feat(yarn-cling): support yarn berry lockfiles using @yarnpkg/parsers

.projenrc.ts

@@ -592,8 +592,8 @@ const yarnCling = configureProject(
     name: '@aws-cdk/yarn-cling',
     description: 'Tool for generating npm-shrinkwrap from yarn.lock',
     srcdir: 'lib',
-    deps: ['@yarnpkg/lockfile', 'semver'],
-    devDeps: ['@types/semver', '@types/yarnpkg__lockfile', 'fast-check'],
+    deps: ['@yarnpkg/parsers', 'semver'],
+    devDeps: ['@types/semver', 'fast-check'],
     minNodeVersion: '18',
     tsconfig: {
       compilerOptions: {
@@ -610,6 +610,7 @@ const yarnCling = configureProject(
   }),
 );
 yarnCling.testTask.prependExec('ln -sf ../../cdk test/test-fixture/jsii/node_modules/');
+yarnCling.testTask.prependExec('ln -sf ../../cdk test/test-fixture-berry/jsii/node_modules/');
 
 // #endregion
 //////////////////////////////////////////////////////////////////////

packages/@aws-cdk/yarn-cling/lib/index.ts

@@ -1,10 +1,10 @@
-import { promises as fs, exists } from 'fs';
+import { promises as fs } from 'fs';
 import * as os from 'os';
 import * as path from 'path';
-import * as lockfile from '@yarnpkg/lockfile';
+import { parseSyml } from '@yarnpkg/parsers';
 import * as semver from 'semver';
 import { hoistDependencies } from './hoisting';
-import { isPackage, iterDeps, type PackageJson, type PackageLockFile, type PackageLockPackage, type PackageLockTree, type YarnLock } from './types';
+import { isPackage, iterDeps, type PackageJson, type PackageLockFile, type PackageLockPackage, type PackageLockTree, type ResolvedYarnPackage, type YarnLock } from './types';
 
 export interface ShrinkwrapOptions {
   /**
@@ -33,7 +33,7 @@ export async function generateShrinkwrap(options: ShrinkwrapOptions): Promise<Pa
   const packageJsonDir = path.dirname(packageJsonFile);
 
   const yarnLockLoc = await findYarnLock(packageJsonDir);
-  const yarnLock: YarnLock = lockfile.parse(await fs.readFile(yarnLockLoc, { encoding: 'utf8' }));
+  const yarnLock: YarnLock = parseYarnLock(await fs.readFile(yarnLockLoc, { encoding: 'utf8' }));
   const pkgJson = await loadPackageJson(packageJsonFile);
 
   let lock = await generateLockFile(pkgJson, yarnLock, packageJsonDir);
@@ -52,6 +52,55 @@ export async function generateShrinkwrap(options: ShrinkwrapOptions): Promise<Pa
   return lock;
 }
 
+/**
+ * Parse a yarn.lock file, supporting both classic (v1) and berry (v2+) formats.
+ */
+export function parseYarnLock(content: string): YarnLock {
+  const parsed = parseSyml(content);
+
+  // Berry lockfiles have __metadata and use different field names
+  if (parsed.__metadata) {
+    return convertBerryToClassicLock(parsed);
+  }
+
+  // Classic v1 lockfiles are already in the right shape
+  return { type: 'success', object: parsed };
+}
+
+/**
+ * Convert a parsed berry (v2+) lockfile into the classic YarnLock format.
+ *
+ * Berry keys look like: "pkg@npm:^1.0.0" or "pkg@npm:^1.0.0, pkg@npm:^2.0.0"
+ * We convert each to the classic format: "pkg@^1.0.0" -> { version, resolved, integrity, dependencies }
+ */
+function convertBerryToClassicLock(parsed: Record<string, any>): YarnLock {
+  const object: Record<string, ResolvedYarnPackage> = Object.create(null);
+
+  for (const [key, entry] of Object.entries(parsed)) {
+    if (key === '__metadata' || !entry?.version) continue;
+
+    const resolved: ResolvedYarnPackage = {
+      version: entry.version,
+      ...(entry.resolution && { resolved: entry.resolution }),
+      ...(entry.checksum && { integrity: entry.checksum }),
+      ...(entry.dependencies && {
+        dependencies: Object.fromEntries(
+          Object.entries(entry.dependencies).map(([k, v]: [string, any]) => [k, String(v).replace(/^npm:/, '')]),
+        ),
+      }),
+    };
+
+    // Convert berry descriptors ("pkg@npm:^1.0.0") to classic format ("pkg@^1.0.0")
+    for (const descriptor of key.split(', ')) {
+      const npmMatch = descriptor.match(/^(.+)@npm:(.+)$/);
+      const classicKey = npmMatch ? `${npmMatch[1]}@${npmMatch[2]}` : descriptor;
+      object[classicKey] = resolved;
+    }
+  }
+
+  return { type: 'success', object };
+}
+
 async function generateLockFile(pkgJson: PackageJson, yarnLock: YarnLock, rootDir: string): Promise<PackageLockFile> {
   const builder = new PackageGraphBuilder(yarnLock);
   const rootKeys = await builder.buildGraph(pkgJson.dependencies || {}, rootDir);
@@ -321,7 +370,7 @@ async function findPackageDir(depName: string, rootDir: string) {
   let dir = rootDir;
   while (dir !== prevDir) {
     const candidateDir = path.join(dir, 'node_modules', depName);
-    if (await new Promise(ok => exists(path.join(candidateDir, 'package.json'), ok))) {
+    if (await fileExists(path.join(candidateDir, 'package.json'))) {
       return candidateDir;
     }
 

packages/@aws-cdk/yarn-cling/test/cling.test.ts

@@ -1,5 +1,5 @@
 import * as path from 'path';
-import { checkRequiredVersions, generateShrinkwrap } from '../lib';
+import { checkRequiredVersions, generateShrinkwrap, parseYarnLock } from '../lib';
 
 test('generate lock for fixture directory', async () => {
   const lockFile = await generateShrinkwrap({
@@ -86,3 +86,58 @@ test('fail when requires cannot be satisfied', async () => {
 
   expect(() => checkRequiredVersions(lockFile)).toThrow(/NPM will not respect/);
 });
+
+test('generate lock for berry fixture directory', async () => {
+  const lockFile = await generateShrinkwrap({
+    packageJsonFile: path.join(__dirname, 'test-fixture-berry', 'jsii', 'package.json'),
+    hoist: false,
+  });
+
+  expect(lockFile).toEqual({
+    lockfileVersion: 1,
+    name: 'jsii',
+    requires: true,
+    version: '1.1.1',
+    dependencies: {
+      'cdk': {
+        version: '2.2.2',
+      },
+      'aws-cdk': {
+        integrity: '10/banana',
+        requires: {
+          'aws-cdk-lib': '^2.3.4',
+        },
+        resolved: 'aws-cdk@npm:1.2.999',
+        version: '1.2.999',
+      },
+      'aws-cdk-lib': {
+        integrity: '10-pineapple',
+        resolved: 'aws-cdk-lib@npm:2.3.999',
+        version: '2.3.999',
+      },
+    },
+  });
+});
+
+test('parseBerryLockfile converts berry format to classic YarnLock', () => {
+  const berryContent = [
+    '__metadata:',
+    '  version: 8',
+    '',
+    '"foo@npm:^1.0.0":',
+    '  version: 1.2.3',
+    '  resolution: "foo@npm:1.2.3"',
+    '  checksum: 10-abc123',
+    '  languageName: node',
+    '  linkType: hard',
+    '',
+  ].join('\n');
+
+  const result = parseYarnLock(berryContent);
+  expect(result.type).toBe('success');
+  expect(result.object['foo@^1.0.0']).toEqual({
+    version: '1.2.3',
+    resolved: 'foo@npm:1.2.3',
+    integrity: '10-abc123',
+  });
+});

packages/@aws-cdk/yarn-cling/test/test-fixture-berry/.gitignore

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

packages/@aws-cdk/yarn-cling/test/test-fixture-berry/.no-packagejson-validator

@@ -0,0 +1 @@
+Test fixtures should not be affected.

packages/@aws-cdk/yarn-cling/test/test-fixture-berry/cdk/package.json

@@ -0,0 +1,4 @@
+{
+    "name": "cdk",
+    "version": "2.2.2"
+}

packages/@aws-cdk/yarn-cling/test/test-fixture-berry/jsii/package.json

@@ -0,0 +1,8 @@
+{
+    "name": "jsii",
+    "version": "1.1.1",
+    "dependencies": {
+        "aws-cdk": "^1.2.3",
+        "cdk": "2.2.2"
+    }
+}

packages/@aws-cdk/yarn-cling/test/test-fixture-berry/yarn.lock

@@ -0,0 +1,22 @@
+# This file is generated by running "yarn install" inside your project.
+# Manual changes might be lost - proceed with caution!
+
+__metadata:
+  version: 8
+  cacheKey: 10
+
+"aws-cdk@npm:^1.2.3":
+  version: 1.2.999
+  resolution: "aws-cdk@npm:1.2.999"
+  dependencies:
+    aws-cdk-lib: "npm:^2.3.4"
+  checksum: 10/banana
+  languageName: node
+  linkType: hard
+
+"aws-cdk-lib@npm:^2.3.4":
+  version: 2.3.999
+  resolution: "aws-cdk-lib@npm:2.3.999"
+  checksum: 10-pineapple
+  languageName: node
+  linkType: hard

packages/@aws-cdk/yarn-cling/test/test-fixture/yarn.lock

@@ -1,3 +1,6 @@
+# THIS IS AN AUTOGENERATED FILE. DO NOT EDIT THIS FILE DIRECTLY.
+# yarn lockfile v1
+
 "aws-cdk@^1.2.3":
   version "1.2.999"
   resolved "https://registry.bla.com/stuff"