add 'preserveLoadOrder' flag and e2e tests

e2e/esm-load-order/__tests__/test.js

@@ -0,0 +1,4 @@
+import '../esm-package';
+import '../cjs-package';
+
+it('load order is preserved', () => expect(Registrar['esm-package']).toEqual({}));

e2e/esm-load-order/cjs-package/index.cjs

@@ -0,0 +1 @@
+require('../esm-package/index.cjs');

e2e/esm-load-order/cjs-package/package.json

@@ -0,0 +1,4 @@
+{
+  "type": "commonjs",
+  "main": "./index.cjs"
+}

e2e/esm-load-order/esm-package/index.cjs

@@ -0,0 +1 @@
+module.exports = Registrar['esm-package'];

e2e/esm-load-order/esm-package/index.js

@@ -0,0 +1,3 @@
+globalThis.Registrar = {};
+
+Registrar['esm-package'] = {};

e2e/esm-load-order/esm-package/package.json

@@ -0,0 +1,11 @@
+{
+  "type": "module",
+  "exports": {
+    ".": {
+      "node": {
+        "require": "./index.cjs",
+        "import": "./index.js"
+      }
+    }
+  }
+}

e2e/esm-load-order/package.json

@@ -0,0 +1,8 @@
+{
+  "type": "module",
+  "jest": {
+    "transform": {},
+    "testEnvironment": "node",
+    "preserveLoadOrder": true
+  }
+}

packages/jest-config/src/Defaults.ts

@@ -64,6 +64,7 @@ const defaultOptions: Config.DefaultOptions = {
   notifyMode: 'failure-change',
   openHandlesTimeout: 1000,
   passWithNoTests: false,
+  preserveLoadOrder: false,
   prettierPath: 'prettier',
   resetMocks: false,
   resetModules: false,

packages/jest-config/src/ValidConfig.ts

@@ -120,6 +120,7 @@ export const initialOptions: Config.InitialOptions = {
   onlyFailures: false,
   openHandlesTimeout: 1000,
   passWithNoTests: false,
+  preserveLoadOrder: false,
   preset: 'react-native',
   prettierPath: '<rootDir>/node_modules/prettier',
   projects: ['project-a', 'project-b/'],
@@ -279,6 +280,7 @@ export const initialProjectOptions: Config.InitialProjectOptions = {
   modulePathIgnorePatterns: ['<rootDir>/build/'],
   modulePaths: ['/shared/vendor/modules'],
   openHandlesTimeout: 1000,
+  preserveLoadOrder: false,
   preset: 'react-native',
   prettierPath: '<rootDir>/node_modules/prettier',
   reporters: [

packages/jest-config/src/index.ts

@@ -116,6 +116,7 @@ const groupOptions = (
     openHandlesTimeout: options.openHandlesTimeout,
     outputFile: options.outputFile,
     passWithNoTests: options.passWithNoTests,
+    preserveLoadOrder: options.preserveLoadOrder,
     projects: options.projects,
     randomize: options.randomize,
     replname: options.replname,
@@ -178,6 +179,7 @@ const groupOptions = (
     modulePathIgnorePatterns: options.modulePathIgnorePatterns,
     modulePaths: options.modulePaths,
     openHandlesTimeout: options.openHandlesTimeout,
+    preserveLoadOrder: options.preserveLoadOrder,
     prettierPath: options.prettierPath,
     reporters: options.reporters,
     resetMocks: options.resetMocks,

packages/jest-config/src/normalize.ts

@@ -922,6 +922,7 @@ export default async function normalize(
       case 'openHandlesTimeout':
       case 'outputFile':
       case 'passWithNoTests':
+      case 'preserveLoadOrder':
       case 'randomize':
       case 'replname':
       case 'resetMocks':

packages/jest-runtime/src/index.ts

@@ -758,23 +758,32 @@ export default class Runtime {
     }
 
     if (module.status === 'unlinked') {
+      const preserveLoadOrder =
+        this._config.preserveLoadOrder || this._globalConfig?.preserveLoadOrder;
       // ensure that every import fully evaluates before any siblings are allowed to import.
-      let linkPromiseChain = Promise.resolve();
+      let linkPromiseChain = (Promise<VMModule | void>).resolve();
       // since we might attempt to link the same module in parallel, stick the promise in a weak map so every call to
       // this method can await it
       this._esmModuleLinkingMap.set(
         module,
         module.link((specifier: string, referencingModule: VMModule) => {
-          linkPromiseChain = linkPromiseChain.then(async () => {
-            const mod = await this.resolveModule(
-              specifier,
-              referencingModule.identifier,
-              referencingModule.context
-            );
-            await this.linkAndEvaluateModule(mod);
-            return mod;
-          });
-          return linkPromiseChain;
+          if (preserveLoadOrder) {
+            linkPromiseChain = linkPromiseChain.then(async () => {
+              const mod = await this.resolveModule<VMModule>(
+                specifier,
+                referencingModule.identifier,
+                referencingModule.context,
+              );
+              await this.linkAndEvaluateModule(mod);
+              return mod;
+            });
+            return linkPromiseChain;
+          }
+          return this.resolveModule<VMModule>(
+            specifier,
+            referencingModule.identifier,
+            referencingModule.context,
+          );
         }),
       );
     }

packages/jest-schemas/src/raw-types.ts

@@ -288,6 +288,7 @@ export const RawInitialOptions = Type.Partial(
     outputFile: Type.String(),
     passWithNoTests: Type.Boolean(),
     preset: Type.Union([Type.String(), Type.Null()]),
+    preserveLoadOrder: Type.Boolean(),
     prettierPath: Type.Union([Type.String(), Type.Null()]),
     projects: Type.Array(
       Type.Union([

packages/jest-types/src/Config.ts

@@ -182,6 +182,7 @@ export type DefaultOptions = {
   notifyMode: NotifyMode;
   openHandlesTimeout: number;
   passWithNoTests: boolean;
+  preserveLoadOrder: boolean;
   prettierPath: string;
   resetMocks: boolean;
   resetModules: boolean;
@@ -290,6 +291,7 @@ export type GlobalConfig = {
   openHandlesTimeout: number;
   passWithNoTests: boolean;
   projects: Array<string>;
+  preserveLoadOrder: boolean;
   randomize?: boolean;
   replname?: string;
   reporters?: Array<ReporterConfig>;
@@ -357,6 +359,7 @@ export type ProjectConfig = {
   modulePaths?: Array<string>;
   openHandlesTimeout: number;
   preset?: string;
+  preserveLoadOrder: boolean;
   prettierPath: string;
   reporters: Array<string | ReporterConfig>;
   resetMocks: boolean;
@@ -446,6 +449,7 @@ export type Argv = Arguments<
     onlyFailures: boolean;
     outputFile: string;
     preset: string | null | undefined;
+    preserveLoadOrder: boolean;
     prettierPath: string | null | undefined;
     projects: Array<string>;
     randomize: boolean;

packages/test-utils/src/config.ts

@@ -43,6 +43,7 @@ const DEFAULT_GLOBAL_CONFIG: Config.GlobalConfig = {
   openHandlesTimeout: 1000,
   outputFile: undefined,
   passWithNoTests: false,
+  preserveLoadOrder: false,
   projects: [],
   replname: undefined,
   reporters: [],
@@ -99,6 +100,7 @@ const DEFAULT_PROJECT_CONFIG: Config.ProjectConfig = {
   modulePathIgnorePatterns: [],
   modulePaths: [],
   openHandlesTimeout: 1000,
+  preserveLoadOrder: false,
   prettierPath: 'prettier',
   reporters: [
     'default',