add _.isSymbol(), fix jashkenas#2501

xcodebuild · Apr 25, 2016 · 48e38ca · 48e38ca
1 parent ce591c8
commit 48e38ca
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Showing 3 changed files with 30 additions and 4 deletions.
diff --git a/test/collections.js b/test/collections.js
@@ -587,6 +587,11 @@
     assert.deepEqual(_.max([0, 2], function(c){ return c * this.x; }, {x: 1}), 2, 'Iterator context');
     assert.deepEqual(_.max([[1], [2, 3], [-1, 4], [5]], 0), [5], 'Lookup falsy iterator');
     assert.deepEqual(_.max([{0: 1}, {0: 2}, {0: -1}, {a: 1}], 0), {0: 2}, 'Lookup falsy iterator');
+
+    if (typeof Symbol !== 'undefined') {
+      assert.equal(_.min([1, 2, 3, Symbol()]), 1, 'Finds correct min in array starting with num and containing a Symbol');
+      assert.equal(_.min([Symbol(), 1, 2, 3]), 1, 'Finds correct min in array starting with Symbol');
+    }
   });
 
   QUnit.test('min', function(assert) {
@@ -630,6 +635,11 @@
     assert.deepEqual(_.min([0, 2], function(c){ return c * this.x; }, {x: -1}), 2, 'Iterator context');
     assert.deepEqual(_.min([[1], [2, 3], [-1, 4], [5]], 0), [-1, 4], 'Lookup falsy iterator');
     assert.deepEqual(_.min([{0: 1}, {0: 2}, {0: -1}, {a: 1}], 0), {0: -1}, 'Lookup falsy iterator');
+
+    if (typeof Symbol !== 'undefined') {
+      assert.equal(_.min([1, 2, 3, Symbol()]), 1, 'Finds correct min in array starting with num and containing a Symbol');
+      assert.equal(_.min([Symbol(), 1, 2, 3]), 1, 'Finds correct min in array starting with Symbol');
+    }
   });
 
   QUnit.test('sortBy', function(assert) {
@@ -678,6 +688,11 @@
 
     list = ['q', 'w', 'e', 'r', 't', 'y'];
     assert.deepEqual(_.sortBy(list), ['e', 'q', 'r', 't', 'w', 'y'], 'uses _.identity if iterator is not specified');
+
+    if (typeof Symbol !== 'undefined') {
+      var sym = Symbol();
+      assert.deepEqual(_.sortBy([8, 6, sym, 4, 23]), [6, 8, sym, 4, 23], 'sortBy should work even containing a Symbol');
+    }
   });
 
   QUnit.test('groupBy', function(assert) {

diff --git a/test/cross-document.js b/test/cross-document.js
@@ -4,7 +4,7 @@
   var _ = typeof require == 'function' ? require('..') : window._;
 
   QUnit.module('Cross Document');
-  /* global iObject, iElement, iArguments, iFunction, iArray, iError, iString, iNumber, iBoolean, iDate, iRegExp, iNaN, iNull, iUndefined, ActiveXObject */
+  /* global iObject, iElement, iArguments, iFunction, iArray, iError, iString, iNumber, iBoolean, iDate, iRegExp, iNaN, iNull, iUndefined, iSymbol, ActiveXObject */
 
   // Setup remote variables for iFrame tests.
   var iframe = document.createElement('iframe');
@@ -110,6 +110,12 @@
     assert.ok(_.isError(iError), 'even from another frame');
   });
 
+  QUnit.test('isSymbol', function(assert) {
+    if (typeof Symbol !== 'undefined') {
+      assert.ok(_.isError(iSymbol), 'even from another frame');
+    }
+  });
+
   if (typeof ActiveXObject != 'undefined') {
     QUnit.test('IE host objects', function(assert) {
       var xml = new ActiveXObject('Msxml2.DOMDocument.3.0');

diff --git a/underscore.js b/underscore.js
@@ -313,7 +313,7 @@
       obj = isArrayLike(obj) ? obj : _.values(obj);
       for (var i = 0, length = obj.length; i < length; i++) {
         value = obj[i];
-        if (value != null && value > result) {
+        if (value != null && !_.isSymbol(value) && value > result) {
           result = value;
         }
       }
@@ -338,7 +338,7 @@
       obj = isArrayLike(obj) ? obj : _.values(obj);
       for (var i = 0, length = obj.length; i < length; i++) {
         value = obj[i];
-        if (value != null && value < result) {
+        if (value != null && !_.isSymbol(value) && value < result) {
           result = value;
         }
       }
@@ -395,7 +395,7 @@
     }).sort(function(left, right) {
       var a = left.criteria;
       var b = right.criteria;
-      if (a !== b) {
+      if (a !== b && !_.isSymbol(a) && !_.isSymbol(b)) {
         if (a > b || a === void 0) return 1;
         if (a < b || b === void 0) return -1;
       }
@@ -1289,6 +1289,11 @@
     return type === 'function' || type === 'object' && !!obj;
   };
 
+  // Is a given value a Symbol?
+  _.isSymbol = function(obj) {
+    return typeof obj === 'symbol';
+  };
+
   // Add some isType methods: isArguments, isFunction, isString, isNumber, isDate, isRegExp, isError, isMap, isWeakMap, isSet, isWeakSet.
   _.each(['Arguments', 'Function', 'String', 'Number', 'Date', 'RegExp', 'Error', 'Symbol', 'Map', 'WeakMap', 'Set', 'WeakSet'], function(name) {
     _['is' + name] = function(obj) {