maintner/maintnerd/maintapi/version: allow .0 suffixes

Happily, the return values for 1.21 and 1.21.0 are the same, so I see no
reason to worry about further impact. Just need to disable the
now-unnecessary validation.

For golang/go#57631

Change-Id: Ice467f993c1e5d304bd5b24fbc21bf4fa66fb4a4
Reviewed-on: https://go-review.googlesource.com/c/build/+/479556
Reviewed-by: Carlos Amedee <[email protected]>
Reviewed-by: Dmitri Shuralyov <[email protected]>
Run-TryBot: Heschi Kreinick <[email protected]>
TryBot-Result: Gopher Robot <[email protected]>
Reviewed-by: Dmitri Shuralyov <[email protected]>
Auto-Submit: Heschi Kreinick <[email protected]>

Author: heschi

maintner/maintnerd/maintapi/version/version.go

@@ -25,11 +25,6 @@ func ParseTag(tagName string) (major, minor, patch int, ok bool) {
 	if !strings.HasPrefix(tagName, prefix) {
 		return 0, 0, 0, false
 	}
-	if strings.HasSuffix(tagName, ".0") {
-		// Trailing zero version components must be omitted in Go tags,
-		// so reject if we see one.
-		return 0, 0, 0, false
-	}
 	v := strings.SplitN(tagName[len(prefix):], ".", 4)
 	if len(v) > 3 {
 		return 0, 0, 0, false

maintner/maintnerd/maintapi/version/version_test.go

@@ -18,6 +18,7 @@ func TestParseTag(t *testing.T) {
 	}{
 		{"go1", 1, 0, 0, true},
 		{"go1.2", 1, 2, 0, true},
+		{"go1.2.0", 1, 2, 0, true},
 		{"go1.2.3", 1, 2, 3, true},
 		{"go23.45.67", 23, 45, 67, true},
 		{"not-go", 0, 0, 0, false},
@@ -38,9 +39,6 @@ func TestParseTag(t *testing.T) {
 		{"go01", 0, 0, 0, false},
 		{"go001", 0, 0, 0, false},
 		{"go1000", 0, 0, 0, false},
-		{"go1.0", 0, 0, 0, false},
-		{"go1.0.0", 0, 0, 0, false},
-		{"go1.2.0", 0, 0, 0, false},
 		{"go00", 0, 0, 0, false},
 		{"go00.2", 0, 0, 0, false},
 		{"go00.2.3", 0, 0, 0, false},