[Fix] handle core-js Symbol shams

Author: ljharb

.github/workflows/node-iojs.yml

@@ -12,6 +12,7 @@ jobs:
       - uses: ljharb/actions/node/matrix@main
         id: set-matrix
         with:
+          versionsAsRoot: true
           preset: 'iojs'
 
   latest:
@@ -21,7 +22,11 @@ jobs:
 
     strategy:
       fail-fast: false
-      matrix: ${{ fromJson(needs.matrix.outputs.latest) }}
+      matrix:
+        node-version: ${{ fromJson(needs.matrix.outputs.latest) }}
+        command:
+          - 'tests-only'
+          - 'test:corejs'
 
     steps:
       - uses: actions/checkout@v2
@@ -30,7 +35,7 @@ jobs:
         with:
           node-version: ${{ matrix.node-version }}
           skip-ls-check: true
-      - run: npm run tests-only
+      - run: npm run ${{ matrix.command }}
       - uses: codecov/codecov-action@v1
 
   minors:
@@ -42,7 +47,11 @@ jobs:
 
     strategy:
       fail-fast: false
-      matrix: ${{ fromJson(needs.matrix.outputs.minors) }}
+      matrix:
+        node-version: ${{ fromJson(needs.matrix.outputs.minors) }}
+        command:
+          - 'tests-only'
+          - 'test:corejs'
 
     steps:
       - uses: actions/checkout@v2
@@ -51,7 +60,7 @@ jobs:
         with:
           node-version: ${{ matrix.node-version }}
           skip-ls-check: true
-      - run: npm run tests-only
+      - run: npm run ${{ matrix.command }}
       - uses: codecov/codecov-action@v1
 
   node:

.github/workflows/node-zero.yml

@@ -12,6 +12,7 @@ jobs:
       - uses: ljharb/actions/node/matrix@main
         id: set-matrix
         with:
+          versionsAsRoot: true
           preset: '0.x'
 
   stable:
@@ -21,7 +22,11 @@ jobs:
 
     strategy:
       fail-fast: false
-      matrix: ${{ fromJson(needs.matrix.outputs.stable) }}
+      matrix:
+        node-version: ${{ fromJson(needs.matrix.outputs.stable) }}
+        command:
+          - 'tests-only'
+          - 'test:corejs'
 
     steps:
       - uses: actions/checkout@v2
@@ -31,7 +36,7 @@ jobs:
           node-version: ${{ matrix.node-version }}
           cache-node-modules-key: node_modules-${{ github.workflow }}-${{ github.action }}-${{ github.run_id }}
           skip-ls-check: true
-      - run: npm run tests-only
+      - run: npm run ${{ matrix.command }}
       - uses: codecov/codecov-action@v1
 
   unstable:
@@ -43,7 +48,11 @@ jobs:
 
     strategy:
       fail-fast: false
-      matrix: ${{ fromJson(needs.matrix.outputs.unstable) }}
+      matrix:
+        node-version: ${{ fromJson(needs.matrix.outputs.unstable) }}
+        command:
+          - 'tests-only'
+          - 'test:corejs'
 
     steps:
       - uses: actions/checkout@v2
@@ -53,7 +62,7 @@ jobs:
           node-version: ${{ matrix.node-version }}
           cache-node-modules-key: node_modules-${{ github.workflow }}-${{ github.action }}-${{ github.run_id }}
           skip-ls-check: true
-      - run: npm run tests-only
+      - run: npm run ${{ matrix.command }}
       - uses: codecov/codecov-action@v1
 
   node:

.npmignore

@@ -11,3 +11,5 @@ coverage
 .nyc_output
 
 .github/workflows
+
+./test-core-js.js

index.js

@@ -19,6 +19,7 @@ var match = String.prototype.match;
 var bigIntValueOf = typeof BigInt === 'function' ? BigInt.prototype.valueOf : null;
 var gOPS = Object.getOwnPropertySymbols;
 var symToString = typeof Symbol === 'function' && typeof Symbol.iterator === 'symbol' ? Symbol.prototype.toString : null;
+var hasShammedSymbols = typeof Symbol === 'function' && typeof Symbol.iterator === 'object';
 var isEnumerable = Object.prototype.propertyIsEnumerable;
 
 var gPO = (typeof Reflect === 'function' ? Reflect.getPrototypeOf : Object.getPrototypeOf) || (
@@ -31,7 +32,7 @@ var gPO = (typeof Reflect === 'function' ? Reflect.getPrototypeOf : Object.getPr
 
 var inspectCustom = require('./util.inspect').custom;
 var inspectSymbol = inspectCustom && isSymbol(inspectCustom) ? inspectCustom : null;
-var toStringTag = typeof Symbol === 'function' && typeof Symbol.toStringTag === 'symbol' ? Symbol.toStringTag : null;
+var toStringTag = typeof Symbol === 'function' && typeof Symbol.toStringTag !== 'undefined' ? Symbol.toStringTag : null;
 
 module.exports = function inspect_(obj, options, depth, seen) {
     var opts = options || {};
@@ -121,8 +122,8 @@ module.exports = function inspect_(obj, options, depth, seen) {
         return '[Function' + (name ? ': ' + name : ' (anonymous)') + ']' + (keys.length > 0 ? ' { ' + keys.join(', ') + ' }' : '');
     }
     if (isSymbol(obj)) {
-        var symString = symToString.call(obj);
-        return typeof obj === 'object' ? markBoxed(symString) : symString;
+        var symString = hasShammedSymbols ? String(obj).replace(/^(Symbol\(.*\))_[^)]*$/, '$1') : symToString.call(obj);
+        return typeof obj === 'object' && !hasShammedSymbols ? markBoxed(symString) : symString;
     }
     if (isElement(obj)) {
         var s = '<' + String(obj.nodeName).toLowerCase();
@@ -225,6 +226,9 @@ function isBoolean(obj) { return toStr(obj) === '[object Boolean]' && (!toString
 
 // Symbol and BigInt do have Symbol.toStringTag by spec, so that can't be used to eliminate false positives
 function isSymbol(obj) {
+    if (hasShammedSymbols) {
+        return obj && typeof obj === 'object' && obj instanceof Symbol;
+    }
     if (typeof obj === 'symbol') {
         return true;
     }
@@ -432,17 +436,28 @@ function arrObjKeys(obj, inspect) {
             xs[i] = has(obj, i) ? inspect(obj[i], obj) : '';
         }
     }
+    var syms = typeof gOPS === 'function' ? gOPS(obj) : [];
+    var symMap;
+    if (hasShammedSymbols) {
+        symMap = {};
+        for (var k = 0; k < syms.length; k++) {
+            symMap['$' + syms[k]] = syms[k];
+        }
+    }
+
     for (var key in obj) { // eslint-disable-line no-restricted-syntax
         if (!has(obj, key)) { continue; } // eslint-disable-line no-restricted-syntax, no-continue
         if (isArr && String(Number(key)) === key && key < obj.length) { continue; } // eslint-disable-line no-restricted-syntax, no-continue
-        if ((/[^\w$]/).test(key)) {
+        if (hasShammedSymbols && symMap['$' + key] instanceof Symbol) {
+            // this is to prevent shammed Symbols, which are stored as strings, from being included in the string key section
+            continue; // eslint-disable-line no-restricted-syntax, no-continue
+        } else if ((/[^\w$]/).test(key)) {
             xs.push(inspect(key, obj) + ': ' + inspect(obj[key], obj));
         } else {
             xs.push(key + ': ' + inspect(obj[key], obj));
         }
     }
     if (typeof gOPS === 'function') {
-        var syms = gOPS(obj);
         for (var j = 0; j < syms.length; j++) {
             if (isEnumerable.call(obj, syms[j])) {
                 xs.push('[' + inspect(syms[j]) + ']: ' + inspect(obj[syms[j]], obj));

package.json

@@ -21,10 +21,9 @@
     "prepublishOnly": "safe-publish-latest",
     "pretest": "npm run lint",
     "lint": "eslint .",
-    "test": "npm run tests-only",
-    "tests-only": "nyc npm run tests-only:tape",
-    "pretests-only:tape": "node test-core-js",
-    "tests-only:tape": "tape 'test/*.js'",
+    "test": "npm run tests-only && npm run test:corejs",
+    "tests-only": "nyc tape 'test/*.js'",
+    "test:corejs": "nyc tape test-core-js.js 'test/*.js'",
     "posttest": "npx aud --production"
   },
   "testling": {

test/bigint.js

@@ -2,7 +2,7 @@
 
 var inspect = require('../');
 var test = require('tape');
-var hasSymbols = require('has-symbols')();
+var hasSymbols = require('has-symbols/shams')();
 
 test('bigint', { skip: typeof BigInt === 'undefined' }, function (t) {
     t.test('primitives', function (st) {
@@ -30,7 +30,7 @@ test('bigint', { skip: typeof BigInt === 'undefined' }, function (t) {
         st.equal(inspect(Function('return 256n')()), '256n');
     });
 
-    t.test('toStringTag', { skip: !hasSymbols || typeof Symbol.toStringTag !== 'symbol' }, function (st) {
+    t.test('toStringTag', { skip: !hasSymbols || typeof Symbol.toStringTag === 'undefined' }, function (st) {
         st.plan(1);
 
         var faker = {};

test/fakes.js

@@ -2,10 +2,10 @@
 
 var inspect = require('../');
 var test = require('tape');
-var hasSymbols = require('has-symbols')();
+var hasSymbols = require('has-symbols/shams')();
 var forEach = require('for-each');
 
-test('fakes', { skip: !hasSymbols || typeof Symbol.toStringTag !== 'symbol' }, function (t) {
+test('fakes', { skip: !hasSymbols || typeof Symbol.toStringTag === 'undefined' }, function (t) {
     forEach([
         'Array',
         'Boolean',

test/inspect.js

@@ -1,5 +1,5 @@
 var test = require('tape');
-var hasSymbols = require('has-symbols')();
+var hasSymbols = require('has-symbols/shams')();
 var utilInspect = require('../util.inspect');
 var repeat = require('string.prototype.repeat');
 
@@ -43,8 +43,22 @@ test('symbols', { skip: !hasSymbols }, function (t) {
         value: 4
     });
 
-    t.equal(inspect(obj), '{ a: 1, [Symbol(test)]: 2, [Symbol(Symbol.iterator)]: 3 }', 'object with symbols');
-    t.equal(inspect([obj, []]), '[ { a: 1, [Symbol(test)]: 2, [Symbol(Symbol.iterator)]: 3 }, [] ]', 'object with symbols');
+    if (typeof Symbol.iterator === 'symbol') {
+        t.equal(inspect(obj), '{ a: 1, [Symbol(test)]: 2, [Symbol(Symbol.iterator)]: 3 }', 'object with symbols');
+        t.equal(inspect([obj, []]), '[ { a: 1, [Symbol(test)]: 2, [Symbol(Symbol.iterator)]: 3 }, [] ]', 'object with symbols in array');
+    } else {
+        // symbol sham key ordering is unreliable
+        t.match(
+            inspect(obj),
+            /^(?:{ a: 1, \[Symbol\(test\)\]: 2, \[Symbol\(Symbol.iterator\)\]: 3 }|{ a: 1, \[Symbol\(Symbol.iterator\)\]: 3, \[Symbol\(test\)\]: 2 })$/,
+            'object with symbols (nondeterministic symbol sham key ordering)'
+        );
+        t.match(
+            inspect([obj, []]),
+            /^\[ (?:{ a: 1, \[Symbol\(test\)\]: 2, \[Symbol\(Symbol.iterator\)\]: 3 }|{ a: 1, \[Symbol\(Symbol.iterator\)\]: 3, \[Symbol\(test\)\]: 2 }), \[\] \]$/,
+            'object with symbols in array (nondeterministic symbol sham key ordering)'
+        );
+    }
 });
 
 test('maxStringLength', function (t) {

test/toStringTag.js

@@ -1,11 +1,11 @@
 'use strict';
 
 var test = require('tape');
-var hasSymbols = require('has-symbols')();
+var hasSymbols = require('has-symbols/shams')();
 
-var inspect = require('..');
+var inspect = require('../');
 
-test('Symbol.toStringTag', { skip: !hasSymbols || typeof Symbol.toStringTag !== 'symbol' }, function (t) {
+test('Symbol.toStringTag', { skip: !hasSymbols || typeof Symbol.toStringTag === 'undefined' }, function (t) {
     t.plan(4);
 
     var obj = { a: 1 };

test/values.js

@@ -2,7 +2,7 @@
 
 var inspect = require('../');
 var test = require('tape');
-var hasSymbols = require('has-symbols')();
+var hasSymbols = require('has-symbols/shams')();
 
 test('values', function (t) {
     t.plan(1);
@@ -68,12 +68,15 @@ test('seen seen seen', function (t) {
     );
 });
 
-test('symbols', { skip: typeof Symbol !== 'function' }, function (t) {
+test('symbols', { skip: !hasSymbols }, function (t) {
     var sym = Symbol('foo');
     t.equal(inspect(sym), 'Symbol(foo)', 'Symbol("foo") should be "Symbol(foo)"');
-    t.equal(inspect(Object(sym)), 'Object(Symbol(foo))', 'Object(Symbol("foo")) should be "Object(Symbol(foo))"');
+    if (typeof sym === 'symbol') {
+        // Symbol shams are incapable of differentiating boxed from unboxed symbols
+        t.equal(inspect(Object(sym)), 'Object(Symbol(foo))', 'Object(Symbol("foo")) should be "Object(Symbol(foo))"');
+    }
 
-    t.test('toStringTag', { skip: !hasSymbols || typeof Symbol.toStringTag !== 'symbol' }, function (st) {
+    t.test('toStringTag', { skip: !hasSymbols || typeof Symbol.toStringTag === 'undefined' }, function (st) {
         st.plan(1);
 
         var faker = {};