refactor: lazy initialize caches (#156)

.changeset/neat-rings-joke.md

@@ -0,0 +1,5 @@
+---
+"synckit": patch
+---
+
+refactor: lazy initialize caches

benchmarks/benchmark.cjs

@@ -81,8 +81,8 @@ class Benchmark {
     return a === b
       ? 'same'
       : a > b
-      ? (a / b).toFixed(2) + 'x slower'
-      : (b / a).toFixed(2) + 'x faster'
+        ? (a / b).toFixed(2) + 'x slower'
+        : (b / a).toFixed(2) + 'x faster'
   }
 }
 

benchmarks/benchmark.js

@@ -86,8 +86,8 @@ class Benchmark {
     return a === b
       ? 'same'
       : a > b
-      ? (a / b).toFixed(2) + 'x slower'
-      : (b / a).toFixed(2) + 'x faster'
+        ? (a / b).toFixed(2) + 'x slower'
+        : (b / a).toFixed(2) + 'x faster'
   }
 }
 

package.json

@@ -56,12 +56,12 @@
     "tslib": "^2.6.2"
   },
   "devDependencies": {
-    "@1stg/lib-config": "^12.0.0",
+    "@1stg/lib-config": "^13.0.0",
     "@changesets/changelog-github": "^0.5.0",
     "@changesets/cli": "^2.27.1",
     "@swc-node/register": "^1.6.8",
-    "@types/jest": "^29.5.10",
-    "@types/node": "^20.10.1",
+    "@types/jest": "^29.5.11",
+    "@types/node": "^20.10.6",
     "clean-pkg-json": "^1.2.0",
     "cross-env": "^7.0.3",
     "deasync": "^0.1.29",
@@ -73,14 +73,13 @@
     "sync-threads": "^1.0.1",
     "ts-expect": "^1.3.0",
     "ts-jest": "^29.1.1",
-    "ts-node": "^10.9.1",
-    "tsx": "^4.6.1",
-    "type-coverage": "^2.27.0",
-    "typescript": "^5.3.2",
+    "ts-node": "^10.9.2",
+    "tsx": "^4.7.0",
+    "type-coverage": "^2.27.1",
+    "typescript": "^5.3.3",
     "yarn-deduplicate": "^6.0.2"
   },
   "resolutions": {
-    "prettier": "^2.8.8",
     "synckit": "link:."
   },
   "commitlint": {

src/index.ts

@@ -46,11 +46,11 @@ export const TsRunner = {
 export type TsRunner = ValueOf<typeof TsRunner>
 
 const {
-  SYNCKIT_TIMEOUT,
+  NODE_OPTIONS,
   SYNCKIT_EXEC_ARGV,
-  SYNCKIT_TS_RUNNER,
   SYNCKIT_GLOBAL_SHIMS,
-  NODE_OPTIONS,
+  SYNCKIT_TIMEOUT,
+  SYNCKIT_TS_RUNNER,
 } = process.env
 
 export const DEFAULT_TIMEOUT = SYNCKIT_TIMEOUT ? +SYNCKIT_TIMEOUT : undefined
@@ -78,14 +78,14 @@ export const DEFAULT_GLOBAL_SHIMS_PRESET: GlobalShim[] = [
 
 export const MTS_SUPPORTED_NODE_VERSION = 16
 
-const syncFnCache = new Map<string, AnyFn>()
+let syncFnCache: Map<string, AnyFn> | undefined
 
 export interface SynckitOptions {
-  timeout?: number
   execArgv?: string[]
-  tsRunner?: TsRunner
-  transferList?: TransferListItem[]
   globalShims?: GlobalShim[] | boolean
+  timeout?: number
+  transferList?: TransferListItem[]
+  tsRunner?: TsRunner
 }
 
 // MessagePort doesn't copy the properties of Error objects. We still want
@@ -107,16 +107,18 @@ export function createSyncFn<T extends AnyAsyncFn<R>, R = unknown>(
   workerPath: string,
   timeoutOrOptions?: SynckitOptions | number,
 ): Syncify<T> {
-  if (!path.isAbsolute(workerPath)) {
-    throw new Error('`workerPath` must be absolute')
-  }
+  syncFnCache ??= new Map()
 
   const cachedSyncFn = syncFnCache.get(workerPath)
 
   if (cachedSyncFn) {
     return cachedSyncFn as Syncify<T>
   }
 
+  if (!path.isAbsolute(workerPath)) {
+    throw new Error('`workerPath` must be absolute')
+  }
+
   const syncFn = startWorkerThread<R, T>(
     workerPath,
     /* istanbul ignore next */ typeof timeoutOrOptions === 'number'
@@ -309,8 +311,8 @@ export const encodeImportModule = (
               (named === null
                 ? '* as ' + globalName
                 : named?.trim()
-                ? `{${named}}`
-                : globalName) +
+                  ? `{${named}}`
+                  : globalName) +
               ' from'
             : ''
         } '${
@@ -354,7 +356,7 @@ export const _generateGlobals = (
     '',
   )
 
-const globalsCache = new Map<string, [content: string, filepath?: string]>()
+let globalsCache: Map<string, [content: string, filepath?: string]> | undefined
 
 let tmpdir: string
 
@@ -371,6 +373,8 @@ export const generateGlobals = (
   globalShims: GlobalShim[],
   type: 'import' | 'require' = 'import',
 ) => {
+  globalsCache ??= new Map()
+
   const cached = globalsCache.get(workerPath)
 
   if (cached) {
@@ -462,14 +466,17 @@ function startWorkerThread<R, T extends AnyAsyncFn<R>>(
     globalShims === true
       ? DEFAULT_GLOBAL_SHIMS_PRESET
       : Array.isArray(globalShims)
-      ? globalShims
-      : []
+        ? globalShims
+        : []
   ).filter(({ moduleName }) => isPkgAvailable(moduleName))
 
   // We store a single Byte in the SharedArrayBuffer
   // for the notification, we can used a fixed size
-  sharedBuffer ??= new SharedArrayBuffer(INT32_BYTES)
-  sharedBufferView ??= new Int32Array(sharedBuffer, 0, 1)
+  sharedBufferView ??= new Int32Array(
+    (sharedBuffer ??= new SharedArrayBuffer(INT32_BYTES)),
+    0,
+    1,
+  )
 
   const useGlobals = finalGlobalShims.length > 0
 
@@ -484,12 +491,12 @@ function startWorkerThread<R, T extends AnyAsyncFn<R>>(
           )};import '${String(workerPathUrl)}'`,
         )
       : useEval
-      ? `${generateGlobals(
-          finalWorkerPath,
-          finalGlobalShims,
-          'require',
-        )};${encodeImportModule(finalWorkerPath, 'require')}`
-      : workerPathUrl,
+        ? `${generateGlobals(
+            finalWorkerPath,
+            finalGlobalShims,
+            'require',
+          )};${encodeImportModule(finalWorkerPath, 'require')}`
+        : workerPathUrl,
     {
       eval: useEval,
       workerData: { sharedBuffer, workerPort },
@@ -504,9 +511,11 @@ function startWorkerThread<R, T extends AnyAsyncFn<R>>(
     const id = nextID++
 
     const msg: MainToWorkerMessage<Parameters<T>> = { id, args }
+
     worker.postMessage(msg)
 
     const status = Atomics.wait(sharedBufferView!, 0, 0, timeout)
+
     // Reset SharedArrayBuffer for next call
     Atomics.store(sharedBufferView!, 0, 0)
 
@@ -551,6 +560,7 @@ export function runAsWorker<
   }
 
   const { workerPort, sharedBuffer } = workerData as WorkerData
+
   const sharedBufferView = new Int32Array(sharedBuffer, 0, 1)
 
   parentPort!.on(

test/ts-runner.spec.ts

@@ -135,7 +135,7 @@ test('unknown ts runner', async () => {
 
   expect(() =>
     createSyncFn<AsyncWorkerFn>(path.resolve(_dirname, 'worker.js'), {
-      // @ts-expect-error
+      // @ts-expect-error -- intended
       tsRunner: 'unknown',
     }),
   ).toThrowErrorMatchingInlineSnapshot(`"Unknown ts runner: unknown"`)

test/types-d.ts

@@ -8,7 +8,7 @@ import {
   Syncify,
 } from 'synckit'
 
-// @ts-expect-error
+// @ts-expect-error -- intended
 expectType<Syncify<() => 1>>(true)
 
 expectType<TypeEqual<Syncify<() => Promise<true>>, () => true>>(true)
@@ -24,15 +24,15 @@ expectType<() => 1>(createSyncFn<() => Promise<1>>(''))
 expectType<() => true>(createSyncFn<() => Promise<true>>(''))
 expectType<() => true>(createSyncFn<() => Promise<never>>(''))
 
-// @ts-expect-error
+// @ts-expect-error -- intended
 createSyncFn<() => 0>('')
 
 expectType<void>(runAsWorker(() => Promise.resolve(1)))
 
-// @ts-expect-error
+// @ts-expect-error -- intended
 runAsWorker(() => 1)
 
 runAsWorker<() => Promise<string>>(() =>
-  // @ts-expect-error
+  // @ts-expect-error -- intended
   Promise.resolve(1),
 )