /* used for sorting when not FIELD_STR */
-};
+struct atom_value;
 
 struct ref_sorting {
 	struct ref_sorting *next;
 	int atom; /* index into used_atom array (internal) */
-	unsigned reverse : 1;
+	unsigned reverse : 1,
+		version : 1;
 };
 
 struct ref_array_item {
 	unsigned char objectname[20];
 	int flag;
+	unsigned int kind;
 	const char *symref;
 	struct commit *commit;
 	struct atom_value *value;
@@ -53,7 +59,10 @@ struct ref_filter {
 	} merge;
 	struct commit *merge_commit;
 
-	unsigned int with_commit_tag_algo : 1;
+	unsigned int with_commit_tag_algo : 1,
+		match_as_path : 1;
+	unsigned int kind,
+		lines;
 };
 
 struct ref_filter_cbdata {
diff --git a/refs.c b/refs.c
index 24401f71f8..91c88bad4a 100644
--- a/refs.c
+++ b/refs.c
@@ -2131,6 +2131,15 @@ int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data)
 	return do_for_each_ref(&ref_cache, prefix, fn, strlen(prefix), 0, cb_data);
 }
 
+int for_each_fullref_in(const char *prefix, each_ref_fn fn, void *cb_data, unsigned int broken)
+{
+	unsigned int flag = 0;
+
+	if (broken)
+		flag = DO_FOR_EACH_INCLUDE_BROKEN;
+	return do_for_each_ref(&ref_cache, prefix, fn, 0, flag, cb_data);
+}
+
 int for_each_ref_in_submodule(const char *submodule, const char *prefix,
 		each_ref_fn fn, void *cb_data)
 {
diff --git a/refs.h b/refs.h
index e9a5f3230a..6d30c980d1 100644
--- a/refs.h
+++ b/refs.h
@@ -173,6 +173,7 @@ typedef int each_ref_fn(const char *refname,
 extern int head_ref(each_ref_fn fn, void *cb_data);
 extern int for_each_ref(each_ref_fn fn, void *cb_data);
 extern int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data);
+extern int for_each_fullref_in(const char *prefix, each_ref_fn fn, void *cb_data, unsigned int broken);
 extern int for_each_tag_ref(each_ref_fn fn, void *cb_data);
 extern int for_each_branch_ref(each_ref_fn fn, void *cb_data);
 extern int for_each_remote_ref(each_ref_fn fn, void *cb_data);
diff --git a/t/t6302-for-each-ref-filter.sh b/t/t6302-for-each-ref-filter.sh
index 505a360161..fe4796cc9c 100755
--- a/t/t6302-for-each-ref-filter.sh
+++ b/t/t6302-for-each-ref-filter.sh
@@ -81,4 +81,178 @@ test_expect_success 'filtering with --contains' '
 	test_cmp expect actual
 '
 
+test_expect_success '%(color) must fail' '
+	test_must_fail git for-each-ref --format="%(color)%(refname)"
+'
+
+test_expect_success 'left alignment is default' '
+	cat >expect <<-\EOF &&
+	refname is refs/heads/master  |refs/heads/master
+	refname is refs/heads/side    |refs/heads/side
+	refname is refs/odd/spot      |refs/odd/spot
+	refname is refs/tags/double-tag|refs/tags/double-tag
+	refname is refs/tags/four     |refs/tags/four
+	refname is refs/tags/one      |refs/tags/one
+	refname is refs/tags/signed-tag|refs/tags/signed-tag
+	refname is refs/tags/three    |refs/tags/three
+	refname is refs/tags/two      |refs/tags/two
+	EOF
+	git for-each-ref --format="%(align:30)refname is %(refname)%(end)|%(refname)" >actual &&
+	test_cmp expect actual
+'
+
+test_expect_success 'middle alignment' '
+	cat >expect <<-\EOF &&
+	| refname is refs/heads/master |refs/heads/master
+	|  refname is refs/heads/side  |refs/heads/side
+	|   refname is refs/odd/spot   |refs/odd/spot
+	|refname is refs/tags/double-tag|refs/tags/double-tag
+	|  refname is refs/tags/four   |refs/tags/four
+	|   refname is refs/tags/one   |refs/tags/one
+	|refname is refs/tags/signed-tag|refs/tags/signed-tag
+	|  refname is refs/tags/three  |refs/tags/three
+	|   refname is refs/tags/two   |refs/tags/two
+	EOF
+	git for-each-ref --format="|%(align:middle,30)refname is %(refname)%(end)|%(refname)" >actual &&
+	test_cmp expect actual
+'
+
+test_expect_success 'right alignment' '
+	cat >expect <<-\EOF &&
+	|  refname is refs/heads/master|refs/heads/master
+	|    refname is refs/heads/side|refs/heads/side
+	|      refname is refs/odd/spot|refs/odd/spot
+	|refname is refs/tags/double-tag|refs/tags/double-tag
+	|     refname is refs/tags/four|refs/tags/four
+	|      refname is refs/tags/one|refs/tags/one
+	|refname is refs/tags/signed-tag|refs/tags/signed-tag
+	|    refname is refs/tags/three|refs/tags/three
+	|      refname is refs/tags/two|refs/tags/two
+	EOF
+	git for-each-ref --format="|%(align:30,right)refname is %(refname)%(end)|%(refname)" >actual &&
+	test_cmp expect actual
+'
+
+# Individual atoms inside %(align:...) and %(end) must not be quoted.
+
+test_expect_success 'alignment with format quote' "
+	cat >expect <<-\EOF &&
+	|'      '\''master| A U Thor'\''      '|
+	|'       '\''side| A U Thor'\''       '|
+	|'     '\''odd/spot| A U Thor'\''     '|
+	|'        '\''double-tag| '\''        '|
+	|'       '\''four| A U Thor'\''       '|
+	|'       '\''one| A U Thor'\''        '|
+	|'        '\''signed-tag| '\''        '|
+	|'      '\''three| A U Thor'\''       '|
+	|'       '\''two| A U Thor'\''        '|
+	EOF
+	git for-each-ref --shell --format=\"|%(align:30,middle)'%(refname:short)| %(authorname)'%(end)|\" >actual &&
+	test_cmp expect actual
+"
+
+test_expect_success 'nested alignment with quote formatting' "
+	cat >expect <<-\EOF &&
+	|'         master               '|
+	|'           side               '|
+	|'       odd/spot               '|
+	|'     double-tag               '|
+	|'           four               '|
+	|'            one               '|
+	|'     signed-tag               '|
+	|'          three               '|
+	|'            two               '|
+	EOF
+	git for-each-ref --shell --format='|%(align:30,left)%(align:15,right)%(refname:short)%(end)%(end)|' >actual &&
+	test_cmp expect actual
+"
+
+test_expect_success 'check `%(contents:lines=1)`' '
+	cat >expect <<-\EOF &&
+	master |three
+	side |four
+	odd/spot |three
+	double-tag |Annonated doubly
+	four |four
+	one |one
+	signed-tag |A signed tag message
+	three |three
+	two |two
+	EOF
+	git for-each-ref --format="%(refname:short) |%(contents:lines=1)" >actual &&
+	test_cmp expect actual
+'
+
+test_expect_success 'check `%(contents:lines=0)`' '
+	cat >expect <<-\EOF &&
+	master |
+	side |
+	odd/spot |
+	double-tag |
+	four |
+	one |
+	signed-tag |
+	three |
+	two |
+	EOF
+	git for-each-ref --format="%(refname:short) |%(contents:lines=0)" >actual &&
+	test_cmp expect actual
+'
+
+test_expect_success 'check `%(contents:lines=99999)`' '
+	cat >expect <<-\EOF &&
+	master |three
+	side |four
+	odd/spot |three
+	double-tag |Annonated doubly
+	four |four
+	one |one
+	signed-tag |A signed tag message
+	three |three
+	two |two
+	EOF
+	git for-each-ref --format="%(refname:short) |%(contents:lines=99999)" >actual &&
+	test_cmp expect actual
+'
+
+test_expect_success '`%(contents:lines=-1)` should fail' '
+	test_must_fail git for-each-ref --format="%(refname:short) |%(contents:lines=-1)"
+'
+
+test_expect_success 'setup for version sort' '
+	test_commit foo1.3 &&
+	test_commit foo1.6 &&
+	test_commit foo1.10
+'
+
+test_expect_success 'version sort' '
+	git for-each-ref --sort=version:refname --format="%(refname:short)" refs/tags/ | grep "foo" >actual &&
+	cat >expect <<-\EOF &&
+	foo1.3
+	foo1.6
+	foo1.10
+	EOF
+	test_cmp expect actual
+'
+
+test_expect_success 'version sort (shortened)' '
+	git for-each-ref --sort=v:refname --format="%(refname:short)" refs/tags/ | grep "foo" >actual &&
+	cat >expect <<-\EOF &&
+	foo1.3
+	foo1.6
+	foo1.10
+	EOF
+	test_cmp expect actual
+'
+
+test_expect_success 'reverse version sort' '
+	git for-each-ref --sort=-version:refname --format="%(refname:short)" refs/tags/ | grep "foo" >actual &&
+	cat >expect <<-\EOF &&
+	foo1.10
+	foo1.6
+	foo1.3
+	EOF
+	test_cmp expect actual
+'
+
 test_done
diff --git a/t/t7004-tag.sh b/t/t7004-tag.sh
index d31788cc6c..3dd2f51e49 100755
--- a/t/t7004-tag.sh
+++ b/t/t7004-tag.sh
@@ -1462,13 +1462,7 @@ test_expect_success 'invalid sort parameter on command line' '
 
 test_expect_success 'invalid sort parameter in configuratoin' '
 	git config tag.sort "v:notvalid" &&
-	git tag -l "foo*" >actual &&
-	cat >expect <<-\EOF &&
-	foo1.10
-	foo1.3
-	foo1.6
-	EOF
-	test_cmp expect actual
+	test_must_fail git tag -l "foo*"
 '
 
 test_expect_success 'version sort with prerelease reordering' '
@@ -1525,4 +1519,43 @@ EOF"
 	test_cmp expect actual
 '
 
+test_expect_success '--format should list tags as per format given' '
+	cat >expect <<-\EOF &&
+	refname : refs/tags/foo1.10
+	refname : refs/tags/foo1.3
+	refname : refs/tags/foo1.6
+	refname : refs/tags/foo1.6-rc1
+	refname : refs/tags/foo1.6-rc2
+	EOF
+	git tag -l --format="refname : %(refname)" "foo*" >actual &&
+	test_cmp expect actual
+'
+
+test_expect_success 'setup --merged test tags' '
+	git tag mergetest-1 HEAD~2 &&
+	git tag mergetest-2 HEAD~1 &&
+	git tag mergetest-3 HEAD
+'
+
+test_expect_success '--merged cannot be used in non-list mode' '
+	test_must_fail git tag --merged=mergetest-2 foo
+'
+
+test_expect_success '--merged shows merged tags' '
+	cat >expect <<-\EOF &&
+	mergetest-1
+	mergetest-2
+	EOF
+	git tag -l --merged=mergetest-2 mergetest-* >actual &&
+	test_cmp expect actual
+'
+
+test_expect_success '--no-merged show unmerged tags' '
+	cat >expect <<-\EOF &&
+	mergetest-3
+	EOF
+	git tag -l --no-merged=mergetest-2 mergetest-* >actual &&
+	test_cmp expect actual
+'
+
 test_done
diff --git a/utf8.c b/utf8.c
index 28e6d76a42..00e10c86ad 100644
--- a/utf8.c
+++ b/utf8.c
@@ -644,3 +644,24 @@ int skip_utf8_bom(char **text, size_t len)
 	*text += strlen(utf8_bom);
 	return 1;
 }
+
+void strbuf_utf8_align(struct strbuf *buf, align_type position, unsigned int width,
+		       const char *s)
+{
+	int slen = strlen(s);
+	int display_len = utf8_strnwidth(s, slen, 0);
+	int utf8_compensation = slen - display_len;
+
+	if (display_len >= width) {
+		strbuf_addstr(buf, s);
+		return;
+	}
+
+	if (position == ALIGN_LEFT)
+		strbuf_addf(buf, "%-*s", width + utf8_compensation, s);
+	else if (position == ALIGN_MIDDLE) {
+		int left = (width - display_len) / 2;
+		strbuf_addf(buf, "%*s%-*s", left, "", width - left + utf8_compensation, s);
+	} else if (position == ALIGN_RIGHT)
+		strbuf_addf(buf, "%*s", width + utf8_compensation, s);
+}
diff --git a/utf8.h b/utf8.h
index 5a9e94bee6..7930b44f19 100644
--- a/utf8.h
+++ b/utf8.h
@@ -55,4 +55,19 @@ int mbs_chrlen(const char **text, size_t *remainder_p, const char *encoding);
  */
 int is_hfs_dotgit(const char *path);
 
+typedef enum {
+	ALIGN_LEFT,
+	ALIGN_MIDDLE,
+	ALIGN_RIGHT
+} align_type;
+
+/*
+ * Align the string given and store it into a strbuf as per the
+ * 'position' and 'width'. If the given string length is larger than
+ * 'width' than then the input string is not truncated and no
+ * alignment is done.
+ */
+void strbuf_utf8_align(struct strbuf *buf, align_type position, unsigned int width,
+		       const char *s);
+
 #endif