Refactor: Bun.peek polyfill for Node.js

Build/build-speedtest-domainset.ts

@@ -13,6 +13,7 @@ import { readFileIntoProcessedArray } from './lib/fetch-text-by-line';
 import { TTL, deserializeArray, fsFetchCache, serializeArray } from './lib/cache-filesystem';
 
 import { createTrie } from './lib/trie';
+import { peek } from './lib/bun';
 
 const s = new Sema(2);
 
@@ -239,7 +240,7 @@ export const buildSpeedtestDomainSet = task(import.meta.main, import.meta.path)(
     const timer = setTimeout(() => {
       console.error(picocolors.red('Task timeout!'));
       Object.entries(pMap).forEach(([name, p]) => {
-        console.log(`[${name}]`, Bun.peek.status(p));
+        console.log(`[${name}]`, peek.status(p));
       });
 
       resolve();

Build/download-previous-build.ts

@@ -33,7 +33,6 @@ export const downloadPreviousBuild = task(import.meta.main, import.meta.path)(as
         buildOutputList.push(line);
 
         if (!isCI) {
-          // Bun.file().exists() doesn't check directory
           if (!existsSync(path.join(import.meta.dir, '..', line))) {
             flag = flag & ~ALL_FILES_EXISTS;
           }

Build/lib/bun.ts

@@ -0,0 +1,13 @@
+interface Peek {
+  <T = undefined>(promise: T | Promise<T>): Promise<T> | T,
+  status<T = undefined>(
+    promise: T | Promise<T>,
+  ): 'pending' | 'fulfilled' | 'rejected' | 'unknown'
+}
+
+const noopPeek = <T = undefined>(_: Promise<T>) => _;
+noopPeek.status = () => 'unknown';
+
+export const peek: Peek = typeof Bun !== 'undefined'
+  ? Bun.peek
+  : noopPeek as Peek;

Build/lib/cache-filesystem.ts

@@ -5,6 +5,7 @@ import path from 'path';
 import { mkdirSync } from 'fs';
 import picocolors from 'picocolors';
 import { fastStringArrayJoin } from './misc';
+import { peek } from 'bun';
 
 const identity = (x: any) => x;
 
@@ -178,7 +179,7 @@ export class Cache<S = string> {
       const serializer = 'serializer' in opt ? opt.serializer : identity;
 
       const promise = fn();
-      const peeked = Bun.peek(promise);
+      const peeked = peek(promise);
 
       if (peeked === promise) {
         return promise.then((value) => {