Cache mobile typechecks and overlap CI setup (#28192)

* ci: run mobile runtime test groups on separate runners

* ci: use a lightweight runner for the mobile result gate

* ci: distribute Bun tests across both mobile runners

* ci: reuse mobile compiler state without adding runner queues

* test: verify eviction of source variants in one cache bucket

* test: baseline existing serializer limits in the capacity capture

mobile/scripts/check-tests-typecheck-incremental-cache.test.ts

@@ -0,0 +1,47 @@
+import { existsSync, mkdtempSync, realpathSync, writeFileSync, unlinkSync } from 'node:fs'
+import { tmpdir } from 'node:os'
+import { join } from 'node:path'
+import { expect, it, vi } from 'vitest'
+import { removeTreeSync } from '../../src/shared/windows-transient-lock-removal'
+import { collectTypecheckPass, findTsNocheckFiles } from './check-tests-typecheck-ratchet.mjs'
+
+it('rechecks changed types, diagnostics and test membership with incremental state', () => {
+  const root = realpathSync(mkdtempSync(join(tmpdir(), 'orca-mobile-typecheck-')))
+  const cache = join(root, '.cache')
+  vi.stubEnv('ORCA_MOBILE_TYPECHECK_CACHE_DIR', cache)
+  try {
+    writeFileSync(
+      join(root, 'tsconfig.test.json'),
+      JSON.stringify({
+        compilerOptions: { strict: true, skipLibCheck: true, types: [], target: 'ES2022' },
+        include: ['*.ts']
+      })
+    )
+    writeFileSync(join(root, 'model.ts'), 'export interface Shape { value: number }')
+    const test = join(root, 'value.test.ts')
+    const source = "import type { Shape } from './model'; const shape: Shape = { value: 1 }"
+    writeFileSync(test, source)
+    const clean = collectTypecheckPass(root)
+    expect(clean).toEqual({ failing: [], programTestFiles: ['value.test.ts'] })
+    expect(existsSync(join(cache, 'tests.tsbuildinfo'))).toBe(true)
+    expect(collectTypecheckPass(root)).toEqual(clean)
+
+    writeFileSync(join(root, 'model.ts'), 'export interface Shape { value: string }')
+    const failed = collectTypecheckPass(root)
+    expect(failed.failing).toEqual(['value.test.ts'])
+    expect(collectTypecheckPass(root)).toEqual(failed)
+
+    writeFileSync(join(root, 'new.test.ts'), 'export const value: number = 1')
+    expect(collectTypecheckPass(root).programTestFiles).toEqual(['new.test.ts', 'value.test.ts'])
+    writeFileSync(test, `// @ts-nocheck\n${source}`)
+    const nocheck = collectTypecheckPass(root)
+    expect(nocheck.failing).toEqual([])
+    expect(findTsNocheckFiles(root, nocheck.programTestFiles)).toEqual(['value.test.ts'])
+
+    unlinkSync(test)
+    expect(collectTypecheckPass(root)).toEqual({ failing: [], programTestFiles: ['new.test.ts'] })
+  } finally {
+    vi.unstubAllEnvs()
+    removeTreeSync(root)
+  }
+}, 15_000)

mobile/scripts/check-tests-typecheck-ratchet.mjs

@@ -1,4 +1,4 @@
-import { spawnSync } from 'node:child_process'
+import { runProcessSync } from '@orca/process-host'
 import fs from 'node:fs'
 import { createRequire } from 'node:module'
 import path from 'node:path'
@@ -148,22 +148,26 @@ export function diffBaseline(current, baseline) {
 // script: on Windows the shim is tsc.CMD and an extensionless path gets .exe appended.
 function runTsc(root, args) {
   const entry = createRequire(import.meta.url).resolve('typescript/lib/tsc.js')
-  const result = spawnSync(process.execPath, [entry, ...args], {
+  return runProcessSync({
+    program: process.execPath,
+    args: [entry, ...args],
     cwd: root,
-    encoding: 'utf8',
-    shell: false,
-    maxBuffer: 64 * 1024 * 1024
+    timeoutMs: null,
+    maxOutputBytes: 64 * 1024 * 1024
   })
-  if (result.error) {
-    throw result.error
-  }
-  return result
 }
 
 // tsc exits non-zero on type errors, which is the expected state here, so only a crash is fatal.
 // One pass answers both questions: --listFiles names the program, the diagnostics name the failures.
 export function collectTypecheckPass(root = process.cwd()) {
-  const result = runTsc(root, ['--noEmit', '--listFiles', '-p', PROJECT])
+  const cache = process.env.ORCA_MOBILE_TYPECHECK_CACHE_DIR
+  const result = runTsc(root, [
+    '--noEmit',
+    '--listFiles',
+    '-p',
+    PROJECT,
+    ...(cache ? ['--incremental', '--tsBuildInfoFile', path.join(cache, 'tests.tsbuildinfo')] : [])
+  ])
   const output = `${result.stdout ?? ''}${result.stderr ?? ''}`
   return {
     failing: parseFailingFiles(output),