Tighten PR refresh perf accounting

Co-authored-by: Orca <help@stably.ai>

src/main/github/pr-refresh-coordinator.test.ts

@@ -3,14 +3,19 @@ request timestamps, and follow-up scheduling against shared module state. */
 import { afterEach, beforeEach, describe, expect, it, vi } from 'vitest'
 import type { GitHubPRRefreshCandidate, PRInfo } from '../../shared/types'
 
-const { sendMock, getAllWebContentsMock, getPRForBranchOutcomeMock, getRateLimitMock } = vi.hoisted(
-  () => ({
-    sendMock: vi.fn(),
-    getAllWebContentsMock: vi.fn(),
-    getPRForBranchOutcomeMock: vi.fn(),
-    getRateLimitMock: vi.fn()
-  })
-)
+const {
+  sendMock,
+  getAllWebContentsMock,
+  getPRForBranchOutcomeMock,
+  getRateLimitMock,
+  noteRateLimitSpendMock
+} = vi.hoisted(() => ({
+  sendMock: vi.fn(),
+  getAllWebContentsMock: vi.fn(),
+  getPRForBranchOutcomeMock: vi.fn(),
+  getRateLimitMock: vi.fn(),
+  noteRateLimitSpendMock: vi.fn()
+}))
 
 vi.mock('electron', () => ({
   webContents: {
@@ -24,7 +29,7 @@ vi.mock('./client', () => ({
 
 vi.mock('./rate-limit', () => ({
   getRateLimit: getRateLimitMock,
-  noteRateLimitSpend: vi.fn(),
+  noteRateLimitSpend: noteRateLimitSpendMock,
   rateLimitGuard: vi.fn(() => ({ blocked: false }))
 }))
 
@@ -80,6 +85,7 @@ describe('pr-refresh-coordinator', () => {
     getAllWebContentsMock.mockReset()
     getPRForBranchOutcomeMock.mockReset()
     getRateLimitMock.mockReset()
+    noteRateLimitSpendMock.mockReset()
     getAllWebContentsMock.mockReturnValue([
       {
         id: 1,
@@ -770,6 +776,38 @@ describe('pr-refresh-coordinator', () => {
     )
   })
 
+  it('refreshes empty-branch candidates when a worktree HEAD hint exists', async () => {
+    const { refreshPRNow } = await import('./pr-refresh-coordinator')
+    getPRForBranchOutcomeMock.mockResolvedValueOnce({
+      kind: 'no-pr',
+      fetchedAt: Date.now()
+    })
+
+    await refreshPRNow(makeCandidate({ branch: '', worktreeHead: 'abcdef1' }))
+
+    expect(getPRForBranchOutcomeMock).toHaveBeenCalledWith('/repo', '', null, null, null, {
+      currentHeadOid: 'abcdef1'
+    })
+  })
+
+  it('accounts for the extra core probe on background PR refreshes', async () => {
+    const { reportVisiblePRRefreshCandidates } = await import('./pr-refresh-coordinator')
+    getPRForBranchOutcomeMock.mockResolvedValueOnce({
+      kind: 'no-pr',
+      fetchedAt: Date.now()
+    })
+
+    reportVisiblePRRefreshCandidates([makeCandidate({ worktreeHead: 'abcdef1' })], 1, 1)
+    await vi.runOnlyPendingTimersAsync()
+    await vi.advanceTimersByTimeAsync(10_000)
+
+    expect(noteRateLimitSpendMock.mock.calls.map(([bucket]) => bucket)).toEqual([
+      'core',
+      'core',
+      'graphql'
+    ])
+  })
+
   it('preserves coalesced aliases across visible follow-up refreshes', async () => {
     const { reportVisiblePRRefreshCandidates } = await import('./pr-refresh-coordinator')
     getPRForBranchOutcomeMock

src/main/github/pr-refresh-coordinator.ts

@@ -236,7 +236,12 @@ function validateCandidate(
   if (candidate.connectionId && candidate.connectionState === 'disconnected') {
     return 'disconnected'
   }
-  if (!candidate.branch && typeof candidate.linkedPRNumber !== 'number') {
+  if (
+    !candidate.branch &&
+    typeof candidate.linkedPRNumber !== 'number' &&
+    typeof candidate.fallbackPRNumber !== 'number' &&
+    !candidate.worktreeHead
+  ) {
     return 'fresh'
   }
   return null
@@ -463,10 +468,9 @@ function isMergeabilityPendingOutcome(outcome: PRRefreshOutcome): boolean {
 }
 
 function backgroundRefreshBuckets(): ('core' | 'graphql')[] {
-  // Why: branch refreshes prefer REST but can still fall back to `gh pr list`
-  // when local head-owner metadata is unavailable. Guard both buckets until the
-  // client exposes an exact per-lookup cost plan.
-  return ['core', 'graphql']
+  // Why: branch misses can now spend core on both branch and merge-commit REST
+  // probes; keep the coarse queue budget conservative until lookup cost is exact.
+  return ['core', 'core', 'graphql']
 }
 
 function noteBackgroundStart(): void {

src/renderer/src/store/slices/github.test.ts

@@ -1712,6 +1712,17 @@ describe('createGitHubSlice.fetchPRForBranch', () => {
           connectionId: 'ssh-1'
         }
       ],
+      worktreesByRepo: {
+        'repo-1': [
+          makePRRefreshWorktree({
+            id: 'wt-direct-refresh-head',
+            repoId: 'repo-1',
+            path: `${repoPath}/worktrees/direct-refresh`,
+            branch,
+            head: 'direct-head-oid'
+          })
+        ]
+      },
       prCache: {
         [`repo-1::${branch}`]: {
           data: pr,
@@ -1726,7 +1737,10 @@ describe('createGitHubSlice.fetchPRForBranch', () => {
     })
 
     await expect(
-      store.getState().fetchPRForBranch(repoPath, branch, { force: true })
+      store.getState().fetchPRForBranch(repoPath, branch, {
+        force: true,
+        worktreeId: 'wt-direct-refresh-head'
+      })
     ).resolves.toMatchObject({ number: 44 })
     expect(mockApi.gh.prForBranch).not.toHaveBeenCalled()
     expect(mockApi.gh.refreshPRNow).toHaveBeenCalledWith({
@@ -1735,6 +1749,7 @@ describe('createGitHubSlice.fetchPRForBranch', () => {
         repoPath,
         branch,
         cacheKey: `ssh:ssh-1::repo-1::${branch}`,
+        worktreeHead: 'direct-head-oid',
         connectionId: 'ssh-1'
       })
     })

src/renderer/src/store/slices/github.ts

@@ -2957,6 +2957,9 @@ export const createGitHubSlice: StateCreator<AppState, [], [], GitHubSlice> = (s
                 : ({ kind: 'no-pr', fetchedAt: Date.now() } as const)
             )
           : await (async () => {
+              const requestWorktree = options?.worktreeId
+                ? findWorktreeById(get(), options.worktreeId)
+                : null
               const candidate: GitHubPRRefreshCandidate = {
                 repoId: repoId ?? '',
                 repoPath,
@@ -2964,6 +2967,7 @@ export const createGitHubSlice: StateCreator<AppState, [], [], GitHubSlice> = (s
                 branch,
                 cacheKey,
                 worktreeId: options?.worktreeId,
+                worktreeHead: requestWorktree?.head ?? null,
                 linkedPRNumber,
                 fallbackPRNumber,
                 fallbackPRSource,