fix: handle more generic null prototype instead of Module

mochajs · Apr 18, 2024 · b4b7066 · b4b7066
1 parent 8ccc02b
commit b4b7066
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Showing 3 changed files with 48 additions and 32 deletions.
diff --git a/lib/utils.js b/lib/utils.js
@@ -138,7 +138,7 @@ function emptyRepresentation(value, typeHint) {
  * canonicalType(global) // 'global'
  * canonicalType(new String('foo') // 'object'
  * canonicalType(async function() {}) // 'asyncfunction'
- * canonicalType(await import(name)) // 'module'
+ * canonicalType(Object.create(null)) // 'null-prototype'
  */
 var canonicalType = (exports.canonicalType = function canonicalType(value) {
   if (value === undefined) {
@@ -147,7 +147,14 @@ var canonicalType = (exports.canonicalType = function canonicalType(value) {
     return 'null';
   } else if (Buffer.isBuffer(value)) {
     return 'buffer';
+  } else if (
+    typeof value === 'object' &&
+    // eslint-disable-next-line no-prototype-builtins
+    !Object.prototype.isPrototypeOf(value)
+  ) {
+    return 'null-prototype';
   }
+
   return Object.prototype.toString
     .call(value)
     .replace(/^\[.+\s(.+?)]$/, '$1')
@@ -213,7 +220,7 @@ exports.type = function type(value) {
 exports.stringify = function (value) {
   var typeHint = canonicalType(value);
 
-  if (!~['object', 'array', 'function', 'module'].indexOf(typeHint)) {
+  if (!~['object', 'array', 'function', 'null-prototype'].indexOf(typeHint)) {
     if (typeHint === 'buffer') {
       var json = Buffer.prototype.toJSON.call(value);
       // Based on the toJSON result
@@ -399,14 +406,12 @@ exports.canonicalize = function canonicalize(value, stack, typeHint) {
         break;
       }
     /* falls through */
-    case 'module':
-      if (value[Symbol.toStringTag] === 'Module') {
-        canonicalizedObj = canonicalizedObj || {};
-        canonicalizedObj['[Symbol.toStringTag]'] = 'Module';
-      }
-    /* falls through */
+    case 'null-prototype':
     case 'object':
       canonicalizedObj = canonicalizedObj || {};
+      if (typeHint === 'null-prototype' && Symbol.toStringTag in value) {
+        canonicalizedObj['[Symbol.toStringTag]'] = value[Symbol.toStringTag];
+      }
       withStack(value, function () {
         Object.keys(value)
           .sort()

diff --git a/test/unit/fixtures/module.mjs b/test/unit/fixtures/module.mjs
diff --git a/test/unit/utils.spec.js b/test/unit/utils.spec.js
@@ -2,8 +2,6 @@
 'use strict';
 
 var utils = require('../../lib/utils');
-const esmUtils = require('../../lib/nodejs/esm-utils');
-const Path = require('node:path');
 var sinon = require('sinon');
 
 describe('lib/utils', function () {
@@ -291,25 +289,42 @@ describe('lib/utils', function () {
         expect(stringify(expected), 'to be', actual);
       });
 
-      it('should represent modules', async function () {
-        if (process.browser) {
-          // Current rollup config cannot `import()`
-          this.skip();
-          return;
-        }
-        const expected = await esmUtils.requireOrImport(
-          Path.join(__dirname, './fixtures/module.mjs')
-        );
-        const actual = [
-          '{',
-          '  "[Symbol.toStringTag]": "Module"',
-          '  "bar": true',
-          '  "default": 123',
-          '  "foo": "abc"',
-          '}'
-        ].join('\n');
+      describe('should represent null prototypes', function () {
+        it('With explicit names', function () {
+          const foo = Object.create(null, {
+            [Symbol.toStringTag]: {value: 'Foo'},
+            bing: {get: () => 'bong', enumerable: true}
+          });
+          const expected = [
+            '{',
+            '  "[Symbol.toStringTag]": "Foo"',
+            '  "bing": "bong"',
+            '}'
+          ].join('\n');
+
+          expect(stringify(foo), 'to be', expected);
+        });
 
-        expect(stringify(expected), 'to be', actual);
+        it('Without names', function () {
+          const unnamed = {
+            bing: 'bong',
+            abc: 123
+          };
+          unnamed.self = unnamed;
+          const expected = [
+            '{',
+            '  "abc": 123',
+            '  "bing": "bong"',
+            '  "self": [Circular]',
+            '}'
+          ].join('\n');
+
+          expect(
+            stringify(Object.setPrototypeOf(unnamed, null)),
+            'to be',
+            expected
+          );
+        });
       });
     });