ci: restore five unit runners and prune source-only tests (#26437)

* ci: reduce unit runner demand and reuse the loaded preview frame

* test: remove source spelling probes without behavioral assertions

.github/workflows/pr.yml

@@ -432,8 +432,8 @@ jobs:
           PREFLIGHT_PHASE_SELECTED: ${{ needs.code_paths.outputs.typecheck == 'true' }}
           PREFLIGHT_PRIOR_SUCCESS: ${{ job.status == 'success' }}
           ORCA_UNIT_SELECTION_MODE: ${{ vars.ORCA_UNIT_SELECTION_MODE || 'shadow' }}
-          # Set the repository variable to '5' to roll back full PR shards.
-          ORCA_UNIT_FULL_SHARD_COUNT: ${{ vars.ORCA_UNIT_FULL_SHARD_COUNT || '10' }}
+          # Five shards use fewer runner minutes; the repository variable can still request ten.
+          ORCA_UNIT_FULL_SHARD_COUNT: ${{ vars.ORCA_UNIT_FULL_SHARD_COUNT || '5' }}
         run: |
           if [ "$PREFLIGHT_PHASE_SELECTED" != true ] || [ "$PREFLIGHT_PRIOR_SUCCESS" != true ]; then exit 0; fi
           node config/scripts/ci-unit-plan.mjs

config/scripts/ci-unit-selection.mjs

@@ -35,7 +35,7 @@ export function selectUnitFiles(files, changed, graphInput) {
 // the account's slots and made the unit matrix 68% of daily slot demand. Against the checked-in
 // baseline, five shards each carry 24.7 test-minutes over four workers plus ~2.6 minutes of fixed
 // setup, so ~8.8 minutes -- less than the 10.5-minute p95 queue the oversharding was causing.
-// Full PR workflows request ten; daily callers and selected drafts retain five.
+// Full PR workflows and daily callers use five; selected drafts may use fewer.
 export const FULL_SHARD_COUNT = 5
 
 export function planUnitSelection({

config/scripts/mobile-web-app-preview-arm-driver.mjs

@@ -186,7 +186,10 @@ export async function openPreviewArm(
     if (act) {
       // Recorded, never swallowed: a click that never landed and a click that produced no
       // navigation are the same empty counter, and only one of them is the product's doing.
-      await act({ page, frame: previewFrame(page) }).catch((error) => {
+      if (!artifactFrame || artifactFrame.isDetached()) {
+        throw new Error('The loaded preview frame is missing before its action')
+      }
+      await act({ page, frame: artifactFrame }).catch((error) => {
         actError = String(error).split('\n')[0]
       })
     }

config/scripts/pr-preflight-gates.test.mjs

@@ -32,7 +32,7 @@ it('shares one setup and runs the unchanged compiler after static checks finish'
     'node config/scripts/ci-unit-plan.mjs'
   ])
   expect(plan.env.ORCA_UNIT_SELECTION_MODE).toContain('vars.ORCA_UNIT_SELECTION_MODE')
-  expect(plan.env.ORCA_UNIT_FULL_SHARD_COUNT).toBe("${{ vars.ORCA_UNIT_FULL_SHARD_COUNT || '10' }}")
+  expect(plan.env.ORCA_UNIT_FULL_SHARD_COUNT).toBe("${{ vars.ORCA_UNIT_FULL_SHARD_COUNT || '5' }}")
   expect(steps.indexOf(plan)).toBeLessThan(steps.indexOf(compiler))
   expect(steps.indexOf(compiler)).toBeGreaterThan(
     steps.findIndex((step) => step.wait?.includes('localization-extraction'))

src/main/pi/prefill-extension-source.test.ts

@@ -1,14 +0,0 @@
-import { describe, expect, it } from 'vitest'
-import { getPiPrefillExtensionSource } from './prefill-extension-source'
-
-describe('getPiPrefillExtensionSource', () => {
-  it('accepts OMP session_start events without a reason field', () => {
-    const source = getPiPrefillExtensionSource('omp')
-    expect(source).toContain('process.env.ORCA_OMP_PREFILL')
-    expect(source).not.toContain("event.reason !== 'startup'")
-  })
-
-  it('keeps Pi startup reason filtering', () => {
-    expect(getPiPrefillExtensionSource('pi')).toContain("event.reason !== 'startup'")
-  })
-})

src/renderer/src/lazy-use-ref-ratchet.test.ts

@@ -1,130 +0,0 @@
-import { readFileSync, readdirSync } from 'node:fs'
-import path from 'node:path'
-import { describe, expect, it } from 'vitest'
-
-/**
- * `useRef(create())` evaluates its argument on EVERY render and discards every result after the
- * first, so any real work there is pure waste. The lazy form keeps the same value with none of the
- * churn:
- *
- *   const ref = useRef<T>(undefined!)
- *   ref.current ??= create()
- *
- * Use a `useState` lazy initializer instead when the seed can legitimately be null/undefined, or
- * an explicit `seededRef` guard when both are true.
- */
-const RENDERER_ROOT = import.meta.dirname
-
-function collectSourceFiles(dir: string, out: string[] = []): string[] {
-  for (const entry of readdirSync(dir, { withFileTypes: true })) {
-    const full = path.join(dir, entry.name)
-    if (entry.isDirectory()) {
-      if (entry.name === 'node_modules' || entry.name === 'dist') {
-        continue
-      }
-      collectSourceFiles(full, out)
-      continue
-    }
-    if (!/\.tsx?$/.test(entry.name) || /\.(test|spec)\.tsx?$/.test(entry.name)) {
-      continue
-    }
-    out.push(full)
-  }
-  return out
-}
-
-/** Reads the balanced argument text of the `useRef(...)` starting at `from`. */
-function readUseRefArgument(source: string, from: number): { arg: string; end: number } | null {
-  let i = from
-  while (source[i] === ' ') {
-    i++
-  }
-  if (source[i] === '<') {
-    let depth = 0
-    while (i < source.length) {
-      if (source[i] === '<') {
-        depth++
-      } else if (source[i] === '>') {
-        depth--
-        if (depth === 0) {
-          i++
-          break
-        }
-      }
-      i++
-    }
-  }
-  while (source[i] === ' ') {
-    i++
-  }
-  if (source[i] !== '(') {
-    return null
-  }
-  const argStart = i + 1
-  let depth = 0
-  while (i < source.length) {
-    if (source[i] === '(') {
-      depth++
-    } else if (source[i] === ')') {
-      depth--
-      if (depth === 0) {
-        return { arg: source.slice(argStart, i).trim(), end: i + 1 }
-      }
-    }
-    i++
-  }
-  return null
-}
-
-// Allowed because none of these is work that a render repeats for nothing:
-//  - an empty collection literal, which the repo keeps in the direct form
-//  - `undefined!`, the lazy-seed marker
-//  - a function literal, which is the ref's payload rather than its initialization
-//  - a primitive coercion of an already-computed value
-const ALLOWED_ARGUMENT = new RegExp(
-  [
-    '^new (Map|Set|WeakMap|WeakSet)(<[\\s\\S]*>)?\\(\\)$',
-    '^undefined!$',
-    '^(async )?\\([\\s\\S]*?\\)\\s*(:[^=]*)?=>[\\s\\S]*$',
-    '^(Boolean|Number|String)\\([\\s\\S]*\\)$',
-    '^[A-Za-z_$][\\w$.?\\[\\]\'"]*$'
-  ].join('|')
-)
-
-function findNonLazyUseRefs(file: string): string[] {
-  const source = readFileSync(file, 'utf8')
-  const findings: string[] = []
-  let index = 0
-  while ((index = source.indexOf('useRef', index)) !== -1) {
-    const start = index
-    index += 'useRef'.length
-    if (/[\w$.]/.test(source[start - 1] ?? '')) {
-      continue
-    }
-    const parsed = readUseRefArgument(source, index)
-    if (!parsed) {
-      continue
-    }
-    index = parsed.end
-    const arg = parsed.arg
-    if (arg === '' || ALLOWED_ARGUMENT.test(arg)) {
-      continue
-    }
-    // Only a call or constructor invocation actually burns work per render.
-    if (!/\(/.test(arg) && !/\bnew\b/.test(arg)) {
-      continue
-    }
-    const line = source.slice(0, start).split('\n').length
-    findings.push(
-      `${path.relative(RENDERER_ROOT, file)}:${line} useRef(${arg.replace(/\s+/g, ' ').slice(0, 90)})`
-    )
-  }
-  return findings
-}
-
-describe('renderer useRef initializers', () => {
-  it('never does work in the useRef argument', () => {
-    const findings = collectSourceFiles(RENDERER_ROOT).flatMap(findNonLazyUseRefs)
-    expect(findings).toEqual([])
-  })
-})