fix: rename __webpack_require__ in arrow function scopes (#20661)

hai-x · web-flow · commit a836e064c80d · 2026-03-17T22:52:22.000+03:00
diff --git a/.changeset/late-dingos-wonder.md b/.changeset/late-dingos-wonder.md
@@ -0,0 +1,5 @@
+---
+"webpack": patch
+---
+
+Fix `CompatibilityPlugin` to correctly rename `__webpack_require__` when it appears as an arrow function parameter (e.g. `(__webpack_module, __webpack_exports, __webpack_require__) => { ... }`).
diff --git a/lib/CompatibilityPlugin.js b/lib/CompatibilityPlugin.js
@@ -147,7 +147,7 @@ class CompatibilityPlugin {
 									range: /** @type {Range} */ (pattern.range)
 								}
 							});
-							if (!parser.scope.topLevelScope) {
+							if (parser.scope.topLevelScope !== true) {
 								return true;
 							}
 						});
diff --git a/test/configCases/module/consume-webpack-runtime/index.js b/test/configCases/module/consume-webpack-runtime/index.js
@@ -3,6 +3,7 @@ import defaultUse from './runtime-export-default'
 import { __webpack_require__ as namedDeclUse } from './runtime-export-decl'
 import { __webpack_require__ as objectRequire, __webpack_exports__ as objectExport } from './runtime-single-require-and-export'
 import defaultUseNested from './runtime-multiple-nested'
+import "./runtime-arrow-scope";
 
 it("should compile and run", () => {
 	expect(namedUse()).toBe(42);
@@ -17,7 +18,7 @@ it("should compile and run", () => {
 	{
 		const content = fs.readFileSync(path.resolve(__dirname, './bundle0.js'), 'utf-8');
 		const NESTED_RE = /__nested_webpack_require_([^_]+)__/g;
-		expect(content.match(NESTED_RE).length).toBe(13);
+		expect(content.match(NESTED_RE).length).toBe(17);
 	}
 
 	{
@@ -29,7 +30,7 @@ it("should compile and run", () => {
 	{
 		const content = fs.readFileSync(path.resolve(__dirname, './bundle1.js'), 'utf-8');
 		const NESTED_RE = /__nested_webpack_require_([^_]+)__/g;
-		expect(content.match(NESTED_RE).length).toBe(15);
+		expect(content.match(NESTED_RE).length).toBe(19);
 	}
 
 	{
@@ -41,7 +42,7 @@ it("should compile and run", () => {
 	{
 		const content = fs.readFileSync(path.resolve(__dirname, './bundle2.js'), 'utf-8');
 		const NESTED_RE = /__nested_webpack_require_([^_]+)__/g;
-		expect(content.match(NESTED_RE).length).toBe(13);
+		expect(content.match(NESTED_RE).length).toBe(17);
 	}
 
 	{
@@ -53,7 +54,7 @@ it("should compile and run", () => {
 	{
 		const content = fs.readFileSync(path.resolve(__dirname, './bundle3.js'), 'utf-8');
 		const NESTED_RE = /__nested_webpack_require_([^_]+)__/g;
-		expect(content.match(NESTED_RE).length).toBe(15);
+		expect(content.match(NESTED_RE).length).toBe(19);
 	}
 
 	{
diff --git a/test/configCases/module/consume-webpack-runtime/runtime-arrow-scope.js b/test/configCases/module/consume-webpack-runtime/runtime-arrow-scope.js
@@ -0,0 +1,16 @@
+function __webpack_require__() {
+	throw new Error("Should be unreached");
+}
+
+const modules = [
+	// `__webpack_require__` as arrow fn params should be replaced
+	((__webpack_require__) => {
+		require("./shared");
+		try{
+			__webpack_require__()
+		}	catch {}
+
+	})
+];
+
+modules[0](__webpack_require__);
diff --git a/test/configCases/module/consume-webpack-runtime/shared.js b/test/configCases/module/consume-webpack-runtime/shared.js

-Original file line number
+Diff line change
@@ @@ -0,0 +1,5 @@ @@
 +---
 +"webpack": patch
 +---
++
 +Fix `CompatibilityPlugin` to correctly rename `__webpack_require__` when it appears as an arrow function parameter (e.g. `(__webpack_module, __webpack_exports, __webpack_require__) => { ... }`).
Original file line number	Diff line number	Diff line change
`@@ -147,7 +147,7 @@ class CompatibilityPlugin {`
`147`	`147`	`range: /** @type {Range} */ (pattern.range)`
`148`	`148`	`}`
`149`	`149`	`});`
`150`		`- if (!parser.scope.topLevelScope) {`
	`150`	`+ if (parser.scope.topLevelScope !== true) {`
`151`	`151`	`return true;`
`152`	`152`	`}`
`153`	`153`	`});`
Original file line number	Diff line number	Diff line change
`@@ -3,6 +3,7 @@ import defaultUse from './runtime-export-default'`
`3`	`3`	`import { __webpack_require__ as namedDeclUse } from './runtime-export-decl'`
`4`	`4`	`import { __webpack_require__ as objectRequire, __webpack_exports__ as objectExport } from './runtime-single-require-and-export'`
`5`	`5`	`import defaultUseNested from './runtime-multiple-nested'`
	`6`	`+import "./runtime-arrow-scope";`
`6`	`7`
`7`	`8`	`it("should compile and run", () => {`
`8`	`9`	`expect(namedUse()).toBe(42);`
`@@ -17,7 +18,7 @@ it("should compile and run", () => {`
`17`	`18`	`{`
`18`	`19`	`const content = fs.readFileSync(path.resolve(__dirname, './bundle0.js'), 'utf-8');`
`19`	`20`	`const NESTED_RE = /__nested_webpack_require_([^_]+)__/g;`
`20`		`- expect(content.match(NESTED_RE).length).toBe(13);`
	`21`	`+ expect(content.match(NESTED_RE).length).toBe(17);`
`21`	`22`	`}`
`22`	`23`
`23`	`24`	`{`
`@@ -29,7 +30,7 @@ it("should compile and run", () => {`
`29`	`30`	`{`
`30`	`31`	`const content = fs.readFileSync(path.resolve(__dirname, './bundle1.js'), 'utf-8');`
`31`	`32`	`const NESTED_RE = /__nested_webpack_require_([^_]+)__/g;`
`32`		`- expect(content.match(NESTED_RE).length).toBe(15);`
	`33`	`+ expect(content.match(NESTED_RE).length).toBe(19);`
`33`	`34`	`}`
`34`	`35`
`35`	`36`	`{`
`@@ -41,7 +42,7 @@ it("should compile and run", () => {`
`41`	`42`	`{`
`42`	`43`	`const content = fs.readFileSync(path.resolve(__dirname, './bundle2.js'), 'utf-8');`
`43`	`44`	`const NESTED_RE = /__nested_webpack_require_([^_]+)__/g;`
`44`		`- expect(content.match(NESTED_RE).length).toBe(13);`
	`45`	`+ expect(content.match(NESTED_RE).length).toBe(17);`
`45`	`46`	`}`
`46`	`47`
`47`	`48`	`{`
`@@ -53,7 +54,7 @@ it("should compile and run", () => {`
`53`	`54`	`{`
`54`	`55`	`const content = fs.readFileSync(path.resolve(__dirname, './bundle3.js'), 'utf-8');`
`55`	`56`	`const NESTED_RE = /__nested_webpack_require_([^_]+)__/g;`
`56`		`- expect(content.match(NESTED_RE).length).toBe(15);`
	`57`	`+ expect(content.match(NESTED_RE).length).toBe(19);`
`57`	`58`	`}`
`58`	`59`
`59`	`60`	`{`