module: add isBuiltIn method

nodejs · Jun 14, 2022 · a66a302 · a66a302
1 parent 5ca2ab1
commit a66a302
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diff --git a/lib/internal/modules/cjs/loader.js b/lib/internal/modules/cjs/loader.js
@@ -191,6 +191,7 @@ for (const { 0: id, 1: mod } of NativeModule.map) {
 ObjectFreeze(builtinModules);
 Module.builtinModules = builtinModules;
 
+
 Module._cache = ObjectCreate(null);
 Module._pathCache = ObjectCreate(null);
 Module._extensions = ObjectCreate(null);
@@ -1293,5 +1294,10 @@ Module.syncBuiltinESMExports = function syncBuiltinESMExports() {
   }
 };
 
+Module.isBuiltIn = function isBuiltIn(moduleName) {
+  moduleName = String(moduleName).replace('node:', '');
+  return Module.builtinModules.includes(moduleName);
+};
+
 // Backwards compatibility
 Module.Module = Module;
diff --git a/test/parallel/test-module-isBuiltIn.js b/test/parallel/test-module-isBuiltIn.js
@@ -0,0 +1,16 @@
+'use strict';
+require('../common');
+const assert = require('assert');
+const { isBuiltIn } = require('module');
+
+// Includes modules in lib/ (even deprecated ones)
+assert(isBuiltIn('http'));
+assert(isBuiltIn('sys'));
+
+// Does not include internal modules
+assert(!isBuiltIn('internal'));
+assert(!isBuiltIn(''));
+assert(!isBuiltIn(undefined));
+
+
+