feat(picker): keep selection on the row replacing a killed session

commit: ae3ded7d0f3c5bc2d2ca44964733d5a749de78dd
author: brice · 2mo ago · 2026-07-29 14:32 UTC
parent: 4fcfd05
signature: GPG VerifiedCD88F9E564E0102646FB6077A1A07C7C7C3E349D · arch-gpg Verified for the committer email

5 files · +185 -43

M internal/usecase/daemon/move_picker.go +5 -0


@@ -175,6 +175,11 @@ func (d Daemon) refreshPickerOpts(ac attachedClient, opts pickerRefreshOptions
175	175		return
176	176		}
177	177		}
	178	+	// Navigate-only: move intents keep the selection-or-close logic above
	179	+	// authoritative, so a stale row index can never override it.
	180	+	if intent == pickerNavigate && opts.nearestRow >= 0 {
	181	+	model.SelectNearestRow(opts.nearestRow)
	182	+	}
178	183		rt.pickerMu.Lock()
179	184		updated := rt.picker != nil && rt.pickerIntent == intent && rt.pickerSource == source
180	185		if updated {


@@ -175,6 +175,11 @@ func (d Daemon) refreshPickerOpts(ac attachedClient, opts pickerRefreshOptions
175	return	175		return
176	}	176		}
177	}	177		}
		178	+	// Navigate-only: move intents keep the selection-or-close logic above
		179	+	// authoritative, so a stale row index can never override it.
		180	+	if intent == pickerNavigate && opts.nearestRow >= 0 {
		181	+	model.SelectNearestRow(opts.nearestRow)
		182	+	}
178	rt.pickerMu.Lock()	183		rt.pickerMu.Lock()
179	updated := rt.picker != nil && rt.pickerIntent == intent && rt.pickerSource == source	184		updated := rt.picker != nil && rt.pickerIntent == intent && rt.pickerSource == source
180	if updated {	185		if updated {

M internal/usecase/daemon/picker.go +4 -1


@@ -225,8 +225,11 @@ func (d Daemon) handlePickerInput(ac attachedClient, data []byte, effects ...*
225	225		var ok bool
226	226		var intent pickerIntent
227	227		var source moveSourceLocator
	228	+	// prevIdx is the row the victim occupied; -1 means "no post-delete hint".
	229	+	prevIdx := -1
228	230		if result.action == 'x' \|\| result.action == '\r' \|\| result.action == '\n' {
229	231		target, ok = rt.picker.Selected()
	232	+	prevIdx = rt.picker.SelectedIndex()
230	233		}
231	234		intent, source = rt.pickerIntent, rt.pickerSource
232	235		rt.pickerMu.Unlock()

@@ -261,7 +264,7 @@ func (d Daemon) handlePickerInput(ac attachedClient, data []byte, effects ...*
261	264		}
262	265		defer fresh.End()
263	266		}
264		-	d.refreshPicker(ac)
	267	+	d.refreshPickerOpts(ac, pickerRefreshOptions{nearestRow: prevIdx})
265	268		d.invalidateRender(sess, ac, true, "picker.go")
266	269		return
267	270		}

 	var ok bool
 	var intent pickerIntent
 	var source moveSourceLocator
+	// prevIdx is the row the victim occupied; -1 means "no post-delete hint".
+	prevIdx := -1
 	if result.action == 'x' || result.action == '\r' || result.action == '\n' {
 		target, ok = rt.picker.Selected()
+		prevIdx = rt.picker.SelectedIndex()
 	}
 	intent, source = rt.pickerIntent, rt.pickerSource
 	rt.pickerMu.Unlock()
 			}
 			defer fresh.End()
 		}
-		d.refreshPicker(ac)
+		d.refreshPickerOpts(ac, pickerRefreshOptions{nearestRow: prevIdx})
 		d.invalidateRender(sess, ac, true, "picker.go")
 		return
 	}

M internal/usecase/daemon/picker_test.go +81 -42


@@ -1616,51 +1616,90 @@ func TestPickerEnterOnStoppedSessionRestoreFailureSurfacesNoticeAndStaysPut(t *t
1616	1616		require.Same(t, from, ac.currentSession(), "a failed restore must leave the client on its origin session")
1617	1617		}
1618	1618
1619		-	func TestPickerNavigationRefreshAfterSuccessfulDeleteSelectsAttachedActiveStableTab(t *testing.T) {
1620		-	d, current, ac, _, currentReleases := newManualTabSession(t, 2)
1621		-	defer releaseAll(currentReleases)
1622		-	current.id, current.name, current.active = "current", "z-current", 1
1623		-	current.tabs[0].stableID, current.tabs[1].stableID = "current-first", "current-active"
1624		-	delete(d.sessions, domain.SessionID("manual"))
1625		-	d.sessions[current.id] = current
1626		-
1627		-	otherPTY, releaseOther := newBlockingPTY(t)
1628		-	defer releaseOther()
1629		-	otherTab := newTestTabWithContext(otherPTY, current.ctx, current.cancel)
1630		-	otherTab.stableID = "other-tab"
1631		-	other := &session{id: "other", name: "a-other", ephemeral: true, ctx: current.ctx, cancel: func() {}, tabs: []*tab{otherTab}}
1632		-	d.sessions[other.id] = other
1633		-
1634		-	targetPTY, releaseTarget := newBlockingPTY(t)
1635		-	defer releaseTarget()
1636		-	targetTab := newTestTabWithContext(targetPTY, current.ctx, current.cancel)
1637		-	targetTab.stableID = "target-tab"
1638		-	target := &session{id: "target", name: "m-target", ephemeral: true, ctx: current.ctx, cancel: func() {}, tabs: []*tab{targetTab}}
1639		-	d.sessions[target.id] = target
1640		-
1641		-	d.enterPicker(current, ac)
1642		-	d.handlePickerInput(ac, []byte("k"))
1643		-	d.handlePickerInput(ac, []byte("k"))
1644		-	ac.overlays.pickerMu.Lock()
1645		-	selected, ok := ac.overlays.picker.Selected()
1646		-	ac.overlays.pickerMu.Unlock()
1647		-	require.True(t, ok)
1648		-	require.Equal(t, target.id, selected.Session, "test must delete the selected non-attached session")
	1619	+	// TestPickerNavigationRefreshAfterDeleteSelectsReplacingRow pins the post-kill
	1620	+	// contract: the cursor stays on the row index the killed session occupied, so
	1621	+	// it lands on whatever session took its place — clamped to the new last
	1622	+	// selectable row when the bottom session was killed. Session names drive the
	1623	+	// picker's alphabetical tie-break (every session here shares mruAt 0), which is
	1624	+	// what puts the victim in the middle or at the end of the list.
	1625	+	func TestPickerNavigationRefreshAfterDeleteSelectsReplacingRow(t *testing.T) {
	1626	+	tests := []struct {
	1627	+	name string
	1628	+	currentName string
	1629	+	otherName string
	1630	+	targetName string
	1631	+	nav []byte // keys walked from the attached session's active tab onto the victim
	1632	+	wantSession domain.SessionID
	1633	+	wantTabID domain.TabStableID
	1634	+	wantTabIndex int
	1635	+	}{
	1636	+	{
	1637	+	// Rows: [a-other, other-tab, m-target, target-tab, z-current, current-first, current-active].
	1638	+	// Killing target-tab (row 3) promotes z-current's header to row 2, so
	1639	+	// row 3 becomes current-first — not the attached active tab.
	1640	+	name: "middle session killed selects the row taking its place",
	1641	+	currentName: "z-current", otherName: "a-other", targetName: "m-target",
	1642	+	nav: []byte("kk"),
	1643	+	wantSession: "current", wantTabID: "current-first", wantTabIndex: 0,
	1644	+	},
	1645	+	{
	1646	+	// Rows: [a-current, current-first, current-active, m-other, other-tab, z-target, target-tab].
	1647	+	// Killing the bottom row (6) clamps to the new last selectable row.
	1648	+	name: "last session killed selects the new last row",
	1649	+	currentName: "a-current", otherName: "m-other", targetName: "z-target",
	1650	+	nav: []byte("jj"),
	1651	+	wantSession: "other", wantTabID: "other-tab", wantTabIndex: 0,
	1652	+	},
	1653	+	}
	1654	+	for _, tt := range tests {
	1655	+	t.Run(tt.name, func(t *testing.T) {
	1656	+	d, current, ac, _, currentReleases := newManualTabSession(t, 2)
	1657	+	defer releaseAll(currentReleases)
	1658	+	current.id, current.name, current.active = "current", tt.currentName, 1
	1659	+	current.tabs[0].stableID, current.tabs[1].stableID = "current-first", "current-active"
	1660	+	delete(d.sessions, domain.SessionID("manual"))
	1661	+	d.sessions[current.id] = current
	1662	+
	1663	+	otherPTY, releaseOther := newBlockingPTY(t)
	1664	+	defer releaseOther()
	1665	+	otherTab := newTestTabWithContext(otherPTY, current.ctx, current.cancel)
	1666	+	otherTab.stableID = "other-tab"
	1667	+	other := &session{id: "other", name: tt.otherName, ephemeral: true, ctx: current.ctx, cancel: func() {}, tabs: []*tab{otherTab}}
	1668	+	d.sessions[other.id] = other
	1669	+
	1670	+	targetPTY, releaseTarget := newBlockingPTY(t)
	1671	+	defer releaseTarget()
	1672	+	targetTab := newTestTabWithContext(targetPTY, current.ctx, current.cancel)
	1673	+	targetTab.stableID = "target-tab"
	1674	+	target := &session{id: "target", name: tt.targetName, ephemeral: true, ctx: current.ctx, cancel: func() {}, tabs: []*tab{targetTab}}
	1675	+	d.sessions[target.id] = target
	1676	+
	1677	+	d.enterPicker(current, ac)
	1678	+	for _, key := range tt.nav {
	1679	+	d.handlePickerInput(ac, []byte{key})
	1680	+	}
	1681	+	ac.overlays.pickerMu.Lock()
	1682	+	selected, ok := ac.overlays.picker.Selected()
	1683	+	ac.overlays.pickerMu.Unlock()
	1684	+	require.True(t, ok)
	1685	+	require.Equal(t, target.id, selected.Session, "test must delete the selected non-attached session")
1649	1686
1650		-	d.handlePickerInput(ac, []byte("x"))
	1687	+	d.handlePickerInput(ac, []byte("x"))
1651	1688
1652		-	d.mu.Lock()
1653		-	_, targetStillLive := d.sessions[target.id]
1654		-	d.mu.Unlock()
1655		-	require.False(t, targetStillLive, "ordinary picker deletion must remove the selected session")
	1689	+	d.mu.Lock()
	1690	+	_, targetStillLive := d.sessions[target.id]
	1691	+	d.mu.Unlock()
	1692	+	require.False(t, targetStillLive, "ordinary picker deletion must remove the selected session")
1656	1693
1657		-	ac.overlays.pickerMu.Lock()
1658		-	selected, ok = ac.overlays.picker.Selected()
1659		-	ac.overlays.pickerMu.Unlock()
1660		-	require.True(t, ok)
1661		-	require.Equal(t, current.id, selected.Session)
1662		-	require.Equal(t, domain.TabStableID("current-active"), selected.TabID)
1663		-	require.Equal(t, 1, selected.TabIndex)
	1694	+	ac.overlays.pickerMu.Lock()
	1695	+	selected, ok = ac.overlays.picker.Selected()
	1696	+	ac.overlays.pickerMu.Unlock()
	1697	+	require.True(t, ok)
	1698	+	require.Equal(t, tt.wantSession, selected.Session)
	1699	+	require.Equal(t, tt.wantTabID, selected.TabID)
	1700	+	require.Equal(t, tt.wantTabIndex, selected.TabIndex)
	1701	+	})
	1702	+	}
1664	1703		}
1665	1704
1666	1705		func TestPickerRoleEffectDeleteRemovesSelectedSessionAndRefreshes(t *testing.T) {


@@ -1616,51 +1616,90 @@ func TestPickerEnterOnStoppedSessionRestoreFailureSurfacesNoticeAndStaysPut(t *t
1616		require.Same(t, from, ac.currentSession(), "a failed restore must leave the client on its origin session")	1616		require.Same(t, from, ac.currentSession(), "a failed restore must leave the client on its origin session")
1617		}	1617		}
1618			1618
1619	-	func TestPickerNavigationRefreshAfterSuccessfulDeleteSelectsAttachedActiveStableTab(t *testing.T) {	1619	+	// TestPickerNavigationRefreshAfterDeleteSelectsReplacingRow pins the post-kill
1620	-	d, current, ac, _, currentReleases := newManualTabSession(t, 2)	1620	+	// contract: the cursor stays on the row index the killed session occupied, so
1621	-	defer releaseAll(currentReleases)	1621	+	// it lands on whatever session took its place — clamped to the new last
1622	-	current.id, current.name, current.active = "current", "z-current", 1	1622	+	// selectable row when the bottom session was killed. Session names drive the
1623	-	current.tabs[0].stableID, current.tabs[1].stableID = "current-first", "current-active"	1623	+	// picker's alphabetical tie-break (every session here shares mruAt 0), which is
1624	-	delete(d.sessions, domain.SessionID("manual"))	1624	+	// what puts the victim in the middle or at the end of the list.
1625	-	d.sessions[current.id] = current	1625	+	func TestPickerNavigationRefreshAfterDeleteSelectsReplacingRow(t *testing.T) {
1626	-		1626	+	tests := []struct {
1627	-	otherPTY, releaseOther := newBlockingPTY(t)	1627	+	name string
1628	-	defer releaseOther()	1628	+	currentName string
1629	-	otherTab := newTestTabWithContext(otherPTY, current.ctx, current.cancel)	1629	+	otherName string
1630	-	otherTab.stableID = "other-tab"	1630	+	targetName string
1631	-	other := &session{id: "other", name: "a-other", ephemeral: true, ctx: current.ctx, cancel: func() {}, tabs: []*tab{otherTab}}	1631	+	nav []byte // keys walked from the attached session's active tab onto the victim
1632	-	d.sessions[other.id] = other	1632	+	wantSession domain.SessionID
1633	-		1633	+	wantTabID domain.TabStableID
1634	-	targetPTY, releaseTarget := newBlockingPTY(t)	1634	+	wantTabIndex int
1635	-	defer releaseTarget()	1635	+	}{
1636	-	targetTab := newTestTabWithContext(targetPTY, current.ctx, current.cancel)	1636	+	{
1637	-	targetTab.stableID = "target-tab"	1637	+	// Rows: [a-other, other-tab, m-target, target-tab, z-current, current-first, current-active].
1638	-	target := &session{id: "target", name: "m-target", ephemeral: true, ctx: current.ctx, cancel: func() {}, tabs: []*tab{targetTab}}	1638	+	// Killing target-tab (row 3) promotes z-current's header to row 2, so
1639	-	d.sessions[target.id] = target	1639	+	// row 3 becomes current-first — not the attached active tab.
1640	-		1640	+	name: "middle session killed selects the row taking its place",
1641	-	d.enterPicker(current, ac)	1641	+	currentName: "z-current", otherName: "a-other", targetName: "m-target",
1642	-	d.handlePickerInput(ac, []byte("k"))	1642	+	nav: []byte("kk"),
1643	-	d.handlePickerInput(ac, []byte("k"))	1643	+	wantSession: "current", wantTabID: "current-first", wantTabIndex: 0,
1644	-	ac.overlays.pickerMu.Lock()	1644	+	},
1645	-	selected, ok := ac.overlays.picker.Selected()	1645	+	{
1646	-	ac.overlays.pickerMu.Unlock()	1646	+	// Rows: [a-current, current-first, current-active, m-other, other-tab, z-target, target-tab].
1647	-	require.True(t, ok)	1647	+	// Killing the bottom row (6) clamps to the new last selectable row.
1648	-	require.Equal(t, target.id, selected.Session, "test must delete the selected non-attached session")	1648	+	name: "last session killed selects the new last row",
			1649	+	currentName: "a-current", otherName: "m-other", targetName: "z-target",
			1650	+	nav: []byte("jj"),
			1651	+	wantSession: "other", wantTabID: "other-tab", wantTabIndex: 0,
			1652	+	},
			1653	+	}
			1654	+	for _, tt := range tests {
			1655	+	t.Run(tt.name, func(t *testing.T) {
			1656	+	d, current, ac, _, currentReleases := newManualTabSession(t, 2)
			1657	+	defer releaseAll(currentReleases)
			1658	+	current.id, current.name, current.active = "current", tt.currentName, 1
			1659	+	current.tabs[0].stableID, current.tabs[1].stableID = "current-first", "current-active"
			1660	+	delete(d.sessions, domain.SessionID("manual"))
			1661	+	d.sessions[current.id] = current
			1662	+
			1663	+	otherPTY, releaseOther := newBlockingPTY(t)
			1664	+	defer releaseOther()
			1665	+	otherTab := newTestTabWithContext(otherPTY, current.ctx, current.cancel)
			1666	+	otherTab.stableID = "other-tab"
			1667	+	other := &session{id: "other", name: tt.otherName, ephemeral: true, ctx: current.ctx, cancel: func() {}, tabs: []*tab{otherTab}}
			1668	+	d.sessions[other.id] = other
			1669	+
			1670	+	targetPTY, releaseTarget := newBlockingPTY(t)
			1671	+	defer releaseTarget()
			1672	+	targetTab := newTestTabWithContext(targetPTY, current.ctx, current.cancel)
			1673	+	targetTab.stableID = "target-tab"
			1674	+	target := &session{id: "target", name: tt.targetName, ephemeral: true, ctx: current.ctx, cancel: func() {}, tabs: []*tab{targetTab}}
			1675	+	d.sessions[target.id] = target
			1676	+
			1677	+	d.enterPicker(current, ac)
			1678	+	for _, key := range tt.nav {
			1679	+	d.handlePickerInput(ac, []byte{key})
			1680	+	}
			1681	+	ac.overlays.pickerMu.Lock()
			1682	+	selected, ok := ac.overlays.picker.Selected()
			1683	+	ac.overlays.pickerMu.Unlock()
			1684	+	require.True(t, ok)
			1685	+	require.Equal(t, target.id, selected.Session, "test must delete the selected non-attached session")
1649			1686
1650	-	d.handlePickerInput(ac, []byte("x"))	1687	+	d.handlePickerInput(ac, []byte("x"))
1651			1688
1652	-	d.mu.Lock()	1689	+	d.mu.Lock()
1653	-	_, targetStillLive := d.sessions[target.id]	1690	+	_, targetStillLive := d.sessions[target.id]
1654	-	d.mu.Unlock()	1691	+	d.mu.Unlock()
1655	-	require.False(t, targetStillLive, "ordinary picker deletion must remove the selected session")	1692	+	require.False(t, targetStillLive, "ordinary picker deletion must remove the selected session")
1656			1693
1657	-	ac.overlays.pickerMu.Lock()	1694	+	ac.overlays.pickerMu.Lock()
1658	-	selected, ok = ac.overlays.picker.Selected()	1695	+	selected, ok = ac.overlays.picker.Selected()
1659	-	ac.overlays.pickerMu.Unlock()	1696	+	ac.overlays.pickerMu.Unlock()
1660	-	require.True(t, ok)	1697	+	require.True(t, ok)
1661	-	require.Equal(t, current.id, selected.Session)	1698	+	require.Equal(t, tt.wantSession, selected.Session)
1662	-	require.Equal(t, domain.TabStableID("current-active"), selected.TabID)	1699	+	require.Equal(t, tt.wantTabID, selected.TabID)
1663	-	require.Equal(t, 1, selected.TabIndex)	1700	+	require.Equal(t, tt.wantTabIndex, selected.TabIndex)
			1701	+	})
			1702	+	}
1664		}	1703		}
1665			1704
1666		func TestPickerRoleEffectDeleteRemovesSelectedSessionAndRefreshes(t *testing.T) {	1705		func TestPickerRoleEffectDeleteRemovesSelectedSessionAndRefreshes(t *testing.T) {

M internal/usecase/picker/model.go +31 -0


@@ -327,6 +327,37 @@ func (m *Model) Selected() (Target, bool) {
327	327		}, true
328	328		}
329	329
	330	+	// SelectedIndex reports the raw selected row index, -1 when nothing is
	331	+	// selected. Row indices are only meaningful against this exact model.
	332	+	func (m *Model) SelectedIndex() int {
	333	+	if m == nil {
	334	+	return -1
	335	+	}
	336	+	return m.selected
	337	+	}
	338	+
	339	+	// SelectNearestRow selects the first selectable row at or after idx, falling
	340	+	// back to the last selectable row before it. Callers use it to keep the
	341	+	// cursor on the row that takes a removed item's place.
	342	+	func (m *Model) SelectNearestRow(idx int) {
	343	+	if m == nil \|\| len(m.rows) == 0 {
	344	+	return
	345	+	}
	346	+	idx = clamp(idx, 0, len(m.rows)-1)
	347	+	for i := idx; i < len(m.rows); i++ {
	348	+	if m.rows[i].kind.selectable(m.mode) {
	349	+	m.selected = i
	350	+	return
	351	+	}
	352	+	}
	353	+	for i := idx - 1; i >= 0; i-- {
	354	+	if m.rows[i].kind.selectable(m.mode) {
	355	+	m.selected = i
	356	+	return
	357	+	}
	358	+	}
	359	+	}
	360	+
330	361		func (m Model) Clone() Model {
331	362		if m == nil {
332	363		return nil


@@ -327,6 +327,37 @@ func (m *Model) Selected() (Target, bool) {
327	}, true	327		}, true
328	}	328		}
329		329
		330	+	// SelectedIndex reports the raw selected row index, -1 when nothing is
		331	+	// selected. Row indices are only meaningful against this exact model.
		332	+	func (m *Model) SelectedIndex() int {
		333	+	if m == nil {
		334	+	return -1
		335	+	}
		336	+	return m.selected
		337	+	}
		338	+
		339	+	// SelectNearestRow selects the first selectable row at or after idx, falling
		340	+	// back to the last selectable row before it. Callers use it to keep the
		341	+	// cursor on the row that takes a removed item's place.
		342	+	func (m *Model) SelectNearestRow(idx int) {
		343	+	if m == nil \|\| len(m.rows) == 0 {
		344	+	return
		345	+	}
		346	+	idx = clamp(idx, 0, len(m.rows)-1)
		347	+	for i := idx; i < len(m.rows); i++ {
		348	+	if m.rows[i].kind.selectable(m.mode) {
		349	+	m.selected = i
		350	+	return
		351	+	}
		352	+	}
		353	+	for i := idx - 1; i >= 0; i-- {
		354	+	if m.rows[i].kind.selectable(m.mode) {
		355	+	m.selected = i
		356	+	return
		357	+	}
		358	+	}
		359	+	}
		360	+
330	func (m Model) Clone() Model {	361		func (m Model) Clone() Model {
331	if m == nil {	362		if m == nil {
332	return nil	363		return nil

M internal/usecase/picker/model_test.go +64 -0


@@ -406,6 +406,70 @@ func TestSelectedMapping(t *testing.T) {
406	406		require.Equal(t, Target{Session: "beta", TabID: "three", TabIndex: 1}, got)
407	407		}
408	408
	409	+	func TestSelectNearestRow(t *testing.T) {
	410	+	// Three single-tab sessions: rows are [hdrA, tabA, hdrB, tabB, hdrC, tabC].
	411	+	sessions := []SessionView{
	412	+	{ID: "a", Name: "a", Tabs: []TabEntry{{TabID: "ta", Name: "ta"}}},
	413	+	{ID: "b", Name: "b", Tabs: []TabEntry{{TabID: "tb", Name: "tb"}}},
	414	+	{ID: "c", Name: "c", Tabs: []TabEntry{{TabID: "tc", Name: "tc"}}},
	415	+	}
	416	+	tests := []struct {
	417	+	name string
	418	+	idx int
	419	+	want domain.SessionID
	420	+	}{
	421	+	{name: "exact selectable row", idx: 3, want: "b"},
	422	+	{name: "header row snaps to its tab", idx: 2, want: "b"},
	423	+	{name: "past end clamps to last selectable", idx: 40, want: "c"},
	424	+	{name: "negative clamps to first selectable", idx: -2, want: "a"},
	425	+	{name: "last row is a tab and stays put", idx: 5, want: "c"},
	426	+	}
	427	+	for _, tc := range tests {
	428	+	t.Run(tc.name, func(t *testing.T) {
	429	+	m := New(sessions, SelectionConfig{Mode: SelectNavigationTab})
	430	+	m.SelectNearestRow(tc.idx)
	431	+	target, ok := m.Selected()
	432	+	require.True(t, ok)
	433	+	require.Equal(t, tc.want, target.Session)
	434	+	})
	435	+	}
	436	+	}
	437	+
	438	+	func TestSelectNearestRowFallsBackBackwardAndToleratesEmptyModels(t *testing.T) {
	439	+	// Move-tab mode makes only session headers selectable, so the trailing tab
	440	+	// row has no selectable row at or after it.
	441	+	m := New([]SessionView{
	442	+	{ID: "a", Name: "a", Tabs: []TabEntry{{TabID: "ta", Name: "ta"}}},
	443	+	{ID: "b", Name: "b", Tabs: []TabEntry{{TabID: "tb", Name: "tb"}}},
	444	+	}, SelectionConfig{Mode: SelectMoveTabSession, Source: SourceFilter{Session: "zzz"}})
	445	+	require.Equal(t, 0, m.SelectedIndex(), "guard: the backward fallback below must move the selection off this starting row")
	446	+	m.SelectNearestRow(3)
	447	+	target, ok := m.Selected()
	448	+	require.True(t, ok)
	449	+	require.Equal(t, domain.SessionID("b"), target.Session)
	450	+	require.Equal(t, 2, m.SelectedIndex())
	451	+
	452	+	empty := New(nil, SelectionConfig{Mode: SelectNavigationTab})
	453	+	empty.SelectNearestRow(0)
	454	+	_, ok = empty.Selected()
	455	+	require.False(t, ok)
	456	+	require.Equal(t, -1, empty.SelectedIndex())
	457	+
	458	+	var nilModel *Model
	459	+	nilModel.SelectNearestRow(3)
	460	+	require.Equal(t, -1, nilModel.SelectedIndex())
	461	+	}
	462	+
	463	+	func TestSelectedIndexReportsRawSelectedRow(t *testing.T) {
	464	+	m := New([]SessionView{
	465	+	{ID: "alpha", Name: "alpha", Tabs: []TabEntry{{TabID: "one", Name: "one"}, {TabID: "two", Name: "two"}}},
	466	+	}, SelectionConfig{Mode: SelectNavigationTab, Current: SourceFilter{Session: "alpha", TabID: "two"}})
	467	+
	468	+	require.Equal(t, 2, m.SelectedIndex())
	469	+	m.Up()
	470	+	require.Equal(t, 1, m.SelectedIndex())
	471	+	}
	472	+
409	473		func TestStoppedSessionSelectableAndRendered(t *testing.T) {
410	474		m := New([]SessionView{{ID: "stopped:work", Name: "work", Tabs: []TabEntry{{Name: ""}}, Stopped: true}}, SelectionConfig{Mode: SelectNavigationTab})
411	475		got, ok := m.Selected()


@@ -406,6 +406,70 @@ func TestSelectedMapping(t *testing.T) {
406	require.Equal(t, Target{Session: "beta", TabID: "three", TabIndex: 1}, got)	406		require.Equal(t, Target{Session: "beta", TabID: "three", TabIndex: 1}, got)
407	}	407		}
408		408
		409	+	func TestSelectNearestRow(t *testing.T) {
		410	+	// Three single-tab sessions: rows are [hdrA, tabA, hdrB, tabB, hdrC, tabC].
		411	+	sessions := []SessionView{
		412	+	{ID: "a", Name: "a", Tabs: []TabEntry{{TabID: "ta", Name: "ta"}}},
		413	+	{ID: "b", Name: "b", Tabs: []TabEntry{{TabID: "tb", Name: "tb"}}},
		414	+	{ID: "c", Name: "c", Tabs: []TabEntry{{TabID: "tc", Name: "tc"}}},
		415	+	}
		416	+	tests := []struct {
		417	+	name string
		418	+	idx int
		419	+	want domain.SessionID
		420	+	}{
		421	+	{name: "exact selectable row", idx: 3, want: "b"},
		422	+	{name: "header row snaps to its tab", idx: 2, want: "b"},
		423	+	{name: "past end clamps to last selectable", idx: 40, want: "c"},
		424	+	{name: "negative clamps to first selectable", idx: -2, want: "a"},
		425	+	{name: "last row is a tab and stays put", idx: 5, want: "c"},
		426	+	}
		427	+	for _, tc := range tests {
		428	+	t.Run(tc.name, func(t *testing.T) {
		429	+	m := New(sessions, SelectionConfig{Mode: SelectNavigationTab})
		430	+	m.SelectNearestRow(tc.idx)
		431	+	target, ok := m.Selected()
		432	+	require.True(t, ok)
		433	+	require.Equal(t, tc.want, target.Session)
		434	+	})
		435	+	}
		436	+	}
		437	+
		438	+	func TestSelectNearestRowFallsBackBackwardAndToleratesEmptyModels(t *testing.T) {
		439	+	// Move-tab mode makes only session headers selectable, so the trailing tab
		440	+	// row has no selectable row at or after it.
		441	+	m := New([]SessionView{
		442	+	{ID: "a", Name: "a", Tabs: []TabEntry{{TabID: "ta", Name: "ta"}}},
		443	+	{ID: "b", Name: "b", Tabs: []TabEntry{{TabID: "tb", Name: "tb"}}},
		444	+	}, SelectionConfig{Mode: SelectMoveTabSession, Source: SourceFilter{Session: "zzz"}})
		445	+	require.Equal(t, 0, m.SelectedIndex(), "guard: the backward fallback below must move the selection off this starting row")
		446	+	m.SelectNearestRow(3)
		447	+	target, ok := m.Selected()
		448	+	require.True(t, ok)
		449	+	require.Equal(t, domain.SessionID("b"), target.Session)
		450	+	require.Equal(t, 2, m.SelectedIndex())
		451	+
		452	+	empty := New(nil, SelectionConfig{Mode: SelectNavigationTab})
		453	+	empty.SelectNearestRow(0)
		454	+	_, ok = empty.Selected()
		455	+	require.False(t, ok)
		456	+	require.Equal(t, -1, empty.SelectedIndex())
		457	+
		458	+	var nilModel *Model
		459	+	nilModel.SelectNearestRow(3)
		460	+	require.Equal(t, -1, nilModel.SelectedIndex())
		461	+	}
		462	+
		463	+	func TestSelectedIndexReportsRawSelectedRow(t *testing.T) {
		464	+	m := New([]SessionView{
		465	+	{ID: "alpha", Name: "alpha", Tabs: []TabEntry{{TabID: "one", Name: "one"}, {TabID: "two", Name: "two"}}},
		466	+	}, SelectionConfig{Mode: SelectNavigationTab, Current: SourceFilter{Session: "alpha", TabID: "two"}})
		467	+
		468	+	require.Equal(t, 2, m.SelectedIndex())
		469	+	m.Up()
		470	+	require.Equal(t, 1, m.SelectedIndex())
		471	+	}
		472	+
409	func TestStoppedSessionSelectableAndRendered(t *testing.T) {	473		func TestStoppedSessionSelectableAndRendered(t *testing.T) {
410	m := New([]SessionView{{ID: "stopped:work", Name: "work", Tabs: []TabEntry{{Name: ""}}, Stopped: true}}, SelectionConfig{Mode: SelectNavigationTab})	474		m := New([]SessionView{{ID: "stopped:work", Name: "work", Tabs: []TabEntry{{Name: ""}}, Stopped: true}}, SelectionConfig{Mode: SelectNavigationTab})
411	got, ok := m.Selected()	475		got, ok := m.Selected()