test(ui): make headless gtk tests deterministic

Add testHasX11Auth() preflight check that verifies X11 authorization file exists and has a matching display entry before initializing GTK/Adwaita in requireGTKDisplayApp(). This prevents GTK from emitting 'Failed to open display' warnings to stderr in headless shells where DISPLAY is set but no X authority is configured.

- Add testHasX11Auth(): pure function inspecting XAUTHORITY env, ~/.Xauthority fallback, and parsing the binary .Xauthority format for display-number matching.
- Update requireGTKDisplayApp() to call testHasX11Auth() after testHasUsableGTKDisplay() and before EnsureAdwaitaInitialized(), so invalid/no-auth displays skip before any GTK initialization.
- Preserve existing gdk.DisplayGetDefault() == nil safety check for real-display envs.
- Add 20 pure-probe unit tests covering testHasUsableGTKDisplay (env/socket scenarios) and testHasX11Auth (auth file presence and content matching) using t.Setenv and temp dirs.

Verification: rtk go test ./internal/ui -count=1 → 198 passed, 0 failed. rtk make test → internal/ui PASS (pre-existing failure only in internal/infrastructure/webkit, unrelated).

commit: 42f0f48626f76bdf6d72bccac64a233770c048d1
author: brice · 4mo ago · 2026-06-20 09:52 UTC
committer: brice · 4mo ago · 2026-06-20 13:00 UTC
parent: 2be8535
signature: GPG VerifiedCD88F9E564E0102646FB6077A1A07C7C7C3E349D · arch-gpg Verified for the committer email

1 file · +555 -26

M internal/ui/app_browser_launch_test.go +555 -26

@@ -1,7 +1,9 @@
1	1		package ui
2	2
3	3		import (
	4	+	"bytes"
4	5		"context"
	6	+	"encoding/binary"
5	7		"errors"
6	8		"io"
7	9		"math"

@@ -79,51 +81,160 @@ func (r fakeSessionStateRepo) GetAllSnapshots(context.Context) ([]entity.Sessi
79	81
80	82		func (r *fakeSessionStateRepo) GetTotalSnapshotsSize(context.Context) (int64, error) { return 0, nil }
81	83
82		-	func testHasUsableGTKDisplay() bool {
83		-	if waylandDisplay := os.Getenv("WAYLAND_DISPLAY"); waylandDisplay != "" {
84		-	candidates := []string{waylandDisplay}
85		-	if runtimeDir := os.Getenv("XDG_RUNTIME_DIR"); runtimeDir != "" && !filepath.IsAbs(waylandDisplay) {
86		-	candidates = append([]string{filepath.Join(runtimeDir, waylandDisplay)}, candidates...)
	84	+	func testHasUsableWaylandDisplay() bool {
	85	+	waylandDisplay := os.Getenv("WAYLAND_DISPLAY")
	86	+	if waylandDisplay == "" {
	87	+	return false
	88	+	}
	89	+	candidates := []string{waylandDisplay}
	90	+	if runtimeDir := os.Getenv("XDG_RUNTIME_DIR"); runtimeDir != "" && !filepath.IsAbs(waylandDisplay) {
	91	+	candidates = append([]string{filepath.Join(runtimeDir, waylandDisplay)}, candidates...)
	92	+	}
	93	+	for _, candidate := range candidates {
	94	+	if _, err := os.Stat(candidate); err == nil {
	95	+	return true
87	96		}
88		-	for _, candidate := range candidates {
	97	+	}
	98	+	return false
	99	+	}
	100	+
	101	+	func testHasUsableX11Display() bool {
	102	+	display := os.Getenv("DISPLAY")
	103	+	if display == "" {
	104	+	return false
	105	+	}
	106	+	if strings.HasPrefix(display, ":") {
	107	+	displayNum := strings.TrimPrefix(display, ":")
	108	+	displayNum = strings.SplitN(displayNum, ".", 2)[0]
	109	+	if displayNum == "" {
	110	+	return false
	111	+	}
	112	+	x11SocketCandidates := []string{filepath.Join(os.TempDir(), ".X11-unix", "X"+displayNum)}
	113	+	if fallback := "/tmp/.X11-unix/X" + displayNum; fallback != x11SocketCandidates[0] {
	114	+	x11SocketCandidates = append(x11SocketCandidates, fallback)
	115	+	}
	116	+	for _, candidate := range x11SocketCandidates {
89	117		if _, err := os.Stat(candidate); err == nil {
90	118		return true
91	119		}
92	120		}
	121	+	return false
93	122		}
	123	+	return true // TCP display
	124	+	}
94	125
95		-	if display := os.Getenv("DISPLAY"); display != "" {
96		-	if strings.HasPrefix(display, ":") {
97		-	displayNum := strings.TrimPrefix(display, ":")
98		-	displayNum = strings.SplitN(displayNum, ".", 2)[0]
99		-	if displayNum == "" {
100		-	return false
101		-	}
102		-	x11SocketCandidates := []string{filepath.Join(os.TempDir(), ".X11-unix", "X"+displayNum)}
103		-	if fallback := "/tmp/.X11-unix/X" + displayNum; fallback != x11SocketCandidates[0] {
104		-	x11SocketCandidates = append(x11SocketCandidates, fallback)
105		-	}
106		-	for _, candidate := range x11SocketCandidates {
107		-	if _, err := os.Stat(candidate); err == nil {
108		-	return true
109		-	}
110		-	}
	126	+	func testHasUsableGTKDisplay() bool {
	127	+	return testHasUsableWaylandDisplay() \|\| testHasUsableX11Display()
	128	+	}
	129	+
	130	+	// testHasX11Auth checks whether X11 authorization is available for the current
	131	+	// DISPLAY before any GTK/Adwaita initialization. It is a pure function that
	132	+	// inspects env vars and the .Xauthority file only; no GTK calls.
	133	+	func testHasX11Auth() bool {
	134	+	display := os.Getenv("DISPLAY")
	135	+	if display == "" \|\| !strings.HasPrefix(display, ":") {
	136	+	// No DISPLAY or TCP-style display; can't check locally.
	137	+	// Let GTK try and fall through to gdk.DisplayGetDefault().
	138	+	return true
	139	+	}
	140	+
	141	+	displayNum := strings.TrimPrefix(display, ":")
	142	+	displayNum = strings.SplitN(displayNum, ".", 2)[0]
	143	+	if displayNum == "" {
	144	+	return false
	145	+	}
	146	+
	147	+	// Find the X authority file.
	148	+	authFile := os.Getenv("XAUTHORITY")
	149	+	if authFile == "" {
	150	+	home, err := os.UserHomeDir()
	151	+	if err != nil {
111	152		return false
112	153		}
113		-	return true
	154	+	authFile = filepath.Join(home, ".Xauthority")
	155	+	}
	156	+
	157	+	if _, err := os.Stat(authFile); err != nil {
	158	+	return false // No authority file; X11 auth will fail.
114	159		}
115	160
	161	+	// Parse the .Xauthority file to look for a matching display entry.
	162	+	// Format: sequence of {family(2B), addrLen(2B), addr, numLen(2B), num, nameLen(2B), name, dataLen(2B), data}
	163	+	// All multi-byte values are big-endian (network byte order).
	164	+	data, err := os.ReadFile(authFile)
	165	+	if err != nil {
	166	+	return false
	167	+	}
	168	+
	169	+	return testXauthorityHasDisplay(data, displayNum)
	170	+	}
	171	+
	172	+	func testXauthorityHasDisplay(data []byte, displayNum string) bool {
	173	+	for len(data) > 0 {
	174	+	if len(data) < 2 {
	175	+	return false
	176	+	}
	177	+	data = data[2:] // family, unused
	178	+
	179	+	_, rest, ok := testReadXauthorityField(data) // address
	180	+	if !ok {
	181	+	return false
	182	+	}
	183	+	num, rest, ok := testReadXauthorityField(rest)
	184	+	if !ok {
	185	+	return false
	186	+	}
	187	+	name, rest, ok := testReadXauthorityField(rest)
	188	+	if !ok {
	189	+	return false
	190	+	}
	191	+	cookie, rest, ok := testReadXauthorityField(rest)
	192	+	if !ok {
	193	+	return false
	194	+	}
	195	+	if string(num) == displayNum {
	196	+	return len(name) > 0 && len(cookie) > 0
	197	+	}
	198	+	data = rest
	199	+	}
116	200		return false
117	201		}
118	202
	203	+	func testReadXauthorityField(data []byte) ([]byte, []byte, bool) {
	204	+	if len(data) < 2 {
	205	+	return nil, nil, false
	206	+	}
	207	+	fieldLen := int(binary.BigEndian.Uint16(data[:2]))
	208	+	data = data[2:]
	209	+	if len(data) < fieldLen {
	210	+	return nil, nil, false
	211	+	}
	212	+	return data[:fieldLen], data[fieldLen:], true
	213	+	}
	214	+
	215	+	// testNeedsX11Auth reports whether GTK is expected to use the X11 backend,
	216	+	// meaning X11 authorization must be available. When a usable Wayland display
	217	+	// is present and GDK_BACKEND is not forced to x11, X11 auth is not required
	218	+	// because GTK will use the Wayland backend.
	219	+	func testNeedsX11Auth() bool {
	220	+	return !testHasUsableWaylandDisplay() \|\| os.Getenv("GDK_BACKEND") == "x11"
	221	+	}
	222	+
119	223		func requireGTKDisplayApp(t testing.T) gtk.Application {
120	224		t.Helper()
121		-	if !testHasUsableGTKDisplay() {
122		-	t.Skip("GTK display not available")
	225	+	hasWayland := testHasUsableWaylandDisplay()
	226	+	hasX11 := testHasUsableX11Display()
	227	+	if !hasWayland && !hasX11 {
	228	+	t.Skip("GTK display not available (no DISPLAY/WAYLAND_DISPLAY socket)")
	229	+	}
	230	+	// Only require X11 auth when the X11 backend will be used:
	231	+	// no Wayland (fallback to X11), or GDK_BACKEND explicitly set to x11.
	232	+	if testNeedsX11Auth() && !testHasX11Auth() {
	233	+	t.Skip("GTK display not available (X11 authorization unavailable)")
123	234		}
124	235		EnsureAdwaitaInitialized()
125	236		if gdk.DisplayGetDefault() == nil {
126		-	t.Skip("GTK display not available")
	237	+	t.Skip("GTK display not available (gdk.DisplayGetDefault returned nil)")
127	238		}
128	239		appID := AppID
129	240		gtkApp := gtk.NewApplication(&appID, gio.GApplicationNonUniqueValue)

@@ -133,6 +244,424 @@ func requireGTKDisplayApp(t testing.T) gtk.Application {
133	244		return gtkApp
134	245		}
135	246
	247	+	func Test_testHasUsableGTKDisplay_PureProbe(t *testing.T) {
	248	+	t.Run("no display env vars", func(t *testing.T) {
	249	+	t.Setenv("DISPLAY", "")
	250	+	t.Setenv("WAYLAND_DISPLAY", "")
	251	+	if got := testHasUsableGTKDisplay(); got {
	252	+	t.Errorf("testHasUsableGTKDisplay() = %v, want false", got)
	253	+	}
	254	+	})
	255	+
	256	+	t.Run("DISPLAY numeric without socket", func(t *testing.T) {
	257	+	t.Setenv("DISPLAY", ":99")
	258	+	t.Setenv("WAYLAND_DISPLAY", "")
	259	+	// No /tmp/.X11-unix/X99 socket exists
	260	+	if got := testHasUsableGTKDisplay(); got {
	261	+	t.Errorf("testHasUsableGTKDisplay() = %v, want false", got)
	262	+	}
	263	+	})
	264	+
	265	+	t.Run("DISPLAY with screen without socket", func(t *testing.T) {
	266	+	t.Setenv("DISPLAY", ":99.0")
	267	+	t.Setenv("WAYLAND_DISPLAY", "")
	268	+	if got := testHasUsableGTKDisplay(); got {
	269	+	t.Errorf("testHasUsableGTKDisplay() = %v, want false", got)
	270	+	}
	271	+	})
	272	+
	273	+	t.Run("DISPLAY colon only no number", func(t *testing.T) {
	274	+	t.Setenv("DISPLAY", ":")
	275	+	t.Setenv("WAYLAND_DISPLAY", "")
	276	+	if got := testHasUsableGTKDisplay(); got {
	277	+	t.Errorf("testHasUsableGTKDisplay() = %v, want false for empty display number", got)
	278	+	}
	279	+	})
	280	+
	281	+	t.Run("DISPLAY TCP always passes socket check", func(t *testing.T) {
	282	+	t.Setenv("DISPLAY", "remote-host:0")
	283	+	t.Setenv("WAYLAND_DISPLAY", "")
	284	+	if got := testHasUsableGTKDisplay(); !got {
	285	+	t.Errorf("testHasUsableGTKDisplay() = %v, want true for TCP display", got)
	286	+	}
	287	+	})
	288	+
	289	+	t.Run("DISPLAY with existing socket", func(t *testing.T) {
	290	+	t.Setenv("DISPLAY", ":0")
	291	+	t.Setenv("WAYLAND_DISPLAY", "")
	292	+	// /tmp/.X11-unix/X0 exists on this machine
	293	+	got := testHasUsableGTKDisplay()
	294	+	// We can't guarantee the socket exists in all environments,
	295	+	// but this verifies it doesn't crash.
	296	+	t.Logf("testHasUsableGTKDisplay() = %v (depends on /tmp/.X11-unix/X0)", got)
	297	+	})
	298	+
	299	+	t.Run("WAYLAND_DISPLAY with existing socket", func(t *testing.T) {
	300	+	t.Setenv("DISPLAY", "")
	301	+	t.Setenv("WAYLAND_DISPLAY", "wayland-1")
	302	+	tmpDir := t.TempDir()
	303	+	socketPath := filepath.Join(tmpDir, "wayland-1")
	304	+	if err := os.WriteFile(socketPath, nil, 0644); err != nil {
	305	+	t.Fatal(err)
	306	+	}
	307	+	// XDG_RUNTIME_DIR controls where Wayland sockets are looked up
	308	+	t.Setenv("XDG_RUNTIME_DIR", tmpDir)
	309	+	if got := testHasUsableGTKDisplay(); !got {
	310	+	t.Errorf("testHasUsableGTKDisplay() = %v, want true with existing wayland socket", got)
	311	+	}
	312	+	})
	313	+
	314	+	t.Run("WAYLAND_DISPLAY without socket", func(t *testing.T) {
	315	+	t.Setenv("DISPLAY", "")
	316	+	t.Setenv("WAYLAND_DISPLAY", "wayland-nonexistent")
	317	+	t.Setenv("XDG_RUNTIME_DIR", t.TempDir())
	318	+	if got := testHasUsableGTKDisplay(); got {
	319	+	t.Errorf("testHasUsableGTKDisplay() = %v, want false without wayland socket", got)
	320	+	}
	321	+	})
	322	+
	323	+	t.Run("WAYLAND_DISPLAY absolute path with existing socket", func(t *testing.T) {
	324	+	t.Setenv("DISPLAY", "")
	325	+	socketPath := filepath.Join(t.TempDir(), "wayland.sock")
	326	+	if err := os.WriteFile(socketPath, nil, 0644); err != nil {
	327	+	t.Fatal(err)
	328	+	}
	329	+	t.Setenv("WAYLAND_DISPLAY", socketPath)
	330	+	t.Setenv("XDG_RUNTIME_DIR", "/nonexistent") // Should be ignored for absolute paths
	331	+	if got := testHasUsableGTKDisplay(); !got {
	332	+	t.Errorf("testHasUsableGTKDisplay() = %v, want true with absolute wayland socket path", got)
	333	+	}
	334	+	})
	335	+	}
	336	+
	337	+	func Test_testHasX11Auth_PureProbe(t *testing.T) {
	338	+	t.Run("DISPLAY unset", func(t *testing.T) {
	339	+	t.Setenv("DISPLAY", "")
	340	+	t.Setenv("XAUTHORITY", "")
	341	+	if got := testHasX11Auth(); !got {
	342	+	t.Errorf("testHasX11Auth() = %v, want true when DISPLAY unset", got)
	343	+	}
	344	+	})
	345	+
	346	+	t.Run("DISPLAY TCP remote", func(t *testing.T) {
	347	+	t.Setenv("DISPLAY", "remote-host:0")
	348	+	t.Setenv("XAUTHORITY", "")
	349	+	if got := testHasX11Auth(); !got {
	350	+	t.Errorf("testHasX11Auth() = %v, want true for TCP display", got)
	351	+	}
	352	+	})
	353	+
	354	+	t.Run("DISPLAY local no auth file", func(t *testing.T) {
	355	+	t.Setenv("DISPLAY", ":0")
	356	+	t.Setenv("XAUTHORITY", "")
	357	+	// Use a temp home dir with no .Xauthority
	358	+	t.Setenv("HOME", t.TempDir())
	359	+	if got := testHasX11Auth(); got {
	360	+	t.Errorf("testHasX11Auth() = %v, want false without auth file", got)
	361	+	}
	362	+	})
	363	+
	364	+	t.Run("DISPLAY local XAUTHORITY env missing file", func(t *testing.T) {
	365	+	t.Setenv("DISPLAY", ":0")
	366	+	t.Setenv("XAUTHORITY", "/nonexistent/.Xauthority")
	367	+	if got := testHasX11Auth(); got {
	368	+	t.Errorf("testHasX11Auth() = %v, want false when XAUTHORITY file missing", got)
	369	+	}
	370	+	})
	371	+
	372	+	t.Run("DISPLAY local XAUTHORITY with matching entry", func(t *testing.T) {
	373	+	t.Setenv("DISPLAY", ":1")
	374	+	authFile := filepath.Join(t.TempDir(), ".Xauthority")
	375	+	createXauthFile(t, authFile, "1", "MIT-MAGIC-COOKIE-1", []byte{0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f, 0x10})
	376	+	t.Setenv("XAUTHORITY", authFile)
	377	+	if got := testHasX11Auth(); !got {
	378	+	t.Errorf("testHasX11Auth() = %v, want true with matching auth entry", got)
	379	+	}
	380	+	})
	381	+
	382	+	t.Run("DISPLAY local XAUTHORITY with non-matching entry", func(t *testing.T) {
	383	+	t.Setenv("DISPLAY", ":2")
	384	+	authFile := filepath.Join(t.TempDir(), ".Xauthority")
	385	+	createXauthFile(t, authFile, "0", "MIT-MAGIC-COOKIE-1", []byte{0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f, 0x10})
	386	+	t.Setenv("XAUTHORITY", authFile)
	387	+	if got := testHasX11Auth(); got {
	388	+	t.Errorf("testHasX11Auth() = %v, want false with non-matching auth entry", got)
	389	+	}
	390	+	})
	391	+
	392	+	t.Run("DISPLAY local with screen number", func(t *testing.T) {
	393	+	t.Setenv("DISPLAY", ":0.0")
	394	+	authFile := filepath.Join(t.TempDir(), ".Xauthority")
	395	+	createXauthFile(t, authFile, "0", "MIT-MAGIC-COOKIE-1", []byte{0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f, 0x10})
	396	+	t.Setenv("XAUTHORITY", authFile)
	397	+	if got := testHasX11Auth(); !got {
	398	+	t.Errorf("testHasX11Auth() = %v, want true with screen suffix stripped", got)
	399	+	}
	400	+	})
	401	+
	402	+	t.Run("DISPLAY colon only no number defaults to false", func(t *testing.T) {
	403	+	t.Setenv("DISPLAY", ":")
	404	+	t.Setenv("XAUTHORITY", "")
	405	+	if got := testHasX11Auth(); got {
	406	+	t.Errorf("testHasX11Auth() = %v, want false for empty display number", got)
	407	+	}
	408	+	})
	409	+	}
	410	+
	411	+	// writeXauthRecord appends one local-family .Xauthority record to buf with the given fields.
	412	+	// If name or data is empty, the length byte is written as zero but the field
	413	+	// data is omitted, producing a truncated record suitable for malformed tests.
	414	+	func writeXauthRecord(buf *bytes.Buffer, num, name string, data []byte) {
	415	+	// family (2 bytes, big-endian)
	416	+	familyBytes := make([]byte, 2)
	417	+	binary.BigEndian.PutUint16(familyBytes, 256)
	418	+	buf.Write(familyBytes)
	419	+
	420	+	// address
	421	+	addrLen := make([]byte, 2)
	422	+	addr := "host"
	423	+	binary.BigEndian.PutUint16(addrLen, uint16(len(addr)))
	424	+	buf.Write(addrLen)
	425	+	buf.WriteString(addr)
	426	+
	427	+	// number
	428	+	numLen := make([]byte, 2)
	429	+	binary.BigEndian.PutUint16(numLen, uint16(len(num)))
	430	+	buf.Write(numLen)
	431	+	buf.WriteString(num)
	432	+
	433	+	// name
	434	+	nameLen := make([]byte, 2)
	435	+	binary.BigEndian.PutUint16(nameLen, uint16(len(name)))
	436	+	buf.Write(nameLen)
	437	+	if name != "" {
	438	+	buf.WriteString(name)
	439	+	}
	440	+
	441	+	// data
	442	+	dLen := make([]byte, 2)
	443	+	binary.BigEndian.PutUint16(dLen, uint16(len(data)))
	444	+	buf.Write(dLen)
	445	+	if len(data) > 0 {
	446	+	buf.Write(data)
	447	+	}
	448	+	}
	449	+
	450	+	func Test_testHasX11Auth_MalformedRecords(t *testing.T) {
	451	+	t.Run("matching display with empty name field", func(t *testing.T) {
	452	+	t.Setenv("DISPLAY", ":1")
	453	+	authFile := filepath.Join(t.TempDir(), ".Xauthority")
	454	+	var buf bytes.Buffer
	455	+	writeXauthRecord(&buf, "1", "", []byte{0x01, 0x02, 0x03, 0x04})
	456	+	if err := os.WriteFile(authFile, buf.Bytes(), 0644); err != nil {
	457	+	t.Fatal(err)
	458	+	}
	459	+	t.Setenv("XAUTHORITY", authFile)
	460	+	if got := testHasX11Auth(); got {
	461	+	t.Errorf("testHasX11Auth() = %v, want false for matching display with empty name", got)
	462	+	}
	463	+	})
	464	+
	465	+	t.Run("matching display with empty data field", func(t *testing.T) {
	466	+	t.Setenv("DISPLAY", ":1")
	467	+	authFile := filepath.Join(t.TempDir(), ".Xauthority")
	468	+	var buf bytes.Buffer
	469	+	writeXauthRecord(&buf, "1", "MIT-MAGIC-COOKIE-1", nil)
	470	+	if err := os.WriteFile(authFile, buf.Bytes(), 0644); err != nil {
	471	+	t.Fatal(err)
	472	+	}
	473	+	t.Setenv("XAUTHORITY", authFile)
	474	+	if got := testHasX11Auth(); got {
	475	+	t.Errorf("testHasX11Auth() = %v, want false for matching display with empty data", got)
	476	+	}
	477	+	})
	478	+
	479	+	t.Run("truncated record after display number", func(t *testing.T) {
	480	+	t.Setenv("DISPLAY", ":1")
	481	+	authFile := filepath.Join(t.TempDir(), ".Xauthority")
	482	+	var buf bytes.Buffer
	483	+	family := make([]byte, 2)
	484	+	binary.BigEndian.PutUint16(family, 256)
	485	+	buf.Write(family)
	486	+	addr := "host"
	487	+	addrLen := make([]byte, 2)
	488	+	binary.BigEndian.PutUint16(addrLen, uint16(len(addr)))
	489	+	buf.Write(addrLen)
	490	+	buf.WriteString(addr)
	491	+	num := "1"
	492	+	numLen := make([]byte, 2)
	493	+	binary.BigEndian.PutUint16(numLen, uint16(len(num)))
	494	+	buf.Write(numLen)
	495	+	buf.WriteString(num)
	496	+	// Record ends here — no name or data fields follow.
	497	+	if err := os.WriteFile(authFile, buf.Bytes(), 0644); err != nil {
	498	+	t.Fatal(err)
	499	+	}
	500	+	t.Setenv("XAUTHORITY", authFile)
	501	+	if got := testHasX11Auth(); got {
	502	+	t.Errorf("testHasX11Auth() = %v, want false for truncated record", got)
	503	+	}
	504	+	})
	505	+
	506	+	t.Run("multiple entries with one matching and valid", func(t *testing.T) {
	507	+	t.Setenv("DISPLAY", ":3")
	508	+	authFile := filepath.Join(t.TempDir(), ".Xauthority")
	509	+	var buf bytes.Buffer
	510	+	writeXauthRecord(&buf, "0", "MIT-MAGIC-COOKIE-1", []byte{0x01, 0x02, 0x03, 0x04})
	511	+	writeXauthRecord(&buf, "1", "MIT-MAGIC-COOKIE-1", []byte{0x05, 0x06, 0x07, 0x08})
	512	+	writeXauthRecord(&buf, "3", "MIT-MAGIC-COOKIE-1", []byte{0x09, 0x0a, 0x0b, 0x0c})
	513	+	if err := os.WriteFile(authFile, buf.Bytes(), 0644); err != nil {
	514	+	t.Fatal(err)
	515	+	}
	516	+	t.Setenv("XAUTHORITY", authFile)
	517	+	if got := testHasX11Auth(); !got {
	518	+	t.Errorf("testHasX11Auth() = %v, want true for third entry matching display :3", got)
	519	+	}
	520	+	})
	521	+	}
	522	+
	523	+	func Test_testHasUsableWaylandDisplay_PureProbe(t *testing.T) {
	524	+	t.Run("no WAYLAND_DISPLAY", func(t *testing.T) {
	525	+	t.Setenv("WAYLAND_DISPLAY", "")
	526	+	if got := testHasUsableWaylandDisplay(); got {
	527	+	t.Errorf("testHasUsableWaylandDisplay() = %v, want false", got)
	528	+	}
	529	+	})
	530	+
	531	+	t.Run("WAYLAND_DISPLAY with existing socket", func(t *testing.T) {
	532	+	t.Setenv("WAYLAND_DISPLAY", "wayland-1")
	533	+	tmpDir := t.TempDir()
	534	+	socketPath := filepath.Join(tmpDir, "wayland-1")
	535	+	if err := os.WriteFile(socketPath, nil, 0644); err != nil {
	536	+	t.Fatal(err)
	537	+	}
	538	+	t.Setenv("XDG_RUNTIME_DIR", tmpDir)
	539	+	if got := testHasUsableWaylandDisplay(); !got {
	540	+	t.Errorf("testHasUsableWaylandDisplay() = %v, want true with existing wayland socket", got)
	541	+	}
	542	+	})
	543	+
	544	+	t.Run("WAYLAND_DISPLAY absolute path", func(t *testing.T) {
	545	+	socketPath := filepath.Join(t.TempDir(), "wayland.sock")
	546	+	if err := os.WriteFile(socketPath, nil, 0644); err != nil {
	547	+	t.Fatal(err)
	548	+	}
	549	+	t.Setenv("WAYLAND_DISPLAY", socketPath)
	550	+	t.Setenv("XDG_RUNTIME_DIR", "/nonexistent")
	551	+	if got := testHasUsableWaylandDisplay(); !got {
	552	+	t.Errorf("testHasUsableWaylandDisplay() = %v, want true with absolute path", got)
	553	+	}
	554	+	})
	555	+	}
	556	+
	557	+	func Test_testHasUsableX11Display_PureProbe(t *testing.T) {
	558	+	t.Run("no DISPLAY", func(t *testing.T) {
	559	+	t.Setenv("DISPLAY", "")
	560	+	if got := testHasUsableX11Display(); got {
	561	+	t.Errorf("testHasUsableX11Display() = %v, want false", got)
	562	+	}
	563	+	})
	564	+
	565	+	t.Run("DISPLAY numeric without socket", func(t *testing.T) {
	566	+	t.Setenv("DISPLAY", ":99")
	567	+	if got := testHasUsableX11Display(); got {
	568	+	t.Errorf("testHasUsableX11Display() = %v, want false", got)
	569	+	}
	570	+	})
	571	+
	572	+	t.Run("DISPLAY TCP always passes socket check", func(t *testing.T) {
	573	+	t.Setenv("DISPLAY", "remote-host:0")
	574	+	if got := testHasUsableX11Display(); !got {
	575	+	t.Errorf("testHasUsableX11Display() = %v, want true for TCP display", got)
	576	+	}
	577	+	})
	578	+	}
	579	+
	580	+	func Test_testNeedsX11Auth_PureProbe(t *testing.T) {
	581	+	t.Run("Wayland available forces no X11 auth", func(t *testing.T) {
	582	+	t.Setenv("GDK_BACKEND", "")
	583	+	t.Setenv("WAYLAND_DISPLAY", "wayland-1")
	584	+	tmpDir := t.TempDir()
	585	+	socketPath := filepath.Join(tmpDir, "wayland-1")
	586	+	if err := os.WriteFile(socketPath, nil, 0644); err != nil {
	587	+	t.Fatal(err)
	588	+	}
	589	+	t.Setenv("XDG_RUNTIME_DIR", tmpDir)
	590	+	t.Setenv("DISPLAY", ":0")
	591	+	if got := testNeedsX11Auth(); got {
	592	+	t.Errorf("testNeedsX11Auth() = %v, want false when Wayland is available and GDK_BACKEND is unset", got)
	593	+	}
	594	+	})
	595	+
	596	+	t.Run("GDK_BACKEND=x11 forces X11 auth even with Wayland", func(t *testing.T) {
	597	+	t.Setenv("GDK_BACKEND", "x11")
	598	+	t.Setenv("WAYLAND_DISPLAY", "wayland-1")
	599	+	tmpDir := t.TempDir()
	600	+	socketPath := filepath.Join(tmpDir, "wayland-1")
	601	+	if err := os.WriteFile(socketPath, nil, 0644); err != nil {
	602	+	t.Fatal(err)
	603	+	}
	604	+	t.Setenv("XDG_RUNTIME_DIR", tmpDir)
	605	+	if got := testNeedsX11Auth(); !got {
	606	+	t.Errorf("testNeedsX11Auth() = %v, want true when GDK_BACKEND=x11", got)
	607	+	}
	608	+	})
	609	+
	610	+	t.Run("No Wayland fallback needs X11 auth", func(t *testing.T) {
	611	+	t.Setenv("GDK_BACKEND", "")
	612	+	t.Setenv("WAYLAND_DISPLAY", "")
	613	+	t.Setenv("DISPLAY", ":0")
	614	+	if got := testNeedsX11Auth(); !got {
	615	+	t.Errorf("testNeedsX11Auth() = %v, want true when only X11 is available", got)
	616	+	}
	617	+	})
	618	+	}
	619	+
	620	+	// createXauthFile writes a minimal .Xauthority file with one entry.
	621	+	// family=256 (FamilyLocal), address=hostname, number=displayNum, name=proto, data=cookie.
	622	+	func createXauthFile(t *testing.T, path, displayNum, proto string, cookie []byte) {
	623	+	t.Helper()
	624	+
	625	+	hostname, err := os.Hostname()
	626	+	if err != nil {
	627	+	hostname = "localhost"
	628	+	}
	629	+
	630	+	var buf bytes.Buffer
	631	+	// family (2 bytes, big-endian) - 256 = FamilyLocal
	632	+	family := make([]byte, 2)
	633	+	binary.BigEndian.PutUint16(family, 256)
	634	+	buf.Write(family)
	635	+
	636	+	// address length + address (hostname)
	637	+	addrLen := make([]byte, 2)
	638	+	binary.BigEndian.PutUint16(addrLen, uint16(len(hostname)))
	639	+	buf.Write(addrLen)
	640	+	buf.WriteString(hostname)
	641	+
	642	+	// number length + number (display number)
	643	+	numLen := make([]byte, 2)
	644	+	binary.BigEndian.PutUint16(numLen, uint16(len(displayNum)))
	645	+	buf.Write(numLen)
	646	+	buf.WriteString(displayNum)
	647	+
	648	+	// name length + name (auth protocol)
	649	+	nameLen := make([]byte, 2)
	650	+	binary.BigEndian.PutUint16(nameLen, uint16(len(proto)))
	651	+	buf.Write(nameLen)
	652	+	buf.WriteString(proto)
	653	+
	654	+	// data length + data (auth cookie)
	655	+	dataLen := make([]byte, 2)
	656	+	binary.BigEndian.PutUint16(dataLen, uint16(len(cookie)))
	657	+	buf.Write(dataLen)
	658	+	buf.Write(cookie)
	659	+
	660	+	if err := os.WriteFile(path, buf.Bytes(), 0644); err != nil {
	661	+	t.Fatal(err)
	662	+	}
	663	+	}
	664	+
136	665		// setDependencyField uses reflection to reach unexported dependency fields for tests.
137	666		// Keep this test-only so production visibility stays narrow.
138	667		func setDependencyField(t testing.T, deps Dependencies, field string, value any) {

@@ -1,7 +1,9 @@
1		package ui	1		package ui
2			2
3		import (	3		import (
			4	+	"bytes"
4		"context"	5		"context"
			6	+	"encoding/binary"
5		"errors"	7		"errors"
6		"io"	8		"io"
7		"math"	9		"math"

@@ -79,51 +81,160 @@ func (r fakeSessionStateRepo) GetAllSnapshots(context.Context) ([]entity.Sessi
79			81
80		func (r *fakeSessionStateRepo) GetTotalSnapshotsSize(context.Context) (int64, error) { return 0, nil }	82		func (r *fakeSessionStateRepo) GetTotalSnapshotsSize(context.Context) (int64, error) { return 0, nil }
81			83
82	-	func testHasUsableGTKDisplay() bool {	84	+	func testHasUsableWaylandDisplay() bool {
83	-	if waylandDisplay := os.Getenv("WAYLAND_DISPLAY"); waylandDisplay != "" {	85	+	waylandDisplay := os.Getenv("WAYLAND_DISPLAY")
84	-	candidates := []string{waylandDisplay}	86	+	if waylandDisplay == "" {
85	-	if runtimeDir := os.Getenv("XDG_RUNTIME_DIR"); runtimeDir != "" && !filepath.IsAbs(waylandDisplay) {	87	+	return false
86	-	candidates = append([]string{filepath.Join(runtimeDir, waylandDisplay)}, candidates...)	88	+	}
			89	+	candidates := []string{waylandDisplay}
			90	+	if runtimeDir := os.Getenv("XDG_RUNTIME_DIR"); runtimeDir != "" && !filepath.IsAbs(waylandDisplay) {
			91	+	candidates = append([]string{filepath.Join(runtimeDir, waylandDisplay)}, candidates...)
			92	+	}
			93	+	for _, candidate := range candidates {
			94	+	if _, err := os.Stat(candidate); err == nil {
			95	+	return true
87		}	96		}
88	-	for _, candidate := range candidates {	97	+	}
			98	+	return false
			99	+	}
			100	+
			101	+	func testHasUsableX11Display() bool {
			102	+	display := os.Getenv("DISPLAY")
			103	+	if display == "" {
			104	+	return false
			105	+	}
			106	+	if strings.HasPrefix(display, ":") {
			107	+	displayNum := strings.TrimPrefix(display, ":")
			108	+	displayNum = strings.SplitN(displayNum, ".", 2)[0]
			109	+	if displayNum == "" {
			110	+	return false
			111	+	}
			112	+	x11SocketCandidates := []string{filepath.Join(os.TempDir(), ".X11-unix", "X"+displayNum)}
			113	+	if fallback := "/tmp/.X11-unix/X" + displayNum; fallback != x11SocketCandidates[0] {
			114	+	x11SocketCandidates = append(x11SocketCandidates, fallback)
			115	+	}
			116	+	for _, candidate := range x11SocketCandidates {
89		if _, err := os.Stat(candidate); err == nil {	117		if _, err := os.Stat(candidate); err == nil {
90		return true	118		return true
91		}	119		}
92		}	120		}
			121	+	return false
93		}	122		}
			123	+	return true // TCP display
			124	+	}
94			125
95	-	if display := os.Getenv("DISPLAY"); display != "" {	126	+	func testHasUsableGTKDisplay() bool {
96	-	if strings.HasPrefix(display, ":") {	127	+	return testHasUsableWaylandDisplay() \|\| testHasUsableX11Display()
97	-	displayNum := strings.TrimPrefix(display, ":")	128	+	}
98	-	displayNum = strings.SplitN(displayNum, ".", 2)[0]	129	+
99	-	if displayNum == "" {	130	+	// testHasX11Auth checks whether X11 authorization is available for the current
100	-	return false	131	+	// DISPLAY before any GTK/Adwaita initialization. It is a pure function that
101	-	}	132	+	// inspects env vars and the .Xauthority file only; no GTK calls.
102	-	x11SocketCandidates := []string{filepath.Join(os.TempDir(), ".X11-unix", "X"+displayNum)}	133	+	func testHasX11Auth() bool {
103	-	if fallback := "/tmp/.X11-unix/X" + displayNum; fallback != x11SocketCandidates[0] {	134	+	display := os.Getenv("DISPLAY")
104	-	x11SocketCandidates = append(x11SocketCandidates, fallback)	135	+	if display == "" \|\| !strings.HasPrefix(display, ":") {
105	-	}	136	+	// No DISPLAY or TCP-style display; can't check locally.
106	-	for _, candidate := range x11SocketCandidates {	137	+	// Let GTK try and fall through to gdk.DisplayGetDefault().
107	-	if _, err := os.Stat(candidate); err == nil {	138	+	return true
108	-	return true	139	+	}
109	-	}	140	+
110	-	}	141	+	displayNum := strings.TrimPrefix(display, ":")
			142	+	displayNum = strings.SplitN(displayNum, ".", 2)[0]
			143	+	if displayNum == "" {
			144	+	return false
			145	+	}
			146	+
			147	+	// Find the X authority file.
			148	+	authFile := os.Getenv("XAUTHORITY")
			149	+	if authFile == "" {
			150	+	home, err := os.UserHomeDir()
			151	+	if err != nil {
111		return false	152		return false
112		}	153		}
113	-	return true	154	+	authFile = filepath.Join(home, ".Xauthority")
			155	+	}
			156	+
			157	+	if _, err := os.Stat(authFile); err != nil {
			158	+	return false // No authority file; X11 auth will fail.
114		}	159		}
115			160
			161	+	// Parse the .Xauthority file to look for a matching display entry.
			162	+	// Format: sequence of {family(2B), addrLen(2B), addr, numLen(2B), num, nameLen(2B), name, dataLen(2B), data}
			163	+	// All multi-byte values are big-endian (network byte order).
			164	+	data, err := os.ReadFile(authFile)
			165	+	if err != nil {
			166	+	return false
			167	+	}
			168	+
			169	+	return testXauthorityHasDisplay(data, displayNum)
			170	+	}
			171	+
			172	+	func testXauthorityHasDisplay(data []byte, displayNum string) bool {
			173	+	for len(data) > 0 {
			174	+	if len(data) < 2 {
			175	+	return false
			176	+	}
			177	+	data = data[2:] // family, unused
			178	+
			179	+	_, rest, ok := testReadXauthorityField(data) // address
			180	+	if !ok {
			181	+	return false
			182	+	}
			183	+	num, rest, ok := testReadXauthorityField(rest)
			184	+	if !ok {
			185	+	return false
			186	+	}
			187	+	name, rest, ok := testReadXauthorityField(rest)
			188	+	if !ok {
			189	+	return false
			190	+	}
			191	+	cookie, rest, ok := testReadXauthorityField(rest)
			192	+	if !ok {
			193	+	return false
			194	+	}
			195	+	if string(num) == displayNum {
			196	+	return len(name) > 0 && len(cookie) > 0
			197	+	}
			198	+	data = rest
			199	+	}
116		return false	200		return false
117		}	201		}
118			202
			203	+	func testReadXauthorityField(data []byte) ([]byte, []byte, bool) {
			204	+	if len(data) < 2 {
			205	+	return nil, nil, false
			206	+	}
			207	+	fieldLen := int(binary.BigEndian.Uint16(data[:2]))
			208	+	data = data[2:]
			209	+	if len(data) < fieldLen {
			210	+	return nil, nil, false
			211	+	}
			212	+	return data[:fieldLen], data[fieldLen:], true
			213	+	}
			214	+
			215	+	// testNeedsX11Auth reports whether GTK is expected to use the X11 backend,
			216	+	// meaning X11 authorization must be available. When a usable Wayland display
			217	+	// is present and GDK_BACKEND is not forced to x11, X11 auth is not required
			218	+	// because GTK will use the Wayland backend.
			219	+	func testNeedsX11Auth() bool {
			220	+	return !testHasUsableWaylandDisplay() \|\| os.Getenv("GDK_BACKEND") == "x11"
			221	+	}
			222	+
119		func requireGTKDisplayApp(t testing.T) gtk.Application {	223		func requireGTKDisplayApp(t testing.T) gtk.Application {
120		t.Helper()	224		t.Helper()
121	-	if !testHasUsableGTKDisplay() {	225	+	hasWayland := testHasUsableWaylandDisplay()
122	-	t.Skip("GTK display not available")	226	+	hasX11 := testHasUsableX11Display()
			227	+	if !hasWayland && !hasX11 {
			228	+	t.Skip("GTK display not available (no DISPLAY/WAYLAND_DISPLAY socket)")
			229	+	}
			230	+	// Only require X11 auth when the X11 backend will be used:
			231	+	// no Wayland (fallback to X11), or GDK_BACKEND explicitly set to x11.
			232	+	if testNeedsX11Auth() && !testHasX11Auth() {
			233	+	t.Skip("GTK display not available (X11 authorization unavailable)")
123		}	234		}
124		EnsureAdwaitaInitialized()	235		EnsureAdwaitaInitialized()
125		if gdk.DisplayGetDefault() == nil {	236		if gdk.DisplayGetDefault() == nil {
126	-	t.Skip("GTK display not available")	237	+	t.Skip("GTK display not available (gdk.DisplayGetDefault returned nil)")
127		}	238		}
128		appID := AppID	239		appID := AppID
129		gtkApp := gtk.NewApplication(&appID, gio.GApplicationNonUniqueValue)	240		gtkApp := gtk.NewApplication(&appID, gio.GApplicationNonUniqueValue)

@@ -133,6 +244,424 @@ func requireGTKDisplayApp(t testing.T) gtk.Application {
133		return gtkApp	244		return gtkApp
134		}	245		}
135			246
			247	+	func Test_testHasUsableGTKDisplay_PureProbe(t *testing.T) {
			248	+	t.Run("no display env vars", func(t *testing.T) {
			249	+	t.Setenv("DISPLAY", "")
			250	+	t.Setenv("WAYLAND_DISPLAY", "")
			251	+	if got := testHasUsableGTKDisplay(); got {
			252	+	t.Errorf("testHasUsableGTKDisplay() = %v, want false", got)
			253	+	}
			254	+	})
			255	+
			256	+	t.Run("DISPLAY numeric without socket", func(t *testing.T) {
			257	+	t.Setenv("DISPLAY", ":99")
			258	+	t.Setenv("WAYLAND_DISPLAY", "")
			259	+	// No /tmp/.X11-unix/X99 socket exists
			260	+	if got := testHasUsableGTKDisplay(); got {
			261	+	t.Errorf("testHasUsableGTKDisplay() = %v, want false", got)
			262	+	}
			263	+	})
			264	+
			265	+	t.Run("DISPLAY with screen without socket", func(t *testing.T) {
			266	+	t.Setenv("DISPLAY", ":99.0")
			267	+	t.Setenv("WAYLAND_DISPLAY", "")
			268	+	if got := testHasUsableGTKDisplay(); got {
			269	+	t.Errorf("testHasUsableGTKDisplay() = %v, want false", got)
			270	+	}
			271	+	})
			272	+
			273	+	t.Run("DISPLAY colon only no number", func(t *testing.T) {
			274	+	t.Setenv("DISPLAY", ":")
			275	+	t.Setenv("WAYLAND_DISPLAY", "")
			276	+	if got := testHasUsableGTKDisplay(); got {
			277	+	t.Errorf("testHasUsableGTKDisplay() = %v, want false for empty display number", got)
			278	+	}
			279	+	})
			280	+
			281	+	t.Run("DISPLAY TCP always passes socket check", func(t *testing.T) {
			282	+	t.Setenv("DISPLAY", "remote-host:0")
			283	+	t.Setenv("WAYLAND_DISPLAY", "")
			284	+	if got := testHasUsableGTKDisplay(); !got {
			285	+	t.Errorf("testHasUsableGTKDisplay() = %v, want true for TCP display", got)
			286	+	}
			287	+	})
			288	+
			289	+	t.Run("DISPLAY with existing socket", func(t *testing.T) {
			290	+	t.Setenv("DISPLAY", ":0")
			291	+	t.Setenv("WAYLAND_DISPLAY", "")
			292	+	// /tmp/.X11-unix/X0 exists on this machine
			293	+	got := testHasUsableGTKDisplay()
			294	+	// We can't guarantee the socket exists in all environments,
			295	+	// but this verifies it doesn't crash.
			296	+	t.Logf("testHasUsableGTKDisplay() = %v (depends on /tmp/.X11-unix/X0)", got)
			297	+	})
			298	+
			299	+	t.Run("WAYLAND_DISPLAY with existing socket", func(t *testing.T) {
			300	+	t.Setenv("DISPLAY", "")
			301	+	t.Setenv("WAYLAND_DISPLAY", "wayland-1")
			302	+	tmpDir := t.TempDir()
			303	+	socketPath := filepath.Join(tmpDir, "wayland-1")
			304	+	if err := os.WriteFile(socketPath, nil, 0644); err != nil {
			305	+	t.Fatal(err)
			306	+	}
			307	+	// XDG_RUNTIME_DIR controls where Wayland sockets are looked up
			308	+	t.Setenv("XDG_RUNTIME_DIR", tmpDir)
			309	+	if got := testHasUsableGTKDisplay(); !got {
			310	+	t.Errorf("testHasUsableGTKDisplay() = %v, want true with existing wayland socket", got)
			311	+	}
			312	+	})
			313	+
			314	+	t.Run("WAYLAND_DISPLAY without socket", func(t *testing.T) {
			315	+	t.Setenv("DISPLAY", "")
			316	+	t.Setenv("WAYLAND_DISPLAY", "wayland-nonexistent")
			317	+	t.Setenv("XDG_RUNTIME_DIR", t.TempDir())
			318	+	if got := testHasUsableGTKDisplay(); got {
			319	+	t.Errorf("testHasUsableGTKDisplay() = %v, want false without wayland socket", got)
			320	+	}
			321	+	})
			322	+
			323	+	t.Run("WAYLAND_DISPLAY absolute path with existing socket", func(t *testing.T) {
			324	+	t.Setenv("DISPLAY", "")
			325	+	socketPath := filepath.Join(t.TempDir(), "wayland.sock")
			326	+	if err := os.WriteFile(socketPath, nil, 0644); err != nil {
			327	+	t.Fatal(err)
			328	+	}
			329	+	t.Setenv("WAYLAND_DISPLAY", socketPath)
			330	+	t.Setenv("XDG_RUNTIME_DIR", "/nonexistent") // Should be ignored for absolute paths
			331	+	if got := testHasUsableGTKDisplay(); !got {
			332	+	t.Errorf("testHasUsableGTKDisplay() = %v, want true with absolute wayland socket path", got)
			333	+	}
			334	+	})
			335	+	}
			336	+
			337	+	func Test_testHasX11Auth_PureProbe(t *testing.T) {
			338	+	t.Run("DISPLAY unset", func(t *testing.T) {
			339	+	t.Setenv("DISPLAY", "")
			340	+	t.Setenv("XAUTHORITY", "")
			341	+	if got := testHasX11Auth(); !got {
			342	+	t.Errorf("testHasX11Auth() = %v, want true when DISPLAY unset", got)
			343	+	}
			344	+	})
			345	+
			346	+	t.Run("DISPLAY TCP remote", func(t *testing.T) {
			347	+	t.Setenv("DISPLAY", "remote-host:0")
			348	+	t.Setenv("XAUTHORITY", "")
			349	+	if got := testHasX11Auth(); !got {
			350	+	t.Errorf("testHasX11Auth() = %v, want true for TCP display", got)
			351	+	}
			352	+	})
			353	+
			354	+	t.Run("DISPLAY local no auth file", func(t *testing.T) {
			355	+	t.Setenv("DISPLAY", ":0")
			356	+	t.Setenv("XAUTHORITY", "")
			357	+	// Use a temp home dir with no .Xauthority
			358	+	t.Setenv("HOME", t.TempDir())
			359	+	if got := testHasX11Auth(); got {
			360	+	t.Errorf("testHasX11Auth() = %v, want false without auth file", got)
			361	+	}
			362	+	})
			363	+
			364	+	t.Run("DISPLAY local XAUTHORITY env missing file", func(t *testing.T) {
			365	+	t.Setenv("DISPLAY", ":0")
			366	+	t.Setenv("XAUTHORITY", "/nonexistent/.Xauthority")
			367	+	if got := testHasX11Auth(); got {
			368	+	t.Errorf("testHasX11Auth() = %v, want false when XAUTHORITY file missing", got)
			369	+	}
			370	+	})
			371	+
			372	+	t.Run("DISPLAY local XAUTHORITY with matching entry", func(t *testing.T) {
			373	+	t.Setenv("DISPLAY", ":1")
			374	+	authFile := filepath.Join(t.TempDir(), ".Xauthority")
			375	+	createXauthFile(t, authFile, "1", "MIT-MAGIC-COOKIE-1", []byte{0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f, 0x10})
			376	+	t.Setenv("XAUTHORITY", authFile)
			377	+	if got := testHasX11Auth(); !got {
			378	+	t.Errorf("testHasX11Auth() = %v, want true with matching auth entry", got)
			379	+	}
			380	+	})
			381	+
			382	+	t.Run("DISPLAY local XAUTHORITY with non-matching entry", func(t *testing.T) {
			383	+	t.Setenv("DISPLAY", ":2")
			384	+	authFile := filepath.Join(t.TempDir(), ".Xauthority")
			385	+	createXauthFile(t, authFile, "0", "MIT-MAGIC-COOKIE-1", []byte{0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f, 0x10})
			386	+	t.Setenv("XAUTHORITY", authFile)
			387	+	if got := testHasX11Auth(); got {
			388	+	t.Errorf("testHasX11Auth() = %v, want false with non-matching auth entry", got)
			389	+	}
			390	+	})
			391	+
			392	+	t.Run("DISPLAY local with screen number", func(t *testing.T) {
			393	+	t.Setenv("DISPLAY", ":0.0")
			394	+	authFile := filepath.Join(t.TempDir(), ".Xauthority")
			395	+	createXauthFile(t, authFile, "0", "MIT-MAGIC-COOKIE-1", []byte{0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f, 0x10})
			396	+	t.Setenv("XAUTHORITY", authFile)
			397	+	if got := testHasX11Auth(); !got {
			398	+	t.Errorf("testHasX11Auth() = %v, want true with screen suffix stripped", got)
			399	+	}
			400	+	})
			401	+
			402	+	t.Run("DISPLAY colon only no number defaults to false", func(t *testing.T) {
			403	+	t.Setenv("DISPLAY", ":")
			404	+	t.Setenv("XAUTHORITY", "")
			405	+	if got := testHasX11Auth(); got {
			406	+	t.Errorf("testHasX11Auth() = %v, want false for empty display number", got)
			407	+	}
			408	+	})
			409	+	}
			410	+
			411	+	// writeXauthRecord appends one local-family .Xauthority record to buf with the given fields.
			412	+	// If name or data is empty, the length byte is written as zero but the field
			413	+	// data is omitted, producing a truncated record suitable for malformed tests.
			414	+	func writeXauthRecord(buf *bytes.Buffer, num, name string, data []byte) {
			415	+	// family (2 bytes, big-endian)
			416	+	familyBytes := make([]byte, 2)
			417	+	binary.BigEndian.PutUint16(familyBytes, 256)
			418	+	buf.Write(familyBytes)
			419	+
			420	+	// address
			421	+	addrLen := make([]byte, 2)
			422	+	addr := "host"
			423	+	binary.BigEndian.PutUint16(addrLen, uint16(len(addr)))
			424	+	buf.Write(addrLen)
			425	+	buf.WriteString(addr)
			426	+
			427	+	// number
			428	+	numLen := make([]byte, 2)
			429	+	binary.BigEndian.PutUint16(numLen, uint16(len(num)))
			430	+	buf.Write(numLen)
			431	+	buf.WriteString(num)
			432	+
			433	+	// name
			434	+	nameLen := make([]byte, 2)
			435	+	binary.BigEndian.PutUint16(nameLen, uint16(len(name)))
			436	+	buf.Write(nameLen)
			437	+	if name != "" {
			438	+	buf.WriteString(name)
			439	+	}
			440	+
			441	+	// data
			442	+	dLen := make([]byte, 2)
			443	+	binary.BigEndian.PutUint16(dLen, uint16(len(data)))
			444	+	buf.Write(dLen)
			445	+	if len(data) > 0 {
			446	+	buf.Write(data)
			447	+	}
			448	+	}
			449	+
			450	+	func Test_testHasX11Auth_MalformedRecords(t *testing.T) {
			451	+	t.Run("matching display with empty name field", func(t *testing.T) {
			452	+	t.Setenv("DISPLAY", ":1")
			453	+	authFile := filepath.Join(t.TempDir(), ".Xauthority")
			454	+	var buf bytes.Buffer
			455	+	writeXauthRecord(&buf, "1", "", []byte{0x01, 0x02, 0x03, 0x04})
			456	+	if err := os.WriteFile(authFile, buf.Bytes(), 0644); err != nil {
			457	+	t.Fatal(err)
			458	+	}
			459	+	t.Setenv("XAUTHORITY", authFile)
			460	+	if got := testHasX11Auth(); got {
			461	+	t.Errorf("testHasX11Auth() = %v, want false for matching display with empty name", got)
			462	+	}
			463	+	})
			464	+
			465	+	t.Run("matching display with empty data field", func(t *testing.T) {
			466	+	t.Setenv("DISPLAY", ":1")
			467	+	authFile := filepath.Join(t.TempDir(), ".Xauthority")
			468	+	var buf bytes.Buffer
			469	+	writeXauthRecord(&buf, "1", "MIT-MAGIC-COOKIE-1", nil)
			470	+	if err := os.WriteFile(authFile, buf.Bytes(), 0644); err != nil {
			471	+	t.Fatal(err)
			472	+	}
			473	+	t.Setenv("XAUTHORITY", authFile)
			474	+	if got := testHasX11Auth(); got {
			475	+	t.Errorf("testHasX11Auth() = %v, want false for matching display with empty data", got)
			476	+	}
			477	+	})
			478	+
			479	+	t.Run("truncated record after display number", func(t *testing.T) {
			480	+	t.Setenv("DISPLAY", ":1")
			481	+	authFile := filepath.Join(t.TempDir(), ".Xauthority")
			482	+	var buf bytes.Buffer
			483	+	family := make([]byte, 2)
			484	+	binary.BigEndian.PutUint16(family, 256)
			485	+	buf.Write(family)
			486	+	addr := "host"
			487	+	addrLen := make([]byte, 2)
			488	+	binary.BigEndian.PutUint16(addrLen, uint16(len(addr)))
			489	+	buf.Write(addrLen)
			490	+	buf.WriteString(addr)
			491	+	num := "1"
			492	+	numLen := make([]byte, 2)
			493	+	binary.BigEndian.PutUint16(numLen, uint16(len(num)))
			494	+	buf.Write(numLen)
			495	+	buf.WriteString(num)
			496	+	// Record ends here — no name or data fields follow.
			497	+	if err := os.WriteFile(authFile, buf.Bytes(), 0644); err != nil {
			498	+	t.Fatal(err)
			499	+	}
			500	+	t.Setenv("XAUTHORITY", authFile)
			501	+	if got := testHasX11Auth(); got {
			502	+	t.Errorf("testHasX11Auth() = %v, want false for truncated record", got)
			503	+	}
			504	+	})
			505	+
			506	+	t.Run("multiple entries with one matching and valid", func(t *testing.T) {
			507	+	t.Setenv("DISPLAY", ":3")
			508	+	authFile := filepath.Join(t.TempDir(), ".Xauthority")
			509	+	var buf bytes.Buffer
			510	+	writeXauthRecord(&buf, "0", "MIT-MAGIC-COOKIE-1", []byte{0x01, 0x02, 0x03, 0x04})
			511	+	writeXauthRecord(&buf, "1", "MIT-MAGIC-COOKIE-1", []byte{0x05, 0x06, 0x07, 0x08})
			512	+	writeXauthRecord(&buf, "3", "MIT-MAGIC-COOKIE-1", []byte{0x09, 0x0a, 0x0b, 0x0c})
			513	+	if err := os.WriteFile(authFile, buf.Bytes(), 0644); err != nil {
			514	+	t.Fatal(err)
			515	+	}
			516	+	t.Setenv("XAUTHORITY", authFile)
			517	+	if got := testHasX11Auth(); !got {
			518	+	t.Errorf("testHasX11Auth() = %v, want true for third entry matching display :3", got)
			519	+	}
			520	+	})
			521	+	}
			522	+
			523	+	func Test_testHasUsableWaylandDisplay_PureProbe(t *testing.T) {
			524	+	t.Run("no WAYLAND_DISPLAY", func(t *testing.T) {
			525	+	t.Setenv("WAYLAND_DISPLAY", "")
			526	+	if got := testHasUsableWaylandDisplay(); got {
			527	+	t.Errorf("testHasUsableWaylandDisplay() = %v, want false", got)
			528	+	}
			529	+	})
			530	+
			531	+	t.Run("WAYLAND_DISPLAY with existing socket", func(t *testing.T) {
			532	+	t.Setenv("WAYLAND_DISPLAY", "wayland-1")
			533	+	tmpDir := t.TempDir()
			534	+	socketPath := filepath.Join(tmpDir, "wayland-1")
			535	+	if err := os.WriteFile(socketPath, nil, 0644); err != nil {
			536	+	t.Fatal(err)
			537	+	}
			538	+	t.Setenv("XDG_RUNTIME_DIR", tmpDir)
			539	+	if got := testHasUsableWaylandDisplay(); !got {
			540	+	t.Errorf("testHasUsableWaylandDisplay() = %v, want true with existing wayland socket", got)
			541	+	}
			542	+	})
			543	+
			544	+	t.Run("WAYLAND_DISPLAY absolute path", func(t *testing.T) {
			545	+	socketPath := filepath.Join(t.TempDir(), "wayland.sock")
			546	+	if err := os.WriteFile(socketPath, nil, 0644); err != nil {
			547	+	t.Fatal(err)
			548	+	}
			549	+	t.Setenv("WAYLAND_DISPLAY", socketPath)
			550	+	t.Setenv("XDG_RUNTIME_DIR", "/nonexistent")
			551	+	if got := testHasUsableWaylandDisplay(); !got {
			552	+	t.Errorf("testHasUsableWaylandDisplay() = %v, want true with absolute path", got)
			553	+	}
			554	+	})
			555	+	}
			556	+
			557	+	func Test_testHasUsableX11Display_PureProbe(t *testing.T) {
			558	+	t.Run("no DISPLAY", func(t *testing.T) {
			559	+	t.Setenv("DISPLAY", "")
			560	+	if got := testHasUsableX11Display(); got {
			561	+	t.Errorf("testHasUsableX11Display() = %v, want false", got)
			562	+	}
			563	+	})
			564	+
			565	+	t.Run("DISPLAY numeric without socket", func(t *testing.T) {
			566	+	t.Setenv("DISPLAY", ":99")
			567	+	if got := testHasUsableX11Display(); got {
			568	+	t.Errorf("testHasUsableX11Display() = %v, want false", got)
			569	+	}
			570	+	})
			571	+
			572	+	t.Run("DISPLAY TCP always passes socket check", func(t *testing.T) {
			573	+	t.Setenv("DISPLAY", "remote-host:0")
			574	+	if got := testHasUsableX11Display(); !got {
			575	+	t.Errorf("testHasUsableX11Display() = %v, want true for TCP display", got)
			576	+	}
			577	+	})
			578	+	}
			579	+
			580	+	func Test_testNeedsX11Auth_PureProbe(t *testing.T) {
			581	+	t.Run("Wayland available forces no X11 auth", func(t *testing.T) {
			582	+	t.Setenv("GDK_BACKEND", "")
			583	+	t.Setenv("WAYLAND_DISPLAY", "wayland-1")
			584	+	tmpDir := t.TempDir()
			585	+	socketPath := filepath.Join(tmpDir, "wayland-1")
			586	+	if err := os.WriteFile(socketPath, nil, 0644); err != nil {
			587	+	t.Fatal(err)
			588	+	}
			589	+	t.Setenv("XDG_RUNTIME_DIR", tmpDir)
			590	+	t.Setenv("DISPLAY", ":0")
			591	+	if got := testNeedsX11Auth(); got {
			592	+	t.Errorf("testNeedsX11Auth() = %v, want false when Wayland is available and GDK_BACKEND is unset", got)
			593	+	}
			594	+	})
			595	+
			596	+	t.Run("GDK_BACKEND=x11 forces X11 auth even with Wayland", func(t *testing.T) {
			597	+	t.Setenv("GDK_BACKEND", "x11")
			598	+	t.Setenv("WAYLAND_DISPLAY", "wayland-1")
			599	+	tmpDir := t.TempDir()
			600	+	socketPath := filepath.Join(tmpDir, "wayland-1")
			601	+	if err := os.WriteFile(socketPath, nil, 0644); err != nil {
			602	+	t.Fatal(err)
			603	+	}
			604	+	t.Setenv("XDG_RUNTIME_DIR", tmpDir)
			605	+	if got := testNeedsX11Auth(); !got {
			606	+	t.Errorf("testNeedsX11Auth() = %v, want true when GDK_BACKEND=x11", got)
			607	+	}
			608	+	})
			609	+
			610	+	t.Run("No Wayland fallback needs X11 auth", func(t *testing.T) {
			611	+	t.Setenv("GDK_BACKEND", "")
			612	+	t.Setenv("WAYLAND_DISPLAY", "")
			613	+	t.Setenv("DISPLAY", ":0")
			614	+	if got := testNeedsX11Auth(); !got {
			615	+	t.Errorf("testNeedsX11Auth() = %v, want true when only X11 is available", got)
			616	+	}
			617	+	})
			618	+	}
			619	+
			620	+	// createXauthFile writes a minimal .Xauthority file with one entry.
			621	+	// family=256 (FamilyLocal), address=hostname, number=displayNum, name=proto, data=cookie.
			622	+	func createXauthFile(t *testing.T, path, displayNum, proto string, cookie []byte) {
			623	+	t.Helper()
			624	+
			625	+	hostname, err := os.Hostname()
			626	+	if err != nil {
			627	+	hostname = "localhost"
			628	+	}
			629	+
			630	+	var buf bytes.Buffer
			631	+	// family (2 bytes, big-endian) - 256 = FamilyLocal
			632	+	family := make([]byte, 2)
			633	+	binary.BigEndian.PutUint16(family, 256)
			634	+	buf.Write(family)
			635	+
			636	+	// address length + address (hostname)
			637	+	addrLen := make([]byte, 2)
			638	+	binary.BigEndian.PutUint16(addrLen, uint16(len(hostname)))
			639	+	buf.Write(addrLen)
			640	+	buf.WriteString(hostname)
			641	+
			642	+	// number length + number (display number)
			643	+	numLen := make([]byte, 2)
			644	+	binary.BigEndian.PutUint16(numLen, uint16(len(displayNum)))
			645	+	buf.Write(numLen)
			646	+	buf.WriteString(displayNum)
			647	+
			648	+	// name length + name (auth protocol)
			649	+	nameLen := make([]byte, 2)
			650	+	binary.BigEndian.PutUint16(nameLen, uint16(len(proto)))
			651	+	buf.Write(nameLen)
			652	+	buf.WriteString(proto)
			653	+
			654	+	// data length + data (auth cookie)
			655	+	dataLen := make([]byte, 2)
			656	+	binary.BigEndian.PutUint16(dataLen, uint16(len(cookie)))
			657	+	buf.Write(dataLen)
			658	+	buf.Write(cookie)
			659	+
			660	+	if err := os.WriteFile(path, buf.Bytes(), 0644); err != nil {
			661	+	t.Fatal(err)
			662	+	}
			663	+	}
			664	+
136		// setDependencyField uses reflection to reach unexported dependency fields for tests.	665		// setDependencyField uses reflection to reach unexported dependency fields for tests.
137		// Keep this test-only so production visibility stays narrow.	666		// Keep this test-only so production visibility stays narrow.
138		func setDependencyField(t testing.T, deps Dependencies, field string, value any) {	667		func setDependencyField(t testing.T, deps Dependencies, field string, value any) {