fix(jest-resolve): cache package.json lookups (#11076)

CHANGELOG.md

@@ -84,6 +84,7 @@
 
 ### Performance
 
+- `[jest-resolve]` Cache reading and parsing of `package.json`s ([#11076](https://github.com/facebook/jest/pull/11076))
 - `[jest-runtime]` Load `chalk` only once per worker ([#10864](https://github.com/facebook/jest/pull/10864))
 
 ## 26.6.3

e2e/__tests__/__snapshots__/moduleNameMapper.test.ts.snap

@@ -41,7 +41,7 @@ FAIL __tests__/index.js
       12 | module.exports = () => 'test';
       13 |
 
-      at createNoMappedModuleFoundError (../../packages/jest-resolve/build/index.js:556:17)
+      at createNoMappedModuleFoundError (../../packages/jest-resolve/build/index.js:558:17)
       at Object.require (index.js:10:1)
 `;
 
@@ -70,6 +70,6 @@ FAIL __tests__/index.js
       12 | module.exports = () => 'test';
       13 |
 
-      at createNoMappedModuleFoundError (../../packages/jest-resolve/build/index.js:556:17)
+      at createNoMappedModuleFoundError (../../packages/jest-resolve/build/index.js:558:17)
       at Object.require (index.js:10:1)
 `;

packages/jest-resolve/package.json

@@ -20,12 +20,12 @@
     "graceful-fs": "^4.2.4",
     "jest-pnp-resolver": "^1.2.2",
     "jest-util": "^27.0.0-next.1",
-    "resolve": "^1.18.1",
+    "resolve": "^1.20.0",
     "slash": "^3.0.0"
   },
   "devDependencies": {
     "@types/graceful-fs": "^4.1.3",
-    "@types/resolve": "^1.17.0",
+    "@types/resolve": "^1.20.0",
     "jest-haste-map": "^27.0.0-next.2"
   },
   "engines": {

packages/jest-resolve/src/defaultResolver.ts

@@ -7,7 +7,7 @@
 
 import * as fs from 'graceful-fs';
 import pnpResolver from 'jest-pnp-resolver';
-import {Opts as ResolveOpts, sync as resolveSync} from 'resolve';
+import {sync as resolveSync} from 'resolve';
 import type {Config} from '@jest/types';
 import {tryRealpath} from 'jest-util';
 
@@ -19,7 +19,7 @@ type ResolverOptions = {
   moduleDirectory?: Array<string>;
   paths?: Array<Config.Path>;
   rootDir?: Config.Path;
-  packageFilter?: ResolveOpts['packageFilter'];
+  packageFilter?: (pkg: any, pkgfile: string) => any;
 };
 
 // https://github.com/facebook/jest/pull/10617
@@ -50,6 +50,7 @@ export default function defaultResolver(
     packageFilter: options.packageFilter,
     paths: options.paths,
     preserveSymlinks: false,
+    readPackageSync,
     realpathSync,
   });
 
@@ -61,6 +62,7 @@ export default function defaultResolver(
 export function clearDefaultResolverCache(): void {
   checkedPaths.clear();
   checkedRealpathPaths.clear();
+  packageContents.clear();
 }
 
 enum IPathType {
@@ -118,6 +120,23 @@ function realpathCached(path: Config.Path): Config.Path {
   return result;
 }
 
+type PkgJson = Record<string, unknown>;
+
+const packageContents = new Map<string, PkgJson>();
+function readPackageCached(path: Config.Path): PkgJson {
+  let result = packageContents.get(path);
+
+  if (result !== undefined) {
+    return result;
+  }
+
+  result = JSON.parse(fs.readFileSync(path, 'utf8')) as PkgJson;
+
+  packageContents.set(path, result);
+
+  return result;
+}
+
 /*
  * helper functions
  */
@@ -132,3 +151,7 @@ function isDirectory(dir: Config.Path): boolean {
 function realpathSync(file: Config.Path): Config.Path {
   return realpathCached(file);
 }
+
+function readPackageSync(_: unknown, file: Config.Path): PkgJson {
+  return readPackageCached(file);
+}

packages/jest-resolve/src/index.ts

@@ -48,7 +48,7 @@ const nodePaths = NODE_PATH
       .map(p => path.resolve(resolvedCwd, p))
   : undefined;
 
-class Resolver {
+export default class Resolver {
   private readonly _options: ResolverConfig;
   private readonly _moduleMap: ModuleMap;
   private readonly _moduleIDCache: Map<string, string>;
@@ -495,5 +495,3 @@ Please check your configuration for these entries:
 
   return error;
 };
-
-export default Resolver;

packages/jest-runtime/src/index.ts

@@ -271,7 +271,7 @@ export default class Runtime {
 
   static shouldInstrument = shouldInstrument;
 
-  static createContext(
+  static async createContext(
     config: Config.ProjectConfig,
     options: {
       console?: Console;
@@ -288,17 +288,14 @@ export default class Runtime {
       watch: options.watch,
       watchman: options.watchman,
     });
-    return instance.build().then(
-      hasteMap => ({
-        config,
-        hasteFS: hasteMap.hasteFS,
-        moduleMap: hasteMap.moduleMap,
-        resolver: Runtime.createResolver(config, hasteMap.moduleMap),
-      }),
-      error => {
-        throw error;
-      },
-    );
+    const hasteMap = await instance.build();
+
+    return {
+      config,
+      hasteFS: hasteMap.hasteFS,
+      moduleMap: hasteMap.moduleMap,
+      resolver: Runtime.createResolver(config, hasteMap.moduleMap),
+    };
   }
 
   static createHasteMap(

yarn.lock

@@ -3830,12 +3830,10 @@ __metadata:
   languageName: node
   linkType: hard
 
-"@types/resolve@npm:^1.17.0":
-  version: 1.19.0
-  resolution: "@types/resolve@npm:1.19.0"
-  dependencies:
-    "@types/node": "*"
-  checksum: 6dab5d4bf568d4fe7ed2207f839736d3558e04f994cdad122ce3c0a3d75f56080f4f63a297d5dcf61a1d3f450ebb99a8ca3719e3b7147c863d80436f1a9890e2
+"@types/resolve@npm:^1.20.0":
+  version: 1.20.0
+  resolution: "@types/resolve@npm:1.20.0"
+  checksum: 3c75135d5cf3652453ef8f099b109f7fec5e82fe67bf38048226614dbcd11a943affee383e5d28c12c5f03b049281a3e486395326b9810297f9649c7b00f41fd
   languageName: node
   linkType: hard
 
@@ -12067,14 +12065,14 @@ fsevents@^1.2.7:
   dependencies:
     "@jest/types": ^27.0.0-next.1
     "@types/graceful-fs": ^4.1.3
-    "@types/resolve": ^1.17.0
+    "@types/resolve": ^1.20.0
     chalk: ^4.0.0
     escalade: ^3.1.1
     graceful-fs: ^4.2.4
     jest-haste-map: ^27.0.0-next.2
     jest-pnp-resolver: ^1.2.2
     jest-util: ^27.0.0-next.1
-    resolve: ^1.18.1
+    resolve: ^1.20.0
     slash: ^3.0.0
   languageName: unknown
   linkType: soft
@@ -17276,7 +17274,7 @@ react-native@0.63.2:
   languageName: node
   linkType: hard
 
-"resolve@^1.1.6, resolve@^1.10.0, resolve@^1.13.1, resolve@^1.15.0, resolve@^1.17.0, resolve@^1.18.1, resolve@^1.5.0":
+"resolve@^1.1.6, resolve@^1.10.0, resolve@^1.13.1, resolve@^1.15.0, resolve@^1.17.0, resolve@^1.20.0, resolve@^1.5.0":
   version: 1.20.0
   resolution: "resolve@npm:1.20.0"
   dependencies:
@@ -17286,7 +17284,7 @@ react-native@0.63.2:
   languageName: node
   linkType: hard
 
-"resolve@patch:resolve@^1.1.6#builtin<compat/resolve>, resolve@patch:resolve@^1.10.0#builtin<compat/resolve>, resolve@patch:resolve@^1.13.1#builtin<compat/resolve>, resolve@patch:resolve@^1.15.0#builtin<compat/resolve>, resolve@patch:resolve@^1.17.0#builtin<compat/resolve>, resolve@patch:resolve@^1.18.1#builtin<compat/resolve>, resolve@patch:resolve@^1.5.0#builtin<compat/resolve>":
+"resolve@patch:resolve@^1.1.6#builtin<compat/resolve>, resolve@patch:resolve@^1.10.0#builtin<compat/resolve>, resolve@patch:resolve@^1.13.1#builtin<compat/resolve>, resolve@patch:resolve@^1.15.0#builtin<compat/resolve>, resolve@patch:resolve@^1.17.0#builtin<compat/resolve>, resolve@patch:resolve@^1.20.0#builtin<compat/resolve>, resolve@patch:resolve@^1.5.0#builtin<compat/resolve>":
   version: 1.20.0
   resolution: "resolve@patch:resolve@npm%3A1.20.0#builtin<compat/resolve>::version=1.20.0&hash=3388aa"
   dependencies: