fix(rspack): lazy-load @rspack/core in create-compiler to avoid eager ESM resolution (#36476)

Co-authored-by: Claude Sonnet 5 <noreply@anthropic.com>
Co-authored-by: Claude <noreply@anthropic.com>
Co-authored-by: nx-cloud[bot] <71083854+nx-cloud[bot]@users.noreply.github.com>
Co-authored-by: Jason Jean <jasonjean1993@gmail.com>

Author: 4 people

packages/rspack/src/plugins/utils/apply-base-config.ts

@@ -10,6 +10,7 @@ import type {
 } from '@rspack/core';
 import { getRootTsConfigPath } from '@nx/js';
 import { getRspackCoreMajorVersion } from '../../utils/version-utils';
+import { loadRspackCore } from '../../utils/load-rspack-core';
 
 import { StatsJsonPlugin } from './plugins/stats-json-plugin';
 import { GeneratePackageJsonPlugin } from './plugins/generate-package-json-plugin';
@@ -60,10 +61,8 @@ export function applyBaseConfig(
   options.outputHashing ??= 'all';
 
   // Lazy-require avoids loading @rspack/core (pure ESM in v2) at module
-  // parse time, so Jest can still load this file.
-  const rspackCore: typeof import('@rspack/core') = compiler
-    ? (compiler.rspack as unknown as typeof import('@rspack/core'))
-    : require('@rspack/core');
+  // parse time, so Jest can still load this file. See load-rspack-core.ts.
+  const rspackCore = loadRspackCore(compiler);
 
   applyNxIndependentConfig(options, config, rspackCore);
 

packages/rspack/src/plugins/utils/apply-web-config.ts

@@ -17,6 +17,7 @@ import {
 } from './loaders/stylesheet-loaders';
 import { NormalizedNxAppRspackPluginOptions } from './models';
 import { normalizeExtraEntryPoints } from './normalize-entry';
+import { loadRspackCore } from '../../utils/load-rspack-core';
 
 export function applyWebConfig(
   options: NormalizedNxAppRspackPluginOptions,
@@ -37,9 +38,8 @@ export function applyWebConfig(
   // Prefer compiler.rspack when available; otherwise lazy-require
   // @rspack/core (works on Node 22.12+ via require(esm), and keeps the
   // file Jest-loadable since the require is inside the function body).
-  const rspackCore: typeof import('@rspack/core') = compiler
-    ? (compiler.rspack as unknown as typeof import('@rspack/core'))
-    : require('@rspack/core');
+  // See load-rspack-core.ts.
+  const rspackCore = loadRspackCore(compiler);
   const {
     CssExtractRspackPlugin,
     DefinePlugin,

packages/rspack/src/utils/create-compiler.ts

@@ -1,13 +1,9 @@
 import { ExecutorContext } from '@nx/devkit';
-import {
-  rspack,
-  type Compiler,
-  type Configuration,
-  type MultiCompiler,
-} from '@rspack/core';
+import type { Compiler, Configuration, MultiCompiler } from '@rspack/core';
 
 import { NormalizedRspackExecutorSchema } from '../executors/rspack/schema';
 import { getRspackConfigs } from '../executors/rspack/lib/config';
+import { loadRspackCore } from './load-rspack-core';
 
 export async function createCompiler(
   options: NormalizedRspackExecutorSchema & {
@@ -21,6 +17,8 @@ export async function createCompiler(
     validateConfig(config);
   }
 
+  // Lazy-loaded to avoid resolving @rspack/core (pure ESM) before a build runs; see load-rspack-core.ts.
+  const { rspack } = loadRspackCore();
   return rspack(config);
 }
 

packages/rspack/src/utils/load-rspack-core.ts

@@ -0,0 +1,11 @@
+import type { Compiler } from '@rspack/core';
+
+// @rspack/core v2 is pure ESM; lazy-require avoids resolving it before a Compiler exists.
+export function loadRspackCore(
+  compiler?: Pick<Compiler, 'rspack'>
+): typeof import('@rspack/core') {
+  // Reuse the compiler's already-resolved module to avoid ending up with a second, possibly different copy.
+  return compiler
+    ? (compiler.rspack as unknown as typeof import('@rspack/core'))
+    : require('@rspack/core');
+}