fix(optimizer): fall back to yarn.lock for lockfile hash (#23667)

Co-authored-by: sapphi-red <green@sapphi.red>

Author: aotradovec

packages/vite/src/node/__tests__/optimizer/fixtures/lockfile-hash/yarn-lock/yarn.lock

@@ -0,0 +1 @@
+foo@1.0.0:

packages/vite/src/node/__tests__/optimizer/fixtures/lockfile-hash/yarn-state/.gitignore

@@ -0,0 +1 @@
+!/node_modules/

packages/vite/src/node/__tests__/optimizer/fixtures/lockfile-hash/yarn-state/node_modules/.yarn-state.yml

@@ -0,0 +1 @@
+foo@1.0.0:

packages/vite/src/node/__tests__/optimizer/fixtures/lockfile-hash/yarn-state/yarn.lock

@@ -0,0 +1,36 @@
+import fs from 'node:fs'
+import os from 'node:os'
+import path from 'node:path'
+import { beforeAll, expect, test } from 'vitest'
+import { getLockfileHash } from '../../optimizer'
+import { getHash } from '../../utils'
+
+const fixturesDir = path.join(import.meta.dirname, 'fixtures/lockfile-hash')
+let root: string
+
+beforeAll(() => {
+  // Copy outside the repo so lookup does not find the repo's own lockfile.
+  root = fs.mkdtempSync(
+    path.join(fs.realpathSync(os.tmpdir()), 'vite-lockfile-hash-'),
+  )
+  fs.cpSync(fixturesDir, root, { recursive: true })
+  return () => {
+    fs.rmSync(root, { recursive: true, force: true })
+  }
+})
+
+test('falls back to yarn.lock when no lockfile is found in node_modules', () => {
+  const fixture = path.join(root, 'yarn-lock')
+  const content = fs.readFileSync(path.join(fixture, 'yarn.lock'))
+
+  expect(getLockfileHash(fixture)).toBe(getHash(content))
+})
+
+test('prefers lockfiles in node_modules over yarn.lock', () => {
+  const fixture = path.join(root, 'yarn-state')
+  const content = fs.readFileSync(
+    path.join(fixture, 'node_modules/.yarn-state.yml'),
+  )
+
+  expect(getLockfileHash(fixture)).toBe(getHash(content))
+})

packages/vite/src/node/__tests__/optimizer/lockfileHash.spec.ts

@@ -418,7 +418,9 @@ export async function loadCachedDepOptimizationMetadata(
     } catch {}
     // hash is consistent, no need to re-bundle
     if (cachedMetadata) {
-      if (cachedMetadata.lockfileHash !== getLockfileHash(environment)) {
+      if (
+        cachedMetadata.lockfileHash !== getLockfileHash(environment.config.root)
+      ) {
         environment.logger.info(
           'Re-optimizing dependencies because lockfile has changed',
           {
@@ -1299,6 +1301,18 @@ const lockfileFormats = [
 })
 const lockfilePaths = lockfileFormats.map((l) => l.path)
 
+// Only used when none of the formats above is found, so it never changes which
+// lockfile is hashed for projects that already have one of them.
+// e.g. Yarn with `nodeLinker: pnpm` writes neither `.yarn-state.yml` nor `.pnp.cjs`.
+const fallbackLockfileFormats = [
+  {
+    path: 'yarn.lock',
+    checkPatchesDir: '.yarn/patches',
+    manager: 'yarn',
+  },
+]
+const fallbackLockfilePaths = fallbackLockfileFormats.map((l) => l.path)
+
 function getConfigHash(environment: Environment): string {
   // Take config into account
   // only a subset of config options that can affect dep optimization
@@ -1344,14 +1358,16 @@ function getConfigHash(environment: Environment): string {
   return getHash(content)
 }
 
-function getLockfileHash(environment: Environment): string {
-  const lockfilePath = lookupFile(environment.config.root, lockfilePaths)
+export function getLockfileHash(root: string): string {
+  const lockfilePath =
+    lookupFile(root, lockfilePaths) ?? lookupFile(root, fallbackLockfilePaths)
   let content = lockfilePath ? fs.readFileSync(lockfilePath, 'utf-8') : ''
   if (lockfilePath) {
     const normalizedLockfilePath = lockfilePath.replaceAll('\\', '/')
-    const lockfileFormat = lockfileFormats.find((f) =>
-      normalizedLockfilePath.endsWith(f.path),
-    )!
+    const lockfileFormat = [
+      ...lockfileFormats,
+      ...fallbackLockfileFormats,
+    ].find((f) => normalizedLockfilePath.endsWith(f.path))!
     if (lockfileFormat.checkPatchesDir) {
       // Default of https://github.com/ds300/patch-package
       const baseDir = lockfilePath.slice(0, -lockfileFormat.path.length)
@@ -1373,7 +1389,7 @@ function getDepHash(environment: Environment): {
   configHash: string
   hash: string
 } {
-  const lockfileHash = getLockfileHash(environment)
+  const lockfileHash = getLockfileHash(environment.config.root)
   const configHash = getConfigHash(environment)
   const hash = getHash(lockfileHash + configHash)
   return {