commit a2109c70b8c1180b4a6b9400e503e37ff4abdda8
from: Oliver Lowe <o@olowe.co>
date: Sat May  3 03:22:56 2025 UTC

m3u8: test more bad resolutions

We don't necessarily need to make it easier to specify Variant test cases,
we can pick the already easy-to-test bits of Variant to make better.

References: https://github.com/untangledco/streaming/issues/34

commit - 18185121cc63011d9f097754c13cdc4cc11fd72b
commit + a2109c70b8c1180b4a6b9400e503e37ff4abdda8
blob - 20dcbafb6a363bd6b7450c989e8750e388189460
blob + 0117911d561fd529fde1dada7019c2b885925615
--- m3u8/parse.go
+++ m3u8/parse.go
@@ -134,9 +134,6 @@ func parseVariant(items chan item) (*Variant, error) {
 				v.Codecs = strings.Split(strings.Trim(it.val, `"`), ",")
 			case "RESOLUTION":
 				it = <-items
-				if it.typ != itemString {
-					return nil, fmt.Errorf("parse resolution attribute: unexpected %s", it)
-				}
 				res, err := parseResolution(it.val)
 				if err != nil {
 					return nil, fmt.Errorf("parse resolution: %w", err)
@@ -179,7 +176,7 @@ func parseVariant(items chan item) (*Variant, error) {
 			case "CLOSED-CAPTIONS":
 				it = <-items
 				if it.typ != itemString {
-					return nil, fmt.Errorf("parse closed-captions: unexpcted %s", it)
+					return nil, fmt.Errorf("parse closed-captions: unexpected %s", it)
 				}
 				v.ClosedCaptions = strings.Trim(it.val, `"`)
 			default:
@@ -192,7 +189,6 @@ func parseVariant(items chan item) (*Variant, error) {
 			return &v, nil
 		}
 	}
-	fmt.Println(v)
 	return &v, nil
 }
 
@@ -209,6 +205,9 @@ func parseResolution(s string) (res [2]int, err error)
 	if err != nil {
 		return res, fmt.Errorf("vertical pixels: %v", err)
 	}
+	if res[0] < 0 || res[1] < 0 {
+		return res, fmt.Errorf("negative dimensions")
+	}
 	return res, nil
 }
 
blob - 8614b5d3dff6b87a4b67ccf09b7e89a9543f3348
blob + 96e924816a03c74379ff972dad1afc1f44551989
--- m3u8/parse_test.go
+++ m3u8/parse_test.go
@@ -150,3 +150,24 @@ func TestParseSequence(t *testing.T) {
 		t.Errorf("want %d, got %d", 91240, plist.Sequence)
 	}
 }
+
+func TestResolution(t *testing.T) {
+	var tests = []struct {
+		name string
+		s    string
+	}{
+		{"double x", "1280xx720"},
+		{"missing x", "1280720"},
+		{"missing height", "1280x"},
+		{"negative", "-1x-1"},
+		{"decimal", "10.69x20"},
+	}
+
+	for _, tt := range tests {
+		_, err := parseResolution(tt.s)
+		if err == nil {
+			t.Errorf("parse resolution %q (%s): no error", tt.s, tt.name)
+			continue
+		}
+	}
+}