Scan: RetroDECK's saves are found

internal/presets/linux_scan_test.go

@@ -251,6 +251,43 @@ func TestEmuDeckDetection(t *testing.T) {
 	}
 }
 
+// RetroDECK keeps every system's saves in retrodeck/saves/<system>: each
+// system's folder surfaces as its own candidate, as EmuDeck's do. Asked for
+// by a Steam Deck user whose RetroDECK games the scan did not find.
+func TestRetroDECKDetection(t *testing.T) {
+	t.Setenv("XDG_DATA_HOME", "")
+	t.Setenv("XDG_CONFIG_HOME", "")
+	home := t.TempDir()
+	for _, system := range []string{"psx", "gc"} {
+		p := filepath.Join(home, "retrodeck", "saves", system)
+		if err := os.MkdirAll(p, 0o777); err != nil {
+			t.Fatal(err)
+		}
+		if err := os.WriteFile(filepath.Join(p, "game.srm"), []byte("x"), 0o666); err != nil {
+			t.Fatal(err)
+		}
+	}
+
+	sc := &Scanner{CacheFile: filepath.Join(t.TempDir(), "cache.json"), GOOS: "linux", HomeDir: home}
+	found := sc.Scan(nil)
+
+	got := map[string]string{}
+	for _, d := range found {
+		if strings.HasPrefix(d.ID, "retrodeck-") {
+			got[d.ID] = d.Name
+		}
+	}
+	if len(got) != 2 {
+		t.Fatalf("expected 2 RetroDECK discoveries, got %d: %v", len(got), got)
+	}
+	if got["retrodeck-psx"] != "RetroDECK (psx)" {
+		t.Errorf("psx entry = %q", got["retrodeck-psx"])
+	}
+	if got["retrodeck-gc"] != "RetroDECK (gc)" {
+		t.Errorf("gc entry = %q", got["retrodeck-gc"])
+	}
+}
+
 // TestPresetGlobPaths: SD-card style wildcard locations resolve through
 // filepath.Glob.
 func TestPresetGlobPaths(t *testing.T) {

internal/presets/presets.go

@@ -188,6 +188,16 @@ var presetDefs = []preset{
 			"/run/media/*/*/Emulation/saves",
 		}},
 
+	// RetroDECK keeps every system's saves in one tree as well:
+	// retrodeck/saves/<system>, in the home folder, or on an SD card when it
+	// was moved there.
+	{ID: "retrodeck", Name: "RetroDECK", Type: "emulator", IsWrapper: true,
+		LinuxPath: []string{
+			"~/retrodeck/saves",
+			"/run/media/*/retrodeck/saves",
+			"/run/media/*/*/retrodeck/saves",
+		}},
+
 	// Steam-emulator / repack wrappers (each subfolder = one game). These
 	// are Windows conventions; on Linux the same games run under Proton and
 	// their saves live in the compatdata prefix (see scanProtonCompat).