nodejs
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‎lib/internal/modules/cjs/loader.js‎
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‎lib/internal/modules/cjs/loader.js‎
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+4-4Lines changed: 4 additions & 4 deletions
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‎test/es-module/test-extensionless-esm-type-commonjs.js‎
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‎test/es-module/test-extensionless-esm-type-commonjs.js‎
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‎test/fixtures/es-modules/extensionless-cjs-module/index‎
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‎test/fixtures/es-modules/extensionless-cjs-module/index‎
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‎test/fixtures/es-modules/extensionless-cjs-module/package.json‎
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‎test/fixtures/es-modules/extensionless-cjs-module/package.json‎
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@@ -1952,12 +1952,12 @@ Module._extensions['.js'] = function(module, filename) {
       format = 'typescript';
     }
   } else if (path.extname(filename) === '') {
-    // Extensionless files skip the .js suffix check above. When type is explicit,
-    // follow it so ESM syntax surfaces as SyntaxError for commonjs instead of
-    // silently delegating to ESM.
+    // Extensionless files skip the .js suffix check above. When type is commonjs, follow it so ESM
+    // syntax surfaces as SyntaxError. For type: module, leave format undefined so our syntax
+    // detection handles it (allowing CJS extensionless files in ESM packages).
     pkg = packageJsonReader.getNearestParentPackageJSON(filename);
     const typeFromPjson = pkg?.data?.type;
-    if (typeFromPjson === 'commonjs' || typeFromPjson === 'module') {
+    if (typeFromPjson === 'commonjs') {
       format = typeFromPjson;
     }
   }
 
@@ -17,3 +17,13 @@ spawnSyncAndAssert(process.execPath, [
   stdout: /script STARTED[\s\S]*v\d+\./,
   trim: true,
 });
+
+// CJS extensionless file inside a type: "module" package should work
+// when require()'d. Regression test for https://github.com/nodejs/node/issues/61971
+spawnSyncAndAssert(process.execPath, [
+  '-e', `const m = require(${JSON.stringify(
+    fixtures.path('es-modules', 'extensionless-cjs-module', 'index')
+  )}); if (m.hello !== 'world') throw new Error('expected CJS exports, got: ' + JSON.stringify(m))`,
+], {
+  status: 0,
+});
@@ -0,0 +1 @@
+module.exports = { hello: 'world' };
@@ -0,0 +1,3 @@
+{
+  "type": "module"
+}
Original file line number	Diff line number	Diff line change
`@@ -1952,12 +1952,12 @@ Module._extensions['.js'] = function(module, filename) {`
`1952`	`1952`	`format = 'typescript';`
`1953`	`1953`	`}`
`1954`	`1954`	`} else if (path.extname(filename) === '') {`
`1955`		`- // Extensionless files skip the .js suffix check above. When type is explicit,`
`1956`		`- // follow it so ESM syntax surfaces as SyntaxError for commonjs instead of`
`1957`		`- // silently delegating to ESM.`
	`1955`	`+ // Extensionless files skip the .js suffix check above. When type is commonjs, follow it so ESM`
	`1956`	`+ // syntax surfaces as SyntaxError. For type: module, leave format undefined so our syntax`
	`1957`	`+ // detection handles it (allowing CJS extensionless files in ESM packages).`
`1958`	`1958`	`pkg = packageJsonReader.getNearestParentPackageJSON(filename);`
`1959`	`1959`	`const typeFromPjson = pkg?.data?.type;`
`1960`		`- if (typeFromPjson === 'commonjs' \|\| typeFromPjson === 'module') {`
	`1960`	`+ if (typeFromPjson === 'commonjs') {`
`1961`	`1961`	`format = typeFromPjson;`
`1962`	`1962`	`}`
`1963`	`1963`	`}`