--no-video flag

cmd/mxl-pattern/main_test.go

@@ -95,6 +95,69 @@ func TestValidateAudioArgsSkipsDisabledAudio(t *testing.T) {
 	}
 }
 
+func TestValidateVideoArgsSkipsDisabledVideo(t *testing.T) {
+	args := appArgs{
+		noVideo:    true,
+		pattern:    "not-a-pattern",
+		videoWidth: 1,
+		videoFPS:   "unsupported",
+		videoUUID:  "not-a-uuid",
+	}
+
+	if err := validateVideoArgs(&args); err != nil {
+		t.Fatalf("validateVideoArgs: %v", err)
+	}
+	if args.videoUUID != "not-a-uuid" {
+		t.Fatalf("video UUID changed while video is disabled: %q", args.videoUUID)
+	}
+}
+
+func TestValidateMediaSelection(t *testing.T) {
+	tests := []struct {
+		name       string
+		args       appArgs
+		wantErrSub string
+	}{
+		{
+			name:       "no video with video definition",
+			args:       appArgs{noVideo: true, videoFlowDefFile: "video.json", audioChannels: 2},
+			wantErrSub: "cannot be used with --video",
+		},
+		{
+			name:       "no flows",
+			args:       appArgs{noVideo: true},
+			wantErrSub: "requires audio enabled",
+		},
+		{
+			name: "generated audio only",
+			args: appArgs{noVideo: true, audioChannels: 2},
+		},
+		{
+			name: "external audio only",
+			args: appArgs{noVideo: true, audioFlowDefFile: "audio.json"},
+		},
+		{
+			name: "video enabled by default",
+			args: appArgs{},
+		},
+	}
+
+	for _, tc := range tests {
+		t.Run(tc.name, func(t *testing.T) {
+			err := validateMediaSelection(tc.args)
+			if tc.wantErrSub == "" {
+				if err != nil {
+					t.Fatalf("validateMediaSelection: %v", err)
+				}
+				return
+			}
+			if err == nil || !strings.Contains(err.Error(), tc.wantErrSub) {
+				t.Fatalf("error = %v, want substring %q", err, tc.wantErrSub)
+			}
+		})
+	}
+}
+
 func TestListPatternsIsSorted(t *testing.T) {
 	var output bytes.Buffer
 	listPatterns(&output)
@@ -126,6 +189,16 @@ func TestBuildVideoConfigFromArgs(t *testing.T) {
 	}
 }
 
+func TestBuildVideoConfigDisabled(t *testing.T) {
+	cfg, err := buildVideoConfig(appArgs{noVideo: true})
+	if err != nil {
+		t.Fatalf("buildVideoConfig: %v", err)
+	}
+	if cfg != nil {
+		t.Fatalf("config = %+v, want nil for disabled video", cfg)
+	}
+}
+
 func TestBuildVideoConfigFromFile(t *testing.T) {
 	definition, err := flowdef.NewV210Video(
 		"5fbec3b1-1b0f-417d-9059-8b94a47197ed",