feat(session): toggle the previously active session

commit: 316c07f32b94413fef6911d9f1a5940c66d8593b
author: brice · 3mo ago · 2026-07-11 11:41 UTC
parent: e94bd47
signature: GPG VerifiedCD88F9E564E0102646FB6077A1A07C7C7C3E349D · arch-gpg Verified for the committer email

14 files · +76 -757

M internal/usecase/command/command.go +0 -1


@@ -20,7 +20,6 @@ type Context interface {
20	20		NextTab() error
21	21		PrevTab() error
22	22		BackSession() error
23		-	ForwardSession() error
24	23		Detach() error
25	24		EnterVisualMode() error
26	25		RenameSession() error


@@ -20,7 +20,6 @@ type Context interface {
20		NextTab() error	20	NextTab() error
21		PrevTab() error	21	PrevTab() error
22		BackSession() error	22	BackSession() error
23	-	ForwardSession() error
24		Detach() error	23	Detach() error
25		EnterVisualMode() error	24	EnterVisualMode() error
26		RenameSession() error	25	RenameSession() error

M internal/usecase/command/context_mock_test.go +0 -44


@@ -519,50 +519,6 @@ func (_c MockContext_FocusPaneUp_Call) RunAndReturn(run func() error) MockCont
519	519		return _c
520	520		}
521	521
522		-	// ForwardSession provides a mock function for the type MockContext
523		-	func (_mock *MockContext) ForwardSession() error {
524		-	ret := _mock.Called()
525		-
526		-	if len(ret) == 0 {
527		-	panic("no return value specified for ForwardSession")
528		-	}
529		-
530		-	var r0 error
531		-	if returnFunc, ok := ret.Get(0).(func() error); ok {
532		-	r0 = returnFunc()
533		-	} else {
534		-	r0 = ret.Error(0)
535		-	}
536		-	return r0
537		-	}
538		-
539		-	// MockContext_ForwardSession_Call is a *mock.Call that shadows Run/Return methods with type explicit version for method 'ForwardSession'
540		-	type MockContext_ForwardSession_Call struct {
541		-	*mock.Call
542		-	}
543		-
544		-	// ForwardSession is a helper method to define mock.On call
545		-	func (_e MockContext_Expecter) ForwardSession() MockContext_ForwardSession_Call {
546		-	return &MockContext_ForwardSession_Call{Call: _e.mock.On("ForwardSession")}
547		-	}
548		-
549		-	func (_c MockContext_ForwardSession_Call) Run(run func()) MockContext_ForwardSession_Call {
550		-	_c.Call.Run(func(args mock.Arguments) {
551		-	run()
552		-	})
553		-	return _c
554		-	}
555		-
556		-	func (_c MockContext_ForwardSession_Call) Return(err error) MockContext_ForwardSession_Call {
557		-	_c.Call.Return(err)
558		-	return _c
559		-	}
560		-
561		-	func (_c MockContext_ForwardSession_Call) RunAndReturn(run func() error) MockContext_ForwardSession_Call {
562		-	_c.Call.Return(run)
563		-	return _c
564		-	}
565		-
566	522		// NextTab provides a mock function for the type MockContext
567	523		func (_mock *MockContext) NextTab() error {
568	524		ret := _mock.Called()


@@ -519,50 +519,6 @@ func (_c MockContext_FocusPaneUp_Call) RunAndReturn(run func() error) MockCont
519		return _c	519	return _c
520		}	520	}
521			521
522	-	// ForwardSession provides a mock function for the type MockContext
523	-	func (_mock *MockContext) ForwardSession() error {
524	-	ret := _mock.Called()
525	-
526	-	if len(ret) == 0 {
527	-	panic("no return value specified for ForwardSession")
528	-	}
529	-
530	-	var r0 error
531	-	if returnFunc, ok := ret.Get(0).(func() error); ok {
532	-	r0 = returnFunc()
533	-	} else {
534	-	r0 = ret.Error(0)
535	-	}
536	-	return r0
537	-	}
538	-
539	-	// MockContext_ForwardSession_Call is a *mock.Call that shadows Run/Return methods with type explicit version for method 'ForwardSession'
540	-	type MockContext_ForwardSession_Call struct {
541	-	*mock.Call
542	-	}
543	-
544	-	// ForwardSession is a helper method to define mock.On call
545	-	func (_e MockContext_Expecter) ForwardSession() MockContext_ForwardSession_Call {
546	-	return &MockContext_ForwardSession_Call{Call: _e.mock.On("ForwardSession")}
547	-	}
548	-
549	-	func (_c MockContext_ForwardSession_Call) Run(run func()) MockContext_ForwardSession_Call {
550	-	_c.Call.Run(func(args mock.Arguments) {
551	-	run()
552	-	})
553	-	return _c
554	-	}
555	-
556	-	func (_c MockContext_ForwardSession_Call) Return(err error) MockContext_ForwardSession_Call {
557	-	_c.Call.Return(err)
558	-	return _c
559	-	}
560	-
561	-	func (_c MockContext_ForwardSession_Call) RunAndReturn(run func() error) MockContext_ForwardSession_Call {
562	-	_c.Call.Return(run)
563	-	return _c
564	-	}
565	-
566		// NextTab provides a mock function for the type MockContext	522	// NextTab provides a mock function for the type MockContext
567		func (_mock *MockContext) NextTab() error {	523	func (_mock *MockContext) NextTab() error {
568		ret := _mock.Called()	524	ret := _mock.Called()

M internal/usecase/command/registry.go +1 -2


@@ -22,8 +22,7 @@ func Registry() []Command {
22	22		{Slug: "focus-pane-down", Code: "FPD", Name: "Focus pane down", Desc: "Focus the pane below", Run: func(ctx Context) error { return ctx.FocusPaneDown() }},
23	23		{Slug: "next-tab", Code: "NXT", Name: "Next tab", Desc: "Switch to the next tab", Run: func(ctx Context) error { return ctx.NextTab() }},
24	24		{Slug: "previous-tab", Code: "PVT", Name: "Previous tab", Desc: "Switch to the previous tab", Run: func(ctx Context) error { return ctx.PrevTab() }},
25		-	{Slug: "back-session", Code: "BSK", Name: "Back session", Desc: "Step backward through recent-session history", Run: func(ctx Context) error { return ctx.BackSession() }},
26		-	{Slug: "forward-session", Code: "FSK", Name: "Forward session", Desc: "Step forward through recent-session history", Run: func(ctx Context) error { return ctx.ForwardSession() }},
	25	+	{Slug: "back-session", Code: "BSK", Name: "Previous session", Desc: "Toggle the previously active session", Run: func(ctx Context) error { return ctx.BackSession() }},
27	26		{Slug: "session-picker", Code: "SSP", Name: "Session picker", Desc: "Open the session picker", Run: func(ctx Context) error { return ctx.OpenSessionPicker() }},
28	27		{Slug: "visual-mode", Code: "VIS", Name: "Visual mode", Desc: "Enter visual mode", Run: func(ctx Context) error { return ctx.EnterVisualMode() }},
29	28		{Slug: "rename-session", Code: "RNS", Name: "Rename session", Desc: "Rename the session (an ephemeral session becomes named)", Run: func(ctx Context) error { return ctx.RenameSession() }},

 		{Slug: "focus-pane-down", Code: "FPD", Name: "Focus pane down", Desc: "Focus the pane below", Run: func(ctx Context) error { return ctx.FocusPaneDown() }},
 		{Slug: "next-tab", Code: "NXT", Name: "Next tab", Desc: "Switch to the next tab", Run: func(ctx Context) error { return ctx.NextTab() }},
 		{Slug: "previous-tab", Code: "PVT", Name: "Previous tab", Desc: "Switch to the previous tab", Run: func(ctx Context) error { return ctx.PrevTab() }},
-		{Slug: "back-session", Code: "BSK", Name: "Back session", Desc: "Step backward through recent-session history", Run: func(ctx Context) error { return ctx.BackSession() }},
+		{Slug: "back-session", Code: "BSK", Name: "Previous session", Desc: "Toggle the previously active session", Run: func(ctx Context) error { return ctx.BackSession() }},
-		{Slug: "forward-session", Code: "FSK", Name: "Forward session", Desc: "Step forward through recent-session history", Run: func(ctx Context) error { return ctx.ForwardSession() }},
 		{Slug: "session-picker", Code: "SSP", Name: "Session picker", Desc: "Open the session picker", Run: func(ctx Context) error { return ctx.OpenSessionPicker() }},
 		{Slug: "visual-mode", Code: "VIS", Name: "Visual mode", Desc: "Enter visual mode", Run: func(ctx Context) error { return ctx.EnterVisualMode() }},
 		{Slug: "rename-session", Code: "RNS", Name: "Rename session", Desc: "Rename the session (an ephemeral session becomes named)", Run: func(ctx Context) error { return ctx.RenameSession() }},

M internal/usecase/command/registry_test.go +1 -2


@@ -7,7 +7,7 @@ import (
7	7
8	8		func TestRegistryCodesAndSlugsAreUniqueInOrder(t *testing.T) {
9	9		commands := Registry()
10		-	wantCodes := []string{"CNT", "CNS", "CLT", "SPR", "SPL", "SPU", "SPD", "STP", "TST", "FLT", "CLP", "FPL", "FPR", "FPU", "FPD", "NXT", "PVT", "BSK", "FSK", "SSP", "VIS", "RNS", "RNT", "DET"}
	10	+	wantCodes := []string{"CNT", "CNS", "CLT", "SPR", "SPL", "SPU", "SPD", "STP", "TST", "FLT", "CLP", "FPL", "FPR", "FPU", "FPD", "NXT", "PVT", "BSK", "SSP", "VIS", "RNS", "RNT", "DET"}
11	11
12	12		if len(commands) != len(wantCodes) {
13	13		t.Fatalf("Registry() returned %d commands, want %d", len(commands), len(wantCodes))

@@ -86,7 +86,6 @@ func TestCommandRunCallsMatchingContextMethod(t *testing.T) {
86	86		{code: "NXT", expect: func(ctx *MockContext) { ctx.EXPECT().NextTab().Return(nil).Once() }},
87	87		{code: "PVT", expect: func(ctx *MockContext) { ctx.EXPECT().PrevTab().Return(nil).Once() }},
88	88		{code: "BSK", expect: func(ctx *MockContext) { ctx.EXPECT().BackSession().Return(nil).Once() }},
89		-	{code: "FSK", expect: func(ctx *MockContext) { ctx.EXPECT().ForwardSession().Return(nil).Once() }},
90	89		{code: "SSP", expect: func(ctx *MockContext) { ctx.EXPECT().OpenSessionPicker().Return(nil).Once() }},
91	90		{code: "VIS", expect: func(ctx *MockContext) { ctx.EXPECT().EnterVisualMode().Return(nil).Once() }},
92	91		{code: "RNS", expect: func(ctx *MockContext) { ctx.EXPECT().RenameSession().Return(nil).Once() }},

 func TestRegistryCodesAndSlugsAreUniqueInOrder(t *testing.T) {
 	commands := Registry()
-	wantCodes := []string{"CNT", "CNS", "CLT", "SPR", "SPL", "SPU", "SPD", "STP", "TST", "FLT", "CLP", "FPL", "FPR", "FPU", "FPD", "NXT", "PVT", "BSK", "FSK", "SSP", "VIS", "RNS", "RNT", "DET"}
+	wantCodes := []string{"CNT", "CNS", "CLT", "SPR", "SPL", "SPU", "SPD", "STP", "TST", "FLT", "CLP", "FPL", "FPR", "FPU", "FPD", "NXT", "PVT", "BSK", "SSP", "VIS", "RNS", "RNT", "DET"}
 	if len(commands) != len(wantCodes) {
 		t.Fatalf("Registry() returned %d commands, want %d", len(commands), len(wantCodes))
 		{code: "NXT", expect: func(ctx *MockContext) { ctx.EXPECT().NextTab().Return(nil).Once() }},
 		{code: "PVT", expect: func(ctx *MockContext) { ctx.EXPECT().PrevTab().Return(nil).Once() }},
 		{code: "BSK", expect: func(ctx *MockContext) { ctx.EXPECT().BackSession().Return(nil).Once() }},
-		{code: "FSK", expect: func(ctx *MockContext) { ctx.EXPECT().ForwardSession().Return(nil).Once() }},
 		{code: "SSP", expect: func(ctx *MockContext) { ctx.EXPECT().OpenSessionPicker().Return(nil).Once() }},
 		{code: "VIS", expect: func(ctx *MockContext) { ctx.EXPECT().EnterVisualMode().Return(nil).Once() }},
 		{code: "RNS", expect: func(ctx *MockContext) { ctx.EXPECT().RenameSession().Return(nil).Once() }},

M internal/usecase/daemon/client.go +11 -20


@@ -59,12 +59,9 @@ type attachedClient struct {
59	59		theme themeui.Theme
60	60		clientTheme themeui.Theme
61	61		lastCursor cursorOut
62		-	recentNav recentSessionNavigator
63		-	// historyNavMu protects historyNav and historyNavTimer. When paint needs
64		-	// several locks, take sendMu before historyNavMu, then Daemon.mu/session.mu.
65		-	historyNavMu sync.Mutex
66		-	historyNav historyNavDisplay
67		-	historyNavTimer pendingByteTimer
	62	+	// previousSession is guarded independently. It is retained through temporary
	63	+	// setSession(nil) hand-offs and cleared only on terminal teardown.
	64	+	previousSession Guarded[*session]
68	65		linkMu sync.Mutex
69	66		sendMu sync.Mutex
70	67		}

@@ -125,22 +122,12 @@ func (ac *attachedClient) initOverlays() {
125	122
126	123		func (ac attachedClient) currentSession() session { return ac.sess.Get() }
127	124
128		-	func (ac attachedClient) setSession(sess session) {
129		-	if sess == nil {
130		-	ac.clearHistoryNav()
131		-	}
132		-	ac.sess.Set(sess)
133		-	}
	125	+	func (ac attachedClient) setSession(sess session) { ac.sess.Set(sess) }
134	126
135		-	func (ac *attachedClient) clearHistoryNav() {
136		-	if ac == nil {
137		-	return
	127	+	func (ac *attachedClient) clearPreviousSession() {
	128	+	if ac != nil {
	129	+	ac.previousSession.Set(nil)
138	130		}
139		-	ac.historyNavMu.Lock()
140		-	ac.historyNav.gen++
141		-	ac.historyNavTimer.stop()
142		-	ac.historyNav.clear()
143		-	ac.historyNavMu.Unlock()
144	131		}
145	132
146	133		func (ac *attachedClient) getTheme() themeui.Theme {

@@ -435,7 +422,9 @@ func (d Daemon) detachReplacedClient(old attachedClient) {
435	422		return
436	423		}
437	424		old.cancelResizePaint()
	425	+
438	426		d.unregisterPreview(old)
	427	+	old.clearPreviousSession()
439	428		old.setSession(nil)
440	429		d.log.Info("client displaced")
441	430		// Async + bounded: a dead or wedged old client must not stall the new

@@ -554,7 +543,9 @@ func (d Daemon) clientGone(sess session, ac *attachedClient, failed ports.Tran
554	543		d.log.Info("client parked", "session", sess.name)
555	544		return
556	545		}
	546	+
557	547		d.resetScreenDefaultColors(sess)
	548	+	ac.clearPreviousSession()
558	549		if explicit {
559	550		// Synchronous so the ack is delivered before the transport closes
560	551		// (the client is actively awaiting it), but deadline-bounded so a

 	theme                 themeui.Theme
 	clientTheme           themeui.Theme
 	lastCursor            cursorOut
-	recentNav             recentSessionNavigator
+	// previousSession is guarded independently. It is retained through temporary
-	// historyNavMu protects historyNav and historyNavTimer. When paint needs
+	// setSession(nil) hand-offs and cleared only on terminal teardown.
-	// several locks, take sendMu before historyNavMu, then Daemon.mu/session.mu.
+	previousSession Guarded[*session]
-	historyNavMu    sync.Mutex
-	historyNav      historyNavDisplay
-	historyNavTimer pendingByteTimer
 	linkMu          sync.Mutex
 	sendMu          sync.Mutex
 }
 func (ac *attachedClient) currentSession() *session { return ac.sess.Get() }
-func (ac *attachedClient) setSession(sess *session) {
+func (ac *attachedClient) setSession(sess *session) { ac.sess.Set(sess) }
-	if sess == nil {
-		ac.clearHistoryNav()
-	}
-	ac.sess.Set(sess)
-}
-func (ac *attachedClient) clearHistoryNav() {
+func (ac *attachedClient) clearPreviousSession() {
-	if ac == nil {
+	if ac != nil {
-		return
+		ac.previousSession.Set(nil)
 	}
-	ac.historyNavMu.Lock()
-	ac.historyNav.gen++
-	ac.historyNavTimer.stop()
-	ac.historyNav.clear()
-	ac.historyNavMu.Unlock()
 }
 func (ac *attachedClient) getTheme() themeui.Theme {
 		return
 	}
 	old.cancelResizePaint()
 	d.unregisterPreview(old)
+	old.clearPreviousSession()
 	old.setSession(nil)
 	d.log.Info("client displaced")
 	// Async + bounded: a dead or wedged old client must not stall the new
 		d.log.Info("client parked", "session", sess.name)
 		return
 	}
 	d.resetScreenDefaultColors(sess)
+	ac.clearPreviousSession()
 	if explicit {
 		// Synchronous so the ack is delivered before the transport closes
 		// (the client is actively awaiting it), but deadline-bounded so a

M internal/usecase/daemon/input_test.go +22 -305


@@ -17,6 +17,7 @@ import (
17	17		scopy "github.com/bnema/vev/internal/usecase/copy"
18	18		"github.com/bnema/vev/internal/usecase/keys"
19	19		"github.com/bnema/vev/internal/usecase/layout"
	20	+	"github.com/bnema/vev/internal/usecase/picker"
20	21		)
21	22
22	23		// --- test doubles -----------------------------------------------------------

@@ -415,323 +416,39 @@ func TestPaletteNextPreviousSwitchActiveTab(t *testing.T) {
415	416		}
416	417		}
417	418
418		-	func TestPaletteBackForwardSession(t *testing.T) {
	419	+	func TestPaletteBackSessionTogglesPreviousSession(t *testing.T) {
419	420		d, current, ac, _, releases := newRecentNavigationTestSessions(t)
420	421		defer releaseAll(releases)
421	422		recent := d.sessions[domain.SessionID("recent")]
422		-	older := d.sessions[domain.SessionID("older")]
423	423
424		-	runPaletteCommand(t, d, current, ac, "BSK")
425		-	require.Same(t, recent, ac.currentSession())
426		-
427		-	runPaletteCommand(t, d, recent, ac, "BSK")
428		-	require.Same(t, older, ac.currentSession())
429		-
430		-	runPaletteCommand(t, d, older, ac, "FSK")
431		-	require.Same(t, recent, ac.currentSession())
432		-
433		-	runPaletteCommand(t, d, recent, ac, "FSK")
434		-	require.Same(t, current, ac.currentSession())
435		-	}
436		-
437		-	func TestPaletteBackForwardSessionBoundaries(t *testing.T) {
438		-	t.Run("forward from current does not wrap", func(t *testing.T) {
439		-	d, current, ac, _, releases := newRecentNavigationTestSessions(t)
440		-	defer releaseAll(releases)
441		-
442		-	runPaletteCommand(t, d, current, ac, "FSK")
443		-	require.Same(t, current, ac.currentSession())
444		-	})
445		-
446		-	t.Run("back with no MRU does not move", func(t *testing.T) {
447		-	p, release := newBlockingPTY(t)
448		-	defer release()
449		-	d, sess, ac, _ := newManualSessionWithPTYs(t, p)
450		-
451		-	runPaletteCommand(t, d, sess, ac, "BSK")
452		-	require.Same(t, sess, ac.currentSession())
453		-	})
454		-
455		-	t.Run("back at oldest does not wrap", func(t *testing.T) {
456		-	d, current, ac, _, releases := newRecentNavigationTestSessions(t)
457		-	defer releaseAll(releases)
458		-	older := d.sessions[domain.SessionID("older")]
459		-
460		-	runPaletteCommand(t, d, current, ac, "BSK")
	424	+	// Picker-style successful transition records its origin.
	425	+	d.switchToTarget(current, ac, picker.Target{Session: recent.id, TabIndex: -1})
	426	+	for _, sess := range []*session{current, recent, current} {
461	427		runPaletteCommand(t, d, ac.currentSession(), ac, "BSK")
462		-	require.Same(t, older, ac.currentSession())
463		-
464		-	runPaletteCommand(t, d, older, ac, "BSK")
465		-	require.Same(t, older, ac.currentSession())
466		-	})
467		-	}
468		-
469		-	func TestHistoryNavDisplay(t *testing.T) {
470		-	ids := []domain.SessionID{"current", "recent", "older"}
471		-	var h historyNavDisplay
472		-
473		-	h.set(ids, 1, 7)
474		-	ids[1] = "mutated"
475		-	require.True(t, h.active())
476		-	require.Equal(t, []domain.SessionID{domain.SessionID("current"), domain.SessionID("recent"), domain.SessionID("older")}, h.ids)
477		-	require.Equal(t, 1, h.index)
478		-	require.Equal(t, uint64(7), h.gen)
479		-
480		-	h.index = -1
481		-	require.False(t, h.active())
482		-	h.index = len(h.ids)
483		-	require.False(t, h.active())
484		-
485		-	h.clear()
486		-	require.False(t, h.active())
487		-	require.Empty(t, h.ids)
488		-	require.Zero(t, h.index)
489		-	require.Equal(t, uint64(7), h.gen)
490		-	}
491		-
492		-	func TestHistoryNavigationCommandDetectionUsesSlug(t *testing.T) {
493		-	require.True(t, isHistoryNavigationCommand("back-session"))
494		-	require.True(t, isHistoryNavigationCommand("forward-session"))
495		-	require.False(t, isHistoryNavigationCommand("BSK"))
496		-	require.False(t, isHistoryNavigationCommand("FSK"))
497		-	require.False(t, isHistoryNavigationCommand("next-tab"))
498		-	}
499		-
500		-	func TestHistoryNavActivation(t *testing.T) {
501		-	d, current, ac, sends, releases := newRecentNavigationTestSessions(t)
502		-	defer releaseAll(releases)
503		-	recent := d.sessions[domain.SessionID("recent")]
504		-	older := d.sessions[domain.SessionID("older")]
505		-
506		-	runPaletteCommand(t, d, current, ac, "BSK")
507		-	require.Same(t, recent, ac.currentSession())
508		-	requireHistoryNav(t, ac, []domain.SessionID{"current", "recent", "older"}, 1)
509		-	require.GreaterOrEqual(t, drainOutputFrames(sends), 2)
510		-
511		-	runPaletteCommand(t, d, recent, ac, "BSK")
512		-	require.Same(t, older, ac.currentSession())
513		-	requireHistoryNav(t, ac, []domain.SessionID{"current", "recent", "older"}, 2)
514		-
515		-	runPaletteCommand(t, d, older, ac, "FSK")
516		-	require.Same(t, recent, ac.currentSession())
517		-	requireHistoryNav(t, ac, []domain.SessionID{"current", "recent", "older"}, 1)
518		-	}
519		-
520		-	func TestHistoryNavBoundaryDoesNotActivate(t *testing.T) {
521		-	d, current, ac, _, releases := newRecentNavigationTestSessions(t)
522		-	defer releaseAll(releases)
523		-
524		-	runPaletteCommand(t, d, current, ac, "FSK")
525		-
526		-	require.Same(t, current, ac.currentSession())
527		-	ac.historyNavMu.Lock()
528		-	active := ac.historyNav.active()
529		-	ac.historyNavMu.Unlock()
530		-	require.False(t, active)
531		-	}
532		-
533		-	func TestHistoryNavTimeoutExpires(t *testing.T) {
534		-	d, current, ac, sends, releases := newRecentNavigationTestSessions(t)
535		-	defer releaseAll(releases)
536		-	clock := &historyNavTestClock{timers: make(chan *historyNavTestTimer, 1)}
537		-	d.clock = clock
538		-
539		-	runPaletteCommand(t, d, current, ac, "BSK")
540		-	requireHistoryNav(t, ac, []domain.SessionID{"current", "recent", "older"}, 1)
541		-	timer := <-clock.timers
542		-	drainOutputFrames(sends)
543		-	timer.fire()
544		-
545		-	require.Eventually(t, func() bool {
546		-	ac.historyNavMu.Lock()
547		-	defer ac.historyNavMu.Unlock()
548		-	return !ac.historyNav.active()
549		-	}, time.Second, time.Millisecond)
550		-	require.Eventually(t, func() bool { return drainOutputFrames(sends) > 0 }, time.Second, time.Millisecond)
	428	+	require.Same(t, sess, ac.currentSession())
	429	+	}
551	430		}
552	431
553		-	func TestHistoryNavStaleTimerCannotClearFreshActivation(t *testing.T) {
	432	+	func TestPaletteBackSessionDoesNotMoveWithoutValidTarget(t *testing.T) {
554	433		d, current, ac, _, releases := newRecentNavigationTestSessions(t)
555	434		defer releaseAll(releases)
556		-	clock := &historyNavTestClock{timers: make(chan *historyNavTestTimer, 2)}
557		-	d.clock = clock
558		-
559		-	runPaletteCommand(t, d, current, ac, "BSK")
560		-	staleTimer := <-clock.timers
561		-	ac.clearHistoryNav()
562		-	runPaletteCommand(t, d, ac.currentSession(), ac, "FSK")
563		-	<-clock.timers
564		-
565		-	staleTimer.fire()
566		-
567		-	require.Eventually(t, func() bool {
568		-	ac.historyNavMu.Lock()
569		-	defer ac.historyNavMu.Unlock()
570		-	return ac.historyNav.active() && ac.historyNav.index == 0 && ac.historyNav.gen > 1
571		-	}, time.Second, time.Millisecond)
572		-	}
573		-
574		-	func TestHistoryNavTimerStoppedOnDetachAndReplacement(t *testing.T) {
575		-	t.Run("detach stops stale timer repaint", func(t *testing.T) {
576		-	d, current, ac, sends, releases := newRecentNavigationTestSessions(t)
577		-	defer releaseAll(releases)
578		-	clock := &historyNavTestClock{timers: make(chan *historyNavTestTimer, 1)}
579		-	d.clock = clock
580		-
581		-	runPaletteCommand(t, d, current, ac, "BSK")
582		-	timer := <-clock.timers
583		-	recent := ac.currentSession()
584		-	d.clientGone(recent, ac, ac.transport(), true)
585		-	drainOutputFrames(sends)
586		-	timer.fire()
587		-
588		-	requireNoHistoryNav(t, ac)
589		-	require.Never(t, func() bool { return drainOutputFrames(sends) > 0 }, 25*time.Millisecond, time.Millisecond)
590		-	})
591		-
592		-	t.Run("replacement stops stale timer repaint", func(t *testing.T) {
593		-	d, current, ac, sends, releases := newRecentNavigationTestSessions(t)
594		-	defer releaseAll(releases)
595		-	clock := &historyNavTestClock{timers: make(chan *historyNavTestTimer, 1)}
596		-	d.clock = clock
597		-
598		-	runPaletteCommand(t, d, current, ac, "BSK")
599		-	timer := <-clock.timers
600		-	d.detachReplacedClient(ac)
601		-	drainOutputFrames(sends)
602		-	timer.fire()
603		-
604		-	requireNoHistoryNav(t, ac)
605		-	require.Never(t, func() bool { return drainOutputFrames(sends) > 0 }, 25*time.Millisecond, time.Millisecond)
606		-	})
607		-	}
608		-
609		-	func TestHistoryNavClearsOnInvalidTrailAndNonHistorySwitch(t *testing.T) {
610		-	t.Run("invalid frozen trail clears", func(t *testing.T) {
611		-	d, current, ac, _, releases := newRecentNavigationTestSessions(t)
612		-	defer releaseAll(releases)
613		-
614		-	runPaletteCommand(t, d, current, ac, "BSK")
615		-	requireHistoryNav(t, ac, []domain.SessionID{"current", "recent", "older"}, 1)
616		-	d.mu.Lock()
617		-	delete(d.sessions, domain.SessionID("older"))
618		-	d.mu.Unlock()
619		-
620		-	require.Nil(t, d.historyNavBarState(ac))
621		-	requireNoHistoryNav(t, ac)
622		-	})
623		-
624		-	t.Run("non history palette command clears frozen trail", func(t *testing.T) {
625		-	d, current, ac, _, releases := newRecentNavigationTestSessions(t)
626		-	defer releaseAll(releases)
627		-
628		-	runPaletteCommand(t, d, current, ac, "BSK")
629		-	requireHistoryNav(t, ac, []domain.SessionID{"current", "recent", "older"}, 1)
630		-	runPaletteCommand(t, d, ac.currentSession(), ac, "NXT")
631		-
632		-	requireNoHistoryNav(t, ac)
633		-	})
634		-	}
635		-
636		-	func requireHistoryNav(t testing.T, ac attachedClient, want []domain.SessionID, wantIndex int) {
637		-	t.Helper()
638		-	ac.historyNavMu.Lock()
639		-	defer ac.historyNavMu.Unlock()
640		-	require.True(t, ac.historyNav.active())
641		-	require.Equal(t, want, ac.historyNav.ids)
642		-	require.Equal(t, wantIndex, ac.historyNav.index)
643		-	}
644		-
645		-	func requireNoHistoryNav(t testing.T, ac attachedClient) {
646		-	t.Helper()
647		-	ac.historyNavMu.Lock()
648		-	defer ac.historyNavMu.Unlock()
649		-	require.False(t, ac.historyNav.active())
650		-	}
651		-
652		-	func drainOutputFrames(sends chan ports.Frame) int {
653		-	count := 0
654		-	for {
655		-	select {
656		-	case f := <-sends:
657		-	if f.Type == ports.MsgOutput {
658		-	count++
659		-	}
660		-	default:
661		-	return count
662		-	}
	435	+	for _, tc := range []struct {
	436	+	name string
	437	+	prepare func()
	438	+	}{
	439	+	{name: "no target", prepare: func() {}},
	440	+	{name: "stale target", prepare: func() { ac.previousSession.Set(&session{id: "gone"}) }},
	441	+	{name: "same session", prepare: func() { ac.previousSession.Set(current) }},
	442	+	} {
	443	+	t.Run(tc.name, func(t *testing.T) {
	444	+	ac.clearPreviousSession()
	445	+	tc.prepare()
	446	+	runPaletteCommand(t, d, current, ac, "BSK")
	447	+	require.Same(t, current, ac.currentSession())
	448	+	})
663	449		}
664	450		}
665	451
666		-	type historyNavTestClock struct {
667		-	timers chan *historyNavTestTimer
668		-	}
669		-
670		-	func (c *historyNavTestClock) Now() time.Time { return time.Time{} }
671		-
672		-	func (c *historyNavTestClock) NewTimer(time.Duration) ports.Timer {
673		-	t := &historyNavTestTimer{ch: make(chan time.Time, 1)}
674		-	c.timers <- t
675		-	return t
676		-	}
677		-
678		-	type historyNavTestTimer struct {
679		-	ch chan time.Time
680		-	}
681		-
682		-	func (t *historyNavTestTimer) C() <-chan time.Time { return t.ch }
683		-	func (t *historyNavTestTimer) Reset(time.Duration) bool { return false }
684		-	func (t *historyNavTestTimer) Stop() bool { return true }
685		-	func (t *historyNavTestTimer) fire() { t.ch <- time.Time{} }
686		-
687		-	func TestPaletteBackForwardSessionStaleTrail(t *testing.T) {
688		-	t.Run("forward skips a killed intermediate session", func(t *testing.T) {
689		-	d, current, ac, _, releases := newRecentNavigationTestSessions(t)
690		-	defer releaseAll(releases)
691		-	recent := d.sessions[domain.SessionID("recent")]
692		-	older := d.sessions[domain.SessionID("older")]
693		-
694		-	runPaletteCommand(t, d, current, ac, "BSK")
695		-	runPaletteCommand(t, d, recent, ac, "BSK")
696		-	require.Same(t, older, ac.currentSession())
697		-
698		-	d.mu.Lock()
699		-	delete(d.sessions, recent.id)
700		-	d.mu.Unlock()
701		-
702		-	runPaletteCommand(t, d, older, ac, "FSK")
703		-	require.Same(t, current, ac.currentSession())
704		-	})
705		-
706		-	t.Run("back from current refreshes newly recent sessions", func(t *testing.T) {
707		-	d, current, ac, _, releases := newRecentNavigationTestSessions(t)
708		-	defer releaseAll(releases)
709		-	p, release := newBlockingPTY(t)
710		-	defer release()
711		-	newer := &session{id: "newer", name: "newer", ctx: current.ctx, cancel: func() {}, tabs: []*tab{newTab(p, domain.Size{Cols: 80, Rows: 23})}}
712		-	newer.mruAt.Store(25)
713		-	d.mu.Lock()
714		-	d.sessions[newer.id] = newer
715		-	d.mu.Unlock()
716		-
717		-	runPaletteCommand(t, d, current, ac, "BSK")
718		-	require.Same(t, newer, ac.currentSession())
719		-	})
720		-
721		-	t.Run("failed switch does not advance navigator index", func(t *testing.T) {
722		-	d, current, ac, _, releases := newRecentNavigationTestSessions(t)
723		-	defer releaseAll(releases)
724		-	current.mu.Lock()
725		-	current.client = nil
726		-	current.mu.Unlock()
727		-
728		-	runPaletteCommand(t, d, current, ac, "BSK")
729		-
730		-	require.Same(t, current, ac.currentSession())
731		-	require.Zero(t, ac.recentNav.index)
732		-	})
733		-	}
734		-
735	452		func newRecentNavigationTestSessions(t testing.T) (Daemon, session, attachedClient, chan ports.Frame, []func()) {
736	453		t.Helper()
737	454		p1, release1 := newBlockingPTY(t)


@@ -17,6 +17,7 @@ import (
17		scopy "github.com/bnema/vev/internal/usecase/copy"	17		scopy "github.com/bnema/vev/internal/usecase/copy"
18		"github.com/bnema/vev/internal/usecase/keys"	18		"github.com/bnema/vev/internal/usecase/keys"
19		"github.com/bnema/vev/internal/usecase/layout"	19		"github.com/bnema/vev/internal/usecase/layout"
			20	+	"github.com/bnema/vev/internal/usecase/picker"
20		)	21		)
21			22
22		// --- test doubles -----------------------------------------------------------	23		// --- test doubles -----------------------------------------------------------

@@ -415,323 +416,39 @@ func TestPaletteNextPreviousSwitchActiveTab(t *testing.T) {
415		}	416		}
416		}	417		}
417			418
418	-	func TestPaletteBackForwardSession(t *testing.T) {	419	+	func TestPaletteBackSessionTogglesPreviousSession(t *testing.T) {
419		d, current, ac, _, releases := newRecentNavigationTestSessions(t)	420		d, current, ac, _, releases := newRecentNavigationTestSessions(t)
420		defer releaseAll(releases)	421		defer releaseAll(releases)
421		recent := d.sessions[domain.SessionID("recent")]	422		recent := d.sessions[domain.SessionID("recent")]
422	-	older := d.sessions[domain.SessionID("older")]
423			423
424	-	runPaletteCommand(t, d, current, ac, "BSK")	424	+	// Picker-style successful transition records its origin.
425	-	require.Same(t, recent, ac.currentSession())	425	+	d.switchToTarget(current, ac, picker.Target{Session: recent.id, TabIndex: -1})
426	-		426	+	for _, sess := range []*session{current, recent, current} {
427	-	runPaletteCommand(t, d, recent, ac, "BSK")
428	-	require.Same(t, older, ac.currentSession())
429	-
430	-	runPaletteCommand(t, d, older, ac, "FSK")
431	-	require.Same(t, recent, ac.currentSession())
432	-
433	-	runPaletteCommand(t, d, recent, ac, "FSK")
434	-	require.Same(t, current, ac.currentSession())
435	-	}
436	-
437	-	func TestPaletteBackForwardSessionBoundaries(t *testing.T) {
438	-	t.Run("forward from current does not wrap", func(t *testing.T) {
439	-	d, current, ac, _, releases := newRecentNavigationTestSessions(t)
440	-	defer releaseAll(releases)
441	-
442	-	runPaletteCommand(t, d, current, ac, "FSK")
443	-	require.Same(t, current, ac.currentSession())
444	-	})
445	-
446	-	t.Run("back with no MRU does not move", func(t *testing.T) {
447	-	p, release := newBlockingPTY(t)
448	-	defer release()
449	-	d, sess, ac, _ := newManualSessionWithPTYs(t, p)
450	-
451	-	runPaletteCommand(t, d, sess, ac, "BSK")
452	-	require.Same(t, sess, ac.currentSession())
453	-	})
454	-
455	-	t.Run("back at oldest does not wrap", func(t *testing.T) {
456	-	d, current, ac, _, releases := newRecentNavigationTestSessions(t)
457	-	defer releaseAll(releases)
458	-	older := d.sessions[domain.SessionID("older")]
459	-
460	-	runPaletteCommand(t, d, current, ac, "BSK")
461		runPaletteCommand(t, d, ac.currentSession(), ac, "BSK")	427		runPaletteCommand(t, d, ac.currentSession(), ac, "BSK")
462	-	require.Same(t, older, ac.currentSession())	428	+	require.Same(t, sess, ac.currentSession())
463	-		429	+	}
464	-	runPaletteCommand(t, d, older, ac, "BSK")
465	-	require.Same(t, older, ac.currentSession())
466	-	})
467	-	}
468	-
469	-	func TestHistoryNavDisplay(t *testing.T) {
470	-	ids := []domain.SessionID{"current", "recent", "older"}
471	-	var h historyNavDisplay
472	-
473	-	h.set(ids, 1, 7)
474	-	ids[1] = "mutated"
475	-	require.True(t, h.active())
476	-	require.Equal(t, []domain.SessionID{domain.SessionID("current"), domain.SessionID("recent"), domain.SessionID("older")}, h.ids)
477	-	require.Equal(t, 1, h.index)
478	-	require.Equal(t, uint64(7), h.gen)
479	-
480	-	h.index = -1
481	-	require.False(t, h.active())
482	-	h.index = len(h.ids)
483	-	require.False(t, h.active())
484	-
485	-	h.clear()
486	-	require.False(t, h.active())
487	-	require.Empty(t, h.ids)
488	-	require.Zero(t, h.index)
489	-	require.Equal(t, uint64(7), h.gen)
490	-	}
491	-
492	-	func TestHistoryNavigationCommandDetectionUsesSlug(t *testing.T) {
493	-	require.True(t, isHistoryNavigationCommand("back-session"))
494	-	require.True(t, isHistoryNavigationCommand("forward-session"))
495	-	require.False(t, isHistoryNavigationCommand("BSK"))
496	-	require.False(t, isHistoryNavigationCommand("FSK"))
497	-	require.False(t, isHistoryNavigationCommand("next-tab"))
498	-	}
499	-
500	-	func TestHistoryNavActivation(t *testing.T) {
501	-	d, current, ac, sends, releases := newRecentNavigationTestSessions(t)
502	-	defer releaseAll(releases)
503	-	recent := d.sessions[domain.SessionID("recent")]
504	-	older := d.sessions[domain.SessionID("older")]
505	-
506	-	runPaletteCommand(t, d, current, ac, "BSK")
507	-	require.Same(t, recent, ac.currentSession())
508	-	requireHistoryNav(t, ac, []domain.SessionID{"current", "recent", "older"}, 1)
509	-	require.GreaterOrEqual(t, drainOutputFrames(sends), 2)
510	-
511	-	runPaletteCommand(t, d, recent, ac, "BSK")
512	-	require.Same(t, older, ac.currentSession())
513	-	requireHistoryNav(t, ac, []domain.SessionID{"current", "recent", "older"}, 2)
514	-
515	-	runPaletteCommand(t, d, older, ac, "FSK")
516	-	require.Same(t, recent, ac.currentSession())
517	-	requireHistoryNav(t, ac, []domain.SessionID{"current", "recent", "older"}, 1)
518	-	}
519	-
520	-	func TestHistoryNavBoundaryDoesNotActivate(t *testing.T) {
521	-	d, current, ac, _, releases := newRecentNavigationTestSessions(t)
522	-	defer releaseAll(releases)
523	-
524	-	runPaletteCommand(t, d, current, ac, "FSK")
525	-
526	-	require.Same(t, current, ac.currentSession())
527	-	ac.historyNavMu.Lock()
528	-	active := ac.historyNav.active()
529	-	ac.historyNavMu.Unlock()
530	-	require.False(t, active)
531	-	}
532	-
533	-	func TestHistoryNavTimeoutExpires(t *testing.T) {
534	-	d, current, ac, sends, releases := newRecentNavigationTestSessions(t)
535	-	defer releaseAll(releases)
536	-	clock := &historyNavTestClock{timers: make(chan *historyNavTestTimer, 1)}
537	-	d.clock = clock
538	-
539	-	runPaletteCommand(t, d, current, ac, "BSK")
540	-	requireHistoryNav(t, ac, []domain.SessionID{"current", "recent", "older"}, 1)
541	-	timer := <-clock.timers
542	-	drainOutputFrames(sends)
543	-	timer.fire()
544	-
545	-	require.Eventually(t, func() bool {
546	-	ac.historyNavMu.Lock()
547	-	defer ac.historyNavMu.Unlock()
548	-	return !ac.historyNav.active()
549	-	}, time.Second, time.Millisecond)
550	-	require.Eventually(t, func() bool { return drainOutputFrames(sends) > 0 }, time.Second, time.Millisecond)
551		}	430		}
552			431
553	-	func TestHistoryNavStaleTimerCannotClearFreshActivation(t *testing.T) {	432	+	func TestPaletteBackSessionDoesNotMoveWithoutValidTarget(t *testing.T) {
554		d, current, ac, _, releases := newRecentNavigationTestSessions(t)	433		d, current, ac, _, releases := newRecentNavigationTestSessions(t)
555		defer releaseAll(releases)	434		defer releaseAll(releases)
556	-	clock := &historyNavTestClock{timers: make(chan *historyNavTestTimer, 2)}	435	+	for _, tc := range []struct {
557	-	d.clock = clock	436	+	name string
558	-		437	+	prepare func()
559	-	runPaletteCommand(t, d, current, ac, "BSK")	438	+	}{
560	-	staleTimer := <-clock.timers	439	+	{name: "no target", prepare: func() {}},
561	-	ac.clearHistoryNav()	440	+	{name: "stale target", prepare: func() { ac.previousSession.Set(&session{id: "gone"}) }},
562	-	runPaletteCommand(t, d, ac.currentSession(), ac, "FSK")	441	+	{name: "same session", prepare: func() { ac.previousSession.Set(current) }},
563	-	<-clock.timers	442	+	} {
564	-		443	+	t.Run(tc.name, func(t *testing.T) {
565	-	staleTimer.fire()	444	+	ac.clearPreviousSession()
566	-		445	+	tc.prepare()
567	-	require.Eventually(t, func() bool {	446	+	runPaletteCommand(t, d, current, ac, "BSK")
568	-	ac.historyNavMu.Lock()	447	+	require.Same(t, current, ac.currentSession())
569	-	defer ac.historyNavMu.Unlock()	448	+	})
570	-	return ac.historyNav.active() && ac.historyNav.index == 0 && ac.historyNav.gen > 1
571	-	}, time.Second, time.Millisecond)
572	-	}
573	-
574	-	func TestHistoryNavTimerStoppedOnDetachAndReplacement(t *testing.T) {
575	-	t.Run("detach stops stale timer repaint", func(t *testing.T) {
576	-	d, current, ac, sends, releases := newRecentNavigationTestSessions(t)
577	-	defer releaseAll(releases)
578	-	clock := &historyNavTestClock{timers: make(chan *historyNavTestTimer, 1)}
579	-	d.clock = clock
580	-
581	-	runPaletteCommand(t, d, current, ac, "BSK")
582	-	timer := <-clock.timers
583	-	recent := ac.currentSession()
584	-	d.clientGone(recent, ac, ac.transport(), true)
585	-	drainOutputFrames(sends)
586	-	timer.fire()
587	-
588	-	requireNoHistoryNav(t, ac)
589	-	require.Never(t, func() bool { return drainOutputFrames(sends) > 0 }, 25*time.Millisecond, time.Millisecond)
590	-	})
591	-
592	-	t.Run("replacement stops stale timer repaint", func(t *testing.T) {
593	-	d, current, ac, sends, releases := newRecentNavigationTestSessions(t)
594	-	defer releaseAll(releases)
595	-	clock := &historyNavTestClock{timers: make(chan *historyNavTestTimer, 1)}
596	-	d.clock = clock
597	-
598	-	runPaletteCommand(t, d, current, ac, "BSK")
599	-	timer := <-clock.timers
600	-	d.detachReplacedClient(ac)
601	-	drainOutputFrames(sends)
602	-	timer.fire()
603	-
604	-	requireNoHistoryNav(t, ac)
605	-	require.Never(t, func() bool { return drainOutputFrames(sends) > 0 }, 25*time.Millisecond, time.Millisecond)
606	-	})
607	-	}
608	-
609	-	func TestHistoryNavClearsOnInvalidTrailAndNonHistorySwitch(t *testing.T) {
610	-	t.Run("invalid frozen trail clears", func(t *testing.T) {
611	-	d, current, ac, _, releases := newRecentNavigationTestSessions(t)
612	-	defer releaseAll(releases)
613	-
614	-	runPaletteCommand(t, d, current, ac, "BSK")
615	-	requireHistoryNav(t, ac, []domain.SessionID{"current", "recent", "older"}, 1)
616	-	d.mu.Lock()
617	-	delete(d.sessions, domain.SessionID("older"))
618	-	d.mu.Unlock()
619	-
620	-	require.Nil(t, d.historyNavBarState(ac))
621	-	requireNoHistoryNav(t, ac)
622	-	})
623	-
624	-	t.Run("non history palette command clears frozen trail", func(t *testing.T) {
625	-	d, current, ac, _, releases := newRecentNavigationTestSessions(t)
626	-	defer releaseAll(releases)
627	-
628	-	runPaletteCommand(t, d, current, ac, "BSK")
629	-	requireHistoryNav(t, ac, []domain.SessionID{"current", "recent", "older"}, 1)
630	-	runPaletteCommand(t, d, ac.currentSession(), ac, "NXT")
631	-
632	-	requireNoHistoryNav(t, ac)
633	-	})
634	-	}
635	-
636	-	func requireHistoryNav(t testing.T, ac attachedClient, want []domain.SessionID, wantIndex int) {
637	-	t.Helper()
638	-	ac.historyNavMu.Lock()
639	-	defer ac.historyNavMu.Unlock()
640	-	require.True(t, ac.historyNav.active())
641	-	require.Equal(t, want, ac.historyNav.ids)
642	-	require.Equal(t, wantIndex, ac.historyNav.index)
643	-	}
644	-
645	-	func requireNoHistoryNav(t testing.T, ac attachedClient) {
646	-	t.Helper()
647	-	ac.historyNavMu.Lock()
648	-	defer ac.historyNavMu.Unlock()
649	-	require.False(t, ac.historyNav.active())
650	-	}
651	-
652	-	func drainOutputFrames(sends chan ports.Frame) int {
653	-	count := 0
654	-	for {
655	-	select {
656	-	case f := <-sends:
657	-	if f.Type == ports.MsgOutput {
658	-	count++
659	-	}
660	-	default:
661	-	return count
662	-	}
663		}	449		}
664		}	450		}
665			451
666	-	type historyNavTestClock struct {
667	-	timers chan *historyNavTestTimer
668	-	}
669	-
670	-	func (c *historyNavTestClock) Now() time.Time { return time.Time{} }
671	-
672	-	func (c *historyNavTestClock) NewTimer(time.Duration) ports.Timer {
673	-	t := &historyNavTestTimer{ch: make(chan time.Time, 1)}
674	-	c.timers <- t
675	-	return t
676	-	}
677	-
678	-	type historyNavTestTimer struct {
679	-	ch chan time.Time
680	-	}
681	-
682	-	func (t *historyNavTestTimer) C() <-chan time.Time { return t.ch }
683	-	func (t *historyNavTestTimer) Reset(time.Duration) bool { return false }
684	-	func (t *historyNavTestTimer) Stop() bool { return true }
685	-	func (t *historyNavTestTimer) fire() { t.ch <- time.Time{} }
686	-
687	-	func TestPaletteBackForwardSessionStaleTrail(t *testing.T) {
688	-	t.Run("forward skips a killed intermediate session", func(t *testing.T) {
689	-	d, current, ac, _, releases := newRecentNavigationTestSessions(t)
690	-	defer releaseAll(releases)
691	-	recent := d.sessions[domain.SessionID("recent")]
692	-	older := d.sessions[domain.SessionID("older")]
693	-
694	-	runPaletteCommand(t, d, current, ac, "BSK")
695	-	runPaletteCommand(t, d, recent, ac, "BSK")
696	-	require.Same(t, older, ac.currentSession())
697	-
698	-	d.mu.Lock()
699	-	delete(d.sessions, recent.id)
700	-	d.mu.Unlock()
701	-
702	-	runPaletteCommand(t, d, older, ac, "FSK")
703	-	require.Same(t, current, ac.currentSession())
704	-	})
705	-
706	-	t.Run("back from current refreshes newly recent sessions", func(t *testing.T) {
707	-	d, current, ac, _, releases := newRecentNavigationTestSessions(t)
708	-	defer releaseAll(releases)
709	-	p, release := newBlockingPTY(t)
710	-	defer release()
711	-	newer := &session{id: "newer", name: "newer", ctx: current.ctx, cancel: func() {}, tabs: []*tab{newTab(p, domain.Size{Cols: 80, Rows: 23})}}
712	-	newer.mruAt.Store(25)
713	-	d.mu.Lock()
714	-	d.sessions[newer.id] = newer
715	-	d.mu.Unlock()
716	-
717	-	runPaletteCommand(t, d, current, ac, "BSK")
718	-	require.Same(t, newer, ac.currentSession())
719	-	})
720	-
721	-	t.Run("failed switch does not advance navigator index", func(t *testing.T) {
722	-	d, current, ac, _, releases := newRecentNavigationTestSessions(t)
723	-	defer releaseAll(releases)
724	-	current.mu.Lock()
725	-	current.client = nil
726	-	current.mu.Unlock()
727	-
728	-	runPaletteCommand(t, d, current, ac, "BSK")
729	-
730	-	require.Same(t, current, ac.currentSession())
731	-	require.Zero(t, ac.recentNav.index)
732	-	})
733	-	}
734	-
735		func newRecentNavigationTestSessions(t testing.T) (Daemon, session, attachedClient, chan ports.Frame, []func()) {	452		func newRecentNavigationTestSessions(t testing.T) (Daemon, session, attachedClient, chan ports.Frame, []func()) {
736		t.Helper()	453		t.Helper()
737		p1, release1 := newBlockingPTY(t)	454		p1, release1 := newBlockingPTY(t)

M internal/usecase/daemon/palette.go +1 -13


@@ -141,9 +141,6 @@ func (d Daemon) handlePaletteInput(ac attachedClient, data []byte) {
141	141		ac.overlays.paletteMu.Unlock()
142	142
143	143		if run && ok {
144		-	if !isHistoryNavigationCommand(cmd.Slug) {
145		-	d.clearHistoryNav(ac)
146		-	}
147	144		if err := cmd.Run(paletteExec{d: d, sess: sess, ac: ac}); err != nil {
148	145		sess.mu.Lock()
149	146		name := sess.name

@@ -159,10 +156,6 @@ func (d Daemon) handlePaletteInput(ac attachedClient, data []byte) {
159	156		}
160	157		}
161	158
162		-	func isHistoryNavigationCommand(slug string) bool {
163		-	return slug == "back-session" \|\| slug == "forward-session"
164		-	}
165		-
166	159		type paletteExec struct {
167	160		d *Daemon
168	161		sess *session

@@ -253,12 +246,7 @@ func (e paletteExec) ToggleFloatingPane() error {
253	246		}
254	247
255	248		func (e paletteExec) BackSession() error {
256		-	e.d.navigateRecentSession(e.sess, e.ac, 1)
257		-	return nil
258		-	}
259		-
260		-	func (e paletteExec) ForwardSession() error {
261		-	e.d.navigateRecentSession(e.sess, e.ac, -1)
	249	+	e.d.backSession(e.sess, e.ac)
262	250		return nil
263	251		}
264	252

 	ac.overlays.paletteMu.Unlock()
 	if run && ok {
-		if !isHistoryNavigationCommand(cmd.Slug) {
-			d.clearHistoryNav(ac)
-		}
 		if err := cmd.Run(paletteExec{d: d, sess: sess, ac: ac}); err != nil {
 			sess.mu.Lock()
 			name := sess.name
 	}
 }
-func isHistoryNavigationCommand(slug string) bool {
-	return slug == "back-session" || slug == "forward-session"
-}
 type paletteExec struct {
 	d    *Daemon
 	sess *session
 }
 func (e paletteExec) BackSession() error {
-	e.d.navigateRecentSession(e.sess, e.ac, 1)
+	e.d.backSession(e.sess, e.ac)
-	return nil
-}
-func (e paletteExec) ForwardSession() error {
-	e.d.navigateRecentSession(e.sess, e.ac, -1)
 	return nil
 }

M internal/usecase/daemon/palette_test.go +2 -2


@@ -138,12 +138,12 @@ func TestPaletteRecentCommandsNewestFirstThenRegistryOrder(t *testing.T) {
138	138		for i, cmd := range commands {
139	139		codes[i] = cmd.Code
140	140		}
141		-	require.Equal(t, []string{"SSP", "NXT", "CNT", "CNS", "CLT", "SPR", "SPL", "SPU", "SPD", "STP", "TST", "FLT", "CLP", "FPL", "FPR", "FPU", "FPD", "PVT", "BSK", "FSK", "VIS", "RNS", "RNT", "DET"}, codes)
	141	+	require.Equal(t, []string{"SSP", "NXT", "CNT", "CNS", "CLT", "SPR", "SPL", "SPU", "SPD", "STP", "TST", "FLT", "CLP", "FPL", "FPR", "FPU", "FPD", "PVT", "BSK", "VIS", "RNS", "RNT", "DET"}, codes)
142	142		}
143	143
144	144		func TestPaletteRecencyCanBeUpdatedConcurrently(t *testing.T) {
145	145		d := &Daemon{}
146		-	codes := []string{"CNT", "CNS", "CLT", "SPR", "SPL", "SPU", "SPD", "STP", "TST", "FLT", "CLP", "FPL", "FPR", "FPU", "FPD", "NXT", "PVT", "BSK", "FSK", "SSP", "VIS", "RNS", "RNT", "DET"}
	146	+	codes := []string{"CNT", "CNS", "CLT", "SPR", "SPL", "SPU", "SPD", "STP", "TST", "FLT", "CLP", "FPL", "FPR", "FPU", "FPD", "NXT", "PVT", "BSK", "SSP", "VIS", "RNS", "RNT", "DET"}
147	147
148	148		var wg sync.WaitGroup
149	149		for range 50 {


@@ -138,12 +138,12 @@ func TestPaletteRecentCommandsNewestFirstThenRegistryOrder(t *testing.T) {
138		for i, cmd := range commands {	138		for i, cmd := range commands {
139		codes[i] = cmd.Code	139		codes[i] = cmd.Code
140		}	140		}
141	-	require.Equal(t, []string{"SSP", "NXT", "CNT", "CNS", "CLT", "SPR", "SPL", "SPU", "SPD", "STP", "TST", "FLT", "CLP", "FPL", "FPR", "FPU", "FPD", "PVT", "BSK", "FSK", "VIS", "RNS", "RNT", "DET"}, codes)	141	+	require.Equal(t, []string{"SSP", "NXT", "CNT", "CNS", "CLT", "SPR", "SPL", "SPU", "SPD", "STP", "TST", "FLT", "CLP", "FPL", "FPR", "FPU", "FPD", "PVT", "BSK", "VIS", "RNS", "RNT", "DET"}, codes)
142		}	142		}
143			143
144		func TestPaletteRecencyCanBeUpdatedConcurrently(t *testing.T) {	144		func TestPaletteRecencyCanBeUpdatedConcurrently(t *testing.T) {
145		d := &Daemon{}	145		d := &Daemon{}
146	-	codes := []string{"CNT", "CNS", "CLT", "SPR", "SPL", "SPU", "SPD", "STP", "TST", "FLT", "CLP", "FPL", "FPR", "FPU", "FPD", "NXT", "PVT", "BSK", "FSK", "SSP", "VIS", "RNS", "RNT", "DET"}	146	+	codes := []string{"CNT", "CNS", "CLT", "SPR", "SPL", "SPU", "SPD", "STP", "TST", "FLT", "CLP", "FPL", "FPR", "FPU", "FPD", "NXT", "PVT", "BSK", "SSP", "VIS", "RNS", "RNT", "DET"}
147			147
148		var wg sync.WaitGroup	148		var wg sync.WaitGroup
149		for range 50 {	149		for range 50 {

M internal/usecase/daemon/picker.go +6 -1


@@ -354,7 +354,6 @@ func (d Daemon) sessionByID(id domain.SessionID) session {
354	354		}
355	355
356	356		func (d Daemon) switchToTarget(sess session, ac *attachedClient, target picker.Target) {
357		-	d.clearHistoryNav(ac)
358	357		if target.Stopped {
359	358		d.resumeStoppedAndSwitch(sess, ac, target)
360	359		return

@@ -377,7 +376,9 @@ func (d Daemon) switchToTarget(sess session, ac *attachedClient, target picker
377	376		return
378	377		}
379	378		if old != nil && old != ac {
	379	+
380	380		d.unregisterPreview(old)
	381	+	old.clearPreviousSession()
381	382		old.setSession(nil)
382	383		d.notifyDetachedAsync(old, ports.ReasonDetach)
383	384		}

@@ -409,8 +410,10 @@ func (d Daemon) stealClientForTarget(from session, ac *attachedClient, targetS
409	410		targetSess.active = target.TabIndex
410	411		}
411	412		targetSess.mu.Unlock()
	413	+
412	414		d.touchMRU(targetSess)
413	415		ac.setSession(targetSess)
	416	+	ac.recordPreviousSession(from)
414	417		d.mu.Unlock()
415	418		return old
416	419		}

@@ -445,8 +448,10 @@ func (d Daemon) resumeStoppedAndSwitch(from session, ac *attachedClient, targe
445	448		targetSess.mu.Lock()
446	449		targetSess.client = ac
447	450		targetSess.mu.Unlock()
	451	+
448	452		d.touchMRU(targetSess)
449	453		ac.setSession(targetSess)
	454	+	ac.recordPreviousSession(from)
450	455		d.mu.Unlock()
451	456		d.firstPaint(targetSess, ac, ac.size)
452	457		}

 }
 func (d *Daemon) switchToTarget(sess *session, ac *attachedClient, target picker.Target) {
-	d.clearHistoryNav(ac)
 	if target.Stopped {
 		d.resumeStoppedAndSwitch(sess, ac, target)
 		return
 		return
 	}
 	if old != nil && old != ac {
 		d.unregisterPreview(old)
+		old.clearPreviousSession()
 		old.setSession(nil)
 		d.notifyDetachedAsync(old, ports.ReasonDetach)
 	}
 		targetSess.active = target.TabIndex
 	}
 	targetSess.mu.Unlock()
 	d.touchMRU(targetSess)
 	ac.setSession(targetSess)
+	ac.recordPreviousSession(from)
 	d.mu.Unlock()
 	return old
 }
 	targetSess.mu.Lock()
 	targetSess.client = ac
 	targetSess.mu.Unlock()
 	d.touchMRU(targetSess)
 	ac.setSession(targetSess)
+	ac.recordPreviousSession(from)
 	d.mu.Unlock()
 	d.firstPaint(targetSess, ac, ac.size)
 }

D internal/usecase/daemon/recent_nav.go +0 -163

@@ -1,163 +0,0 @@
1	-	package daemon
2	-
3	-	import (
4	-	"time"
5	-
6	-	"github.com/bnema/vev/internal/domain"
7	-	"github.com/bnema/vev/internal/ports"
8	-	"github.com/bnema/vev/internal/usecase/picker"
9	-	)
10	-
11	-	const historyNavDisplayTimeout = 1500 * time.Millisecond
12	-
13	-	type recentSessionNavigator struct {
14	-	ids []domain.SessionID
15	-	index int
16	-	}
17	-
18	-	type historyNavDisplay struct {
19	-	ids []domain.SessionID
20	-	index int
21	-	gen uint64
22	-	}
23	-
24	-	func (h *historyNavDisplay) set(ids []domain.SessionID, index int, gen uint64) {
25	-	h.ids = append(h.ids[:0], ids...)
26	-	h.index = index
27	-	h.gen = gen
28	-	}
29	-
30	-	func (h *historyNavDisplay) clear() {
31	-	h.ids = h.ids[:0]
32	-	h.index = 0
33	-	}
34	-
35	-	func (h historyNavDisplay) active() bool {
36	-	return len(h.ids) > 0 && h.index >= 0 && h.index < len(h.ids)
37	-	}
38	-
39	-	func (n recentSessionNavigator) activeForDisplay() bool {
40	-	return len(n.ids) > 1 && n.index >= 0 && n.index < len(n.ids)
41	-	}
42	-
43	-	func recentSessionTrail(cur *session, state barState) []domain.SessionID {
44	-	if cur == nil {
45	-	return nil
46	-	}
47	-	ids := make([]domain.SessionID, 0, 1+len(state.mru))
48	-	ids = append(ids, cur.id)
49	-	for _, entry := range state.mru {
50	-	if entry.id != "" {
51	-	ids = append(ids, entry.id)
52	-	}
53	-	}
54	-	return ids
55	-	}
56	-
57	-	func (n *recentSessionNavigator) reset(ids []domain.SessionID) {
58	-	n.ids = append(n.ids[:0], ids...)
59	-	n.index = 0
60	-	}
61	-
62	-	func (d Daemon) navigateRecentSession(sess session, ac *attachedClient, delta int) {
63	-	if d == nil \|\| sess == nil \|\| ac == nil \|\| delta == 0 {
64	-	return
65	-	}
66	-	trail := recentSessionTrail(sess, d.barStateFor(sess, ""))
67	-	if ac.recentNav.index == 0 && !sameSessionTrail(ac.recentNav.ids, trail) {
68	-	ac.recentNav.reset(trail)
69	-	}
70	-	if !d.pruneRecentNav(&ac.recentNav) \|\| ac.recentNav.ids[ac.recentNav.index] != sess.id {
71	-	ac.recentNav.reset(trail)
72	-	}
73	-
74	-	next := ac.recentNav.index + delta
75	-	if next < 0 \|\| next >= len(ac.recentNav.ids) {
76	-	d.paint(sess, ac, true)
77	-	return
78	-	}
79	-	targetID := ac.recentNav.ids[next]
80	-	targetSess := d.sessionByID(targetID)
81	-	if targetSess == nil {
82	-	d.clearHistoryNav(ac)
83	-	d.paint(sess, ac, true)
84	-	return
85	-	}
86	-	d.switchToTarget(sess, ac, picker.Target{Session: targetID, TabIndex: -1})
87	-	if ac.currentSession() == targetSess {
88	-	ac.recentNav.index = next
89	-	d.showHistoryNav(ac)
90	-	d.paint(targetSess, ac, true)
91	-	}
92	-	}
93	-
94	-	func (d Daemon) showHistoryNav(ac attachedClient) {
95	-	if d == nil \|\| ac == nil \|\| !ac.recentNav.activeForDisplay() {
96	-	return
97	-	}
98	-	ac.historyNavMu.Lock()
99	-	ac.historyNav.set(ac.recentNav.ids, ac.recentNav.index, ac.historyNav.gen+1)
100	-	gen := ac.historyNav.gen
101	-	ac.historyNavTimer.stop()
102	-	ac.historyNavTimer.retain(d.clock, historyNavDisplayTimeout, func(ports.Timer) {
103	-	ac.historyNavMu.Lock()
104	-	if ac.historyNav.gen != gen {
105	-	ac.historyNavMu.Unlock()
106	-	return
107	-	}
108	-	ac.historyNav.clear()
109	-	ac.historyNavMu.Unlock()
110	-	if sess := ac.currentSession(); sess != nil {
111	-	sess.mu.Lock()
112	-	stillCurrent := sess.client == ac
113	-	sess.mu.Unlock()
114	-	if stillCurrent {
115	-	d.paint(sess, ac, true)
116	-	}
117	-	}
118	-	})
119	-	ac.historyNavMu.Unlock()
120	-	}
121	-
122	-	func (d Daemon) clearHistoryNav(ac attachedClient) {
123	-	if ac == nil {
124	-	return
125	-	}
126	-	ac.clearHistoryNav()
127	-	}
128	-
129	-	func (d Daemon) pruneRecentNav(n recentSessionNavigator) bool {
130	-	if n == nil \|\| len(n.ids) == 0 \|\| n.index < 0 \|\| n.index >= len(n.ids) {
131	-	return false
132	-	}
133	-	current := n.ids[n.index]
134	-	kept := n.ids[:0]
135	-	nextIndex := -1
136	-	for _, id := range n.ids {
137	-	if d.sessionByID(id) == nil {
138	-	continue
139	-	}
140	-	if id == current {
141	-	nextIndex = len(kept)
142	-	}
143	-	kept = append(kept, id)
144	-	}
145	-	n.ids = kept
146	-	if nextIndex == -1 {
147	-	return false
148	-	}
149	-	n.index = nextIndex
150	-	return true
151	-	}
152	-
153	-	func sameSessionTrail(a, b []domain.SessionID) bool {
154	-	if len(a) != len(b) {
155	-	return false
156	-	}
157	-	for i := range a {
158	-	if a[i] != b[i] {
159	-	return false
160	-	}
161	-	}
162	-	return true
163	-	}

@@ -1,163 +0,0 @@
1	-	package daemon
2	-
3	-	import (
4	-	"time"
5	-
6	-	"github.com/bnema/vev/internal/domain"
7	-	"github.com/bnema/vev/internal/ports"
8	-	"github.com/bnema/vev/internal/usecase/picker"
9	-	)
10	-
11	-	const historyNavDisplayTimeout = 1500 * time.Millisecond
12	-
13	-	type recentSessionNavigator struct {
14	-	ids []domain.SessionID
15	-	index int
16	-	}
17	-
18	-	type historyNavDisplay struct {
19	-	ids []domain.SessionID
20	-	index int
21	-	gen uint64
22	-	}
23	-
24	-	func (h *historyNavDisplay) set(ids []domain.SessionID, index int, gen uint64) {
25	-	h.ids = append(h.ids[:0], ids...)
26	-	h.index = index
27	-	h.gen = gen
28	-	}
29	-
30	-	func (h *historyNavDisplay) clear() {
31	-	h.ids = h.ids[:0]
32	-	h.index = 0
33	-	}
34	-
35	-	func (h historyNavDisplay) active() bool {
36	-	return len(h.ids) > 0 && h.index >= 0 && h.index < len(h.ids)
37	-	}
38	-
39	-	func (n recentSessionNavigator) activeForDisplay() bool {
40	-	return len(n.ids) > 1 && n.index >= 0 && n.index < len(n.ids)
41	-	}
42	-
43	-	func recentSessionTrail(cur *session, state barState) []domain.SessionID {
44	-	if cur == nil {
45	-	return nil
46	-	}
47	-	ids := make([]domain.SessionID, 0, 1+len(state.mru))
48	-	ids = append(ids, cur.id)
49	-	for _, entry := range state.mru {
50	-	if entry.id != "" {
51	-	ids = append(ids, entry.id)
52	-	}
53	-	}
54	-	return ids
55	-	}
56	-
57	-	func (n *recentSessionNavigator) reset(ids []domain.SessionID) {
58	-	n.ids = append(n.ids[:0], ids...)
59	-	n.index = 0
60	-	}
61	-
62	-	func (d Daemon) navigateRecentSession(sess session, ac *attachedClient, delta int) {
63	-	if d == nil \|\| sess == nil \|\| ac == nil \|\| delta == 0 {
64	-	return
65	-	}
66	-	trail := recentSessionTrail(sess, d.barStateFor(sess, ""))
67	-	if ac.recentNav.index == 0 && !sameSessionTrail(ac.recentNav.ids, trail) {
68	-	ac.recentNav.reset(trail)
69	-	}
70	-	if !d.pruneRecentNav(&ac.recentNav) \|\| ac.recentNav.ids[ac.recentNav.index] != sess.id {
71	-	ac.recentNav.reset(trail)
72	-	}
73	-
74	-	next := ac.recentNav.index + delta
75	-	if next < 0 \|\| next >= len(ac.recentNav.ids) {
76	-	d.paint(sess, ac, true)
77	-	return
78	-	}
79	-	targetID := ac.recentNav.ids[next]
80	-	targetSess := d.sessionByID(targetID)
81	-	if targetSess == nil {
82	-	d.clearHistoryNav(ac)
83	-	d.paint(sess, ac, true)
84	-	return
85	-	}
86	-	d.switchToTarget(sess, ac, picker.Target{Session: targetID, TabIndex: -1})
87	-	if ac.currentSession() == targetSess {
88	-	ac.recentNav.index = next
89	-	d.showHistoryNav(ac)
90	-	d.paint(targetSess, ac, true)
91	-	}
92	-	}
93	-
94	-	func (d Daemon) showHistoryNav(ac attachedClient) {
95	-	if d == nil \|\| ac == nil \|\| !ac.recentNav.activeForDisplay() {
96	-	return
97	-	}
98	-	ac.historyNavMu.Lock()
99	-	ac.historyNav.set(ac.recentNav.ids, ac.recentNav.index, ac.historyNav.gen+1)
100	-	gen := ac.historyNav.gen
101	-	ac.historyNavTimer.stop()
102	-	ac.historyNavTimer.retain(d.clock, historyNavDisplayTimeout, func(ports.Timer) {
103	-	ac.historyNavMu.Lock()
104	-	if ac.historyNav.gen != gen {
105	-	ac.historyNavMu.Unlock()
106	-	return
107	-	}
108	-	ac.historyNav.clear()
109	-	ac.historyNavMu.Unlock()
110	-	if sess := ac.currentSession(); sess != nil {
111	-	sess.mu.Lock()
112	-	stillCurrent := sess.client == ac
113	-	sess.mu.Unlock()
114	-	if stillCurrent {
115	-	d.paint(sess, ac, true)
116	-	}
117	-	}
118	-	})
119	-	ac.historyNavMu.Unlock()
120	-	}
121	-
122	-	func (d Daemon) clearHistoryNav(ac attachedClient) {
123	-	if ac == nil {
124	-	return
125	-	}
126	-	ac.clearHistoryNav()
127	-	}
128	-
129	-	func (d Daemon) pruneRecentNav(n recentSessionNavigator) bool {
130	-	if n == nil \|\| len(n.ids) == 0 \|\| n.index < 0 \|\| n.index >= len(n.ids) {
131	-	return false
132	-	}
133	-	current := n.ids[n.index]
134	-	kept := n.ids[:0]
135	-	nextIndex := -1
136	-	for _, id := range n.ids {
137	-	if d.sessionByID(id) == nil {
138	-	continue
139	-	}
140	-	if id == current {
141	-	nextIndex = len(kept)
142	-	}
143	-	kept = append(kept, id)
144	-	}
145	-	n.ids = kept
146	-	if nextIndex == -1 {
147	-	return false
148	-	}
149	-	n.index = nextIndex
150	-	return true
151	-	}
152	-
153	-	func sameSessionTrail(a, b []domain.SessionID) bool {
154	-	if len(a) != len(b) {
155	-	return false
156	-	}
157	-	for i := range a {
158	-	if a[i] != b[i] {
159	-	return false
160	-	}
161	-	}
162	-	return true
163	-	}

M internal/usecase/daemon/render_test.go +0 -65


@@ -1348,71 +1348,6 @@ func cursorCSI(row, col int) string {
1348	1348		return "\x1b[" + strconv.Itoa(row) + ";" + strconv.Itoa(col) + "H"
1349	1349		}
1350	1350
1351		-	func TestHistoryNavBottomBar(t *testing.T) {
1352		-	styles := newThemeStyles(themeui.Theme{})
1353		-
1354		-	t.Run("frozen order active styling and right text", func(t *testing.T) {
1355		-	row := make([]renderer.Cell, 40)
1356		-	state := barState{
1357		-	bottomRight: "script",
1358		-	history: []historyNavSession{
1359		-	{id: "work", name: "work"},
1360		-	{id: "api", name: "api", active: true},
1361		-	{id: "docs", name: "docs", ephemeral: true},
1362		-	},
1363		-	}
1364		-
1365		-	drawStatusBarState(row, state, styles)
1366		-
1367		-	got := cellsString(row)
1368		-	require.Contains(t, got, " work api docs* ")
1369		-	require.Contains(t, got, " script")
1370		-	apiCol := strings.Index(got, "api")
1371		-	require.NotEqual(t, -1, apiCol)
1372		-	require.True(t, row[apiCol].Style.Equal(styles.accent))
1373		-	workCol := strings.Index(got, "work")
1374		-	require.NotEqual(t, -1, workCol)
1375		-	require.True(t, row[workCol].Style.Equal(styles.statusBar))
1376		-	})
1377		-
1378		-	t.Run("empty history falls back to normal mru", func(t *testing.T) {
1379		-	row := make([]renderer.Cell, 30)
1380		-	state := barState{
1381		-	status: statusSnapshot{session: "work"},
1382		-	mru: []mruSession{{name: "api"}, {name: "docs"}},
1383		-	}
1384		-
1385		-	drawStatusBarState(row, state, styles)
1386		-
1387		-	got := cellsString(row)
1388		-	require.Contains(t, got, " work api docs ")
1389		-	workCol := strings.Index(got, "work")
1390		-	require.NotEqual(t, -1, workCol)
1391		-	require.True(t, row[workCol].Style.Equal(styles.accent))
1392		-	})
1393		-
1394		-	t.Run("narrow fitting keeps active visible in contiguous window", func(t *testing.T) {
1395		-	row := make([]renderer.Cell, 13)
1396		-	state := barState{history: []historyNavSession{
1397		-	{name: "work"},
1398		-	{name: "api"},
1399		-	{name: "docs", active: true},
1400		-	{name: "infra"},
1401		-	{name: "ops"},
1402		-	}}
1403		-
1404		-	drawStatusBarState(row, state, styles)
1405		-
1406		-	got := cellsString(row)
1407		-	require.Contains(t, got, "docs")
1408		-	require.NotContains(t, got, "work")
1409		-	require.NotContains(t, got, "ops")
1410		-	docsCol := strings.Index(got, "docs")
1411		-	require.NotEqual(t, -1, docsCol)
1412		-	require.True(t, row[docsCol].Style.Equal(styles.accent))
1413		-	})
1414		-	}
1415		-
1416	1351		func TestComposeCopyClientFrameOverlaysBaseAtTarget(t *testing.T) {
1417	1352		base := renderer.NewFrame(20, 8)
1418	1353		for y := range base.Height {


@@ -1348,71 +1348,6 @@ func cursorCSI(row, col int) string {
1348		return "\x1b[" + strconv.Itoa(row) + ";" + strconv.Itoa(col) + "H"	1348	return "\x1b[" + strconv.Itoa(row) + ";" + strconv.Itoa(col) + "H"
1349		}	1349	}
1350			1350
1351	-	func TestHistoryNavBottomBar(t *testing.T) {
1352	-	styles := newThemeStyles(themeui.Theme{})
1353	-
1354	-	t.Run("frozen order active styling and right text", func(t *testing.T) {
1355	-	row := make([]renderer.Cell, 40)
1356	-	state := barState{
1357	-	bottomRight: "script",
1358	-	history: []historyNavSession{
1359	-	{id: "work", name: "work"},
1360	-	{id: "api", name: "api", active: true},
1361	-	{id: "docs", name: "docs", ephemeral: true},
1362	-	},
1363	-	}
1364	-
1365	-	drawStatusBarState(row, state, styles)
1366	-
1367	-	got := cellsString(row)
1368	-	require.Contains(t, got, " work api docs* ")
1369	-	require.Contains(t, got, " script")
1370	-	apiCol := strings.Index(got, "api")
1371	-	require.NotEqual(t, -1, apiCol)
1372	-	require.True(t, row[apiCol].Style.Equal(styles.accent))
1373	-	workCol := strings.Index(got, "work")
1374	-	require.NotEqual(t, -1, workCol)
1375	-	require.True(t, row[workCol].Style.Equal(styles.statusBar))
1376	-	})
1377	-
1378	-	t.Run("empty history falls back to normal mru", func(t *testing.T) {
1379	-	row := make([]renderer.Cell, 30)
1380	-	state := barState{
1381	-	status: statusSnapshot{session: "work"},
1382	-	mru: []mruSession{{name: "api"}, {name: "docs"}},
1383	-	}
1384	-
1385	-	drawStatusBarState(row, state, styles)
1386	-
1387	-	got := cellsString(row)
1388	-	require.Contains(t, got, " work api docs ")
1389	-	workCol := strings.Index(got, "work")
1390	-	require.NotEqual(t, -1, workCol)
1391	-	require.True(t, row[workCol].Style.Equal(styles.accent))
1392	-	})
1393	-
1394	-	t.Run("narrow fitting keeps active visible in contiguous window", func(t *testing.T) {
1395	-	row := make([]renderer.Cell, 13)
1396	-	state := barState{history: []historyNavSession{
1397	-	{name: "work"},
1398	-	{name: "api"},
1399	-	{name: "docs", active: true},
1400	-	{name: "infra"},
1401	-	{name: "ops"},
1402	-	}}
1403	-
1404	-	drawStatusBarState(row, state, styles)
1405	-
1406	-	got := cellsString(row)
1407	-	require.Contains(t, got, "docs")
1408	-	require.NotContains(t, got, "work")
1409	-	require.NotContains(t, got, "ops")
1410	-	docsCol := strings.Index(got, "docs")
1411	-	require.NotEqual(t, -1, docsCol)
1412	-	require.True(t, row[docsCol].Style.Equal(styles.accent))
1413	-	})
1414	-	}
1415	-
1416		func TestComposeCopyClientFrameOverlaysBaseAtTarget(t *testing.T) {	1351	func TestComposeCopyClientFrameOverlaysBaseAtTarget(t *testing.T) {
1417		base := renderer.NewFrame(20, 8)	1352	base := renderer.NewFrame(20, 8)
1418		for y := range base.Height {	1353	for y := range base.Height {

M internal/usecase/daemon/session.go +2 -0


@@ -261,8 +261,10 @@ func (d Daemon) createSessionAndSwitch(from session, ac *attachedClient, name
261	261		newSess.mu.Lock()
262	262		newSess.client = ac
263	263		newSess.mu.Unlock()
	264	+
264	265		d.touchMRU(newSess)
265	266		ac.setSession(newSess)
	267	+	ac.recordPreviousSession(from)
266	268		d.log.Info("client attached", "session", newSess.name, "resume", ac.resumeCapable)
267	269		d.mu.Unlock()
268	270


@@ -261,8 +261,10 @@ func (d Daemon) createSessionAndSwitch(from session, ac *attachedClient, name
261	newSess.mu.Lock()	261		newSess.mu.Lock()
262	newSess.client = ac	262		newSess.client = ac
263	newSess.mu.Unlock()	263		newSess.mu.Unlock()
		264	+
264	d.touchMRU(newSess)	265		d.touchMRU(newSess)
265	ac.setSession(newSess)	266		ac.setSession(newSess)
		267	+	ac.recordPreviousSession(from)
266	d.log.Info("client attached", "session", newSess.name, "resume", ac.resumeCapable)	268		d.log.Info("client attached", "session", newSess.name, "resume", ac.resumeCapable)
267	d.mu.Unlock()	269		d.mu.Unlock()
268		270

A internal/usecase/daemon/session_back.go +26 -0

@@ -0,0 +1,26 @@
	1	+	package daemon
	2	+
	3	+	import "github.com/bnema/vev/internal/usecase/picker"
	4	+
	5	+	// backSession toggles this attachment between its current session and the
	6	+	// immediately preceding successfully activated session.
	7	+	func (d Daemon) backSession(current session, ac *attachedClient) {
	8	+	if d == nil \|\| current == nil \|\| ac == nil {
	9	+	return
	10	+	}
	11	+	target := ac.previousSession.Get()
	12	+	if target == nil \|\| target == current \|\| d.sessionByID(target.id) != target {
	13	+	d.paint(current, ac, true)
	14	+	return
	15	+	}
	16	+	d.switchToTarget(current, ac, picker.Target{Session: target.id, TabIndex: -1})
	17	+	}
	18	+
	19	+	// recordPreviousSession is called only after a cross-session hand-off has
	20	+	// committed. Keeping this after the commit makes failed/displaced switches
	21	+	// leave the toggle pair intact.
	22	+	func (ac attachedClient) recordPreviousSession(origin session) {
	23	+	if ac != nil && origin != nil {
	24	+	ac.previousSession.Set(origin)
	25	+	}
	26	+	}

@@ -0,0 +1,26 @@
	1	+	package daemon
	2	+
	3	+	import "github.com/bnema/vev/internal/usecase/picker"
	4	+
	5	+	// backSession toggles this attachment between its current session and the
	6	+	// immediately preceding successfully activated session.
	7	+	func (d Daemon) backSession(current session, ac *attachedClient) {
	8	+	if d == nil \|\| current == nil \|\| ac == nil {
	9	+	return
	10	+	}
	11	+	target := ac.previousSession.Get()
	12	+	if target == nil \|\| target == current \|\| d.sessionByID(target.id) != target {
	13	+	d.paint(current, ac, true)
	14	+	return
	15	+	}
	16	+	d.switchToTarget(current, ac, picker.Target{Session: target.id, TabIndex: -1})
	17	+	}
	18	+
	19	+	// recordPreviousSession is called only after a cross-session hand-off has
	20	+	// committed. Keeping this after the commit makes failed/displaced switches
	21	+	// leave the toggle pair intact.
	22	+	func (ac attachedClient) recordPreviousSession(origin session) {
	23	+	if ac != nil && origin != nil {
	24	+	ac.previousSession.Set(origin)
	25	+	}
	26	+	}

M internal/usecase/daemon/status.go +4 -139


@@ -19,10 +19,8 @@
19	19		//
20	20		// Locking: a pane's screen/scrollback and per-client renderer shadow are
21	21		// guarded by pane.mu/tab.mu as appropriate; the attached-client pointer by
22		-	// session.mu; the registry by Daemon.mu. History-navigation display state is
23		-	// guarded by attachedClient.historyNavMu. When more than one is held the order
24		-	// is always attachedClient.sendMu > attachedClient.historyNavMu > Daemon.mu >
25		-	// session.mu > tab.mu > pane.mu. The PTY reader only ever takes pane.mu, so it
	22	+	// session.mu; the registry by Daemon.mu. When more than one is held the order
	23	+	// is always attachedClient.sendMu > Daemon.mu > session.mu > tab.mu > pane.mu. The PTY reader only ever takes pane.mu, so it
26	24		// never blocks on a slow client.
27	25		package daemon
28	26

@@ -84,14 +82,7 @@ func drawStatusBarState(row []renderer.Cell, state barState, styles themeStyles)
84	82		clearStatusRow(row)
85	83		x := 0
86	84		rightText := composeBottomRightText(state.bottomRight, state.copyFeedback)
87		-	if len(state.history) > 0 {
88		-	drawHistoryNavSessions(row, &x, state.history, rightText, state.attentionFrame, styles)
89		-	drawRightPlainText(row, rightText, x, styles.statusBar)
90		-	return
91		-	}
92		-
93	85		writeStatusText(row, &x, " "+state.status.session+" ", styles.accent)
94		-
95	86		fittedMRU := fitMRU(state.mru, len(row), x, rightText)
96	87		for i, sess := range fittedMRU {
97	88		style := mruStyle(styles.statusBar, state.theme, i, len(fittedMRU))

@@ -100,16 +91,6 @@ func drawStatusBarState(row []renderer.Cell, state barState, styles themeStyles)
100	91		drawRightPlainText(row, rightText, x, styles.statusBar)
101	92		}
102	93
103		-	func drawHistoryNavSessions(row []renderer.Cell, x *int, entries []historyNavSession, rightText string, attentionFrame int, styles themeStyles) {
104		-	for _, sess := range fitHistoryNav(entries, len(row), *x, rightText) {
105		-	style := styles.statusBar
106		-	if sess.active {
107		-	style = styles.accent
108		-	}
109		-	drawStatusSessionEntry(row, x, sess.name, sess.ephemeral, sess.attention, style, attentionFrame)
110		-	}
111		-	}
112		-
113	94		func drawStatusSessionEntry(row []renderer.Cell, x *int, name string, ephemeral, attention bool, style renderer.Style, attentionFrame int) {
114	95		if ephemeral {
115	96		name += "*"

@@ -161,7 +142,6 @@ type barState struct {
161	142		bottomRight string
162	143		copyFeedback string
163	144		mru []mruSession
164		-	history []historyNavSession
165	145		attentionFrame int
166	146		// theme is the client's terminal theme, if reported. Its zero value
167	147		// (Theme{}, Known: false) is a valid "no theme" default that resolves to

@@ -178,14 +158,6 @@ type mruSession struct {
178	158		mruAt uint64
179	159		}
180	160
181		-	type historyNavSession struct {
182		-	id domain.SessionID
183		-	name string
184		-	ephemeral bool
185		-	attention bool
186		-	active bool
187		-	}
188		-
189	161		type statusSnapshot struct {
190	162		session string
191	163		tabs []statusTab

@@ -222,51 +194,8 @@ func tabDisplayName(tb *tab, index int) string {
222	194		return strconv.Itoa(index + 1)
223	195		}
224	196
225		-	func (d Daemon) barStateForClient(cur session, ac *attachedClient, copyFeedback string) barState {
226		-	state := d.barStateFor(cur, copyFeedback)
227		-	state.history = d.historyNavBarState(ac)
228		-	return state
229		-	}
230		-
231		-	func (d Daemon) historyNavBarState(ac attachedClient) []historyNavSession {
232		-	if d == nil \|\| ac == nil {
233		-	return nil
234		-	}
235		-	ac.historyNavMu.Lock()
236		-	if !ac.historyNav.active() {
237		-	ac.historyNavMu.Unlock()
238		-	return nil
239		-	}
240		-	ids := append([]domain.SessionID(nil), ac.historyNav.ids...)
241		-	activeIndex := ac.historyNav.index
242		-	ac.historyNavMu.Unlock()
243		-
244		-	d.mu.Lock()
245		-	out := make([]historyNavSession, 0, len(ids))
246		-	valid := true
247		-	for i, id := range ids {
248		-	sess := d.sessions[id]
249		-	if sess == nil {
250		-	valid = false
251		-	break
252		-	}
253		-	sess.mu.Lock()
254		-	entry := historyNavSession{id: sess.id, name: sess.name, ephemeral: sess.ephemeral, active: i == activeIndex}
255		-	for _, tb := range sess.tabs {
256		-	if tb.attention {
257		-	entry.attention = true
258		-	break
259		-	}
260		-	}
261		-	sess.mu.Unlock()
262		-	out = append(out, entry)
263		-	}
264		-	d.mu.Unlock()
265		-	if !valid {
266		-	d.clearHistoryNav(ac)
267		-	return nil
268		-	}
269		-	return out
	197	+	func (d Daemon) barStateForClient(cur session, _ *attachedClient, copyFeedback string) barState {
	198	+	return d.barStateFor(cur, copyFeedback)
270	199		}
271	200
272	201		func (d Daemon) barStateFor(cur session, copyFeedback string) barState {

@@ -319,70 +248,6 @@ func (d Daemon) barStateFor(cur session, copyFeedback string) barState {
319	248		return state
320	249		}
321	250
322		-	func fitHistoryNav(entries []historyNavSession, rowLen, leftUsed int, feedback string) []historyNavSession {
323		-	copyReserve := 1
324		-	if feedback != "" {
325		-	copyReserve = statusTextWidth(feedback) + 2
326		-	}
327		-	budget := rowLen - leftUsed - copyReserve
328		-	if budget <= 0 \|\| len(entries) == 0 {
329		-	return nil
330		-	}
331		-	cost := func(e historyNavSession) int {
332		-	name := e.name
333		-	if e.ephemeral {
334		-	name += "*"
335		-	}
336		-	n := 2 + statusTextWidth(name)
337		-	if e.attention {
338		-	n += 1 + renderer.RuneWidth(attentionGlyph)
339		-	}
340		-	return n
341		-	}
342		-	used := 0
343		-	for _, e := range entries {
344		-	used += cost(e)
345		-	}
346		-	if used <= budget {
347		-	return entries
348		-	}
349		-	active := 0
350		-	for i, e := range entries {
351		-	if e.active {
352		-	active = i
353		-	break
354		-	}
355		-	}
356		-	if cost(entries[active]) > budget {
357		-	return nil
358		-	}
359		-	start, end := active, active+1
360		-	used = cost(entries[active])
361		-	for {
362		-	expanded := false
363		-	if start > 0 {
364		-	c := cost(entries[start-1])
365		-	if used+c <= budget {
366		-	start--
367		-	used += c
368		-	expanded = true
369		-	}
370		-	}
371		-	if end < len(entries) {
372		-	c := cost(entries[end])
373		-	if used+c <= budget {
374		-	end++
375		-	used += c
376		-	expanded = true
377		-	}
378		-	}
379		-	if !expanded {
380		-	break
381		-	}
382		-	}
383		-	return entries[start:end]
384		-	}
385		-
386	251		// fitTabLabels returns, per tab, the text drawn between its surrounding
387	252		// spaces (attention glyph handled by the caller), guaranteeing all tabs fit.
388	253		func fitTabLabels(tabs []statusTab, rowLen int, rightText string) []string {


@@ -19,10 +19,8 @@
19		//	19		//
20		// Locking: a pane's screen/scrollback and per-client renderer shadow are	20		// Locking: a pane's screen/scrollback and per-client renderer shadow are
21		// guarded by pane.mu/tab.mu as appropriate; the attached-client pointer by	21		// guarded by pane.mu/tab.mu as appropriate; the attached-client pointer by
22	-	// session.mu; the registry by Daemon.mu. History-navigation display state is	22	+	// session.mu; the registry by Daemon.mu. When more than one is held the order
23	-	// guarded by attachedClient.historyNavMu. When more than one is held the order	23	+	// is always attachedClient.sendMu > Daemon.mu > session.mu > tab.mu > pane.mu. The PTY reader only ever takes pane.mu, so it
24	-	// is always attachedClient.sendMu > attachedClient.historyNavMu > Daemon.mu >
25	-	// session.mu > tab.mu > pane.mu. The PTY reader only ever takes pane.mu, so it
26		// never blocks on a slow client.	24		// never blocks on a slow client.
27		package daemon	25		package daemon
28			26

@@ -84,14 +82,7 @@ func drawStatusBarState(row []renderer.Cell, state barState, styles themeStyles)
84		clearStatusRow(row)	82		clearStatusRow(row)
85		x := 0	83		x := 0
86		rightText := composeBottomRightText(state.bottomRight, state.copyFeedback)	84		rightText := composeBottomRightText(state.bottomRight, state.copyFeedback)
87	-	if len(state.history) > 0 {
88	-	drawHistoryNavSessions(row, &x, state.history, rightText, state.attentionFrame, styles)
89	-	drawRightPlainText(row, rightText, x, styles.statusBar)
90	-	return
91	-	}
92	-
93		writeStatusText(row, &x, " "+state.status.session+" ", styles.accent)	85		writeStatusText(row, &x, " "+state.status.session+" ", styles.accent)
94	-
95		fittedMRU := fitMRU(state.mru, len(row), x, rightText)	86		fittedMRU := fitMRU(state.mru, len(row), x, rightText)
96		for i, sess := range fittedMRU {	87		for i, sess := range fittedMRU {
97		style := mruStyle(styles.statusBar, state.theme, i, len(fittedMRU))	88		style := mruStyle(styles.statusBar, state.theme, i, len(fittedMRU))

@@ -100,16 +91,6 @@ func drawStatusBarState(row []renderer.Cell, state barState, styles themeStyles)
100		drawRightPlainText(row, rightText, x, styles.statusBar)	91		drawRightPlainText(row, rightText, x, styles.statusBar)
101		}	92		}
102			93
103	-	func drawHistoryNavSessions(row []renderer.Cell, x *int, entries []historyNavSession, rightText string, attentionFrame int, styles themeStyles) {
104	-	for _, sess := range fitHistoryNav(entries, len(row), *x, rightText) {
105	-	style := styles.statusBar
106	-	if sess.active {
107	-	style = styles.accent
108	-	}
109	-	drawStatusSessionEntry(row, x, sess.name, sess.ephemeral, sess.attention, style, attentionFrame)
110	-	}
111	-	}
112	-
113		func drawStatusSessionEntry(row []renderer.Cell, x *int, name string, ephemeral, attention bool, style renderer.Style, attentionFrame int) {	94		func drawStatusSessionEntry(row []renderer.Cell, x *int, name string, ephemeral, attention bool, style renderer.Style, attentionFrame int) {
114		if ephemeral {	95		if ephemeral {
115		name += "*"	96		name += "*"

@@ -161,7 +142,6 @@ type barState struct {
161		bottomRight string	142		bottomRight string
162		copyFeedback string	143		copyFeedback string
163		mru []mruSession	144		mru []mruSession
164	-	history []historyNavSession
165		attentionFrame int	145		attentionFrame int
166		// theme is the client's terminal theme, if reported. Its zero value	146		// theme is the client's terminal theme, if reported. Its zero value
167		// (Theme{}, Known: false) is a valid "no theme" default that resolves to	147		// (Theme{}, Known: false) is a valid "no theme" default that resolves to

@@ -178,14 +158,6 @@ type mruSession struct {
178		mruAt uint64	158		mruAt uint64
179		}	159		}
180			160
181	-	type historyNavSession struct {
182	-	id domain.SessionID
183	-	name string
184	-	ephemeral bool
185	-	attention bool
186	-	active bool
187	-	}
188	-
189		type statusSnapshot struct {	161		type statusSnapshot struct {
190		session string	162		session string
191		tabs []statusTab	163		tabs []statusTab

@@ -222,51 +194,8 @@ func tabDisplayName(tb *tab, index int) string {
222		return strconv.Itoa(index + 1)	194		return strconv.Itoa(index + 1)
223		}	195		}
224			196
225	-	func (d Daemon) barStateForClient(cur session, ac *attachedClient, copyFeedback string) barState {	197	+	func (d Daemon) barStateForClient(cur session, _ *attachedClient, copyFeedback string) barState {
226	-	state := d.barStateFor(cur, copyFeedback)	198	+	return d.barStateFor(cur, copyFeedback)
227	-	state.history = d.historyNavBarState(ac)
228	-	return state
229	-	}
230	-
231	-	func (d Daemon) historyNavBarState(ac attachedClient) []historyNavSession {
232	-	if d == nil \|\| ac == nil {
233	-	return nil
234	-	}
235	-	ac.historyNavMu.Lock()
236	-	if !ac.historyNav.active() {
237	-	ac.historyNavMu.Unlock()
238	-	return nil
239	-	}
240	-	ids := append([]domain.SessionID(nil), ac.historyNav.ids...)
241	-	activeIndex := ac.historyNav.index
242	-	ac.historyNavMu.Unlock()
243	-
244	-	d.mu.Lock()
245	-	out := make([]historyNavSession, 0, len(ids))
246	-	valid := true
247	-	for i, id := range ids {
248	-	sess := d.sessions[id]
249	-	if sess == nil {
250	-	valid = false
251	-	break
252	-	}
253	-	sess.mu.Lock()
254	-	entry := historyNavSession{id: sess.id, name: sess.name, ephemeral: sess.ephemeral, active: i == activeIndex}
255	-	for _, tb := range sess.tabs {
256	-	if tb.attention {
257	-	entry.attention = true
258	-	break
259	-	}
260	-	}
261	-	sess.mu.Unlock()
262	-	out = append(out, entry)
263	-	}
264	-	d.mu.Unlock()
265	-	if !valid {
266	-	d.clearHistoryNav(ac)
267	-	return nil
268	-	}
269	-	return out
270		}	199		}
271			200
272		func (d Daemon) barStateFor(cur session, copyFeedback string) barState {	201		func (d Daemon) barStateFor(cur session, copyFeedback string) barState {

@@ -319,70 +248,6 @@ func (d Daemon) barStateFor(cur session, copyFeedback string) barState {
319		return state	248		return state
320		}	249		}
321			250
322	-	func fitHistoryNav(entries []historyNavSession, rowLen, leftUsed int, feedback string) []historyNavSession {
323	-	copyReserve := 1
324	-	if feedback != "" {
325	-	copyReserve = statusTextWidth(feedback) + 2
326	-	}
327	-	budget := rowLen - leftUsed - copyReserve
328	-	if budget <= 0 \|\| len(entries) == 0 {
329	-	return nil
330	-	}
331	-	cost := func(e historyNavSession) int {
332	-	name := e.name
333	-	if e.ephemeral {
334	-	name += "*"
335	-	}
336	-	n := 2 + statusTextWidth(name)
337	-	if e.attention {
338	-	n += 1 + renderer.RuneWidth(attentionGlyph)
339	-	}
340	-	return n
341	-	}
342	-	used := 0
343	-	for _, e := range entries {
344	-	used += cost(e)
345	-	}
346	-	if used <= budget {
347	-	return entries
348	-	}
349	-	active := 0
350	-	for i, e := range entries {
351	-	if e.active {
352	-	active = i
353	-	break
354	-	}
355	-	}
356	-	if cost(entries[active]) > budget {
357	-	return nil
358	-	}
359	-	start, end := active, active+1
360	-	used = cost(entries[active])
361	-	for {
362	-	expanded := false
363	-	if start > 0 {
364	-	c := cost(entries[start-1])
365	-	if used+c <= budget {
366	-	start--
367	-	used += c
368	-	expanded = true
369	-	}
370	-	}
371	-	if end < len(entries) {
372	-	c := cost(entries[end])
373	-	if used+c <= budget {
374	-	end++
375	-	used += c
376	-	expanded = true
377	-	}
378	-	}
379	-	if !expanded {
380	-	break
381	-	}
382	-	}
383	-	return entries[start:end]
384	-	}
385	-
386		// fitTabLabels returns, per tab, the text drawn between its surrounding	251		// fitTabLabels returns, per tab, the text drawn between its surrounding
387		// spaces (attention glyph handled by the caller), guaranteeing all tabs fit.	252		// spaces (attention glyph handled by the caller), guaranteeing all tabs fit.
388		func fitTabLabels(tabs []statusTab, rowLen int, rightText string) []string {	253		func fitTabLabels(tabs []statusTab, rowLen int, rightText string) []string {