test(pulseaudio): cover codec list parsing and preferred-codec skip

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01B4mwP3msVPGx7xAeTfiFdQ

Author: b0bbywan

backend/pulseaudio/bluetooth_test.go

@@ -0,0 +1,82 @@
+package pulseaudio
+
+import (
+	"reflect"
+	"testing"
+
+	"github.com/jfreymuth/pulse/proto"
+)
+
+func TestParseBluetoothCodecs(t *testing.T) {
+	tests := []struct {
+		name     string
+		out      string
+		expected []string
+		wantErr  bool
+	}{
+		{
+			name:     "server reply",
+			out:      `[{"name":"sbc","description":"SBC"},{"name":"aptx_hd","description":"aptX HD"}]`,
+			expected: []string{"sbc", "aptx_hd"},
+		},
+		{
+			name:     "empty list",
+			out:      "[]",
+			expected: []string{},
+		},
+		{
+			name:    "garbage",
+			out:     "not json",
+			wantErr: true,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			got, err := parseBluetoothCodecs(tt.out)
+			if (err != nil) != tt.wantErr {
+				t.Fatalf("parseBluetoothCodecs() error = %v, wantErr %v", err, tt.wantErr)
+			}
+			if !tt.wantErr && !reflect.DeepEqual(got, tt.expected) {
+				t.Errorf("parseBluetoothCodecs() = %v, want %v", got, tt.expected)
+			}
+		})
+	}
+}
+
+func TestPickBluetoothCodec(t *testing.T) {
+	tests := []struct {
+		name      string
+		available []string
+		current   string
+		expected  string
+	}{
+		{"best available", []string{"sbc", "aptx", "aptx_hd"}, "sbc", "aptx_hd"},
+		{"fallback to aptx", []string{"sbc", "aptx"}, "sbc", "aptx"},
+		{"nothing better than sbc", []string{"sbc"}, "sbc", ""},
+		{"already on aptx, hd missing", []string{"sbc", "aptx"}, "aptx", ""},
+		{"already on aptx, hd offered", []string{"sbc", "aptx", "aptx_hd"}, "aptx", "aptx_hd"},
+		{"already on best", []string{"aptx_hd", "aptx"}, "aptx_hd", ""},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			if got := pickBluetoothCodec(tt.available, tt.current); got != tt.expected {
+				t.Errorf("pickBluetoothCodec(%v, %q) = %q, want %q", tt.available, tt.current, got, tt.expected)
+			}
+		})
+	}
+}
+
+func TestEnsureBluetoothCodecSkipsBest(t *testing.T) {
+	pa := &PulseAudioBackend{}
+	src := &proto.GetSourceInfoReply{
+		SourceIndex: 7,
+		Properties:  proto.PropList{"bluetooth.codec": proto.PropListString(preferredBluetoothCodecs[0])},
+	}
+
+	pa.ensureBluetoothCodec(src)
+
+	if _, attempted := pa.btCodecAttempted.Load(src.SourceIndex); attempted {
+		t.Errorf("source already on %s must not be attempted", preferredBluetoothCodecs[0])
+	}
+}