test(subsonic): pin getMusicFolders wire shape (#295)

internal/subsonic/browse_test.go

@@ -0,0 +1,41 @@
+package subsonic
+
+import (
+	"encoding/json"
+	"net/http/httptest"
+	"testing"
+)
+
+// TestGetMusicFoldersShape pins the wire shape — a single folder with id=1,
+// name "Music". Clients cache this response; breaking the shape invalidates
+// their library state.
+func TestGetMusicFoldersShape(t *testing.T) {
+	b := &browseHandlers{}
+	rec := httptest.NewRecorder()
+	req := httptest.NewRequest("GET", "/rest/getMusicFolders.view", nil)
+	b.getMusicFolders(rec, req)
+
+	var payload map[string]map[string]any
+	if err := json.Unmarshal(rec.Body.Bytes(), &payload); err != nil {
+		t.Fatalf("unmarshal: %v — body=%s", err, rec.Body)
+	}
+	inner := payload["subsonic-response"]
+	if inner["status"] != "ok" {
+		t.Fatalf("status = %v", inner["status"])
+	}
+	folders, ok := inner["musicFolders"].(map[string]any)
+	if !ok {
+		t.Fatalf("musicFolders missing: %+v", inner)
+	}
+	list, ok := folders["musicFolder"].([]any)
+	if !ok || len(list) != 1 {
+		t.Fatalf("musicFolder list = %+v", folders["musicFolder"])
+	}
+	first := list[0].(map[string]any)
+	if first["id"].(float64) != 1 {
+		t.Errorf("folder id = %v, want 1", first["id"])
+	}
+	if first["name"] != "Music" {
+		t.Errorf("folder name = %v, want Music", first["name"])
+	}
+}