fix: support canonical module (#5040)

* fix: handle canonicalizing Module * fix: add tests for canonicalizing a module * fix: skip module serialization on browser * fix: handle more generic null prototype instead of Module * fix: simplify null prototype check
mochajs · Jul 20, 2024 · 579e047 · 579e047
1 parent 6d24689
commit 579e047
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Showing 2 changed files with 47 additions and 2 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 +147,10 @@ var canonicalType = (exports.canonicalType = function canonicalType(value) {
     return 'null';
   } else if (Buffer.isBuffer(value)) {
     return 'buffer';
+  } else if (Object.getPrototypeOf(value) === null) {
+    return 'null-prototype';
   }
+
   return Object.prototype.toString
     .call(value)
     .replace(/^\[.+\s(.+?)]$/, '$1')
@@ -213,7 +216,7 @@ exports.type = function type(value) {
 exports.stringify = function (value) {
   var typeHint = canonicalType(value);
 
-  if (!~['object', 'array', 'function'].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
@@ -399,8 +402,12 @@ exports.canonicalize = function canonicalize(value, stack, typeHint) {
         break;
       }
     /* 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/utils.spec.js b/test/unit/utils.spec.js
@@ -288,6 +288,44 @@ describe('lib/utils', function () {
         ].join('\n');
         expect(stringify(expected), 'to be', actual);
       });
+
+      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);
+        });
+
+        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
+          );
+        });
+      });
     });
 
     it('should canonicalize the object', function () {