Write no false preview flag on a new or promoted tab (dark, layout-owner build only) (#30041)

Switch-on builds only; switch-off behaviour is unchanged.

Main stores a tab's preview flag only while it is true. A non-preview
editor open created its tab-bar entry with `isPreview: false`, and making
a preview permanent by an edit, by "keep open" or by pinning wrote the
same, so the window's next save changed that tab in main's model (the
save-divergence check's `tab <id> changed: isPreview` after a CLI file
open). New tabs now carry the flag only when true, and those writers drop
it, by the rule E2-4 gave activation, now in one place (tab-preview-flag).

Claude-Session: 10569c9a-a0a1-4fc9-8469-0edfb7aed125

src/renderer/src/store/slices/editor-tab-layout-owner.test.ts

@@ -10,6 +10,12 @@ import { LOCAL_EXECUTION_HOST_ID } from '../../../../shared/execution-host'
 import { applyLayoutCommand } from '../../../../shared/workspace-layout/workspace-layout-commands'
 import type { LayoutCommand } from '../../../../shared/workspace-layout/workspace-layout-command-types'
 import type { WorkspaceLayoutModel } from '../../../../shared/workspace-layout/workspace-layout-model'
+import { saveWorkspaceLayout } from '../../../../shared/workspace-layout/workspace-layout-save'
+import { asLoaded } from '../../../../shared/workspace-layout/workspace-layout-command.test-fixture'
+import { buildPersistedUnifiedTabSessionData } from '@/lib/workspace-session-unified-tabs'
+import { loadWorkspaceLayoutWithoutReport } from '../../../../shared/workspace-layout/workspace-layout-load'
+import { nameBasedLoadContext } from '../../../../shared/workspace-layout/workspace-layout-minted-ids'
+import type { WorkspaceSessionState } from '../../../../shared/workspace-session-state-types'
 
 const mocks = vi.hoisted(() => ({
   layoutOwnerIsMain: true,
@@ -123,6 +129,23 @@ function mainView() {
   }))
 }
 
+/** Main's tabs by id as loaded from a save, as main's save-divergence check reads them. */
+function loadedTabs(session: WorkspaceSessionState) {
+  const { layout } = loadWorkspaceLayoutWithoutReport(
+    LOCAL_EXECUTION_HOST_ID,
+    session,
+    nameBasedLoadContext()
+  )
+  return Object.fromEntries((layout.workspaces[WT]?.tabs ?? []).map((tab) => [tab.id, tab]))
+}
+
+/** Main's tabs, then the same after the window's tab-bar save lands on main's session. */
+function tabsBeforeAndAfterWindowSave() {
+  const mains = saveWorkspaceLayout(asLoaded(main))
+  const windows = { ...mains, ...buildPersistedUnifiedTabSessionData(store.getState()) }
+  return [loadedTabs(mains), loadedTabs(windows)]
+}
+
 function openFile(path: string, options?: { preview?: boolean; targetGroupId?: string }): string {
   return store
     .getState()
@@ -298,6 +321,42 @@ describe('editor tabs in a layout-owner build', () => {
     ).toBe(command!.type === 'openEditorTab' ? command.tabId : undefined)
   })
 
+  it('saves the tabs as main holds them, with no preview flag main does not store', () => {
+    openFile('/a.ts')
+    openFile('/b.ts', { targetGroupId: 'g2' })
+    applySent()
+    let [was, now] = tabsBeforeAndAfterWindowSave()
+    expect(now).toStrictEqual(was)
+
+    const c = openFile('/c.ts', { preview: true })
+    store.getState().markFileDirty(c, true)
+    const d = openFile('/d.ts', { preview: true, targetGroupId: 'g2' })
+    store.getState().makePreviewFilePermanent(d)
+    applySent()
+    ;[was, now] = tabsBeforeAndAfterWindowSave()
+    expect(now).toStrictEqual(was)
+  })
+
+  it('pins a preview tab without writing a preview flag', () => {
+    const a = openFile('/a.ts', { preview: true })
+    store.getState().pinTab(tabIn('g1', a))
+
+    const [tab] = store.getState().unifiedTabsByWorktree[WT]!
+    expect(tab?.isPinned).toBe(true)
+    expect(tab).not.toHaveProperty('isPreview')
+  })
+
+  it('keeps writing the preview flag as false with the switch off', () => {
+    mocks.layoutOwnerIsMain = false
+    const a = openFile('/a.ts')
+    const b = openFile('/b.ts', { preview: true })
+    store.getState().pinTab(tabIn('g1', b))
+
+    const tabs = store.getState().unifiedTabsByWorktree[WT]!
+    expect(tabs.find((tab) => tab.entityId === a)).toHaveProperty('isPreview', false)
+    expect(tabs.find((tab) => tab.entityId === b)).toHaveProperty('isPreview', false)
+  })
+
   it("sends an edit-mode file's record exactly as the window's session save keeps it", () => {
     const file = {
       id: 'f1',

src/renderer/src/store/slices/editor/actions/markdown-preview-actions.ts

@@ -14,6 +14,7 @@ import { buildEditorActiveResult } from '../tabs/editor-open-target-group'
 import { openWorkspaceEditorItem } from '../tabs/workspace-editor-item'
 import type { Tab } from '../../../../../../shared/tab-types'
 import { ORCA_LAYOUT_OWNER_IS_MAIN } from '../../../../../../shared/layout-owner-switch'
+import { withPreviewEnded } from '../../tabs/tab-preview-flag'
 import {
   previewEditorTabsOf,
   recordPromotedEditorTabsInLayoutOwner
@@ -188,7 +189,7 @@ export function createMarkdownPreviewActions(
               return tab
             }
             changed = true
-            return { ...tab, isPreview: false }
+            return withPreviewEnded(tab)
           })
         }
         return changed ? { openFiles, unifiedTabsByWorktree } : s

src/renderer/src/store/slices/editor/actions/open-file-mutations.ts

@@ -3,6 +3,7 @@ import type { EditorSlice } from '../types/editor-slice'
 import { isEditorTabContentType } from '../tabs/editor-tab-content-type'
 import type { Tab } from '../../../../../../shared/tab-types'
 import { ORCA_LAYOUT_OWNER_IS_MAIN } from '../../../../../../shared/layout-owner-switch'
+import { withPreviewEnded } from '../../tabs/tab-preview-flag'
 import {
   previewEditorTabsOf,
   recordPromotedEditorTabsInLayoutOwner
@@ -97,7 +98,7 @@ export function createOpenFileMutations(
                     worktreeId,
                     tabs.map((tab) =>
                       tab.entityId === fileId && isEditorTabContentType(tab.contentType)
-                        ? { ...tab, isPreview: false }
+                        ? withPreviewEnded(tab)
                         : tab
                     )
                   ])

src/renderer/src/store/slices/tabs/tab-preview-flag.ts

@@ -0,0 +1,22 @@
+// Switch point: main stores a tab's preview flag only while it is true, so a layout-owner build
+// writes no `isPreview: false` either; a save carrying one would change the tab in main's model.
+
+import type { Tab } from '../../../../../shared/tab-types'
+import { ORCA_LAYOUT_OWNER_IS_MAIN } from '../../../../../shared/layout-owner-switch'
+
+/** A new tab's preview flag. */
+export function createdTabPreviewFlag(isPreview: boolean | undefined): Pick<Tab, 'isPreview'> {
+  if (!ORCA_LAYOUT_OWNER_IS_MAIN) {
+    return { isPreview }
+  }
+  return isPreview ? { isPreview: true } : {}
+}
+
+/** The tab with its preview ended. */
+export function withPreviewEnded(tab: Tab): Tab {
+  if (!ORCA_LAYOUT_OWNER_IS_MAIN) {
+    return { ...tab, isPreview: false }
+  }
+  const { isPreview: _ended, ...rest } = tab
+  return rest
+}

src/renderer/src/store/slices/tabs/tabs-create-actions.ts

@@ -19,6 +19,7 @@ import {
 import { resolveUnifiedTabCreatePlacement } from './tabs-create-placement'
 import { emptySplitGroup, insertSplitGroup } from './tabs-group-actions'
 import { folderWorkspaceToWorktree } from '../../../../../shared/folder-workspace-worktree'
+import { createdTabPreviewFlag } from './tab-preview-flag'
 
 export function createTabsCreateActions(
   set: TabsSliceSet,
@@ -115,7 +116,7 @@ export function createTabsCreateActions(
           createdAt,
           // Why: creating an active tab is a focus event; Cmd+J recency reads lastFocusedAt.
           ...(recordsFocus ? { lastFocusedAt: createdAt } : {}),
-          isPreview: init?.isPreview,
+          ...createdTabPreviewFlag(init?.isPreview),
           isPinned: init?.isPinned
         }
 
@@ -195,7 +196,7 @@ export function createTabsCreateActions(
           createdAt,
           // Why: creating an active tab is a focus event; Cmd+J recency reads lastFocusedAt.
           ...(shouldActivate ? { lastFocusedAt: createdAt } : {}),
-          isPreview: init?.isPreview,
+          ...createdTabPreviewFlag(init?.isPreview),
           isPinned: init?.isPinned
         }
         const newGroup: TabGroup = {

src/renderer/src/store/slices/tabs/tabs-focus-actions.ts

@@ -8,17 +8,14 @@ import {
 import type { Tab } from '../../../../../shared/tab-types'
 import { ORCA_LAYOUT_OWNER_IS_MAIN } from '../../../../../shared/layout-owner-switch'
 import { recordPromotedEditorTabsInLayoutOwner } from '../editor/tabs/editor-tab-layout-owner'
+import { withPreviewEnded } from './tab-preview-flag'
 
-/** Activation ends a preview. Switch point: main stores no `isPreview: false`, so neither does this. */
+/** Activation ends a preview unless it preserves it. */
 function withPreviewOnActivation(tab: Tab, preservePreview: boolean): Tab {
   if (!ORCA_LAYOUT_OWNER_IS_MAIN) {
     return { ...tab, isPreview: preservePreview ? tab.isPreview : false }
   }
-  if (preservePreview) {
-    return tab
-  }
-  const { isPreview: _ended, ...rest } = tab
-  return rest
+  return preservePreview ? tab : withPreviewEnded(tab)
 }
 
 export function createTabsFocusActions(

src/renderer/src/store/slices/tabs/tabs-label-actions.ts

@@ -14,6 +14,7 @@ import {
 } from './tabs-host-mirroring'
 import { sendTabChangeToLayoutOwner } from '../../terminals/tab-change-through-layout-owner'
 import { recordTabOrderInLayoutOwner } from './tab-order-layout-owner'
+import { withPreviewEnded } from './tab-preview-flag'
 import { ORCA_LAYOUT_OWNER_IS_MAIN } from '../../../../../shared/layout-owner-switch'
 
 function oppositeViewMode(mode: 'terminal' | 'chat'): 'terminal' | 'chat' {
@@ -216,7 +217,7 @@ export function createTabsLabelActions(
         }
         const { tab, worktreeId } = found
         const tabs = (state.unifiedTabsByWorktree[worktreeId] ?? []).map((candidate) =>
-          candidate.id === tabId ? { ...candidate, isPinned: true, isPreview: false } : candidate
+          candidate.id === tabId ? withPreviewEnded({ ...candidate, isPinned: true }) : candidate
         )
         const groups = state.groupsByWorktree[worktreeId] ?? []
         const group = groups.find((candidate) => candidate.id === tab.groupId)