es6-shim - npm Package Compare versions

Comparing version 0.5.2 to 0.5.3

CHANGELOG.md

@@ -0,1 +1,4 @@
+# es6-shim 0.5.3 (September 2, 2012)
+* Made `String#startsWith`, `String#endsWith` fully conform spec.
+
 # es6-shim 0.5.2 (June 17, 2012)
@@ -2,0 +5,0 @@ * Removed `String#toArray` and `Object.isObject` as per spec updates.

es6-shim.js

@@ -1,4 +0,8 @@
-({define: (typeof define === 'function')
-    ? define  // RequireJS
-    : function(definition) {definition();} // CommonJS and <script>
+// ES6-shim 0.5.3 (c) 2012 Paul Miller (paulmillr.com)
+// ES6-shim may be freely distributed under the MIT license.
+// For more details and documentation:
+// https://github.com/paulmillr/es6-shim/
+({define: (typeof define === 'function') ?
+  define : // RequireJS
+  function(definition) {definition();} // CommonJS and <script>
 }).define(function() {
@@ -35,17 +39,92 @@ 'use strict';
   defineProperties(String.prototype, {
+    // Fast repeat, uses the `Exponentiation by squaring` algorithm.
     repeat: function(times) {
-      return new Array(times + 1).join(this);
+      if (times < 1) return '';
+      if (times % 2) return this.repeat(times - 1) + this;
+      var half = this.repeat(times / 2);
+      return half + half;
     },
 
-    startsWith: function(substring) {
-      return this.lastIndexOf(substring, 0) === 0;
+    startsWith: function(searchString) {
+      var position = arguments[1];
+
+      // Let searchStr be ToString(searchString).
+      var searchStr = searchString.toString();
+
+      // ReturnIfAbrupt(searchStr).
+
+      // Let S be the result of calling ToString,
+      // giving it the this value as its argument.
+      var s = this.toString();
+
+      // ReturnIfAbrupt(S).
+
+      // Let pos be ToInteger(position).
+      // (If position is undefined, this step produces the value 0).
+      var pos = (position === undefined) ? 0 : Number.toInteger(position);
+      // ReturnIfAbrupt(pos).
+
+      // Let len be the number of elements in S.
+      var len = s.length;
+
+      // Let start be min(max(pos, 0), len).
+      var start = Math.min(Math.max(pos, 0), len);
+
+      // Let searchLength be the number of elements in searchString.
+      var searchLength = searchString.length;
+
+      // If searchLength+start is greater than len, return false.
+      if ((searchLength + start) > len) return false;
+
+      // If the searchLength sequence of elements of S starting at
+      // start is the same as the full element sequence of searchString,
+      // return true.
+      var index = ''.indexOf.call(s, searchString, start);
+      return index === start;
     },
 
-    endsWith: function(substring) {
-      var startFrom = this.length - String(substring).length;
-      return startFrom >= 0 && this.indexOf(substring, startFrom) === startFrom;
+    endsWith: function(searchString) {
+      var endPosition = arguments[1];
+
+      // ReturnIfAbrupt(CheckObjectCoercible(this value)).
+      // Let S be the result of calling ToString, giving it the this value as its argument.
+      // ReturnIfAbrupt(S).
+      var s = this.toString();
+
+      // Let searchStr be ToString(searchString).
+      // ReturnIfAbrupt(searchStr).
+      var searchStr = searchString.toString();
+
+      // Let len be the number of elements in S.
+      var len = s.length;
+
+      // If endPosition is undefined, let pos be len, else let pos be ToInteger(endPosition).
+      // ReturnIfAbrupt(pos).
+      var pos = (endPosition === undefined) ?
+        len :
+        Number.toInteger(endPosition);
+
+      // Let end be min(max(pos, 0), len).
+      var end = Math.min(Math.max(pos, 0), len);
+
+      // Let searchLength be the number of elements in searchString.
+      var searchLength = searchString.length;
+
+      // Let start be end - searchLength.
+      var start = end - searchLength;
+
+      // If start is less than 0, return false.
+      if (start < 0) return false;
+
+      // If the searchLength sequence of elements of S starting at start is the same as the full element sequence of searchString, return true.
+      // Otherwise, return false.
+      var index = ''.indexOf.call(s, searchString, start);
+      return index === start;
     },
 
-    contains: function(substring) {
-      return this.indexOf(substring) !== -1;
+    contains: function(searchString) {
+      var position = arguments[1];
+
+      // Somehow this trick makes method 100% compat with the spec.
+      return ''.indexOf.call(this, searchString, position) !== -1;
     }
@@ -56,3 +135,3 @@ });
     from: function(iterable) {
-      var object = Object(iterable);
+      var object = new Object(iterable);
       var array = [];
@@ -132,12 +211,14 @@
 
-    getPropertyNames: function(subject, name) {
+    getPropertyNames: function(subject) {
       var result = Object.getOwnPropertyNames(subject);
       var proto = Object.getPrototypeOf(subject);
-      var property;
+
+      var addProperty = function(property) {
+        if (result.indexOf(property) === -1) {
+          result.push(property);
+        }
+      };
+
       while (proto !== null) {
-        Object.getOwnPropertyNames(proto).forEach(function(property) {
-          if (result.indexOf(property) === -1) {
-            result.push(property);
-          }
-        });
+        Object.getOwnPropertyNames(proto).forEach(addProperty);
         proto = Object.getPrototypeOf(proto);
@@ -150,3 +231,3 @@ }
       if (x === y) {
-        // 0 === -0, but they are not identical
+        // 0 === -0, but they are not identical.
         if (x === 0) {
@@ -163,11 +244,11 @@ return 1 / x === 1 / y;
       // isNaN is broken: it converts its argument to number, so
-      // isNaN("foo") => true
+      // isNaN('foo') => true
       return x !== x && y !== y;
     },
-    
+
     isnt: function(x, y) {
       return !Object.is(x, y);
     }
-  });  
-  
+  });
+
   defineProperties(Math, {
@@ -177,7 +258,7 @@ acosh: function(value) {
     },
-    
+
     asinh: function(value) {
       return Math.log(value + Math.sqrt(value * value + 1));
     },
-    
+
     atanh: function(value) {
@@ -192,3 +273,3 @@ return 0.5 * Math.log((1 + value) / (1 - value));
     },
-    
+
     expm1: function(value) {
@@ -202,3 +283,3 @@ var result = 0;
     },
-    
+
     hypot: function(x, y) {
@@ -211,7 +292,7 @@ return Math.sqrt(x * x + y * y) || 0;
     },
-    
+
     log10: function(value) {
       return Math.log(value) * (1 / Math.LN10);
     },
-    
+
     log1p: function(value) {
@@ -240,11 +321,11 @@ var result = 0;
     },
-    
+
     sinh: function(value) {
       return (Math.exp(value) - Math.exp(-value)) / 2;
     },
-    
+
     tanh: function(value) {
       return (Math.exp(value) - Math.exp(-value)) / (Math.exp(value) + Math.exp(-value));
     },
-    
+
     trunc: function(value) {
@@ -265,3 +346,3 @@ return ~~value;
       function Map() {
-        if (!(this instanceof Map)) return new Map;
+        if (!(this instanceof Map)) return new Map();
         defineProperty(this, 'keys', []);
@@ -306,4 +387,4 @@ defineProperty(this, 'values', []);
       function Set() {
-        if (!(this instanceof Set)) return new Set;
-        defineProperty(this, 'map', Map());
+        if (!(this instanceof Set)) return new Set();
+        defineProperty(this, 'map', new Map());
       }
@@ -310,0 +391,0 @@

package.json

@@ -5,3 +5,3 @@ {
   "description": "ECMAScript 6 (Harmony) compatibility shims for legacy JavaScript engines",
-  "version": "0.5.2",
+  "version": "0.5.3",
   "homepage": "https://github.com/paulmillr/es6-shim/",
@@ -14,3 +14,3 @@ "repository": {
   "scripts": {
-    "test": "./node_modules/mocha/bin/mocha --reporter spec --require 'test/test_helpers.js'"
+    "test": "mocha --require 'test/test_helpers.js'"
   },
@@ -17,0 +17,0 @@ "engines": {

test/array.js

@@ -19,3 +19,3 @@ describe('Array', function() {
   });
-  
+
   describe('Array.of()', function() {
@@ -22,0 +22,0 @@ it('should create correct array from arguments', function() {

test/collections.js

@@ -12,3 +12,3 @@ // Big thanks to V8 folks for test ideas.
   };
-  
+
   var expectNotEnumerable = function(object) {
@@ -28,3 +28,3 @@ expect(Object.keys(object).length).to.equal(0);
     });
-    
+
     afterEach(function() {
@@ -46,3 +46,3 @@ map = null;
 
-    it('should map values correctly', function() {      
+    it('should map values correctly', function() {
       range(1, 20).forEach(function(number) {
@@ -53,3 +53,3 @@ testMapping(number, new Object);
       });
-      
+
       [+0, -0, Infinity, -Infinity, true, false, null, undefined].forEach(function(key) {
@@ -59,3 +59,3 @@ testMapping(key, new Object);
     });
-    
+
     it('should has correct querying behavior', function() {
@@ -70,7 +70,7 @@ var key = new Object;
     });
-    
+
     it('should allow to be initialized directly', function() {
       expect(Map()).to.be.an.instanceof(Map);
     });
-    
+
     it('should allow NaN values as keys', function() {
@@ -85,3 +85,3 @@ expect(map.has(NaN)).to.be.false;
     });
-    
+
     it('should not have [[Enumerable]] props', function() {
@@ -92,3 +92,3 @@ expectNotEnumerable(Map);
     });
-    
+
     it('should allow common ecmascript idioms', function() {
@@ -101,3 +101,3 @@ expect(map).to.be.an.instanceof(Map);
     });
-    
+
     it('should has unique constructor', function() {
@@ -114,3 +114,3 @@ expect(Map.prototype).to.not.equal(Object.prototype);
     });
-    
+
     afterEach(function() {
@@ -123,3 +123,3 @@ set = null;
     });
-    
+
     it('should has valid getter and setter calls', function() {
@@ -132,3 +132,3 @@ ['add', 'has', 'delete'].forEach(function(method) {
     });
-    
+
     it('should work as expected', function() {
@@ -142,3 +142,3 @@ var testSet = function(key) {
       };
-      
+
       range(1, 20).forEach(function(number) {
@@ -150,10 +150,10 @@ testSet(new Object);
       });
-      
+
       [+0, -0, Infinity, -Infinity, true, false, null, undefined].forEach(testSet);
     });
-    
+
     it('should allow to be initialized directly', function() {
       expect(Set()).to.be.an.instanceof(Set);
     });
-    
+
     it('should allow NaN values as keys', function() {
@@ -168,3 +168,3 @@ expect(set.has(NaN)).to.be.false;
     });
-    
+
     it('should not have [[Enumerable]] props', function() {
@@ -182,12 +182,12 @@ expectNotEnumerable(Set);
     });
-    
+
     it('should has unique constructor', function() {
       expect(Set.prototype).to.not.equal(Object.prototype);
     });
-    
+
     it('should throw proper errors when user invokes methods with wrong types of receiver',
       function() {
-      
+
     });
   });
 });

test/number.js

@@ -17,3 +17,3 @@ describe('Number', function() {
     });
-    
+
     it('should has epsilon', function() {
@@ -40,4 +40,30 @@ expect(Number.EPSILON).to.equal(2.220446049250313e-16);
       infinities.map(Number.isFinite).forEach(expectToNotBeOk);
+      expect(Number.isFinite(Infinity)).to.not.be.ok
+      expect(Number.isFinite(-Infinity)).to.not.be.ok;
+      expect(Number.isFinite(NaN)).to.not.be.ok;
+      expect(Number.isFinite(4)).to.be.ok;
+      expect(Number.isFinite(4.5)).to.be.ok;
+      expect(Number.isFinite('hi')).to.not.be.ok;
+      expect(Number.isFinite('1.3')).to.not.be.ok;
+      expect(Number.isFinite('51')).to.not.be.ok;
+      expect(Number.isFinite(0)).to.be.ok;
+      expect(Number.isFinite(-0)).to.be.ok;
+      expect(Number.isFinite({
+        valueOf: function() { return 3; }
+      })).to.not.be.ok;
+      expect(Number.isFinite({
+        valueOf: function() { return 0/0; }
+      })).to.not.be.ok;
+      expect(Number.isFinite({
+        valueOf: function() { throw 17; }
+      })).to.not.be.ok;
+      expect(Number.isFinite({
+        toString: function() { throw 17; }
+      })).to.not.be.ok;
+      expect(Number.isFinite({
+        valueOf: function() { throw 17; },
+        toString: function() { throw 42; }
+      })).to.not.be.ok;
     });
-    
+
     it('should not be confused by type coercion', function() {
@@ -51,9 +77,31 @@ nonNumbers.map(Number.isFinite).forEach(expectToNotBeOk);
       integers.map(Number.isInteger).forEach(expectToBeOk);
+      expect(Number.isInteger(4)).to.be.ok;
+      expect(Number.isInteger(4.)).to.be.ok;
+      expect(Number.isInteger(4.2)).to.not.be.ok;
+      expect(Number.isInteger(0.)).to.be.ok;
+      expect(Number.isInteger(-0.)).to.be.ok;
+      expect(Number.isInteger(Infinity)).to.not.be.ok;
+      expect(Number.isInteger(-Infinity)).to.not.be.ok;
+      expect(Number.isInteger(NaN)).to.not.be.ok;
+      expect(Number.isInteger(true)).to.not.be.ok;
+      expect(Number.isInteger(false)).to.not.be.ok;
+      expect(Number.isInteger('str')).to.not.be.ok;
+      expect(Number.isInteger({})).to.not.be.ok;
+      expect(Number.isInteger({
+        valueOf: function() { return 3; }
+      })).to.not.be.ok;
+      expect(Number.isInteger({
+        valueOf: function() { return 0/0; }
+      })).to.not.be.ok;
+      expect(Number.isInteger({
+        valueOf: function() { throw 17; }
+      })).to.not.be.ok;
+      expect(Number.isInteger({
+        toString: function() { throw 17; }
+      })).to.not.be.ok;
+      expect(Number.isInteger({
+        valueOf: function() { throw 17; },
+        toString: function() { throw 42; }
+      })).to.not.be.ok;
     });
-
-    it('should not be confused by type coercion', function() {
-      nonIntegers.concat(
-        infinities, nonNumbers
-      ).map(Number.isInteger).forEach(expectToNotBeOk);
-    });
   });
@@ -63,8 +111,22 @@
     it('should be truthy only on NaN', function() {
-      expect(Number.isNaN(NaN)).to.be.ok;
       integers.concat(nonIntegers).map(Number.isNaN).forEach(expectToNotBeOk);
-    });
-
-    it('should not be confused by type coercion', function() {
       nonNumbers.map(Number.isNaN).forEach(expectToNotBeOk);
+      expect(Number.isNaN(NaN)).to.be.ok;
+      expect(Number.isNaN(0/0)).to.be.ok;
+      expect(Number.isNaN(Number('NaN'))).to.be.ok;
+      expect(Number.isNaN(4)).to.not.be.ok;
+      expect(Number.isNaN(4.5)).to.not.be.ok;
+      expect(Number.isNaN('hi')).to.not.be.ok;
+      expect(Number.isNaN('1.3')).to.not.be.ok;
+      expect(Number.isNaN('51')).to.not.be.ok;
+      expect(Number.isNaN(0)).to.not.be.ok;
+      expect(Number.isNaN(-0)).to.not.be.ok;
+      expect(Number.isNaN({valueOf: function() { return 3; }})).to.not.be.ok;
+      expect(Number.isNaN({valueOf: function() { return 0/0; }})).to.not.be.ok;
+      expect(Number.isNaN({valueOf: function() { throw 17; } })).to.not.be.ok;
+      expect(Number.isNaN({toString: function() { throw 17; } })).to.not.be.ok;
+      expect(Number.isNaN({
+        valueOf: function() { throw 17; },
+        toString: function() { throw 42; }
+      })).to.not.be.ok;
     });
@@ -75,9 +137,30 @@ });
     it('should convert things to integer value', function() {
-      integers.concat(infinities).forEach(function(item) {
-        expect(Number.toInteger(item)).to.equal(item);
-      });
-      [[1.5, 1], [-1.5, -1], [1/3, 0], [NaN, 0], ['str', 0]
-        ].forEach(function(item) {
-        expect(Number.toInteger(item[0])).to.equal(item[1]);
-      });
+      expect(Number.toInteger(4)).to.equal(4);
+      expect(Number.toInteger(4.)).to.equal(4);
+      expect(Number.toInteger(4.3)).to.equal(4);
+      expect(Number.toInteger(-4)).to.equal(-4);
+      expect(Number.toInteger(-4.)).to.equal(-4);
+      expect(Number.toInteger(-4.3)).to.equal(-4);
+      expect(Number.toInteger(0.)).to.equal(0.);
+      expect(Number.toInteger(-0.)).to.equal(-0.);
+      expect(Number.toInteger(Infinity)).to.equal(Infinity);
+      expect(Number.toInteger(-Infinity)).to.equal(-Infinity);
+      expect(Number.toInteger(NaN)).to.equal(0);
+      expect(Number.toInteger(null)).to.equal(0);
+      expect(Number.toInteger(undefined)).to.equal(0);
+      expect(Number.toInteger(true)).to.equal(1);
+      expect(Number.toInteger(false)).to.equal(0);
+      expect(Number.toInteger({
+        valueOf: function() { return 4; }
+      })).to.equal(4);
+      expect(Number.toInteger({
+        valueOf: function() { return 4.3; }
+      })).to.equal(4);
+      expect(Number.toInteger({
+        valueOf: function() { return '4'; }
+      })).to.equal(4);
+      expect(Number.toInteger({
+        valueOf: function() { return {};}
+      })).to.equal(0);
+      expect(Number.toInteger()).to.equal(0);
     });
@@ -84,0 +167,0 @@ });

test/object.js

@@ -47,3 +47,3 @@ describe('Object', function() {
   });
-  
+
   describe('Object.getPropertyDescriptor()', function() {
@@ -50,0 +50,0 @@ it('should produce an array of properties including inherited ones',

test/string.js

@@ -11,5 +11,2 @@ describe('String', function() {
       expect('test'.startsWith('te')).to.be.ok;
-    });
-
-    it('should be falsy on incorrect results', function() {
       expect('test'.startsWith('st')).to.not.be.ok;
@@ -19,2 +16,51 @@ expect(''.startsWith('/')).to.not.be.ok;
       expect('##'.startsWith('///')).to.not.be.ok;
+
+      expect('abc'.startsWith('abc')).to.be.ok;
+      expect('abcd'.startsWith('abc')).to.be.ok;
+      expect('abc'.startsWith('a')).to.be.ok;
+      expect('abc'.startsWith('abcd')).to.not.be.ok;
+      expect('abc'.startsWith('bcde')).to.not.be.ok;
+      expect('abc'.startsWith('b')).to.not.be.ok;
+      expect('abc'.startsWith('abc', 0)).to.be.ok;
+      expect('abc'.startsWith('bc', 0)).to.not.be.ok;
+      expect('abc'.startsWith('bc', 1)).to.be.ok;
+      expect('abc'.startsWith('c', 1)).to.not.be.ok;
+      expect('abc'.startsWith('abc', 1)).to.not.be.ok;
+      expect('abc'.startsWith('c', 2)).to.be.ok;
+      expect('abc'.startsWith('d', 2)).to.not.be.ok;
+      expect('abc'.startsWith('dcd', 2)).to.not.be.ok;
+      expect('abc'.startsWith('a', 42)).to.not.be.ok;
+      expect('abc'.startsWith('a', Infinity)).to.not.be.ok;
+      expect('abc'.startsWith('a', NaN)).to.be.ok;
+      expect('abc'.startsWith('b', NaN)).to.not.be.ok;
+      expect('abc'.startsWith('ab', -43)).to.be.ok;
+      expect('abc'.startsWith('ab', -Infinity)).to.be.ok;
+      expect('abc'.startsWith('bc', -42)).to.not.be.ok;
+      expect('abc'.startsWith('bc', -Infinity)).to.not.be.ok;
+      var myobj = {
+        toString: function() {return 'abc';},
+        startsWith: String.prototype.startsWith
+      };
+      expect(myobj.startsWith('abc')).to.be.ok;
+      expect(myobj.startsWith('bc')).to.not.be.ok;
+
+      var gotStr = false, gotPos = false;
+
+      myobj = {
+        toString: function() {
+          expect(gotPos).to.not.be.ok;
+          gotStr = true;
+          return 'xyz';
+        },
+        startsWith: String.prototype.startsWith
+      };
+      var idx = {
+        valueOf: function() {
+          expect(gotStr).to.be.ok;
+          gotPos = true;
+          return 42;
+        }
+      };
+      myobj.startsWith('elephant', idx);
+      expect(gotPos).to.be.ok;
     });
@@ -26,5 +72,2 @@ });
       expect('test'.endsWith('st')).to.be.ok;
-    })
-
-    it('should be falsy on incorrect results', function() {
       expect('test'.endsWith('te')).to.not.be.ok;
@@ -34,2 +77,51 @@ expect(''.endsWith('/')).to.not.be.ok;
       expect('##'.endsWith('///')).to.not.be.ok;
+
+      expect('abc'.endsWith('abc')).to.be.ok;
+      expect('abcd'.endsWith('bcd')).to.be.ok;
+      expect('abc'.endsWith('c')).to.be.ok;
+      expect('abc'.endsWith('abcd')).to.not.be.ok;
+      expect('abc'.endsWith('bbc')).to.not.be.ok;
+      expect('abc'.endsWith('b')).to.not.be.ok;
+      expect('abc'.endsWith('abc', 3)).to.be.ok;
+      expect('abc'.endsWith('bc', 3)).to.be.ok;
+      expect('abc'.endsWith('a', 3)).to.not.be.ok;
+      expect('abc'.endsWith('bc', 3)).to.be.ok;
+      expect('abc'.endsWith('a', 1)).to.be.ok;
+      expect('abc'.endsWith('abc', 1)).to.not.be.ok;
+      expect('abc'.endsWith('b', 2)).to.be.ok;
+      expect('abc'.endsWith('d', 2)).to.not.be.ok;
+      expect('abc'.endsWith('dcd', 2)).to.not.be.ok;
+      expect('abc'.endsWith('a', 42)).to.not.be.ok;
+      expect('abc'.endsWith('bc', Infinity)).to.be.ok;
+      expect('abc'.endsWith('a', Infinity)).to.not.be.ok;
+      expect('abc'.endsWith('bc', undefined)).to.be.ok;
+      expect('abc'.endsWith('bc', -43)).to.not.be.ok;
+      expect('abc'.endsWith('bc', -Infinity)).to.not.be.ok;
+      expect('abc'.endsWith('bc', NaN)).to.not.be.ok;
+
+      var myobj = {
+        toString: function() {return 'abc'},
+        endsWith: String.prototype.endsWith
+      };
+      expect(myobj.endsWith('abc')).to.be.ok;
+      expect(myobj.endsWith('ab')).to.not.be.ok;
+      var gotStr = false, gotPos = false;
+
+      myobj = {
+        toString: function() {
+          expect(gotPos).to.not.be.ok;
+          gotStr = true;
+          return 'xyz';
+        },
+        endsWith : String.prototype.endsWith
+      };
+      var idx = {
+        valueOf: function () {
+          expect(gotStr).to.be.ok;
+          gotPos = true;
+          return 42;
+        }
+      };
+      myobj.endsWith('elephant', idx);
+      expect(gotPos).to.be.ok;
     });
@@ -41,2 +133,58 @@ });
       expect('test'.contains('es')).to.be.ok;
+      expect('abc'.contains('a')).to.be.ok;
+      expect('abc'.contains('b')).to.be.ok;
+      expect('abc'.contains('abc')).to.be.ok;
+      expect('abc'.contains('bc')).to.be.ok;
+      expect('abc'.contains('d')).to.not.be.ok;
+      expect('abc'.contains('abcd')).to.not.be.ok;
+      expect('abc'.contains('ac')).to.not.be.ok;
+      expect('abc'.contains('abc', 0)).to.be.ok;
+      expect('abc'.contains('bc', 0)).to.be.ok;
+      expect('abc'.contains('de', 0)).to.not.be.ok;
+      expect('abc'.contains('bc', 1)).to.be.ok;
+      expect('abc'.contains('c', 1)).to.be.ok;
+      expect('abc'.contains('a', 1)).to.not.be.ok;
+      expect('abc'.contains('abc', 1)).to.not.be.ok;
+      expect('abc'.contains('c', 2)).to.be.ok;
+      expect('abc'.contains('d', 2)).to.not.be.ok;
+      expect('abc'.contains('dcd', 2)).to.not.be.ok;
+      expect('abc'.contains('a', 42)).to.not.be.ok;
+      expect('abc'.contains('a', Infinity)).to.not.be.ok;
+      expect('abc'.contains('ab', -43)).to.be.ok;
+      expect('abc'.contains('cd', -42)).to.not.be.ok;
+      expect('abc'.contains('ab', -Infinity)).to.be.ok;
+      expect('abc'.contains('cd', -Infinity)).to.not.be.ok;
+      expect('abc'.contains('ab', NaN)).to.be.ok;
+      expect('abc'.contains('cd', NaN)).to.not.be.ok;
+
+      var myobj = {
+        toString: function() {return 'abc';},
+        contains: String.prototype.contains
+      };
+
+      expect(myobj.contains('abc')).to.be.ok;
+      expect(myobj.contains('cd')).to.not.be.ok;
+
+      var gotStr = false, gotPos = false;
+
+      myobj = {
+        toString: function() {
+          expect(gotPos).to.not.be.ok;
+          gotStr = true;
+          return 'xyz';
+        },
+
+        contains: String.prototype.contains
+      };
+
+      var idx = {
+        valueOf: function() {
+          expect(gotStr).to.be.ok;
+          gotPos = true;
+          return 42;
+        }
+      };
+
+      myobj.contains('elephant', idx);
+      expect(gotPos).to.be.ok;
     });
@@ -43,0 +191,0 @@

New alerts

Non-existent author

Supply chain risk

The package was published by an npm account that no longer exists.

Found 1 instance in 1 package

Improved metrics

Total package byte prevSize

45898

increased by35.09%

Lines of code

1150

increased by32.34%

Worsened metrics

Number of high supply chain risk alerts

1

increased byInfinity%

No dependency changes