Merge branch 'np/maint-1.6.3-deepen'

* np/maint-1.6.3-deepen:
  fix simple deepening of a repo

Conflicts:
	t/t5500-fetch-pack.sh

t/t5500-fetch-pack.sh

@@ -139,6 +139,36 @@ test_expect_success 'fsck in shallow repo' '
 	)
 '
 
+test_expect_success 'simple fetch in shallow repo' '
+	(
+		cd shallow &&
+		git fetch
+	)
+'
+
+test_expect_success 'no changes expected' '
+	(
+		cd shallow &&
+		git count-objects -v
+	) > count.shallow.2 &&
+	cmp count.shallow count.shallow.2
+'
+
+test_expect_success 'fetch same depth in shallow repo' '
+	(
+		cd shallow &&
+		git fetch --depth=2
+	)
+'
+
+test_expect_success 'no changes expected' '
+	(
+		cd shallow &&
+		git count-objects -v
+	) > count.shallow.3 &&
+	cmp count.shallow count.shallow.3
+'
+
 test_expect_success 'add two more' '
 	add B66 $B65 &&
 	add B67 $B66
@@ -201,4 +231,21 @@ test_expect_success 'pull in shallow repo with missing merge base' '
 	)
 '
 
+test_expect_success 'additional simple shallow deepenings' '
+	(
+		cd shallow &&
+		git fetch --depth=8 &&
+		git fetch --depth=10 &&
+		git fetch --depth=11
+	)
+'
+
+test_expect_success 'clone shallow object count' '
+	(
+		cd shallow &&
+		git count-objects -v
+	) > count.shallow &&
+	grep "^count: 52" count.shallow
+'
+
 test_done

transport.c

@@ -1059,18 +1059,32 @@ const struct ref *transport_get_remote_refs(struct transport *transport)
 int transport_fetch_refs(struct transport *transport, const struct ref *refs)
 {
 	int rc;
-	int nr_heads = 0, nr_alloc = 0;
+	int nr_heads = 0, nr_alloc = 0, nr_refs = 0;
 	const struct ref **heads = NULL;
 	const struct ref *rm;
 
 	for (rm = refs; rm; rm = rm->next) {
+		nr_refs++;
 		if (rm->peer_ref &&
 		    !hashcmp(rm->peer_ref->old_sha1, rm->old_sha1))
 			continue;
 		ALLOC_GROW(heads, nr_heads + 1, nr_alloc);
 		heads[nr_heads++] = rm;
 	}
 
+	if (!nr_heads) {
+		/*
+		 * When deepening of a shallow repository is requested,
+		 * then local and remote refs are likely to still be equal.
+		 * Just feed them all to the fetch method in that case.
+		 * This condition shouldn't be met in a non-deepening fetch
+		 * (see builtin-fetch.c:quickfetch()).
+		 */
+		heads = xmalloc(nr_refs * sizeof(*heads));
+		for (rm = refs; rm; rm = rm->next)
+			heads[nr_heads++] = rm;
+	}
+
 	rc = transport->fetch(transport, nr_heads, heads);
 	free(heads);
 	return rc;