perf: reuse normalized task-page repository selection (#19454)

* perf: reuse normalized task-page repository selection

* test(task-page): cover ineligible persisted repo IDs in initial selection

---------

Co-authored-by: m4air <m4air@m4airs-MacBook-Air.local>
Co-authored-by: Neil <4138956+nwparker@users.noreply.github.com>

src/renderer/src/components/task-page-initial-selection-scaling.test.tsx

@@ -0,0 +1,88 @@
+import { describe, expect, it } from 'vitest'
+import { renderToString } from 'react-dom/server'
+import type { Repo } from '../../../shared/repo-types'
+import type { TaskPageStoreBindingsModel } from './use-task-page-store-bindings'
+import { useTaskPageRepoSelection } from './use-task-page-repo-selection'
+
+function resolveSelection(repos: Repo[], persisted: string[], preferred?: string) {
+  let selected: readonly string[] = []
+  function Probe() {
+    const model = {
+      repos,
+      settings: { defaultRepoSelection: persisted },
+      pageData: { preselectedRepoId: preferred },
+      linearStatus: {},
+      jiraStatus: {},
+      preflightStatus: null
+    } as unknown as TaskPageStoreBindingsModel
+    useTaskPageRepoSelection(model)
+    selected = [
+      ...(model as TaskPageStoreBindingsModel & { resolvedInitialSelection: ReadonlySet<string> })
+        .resolvedInitialSelection
+    ]
+    return null
+  }
+  renderToString(<Probe />)
+  return selected
+}
+
+describe('task page initial repo selection', () => {
+  it('normalizes persisted selections without a repository scan for every stored ID', () => {
+    let reads = 0
+    const repos: Repo[] = Array.from({ length: 1000 }, (_, index) => ({
+      get id() {
+        reads++
+        return `repo-${index}`
+      },
+      path: `/repos/${index}`,
+      displayName: `Repo ${index}`,
+      badgeColor: '',
+      addedAt: index,
+      kind: 'git'
+    }))
+    const persisted = Array.from({ length: 1000 }, (_, index) => `repo-${index}`)
+    expect(resolveSelection(repos, persisted)).toEqual(persisted)
+    expect(reads).toBeLessThan(40_000)
+  })
+
+  it('retains preferred selection, missing-ID fallback, and explicit empty defaults', () => {
+    const repos: Repo[] = ['a', 'b'].map((id) => ({
+      id,
+      path: `/repos/${id}`,
+      displayName: id,
+      badgeColor: '',
+      addedAt: 0,
+      kind: 'git'
+    }))
+    expect(resolveSelection(repos, ['b'], 'a')).toEqual(['a'])
+    expect(resolveSelection(repos, ['missing'])).toEqual(['a', 'b'])
+    expect(resolveSelection(repos, [])).toEqual(['a', 'b'])
+    expect(resolveSelection(repos, ['missing', 'b', 'b'])).toEqual(['b'])
+  })
+
+  it('ignores persisted IDs for ineligible repos, including folder workspaces', () => {
+    const repos: Repo[] = [
+      {
+        id: 'tracked',
+        path: '/repos/tracked',
+        displayName: 'tracked',
+        badgeColor: '',
+        addedAt: 0,
+        kind: 'git'
+      },
+      {
+        id: 'folder',
+        path: '/repos/folder',
+        displayName: 'folder',
+        badgeColor: '',
+        addedAt: 1,
+        kind: 'folder'
+      }
+    ]
+
+    // A folder workspace is never task-eligible, so a stored selection naming only one must fall
+    // through to the automatic default rather than rendering an empty picker.
+    expect(resolveSelection(repos, ['folder'])).toEqual(['tracked'])
+    expect(resolveSelection(repos, ['folder', 'tracked'])).toEqual(['tracked'])
+  })
+})

src/renderer/src/components/use-task-page-repo-selection.ts

@@ -51,11 +51,7 @@ export function useTaskPageRepoSelection(model: TaskPageStoreBindingsModel) {
     }
     const persisted = settings?.defaultRepoSelection
     if (Array.isArray(persisted)) {
-      const filtered = persisted.filter((id) => eligibleRepos.some((r) => r.id === id))
-      if (filtered.length > 0) {
-        return normalizeTaskRepoSelection(eligibleRepos, new Set(filtered))
-      }
-      // Why: empty after filtering (all persisted repos removed) falls through to the automatic default so the page never renders an empty selection.
+      return normalizeTaskRepoSelection(eligibleRepos, new Set(persisted))
     }
     return getDefaultTaskRepoSelection(eligibleRepos)
   }, [eligibleRepos, pageData.preselectedRepoId, settings?.defaultRepoSelection])