feat: prepare for yarn v2 feature

.gitignore

@@ -6,4 +6,3 @@ dist
 .eslintcache
 *.log
 /package-lock.json
-.idea

lib/index.ts

@@ -14,7 +14,6 @@ import {
 } from './parsers';
 import { PackageLockParser } from './parsers/package-lock-parser';
 import { YarnLockParser } from './parsers/yarn-lock-parse';
-import { Yarn2LockParser } from './parsers/yarn2-lock-parse';
 import getRuntimeVersion from './get-node-runtime-version';
 import {
   UnsupportedRuntimeError,
@@ -64,18 +63,6 @@ async function buildDepTree(
         );
       }
       break;
-    case LockfileType.yarn2:
-      // parsing yarn.lock is supported for Node.js v10 and higher
-      if (getRuntimeVersion() >= 10) {
-        lockfileParser = new Yarn2LockParser();
-      } else {
-        throw new UnsupportedRuntimeError(
-          'Parsing `yarn.lock` is not ' +
-            'supported on Node.js version less than 10. Please upgrade your ' +
-            'Node.js environment or use `package-lock.json`',
-        );
-      }
-      break;
     default:
       throw new InvalidUserInputError(
         'Unsupported lockfile type ' +
@@ -113,15 +100,7 @@ async function buildDepTreeFromFiles(
   if (_.endsWith(lockFilePath, 'package-lock.json')) {
     lockFileType = LockfileType.npm;
   } else if (_.endsWith(lockFilePath, 'yarn.lock')) {
-    if (
-      fs.existsSync(
-        path.resolve(root, lockFilePath.replace('yarn.lock', '.yarnrc.yml')),
-      )
-    ) {
-      lockFileType = LockfileType.yarn2;
-    } else {
-      lockFileType = LockfileType.yarn;
-    }
+    lockFileType = LockfileType.yarn;
   } else {
     throw new InvalidUserInputError(
       `Unknown lockfile ${lockFilePath}. ` +

lib/parsers/index.ts

@@ -2,7 +2,6 @@ import * as _ from 'lodash';
 import { PackageLock } from './package-lock-parser';
 import { YarnLock } from './yarn-lock-parse';
 import { InvalidUserInputError } from '../errors';
-import { Yarn2Lock } from './yarn2-lock-parse';
 
 export interface Dep {
   name: string;
@@ -65,7 +64,6 @@ export enum Scope {
 export enum LockfileType {
   npm = 'npm',
   yarn = 'yarn',
-  yarn2 = 'yarn2',
 }
 
 export interface LockfileParser {
@@ -78,7 +76,7 @@ export interface LockfileParser {
   ) => Promise<PkgTree>;
 }
 
-export type Lockfile = PackageLock | YarnLock | Yarn2Lock;
+export type Lockfile = PackageLock | YarnLock;
 
 export function parseManifestFile(manifestFileContents: string): ManifestFile {
   try {

lib/parsers/yarn-lock-parse-base.ts

@@ -22,7 +22,7 @@ import { config } from '../config';
 
 const EVENT_PROCESSING_CONCURRENCY = 5;
 
-export type YarnLockFileTypes = LockfileType.yarn | LockfileType.yarn2;
+export type YarnLockFileTypes = LockfileType.yarn;
 
 export interface YarnLockDeps {
   [depName: string]: YarnLockDep;
@@ -112,7 +112,7 @@ export abstract class YarnLockParseBase<T extends YarnLockFileTypes>
       const dependency = lockFile.object[depKey];
       if (!dependency) {
         if (strict) {
-          throw new OutOfSyncError(queueItem.tree.name!, 'yarn');
+          throw new OutOfSyncError(queueItem.tree.name!, this.type);
         }
         if (!queueItem.tree.labels) {
           queueItem.tree.labels = {};

lib/parsers/yarn-lock-parse.ts

@@ -1,38 +1,26 @@
+import * as yarnLockfileParser from '@yarnpkg/lockfile';
+
 import { LockfileType } from './';
-import getRuntimeVersion from '../get-node-runtime-version';
-import { InvalidUserInputError, UnsupportedRuntimeError } from '../errors';
+import { InvalidUserInputError } from '../errors';
 import { YarnLockBase } from './yarn-lock-parse-base';
 import { YarnLockParseBase } from './yarn-lock-parse-base';
 
 export type YarnLock = YarnLockBase<LockfileType.yarn>;
 
 export class YarnLockParser extends YarnLockParseBase<LockfileType.yarn> {
-  private yarnLockfileParser: any;
-
   constructor() {
     super(LockfileType.yarn);
-    // @yarnpkg/lockfile doesn't work with Node.js < 6 and crashes just after
-    // the import, so it has to be required conditionally
-    // more details at https://github.com/yarnpkg/yarn/issues/6304
-    if (getRuntimeVersion() < 6) {
-      throw new UnsupportedRuntimeError(
-        'yarn.lock parsing is supported for ' + 'Node.js v6 and higher.',
-      );
-    }
-    this.yarnLockfileParser = require('@yarnpkg/lockfile');
   }
 
   public parseLockFile(lockFileContents: string): YarnLock {
     try {
-      const yarnLock: YarnLock = this.yarnLockfileParser.parse(
-        lockFileContents,
-      );
+      const yarnLock: YarnLock = yarnLockfileParser.parse(lockFileContents);
       yarnLock.dependencies = yarnLock.object;
       yarnLock.type = LockfileType.yarn;
       return yarnLock;
     } catch (e) {
       throw new InvalidUserInputError(
-        'yarn.lock parsing failed with an ' + `error: ${e.message}`,
+        `yarn.lock parsing failed with an error: ${e.message}`,
       );
     }
   }

package.json

@@ -30,7 +30,6 @@
   ],
   "homepage": "https://github.com/snyk/nodejs-lockfile-parser#readme",
   "dependencies": {
-    "@yarnpkg/core": "^2.0.0-rc.26",
     "@yarnpkg/lockfile": "^1.0.2",
     "event-loop-spinner": "^1.1.0",
     "graphlib": "^2.1.5",
@@ -39,8 +38,7 @@
     "snyk-config": "^3.0.0",
     "source-map-support": "^0.5.7",
     "tslib": "^1.9.3",
-    "uuid": "^3.3.2",
-    "yaml": "^1.9.2"
+    "uuid": "^3.3.2"
   },
   "devDependencies": {
     "@types/graphlib": "^2.1.4",