ref-filter: align: introduce long-form syntax

Introduce optional prefixes "width=" and "position=" for the align atom
so that the atom can be used as "%(align:width=<width>,position=<position>)".

Add Documentation and tests for the same.

Helped-by: Eric Sunshine <sunshine@sunshineco.com>
Signed-off-by: Karthik Nayak <Karthik.188@gmail.com>
Reviewed-by: Eric Sunshine <sunshine@sunshineco.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Documentation/git-for-each-ref.txt

@@ -133,14 +133,18 @@ color::
 
 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.
+	%(align:...) and %(end). The "align:" is followed by
+	`width=<width>` and `position=<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. For brevity, the
+	"width=" and/or "position=" prefixes may be omitted, and bare
+	<width> and <position> used instead.  For instance,
+	`%(align:<width>,<position>)`. 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

ref-filter.c

@@ -78,7 +78,15 @@ static void align_atom_parser(struct used_atom *atom, const char *arg)
 		const char *s = params.items[i].string;
 		int position;
 
-		if (!strtoul_ui(s, 10, &width))
+		if (skip_prefix(s, "position=", &s)) {
+			position = parse_align_position(s);
+			if (position < 0)
+				die(_("unrecognized position:%s"), s);
+			align->position = position;
+		} else if (skip_prefix(s, "width=", &s)) {
+			if (strtoul_ui(s, 10, &width))
+				die(_("unrecognized width:%s"), s);
+		} else if (!strtoul_ui(s, 10, &width))
 			;
 		else if ((position = parse_align_position(s)) >= 0)
 			align->position = position;

t/t6302-for-each-ref-filter.sh

@@ -133,6 +133,48 @@ test_expect_success 'right alignment' '
 	test_cmp expect actual
 '
 
+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
+
+test_align_permutations() {
+	while read -r option
+	do
+		test_expect_success "align:$option" '
+			git for-each-ref --format="|%(align:$option)refname is %(refname)%(end)|%(refname)" >actual &&
+			test_cmp expect actual
+		'
+	done
+}
+
+test_align_permutations <<-\EOF
+	middle,42
+	42,middle
+	position=middle,42
+	42,position=middle
+	middle,width=42
+	width=42,middle
+	position=middle,width=42
+	width=42,position=middle
+EOF
+
+# Last one wins (silently) when multiple arguments of the same type are given
+
+test_align_permutations <<-\EOF
+	32,width=42,middle
+	width=30,42,middle
+	width=42,position=right,middle
+	42,right,position=middle
+EOF
+
 # Individual atoms inside %(align:...) and %(end) must not be quoted.
 
 test_expect_success 'alignment with format quote' "