fix: retry writing traced files if there are conflicts (nitrojs#537)

src/rollup/plugins/externals.ts

@@ -5,7 +5,7 @@ import { nodeFileTrace, NodeFileTraceOptions } from '@vercel/nft'
 import type { Plugin } from 'rollup'
 import { resolvePath, isValidNodeImport, normalizeid } from 'mlly'
 import semver from 'semver'
-import { isDirectory } from '../../utils'
+import { isDirectory, retry } from '../../utils'
 
 export interface NodeExternalsOptions {
   inline?: string[]
@@ -220,7 +220,7 @@ export function externals (opts: NodeExternalsOptions): Plugin {
         }
       }
 
-      const writeFile = async (file) => {
+      const writeFile = async (file: string) => {
         if (!await isFile(file)) { return }
         const src = resolve(opts.traceOptions.base, file)
         const { pkgName, subpath } = parseNodeModulePath(file)
@@ -230,7 +230,7 @@ export function externals (opts: NodeExternalsOptions): Plugin {
       }
 
       // Write traced files
-      await Promise.all(tracedFiles.map(writeFile))
+      await Promise.all(tracedFiles.map(file => retry(() => writeFile(file), 3)))
 
       // Write an informative package.json
       await fsp.writeFile(resolve(opts.outDir, 'package.json'), JSON.stringify({

src/utils/index.ts

@@ -146,3 +146,15 @@ export function resolveAliases (_aliases: Record<string, string>) {
   }
   return aliases
 }
+
+export async function retry (fn: () => Promise<void>, retries: number) {
+  let retry = 0
+  let error: any
+  while (retry++ < retries) {
+    try { return await fn() } catch (err) {
+      error = err
+      await new Promise(resolve => setTimeout(resolve, 2))
+    }
+  }
+  throw error
+}

test/unit/utils.test.ts

@@ -0,0 +1,22 @@
+import { describe, it, expect } from 'vitest'
+import { retry } from '../../src/utils'
+
+describe('retry', () => {
+  it('retries function', async () => {
+    let counter = 0
+    // eslint-disable-next-line require-await
+    const fn = async () => {
+      if (!counter++) {
+        throw new Error('deliberate')
+      }
+    }
+
+    await retry(fn, 3)
+    expect(counter).toEqual(2)
+  })
+  it('throws function', async () => {
+    // eslint-disable-next-line require-await
+    const fn = async () => { throw new Error('deliberate') }
+    expect(await retry(fn, 2).catch(() => 'thrown')).toEqual('thrown')
+  })
+})