[PATCH] ref-filter: sort numerically when ":size" is used

[Kousik Sanagavarapu <five231003@gmail.com>]

Atoms like "raw" and "contents" have a ":size" option which can be used
to know the size of the data. Since these atoms have the cmp_type
FIELD_STR, they are sorted alphabetically from 'a' to 'z' and '0' to
'9'. Meaning, even when the ":size" option is used and what we
ultimatlely have is numbers, we still sort alphabetically.

For example, consider the the following case in a repo

refname			contents:size		raw:size
=======			=============		========
refs/heads/branch1	1130			1210
refs/heads/master	300			410
refs/tags/v1.0		140			260

Sorting with "--format="%(refname) %(contents:size) --sort=contents:size"
would give

refs/heads/branch1 1130
refs/tags/v1.0.0 140
refs/heads/master 300

which is an alphabetic sort, while what one might really expect is

refs/tags/v1.0.0 140
refs/heads/master 300
refs/heads/branch1 1130

which is a numeric sort (that is, a "$ sort -n file" as opposed to a
"$ sort file", where "file" contains only the "contents:size" or
"raw:size" info, each of which is on a newline).

Same is the case with "--sort=raw:size".

So, sort numerically whenever the sort is done with "contents:size" or
"raw:size" and do it the normal alphabetic way when "contents" or "raw"
are used with some other option (they are FIELD_STR anyways).

Signed-off-by: Kousik Sanagavarapu <five231003@gmail.com>
---
 ref-filter.c            | 20 +++++++++++++++-----
 t/t6300-for-each-ref.sh | 15 +++++++++++++--
 2 files changed, 28 insertions(+), 7 deletions(-)

diff --git a/ref-filter.c b/ref-filter.c
index 1bfaf20fbf..5d7bea5f23 100644
--- a/ref-filter.c
+++ b/ref-filter.c
@@ -932,7 +932,13 @@ struct atom_value {
 	ssize_t s_size;
 	int (*handler)(struct atom_value *atomv, struct ref_formatting_state *state,
 		       struct strbuf *err);
-	uintmax_t value; /* used for sorting when not FIELD_STR */
+
+	/*
+	 * Used for sorting when not FIELD_STR or when FIELD_STR but the
+	 * sort should be numeric and not alphabetic.
+	 */
+	uintmax_t value;
+
 	struct used_atom *atom;
 };
 
@@ -1857,7 +1863,8 @@ static void grab_sub_body_contents(struct atom_value *val, int deref, struct exp
 				v->s = xmemdupz(buf, buf_size);
 				v->s_size = buf_size;
 			} else if (atom->u.raw_data.option == RAW_LENGTH) {
-				v->s = xstrfmt("%"PRIuMAX, (uintmax_t)buf_size);
+				v->value = (uintmax_t)buf_size;
+				v->s = xstrfmt("%"PRIuMAX, v->value);
 			}
 			continue;
 		}
@@ -1883,8 +1890,10 @@ static void grab_sub_body_contents(struct atom_value *val, int deref, struct exp
 			v->s = strbuf_detach(&sb, NULL);
 		} else if (atom->u.contents.option == C_BODY_DEP)
 			v->s = xmemdupz(bodypos, bodylen);
-		else if (atom->u.contents.option == C_LENGTH)
-			v->s = xstrfmt("%"PRIuMAX, (uintmax_t)strlen(subpos));
+		else if (atom->u.contents.option == C_LENGTH) {
+			v->value = (uintmax_t)strlen(subpos);
+			v->s = xstrfmt("%"PRIuMAX, v->value);
+		}
 		else if (atom->u.contents.option == C_BODY)
 			v->s = xmemdupz(bodypos, nonsiglen);
 		else if (atom->u.contents.option == C_SIG)
@@ -2265,6 +2274,7 @@ static int populate_value(struct ref_array_item *ref, struct strbuf *err)
 
 		v->s_size = ATOM_SIZE_UNSPECIFIED;
 		v->handler = append_atom;
+		v->value = 0;
 		v->atom = atom;
 
 		if (*name == '*') {
@@ -2986,7 +2996,7 @@ static int cmp_ref_sorting(struct ref_sorting *s, struct ref_array_item *a, stru
 		cmp_detached_head = 1;
 	} else if (s->sort_flags & REF_SORTING_VERSION) {
 		cmp = versioncmp(va->s, vb->s);
-	} else if (cmp_type == FIELD_STR) {
+	} else if (cmp_type == FIELD_STR && !va->value && !vb->value) {
 		if (va->s_size < 0 && vb->s_size < 0) {
 			int (*cmp_fn)(const char *, const char *);
 			cmp_fn = s->sort_flags & REF_SORTING_ICASE
diff --git a/t/t6300-for-each-ref.sh b/t/t6300-for-each-ref.sh
index aa3c7c03c4..7b943fd34c 100755
--- a/t/t6300-for-each-ref.sh
+++ b/t/t6300-for-each-ref.sh
@@ -1017,16 +1017,16 @@ test_expect_success 'Verify sorts with raw' '
 test_expect_success 'Verify sorts with raw:size' '
 	cat >expected <<-EOF &&
 	refs/myblobs/blob8
-	refs/myblobs/first
 	refs/myblobs/blob7
-	refs/heads/main
 	refs/myblobs/blob4
 	refs/myblobs/blob1
 	refs/myblobs/blob2
 	refs/myblobs/blob3
 	refs/myblobs/blob5
 	refs/myblobs/blob6
+	refs/myblobs/first
 	refs/mytrees/first
+	refs/heads/main
 	EOF
 	git for-each-ref --format="%(refname)" --sort=raw:size \
 		refs/heads/main refs/myblobs/ refs/mytrees/first >actual &&
@@ -1138,6 +1138,17 @@ test_expect_success 'for-each-ref --format compare with cat-file --batch' '
 	test_cmp expected actual
 '
 
+test_expect_success 'verify sorts with contents:size' '
+	cat >expect <<-\EOF &&
+	refs/heads/main
+	refs/heads/newtag
+	refs/heads/ambiguous
+	EOF
+	git for-each-ref --format="%(refname)" \
+		--sort=contents:size refs/heads/ >actual &&
+	test_cmp expect actual
+'
+
 test_expect_success 'set up multiple-sort tags' '
 	for when in 100000 200000
 	do
-- 
2.42.0.51.g5dc72c0fbc.dirty