Verify types on increase | decrease

lib/chai/core/assertions.js

@@ -224,7 +224,7 @@ module.exports = function (chai, _) {
    *     expect([1,2,3]).to.include(2);
    *     expect('foobar').to.contain('foo');
    *     expect({ foo: 'bar', hello: 'universe' }).to.include({ foo: 'bar' });
-   * 
+   *
    * By default, strict equality (===) is used. When asserting the inclusion of
    * a value in an array, the array is searched for an element that's strictly
    * equal to the given value. When asserting a subset of properties in an
@@ -319,7 +319,7 @@ module.exports = function (chai, _) {
 
       return;
     }
-    
+
     // Assert inclusion in an array or substring in a string.
     this.assert(
         typeof obj === 'string' || !isDeep ? ~obj.indexOf(val)
@@ -1764,7 +1764,7 @@ module.exports = function (chai, _) {
       if (!cmp) {
         var matchIdx = superset.indexOf(elem);
         if (matchIdx === -1) return false;
-       
+
         // Remove match from superset so not counted twice if duplicate in subset.
         if (!contains) superset.splice(matchIdx, 1);
         return true;
@@ -1961,7 +1961,7 @@ module.exports = function (chai, _) {
   /**
    * ### .increase(function)
    *
-   * Asserts that a function increases an object property
+   * Asserts that a function increases a numeric object property
    *
    *     var obj = { val: 10 };
    *     var fn = function() { obj.val = 15 };
@@ -1991,6 +1991,9 @@ module.exports = function (chai, _) {
       initial = target[prop];
     }
 
+    // Make sure that the target is a number
+    new Assertion(initial).is.a('number');
+
     fn();
 
     var final = prop === undefined || prop === null ? target() : target[prop];
@@ -2015,7 +2018,7 @@ module.exports = function (chai, _) {
   /**
    * ### .decrease(function)
    *
-   * Asserts that a function decreases an object property
+   * Asserts that a function decreases a numeric object property
    *
    *     var obj = { val: 10 };
    *     var fn = function() { obj.val = 5 };
@@ -2045,6 +2048,9 @@ module.exports = function (chai, _) {
       initial = target[prop];
     }
 
+    // Make sure that the target is a number
+    new Assertion(initial).is.a('number');
+
     fn();
 
     var final = prop === undefined || prop === null ? target() : target[prop];

lib/chai/interface/assert.js

@@ -2182,7 +2182,7 @@ module.exports = function (chai, util) {
   /**
    * ### .increases(function, object, property, [message])
    *
-   * Asserts that a function increases an object property
+   * Asserts that a function increases a numeric object property
    *
    *     var obj = { val: 10 };
    *     var fn = function() { obj.val = 13 };
@@ -2209,7 +2209,7 @@ module.exports = function (chai, util) {
   /**
    * ### .increasesBy(function, object, property, delta, [message])
    *
-   * Asserts that a function increases an object property or a function's return value by an amount (delta)
+   * Asserts that a function increases a numeric object property or a function's return value by an amount (delta)
    *
    *     var obj = { val: 10 };
    *     var fn = function() { obj.val += 10 };
@@ -2241,7 +2241,7 @@ module.exports = function (chai, util) {
   /**
    * ### .doesNotIncrease(function, object, property, [message])
    *
-   * Asserts that a function does not increase object property
+   * Asserts that a function does not increase a numeric object property
    *
    *     var obj = { val: 10 };
    *     var fn = function() { obj.val = 8 };
@@ -2268,7 +2268,7 @@ module.exports = function (chai, util) {
   /**
    * ### .increasesButNotBy(function, object, property, [message])
    *
-   * Asserts that a function does not increase object property or function's return value by an amount (delta)
+   * Asserts that a function does not increase a numeric object property or function's return value by an amount (delta)
    *
    *     var obj = { val: 10 };
    *     var fn = function() { obj.val = 15 };
@@ -2300,7 +2300,7 @@ module.exports = function (chai, util) {
   /**
    * ### .decreases(function, object, property, [message])
    *
-   * Asserts that a function decreases an object property
+   * Asserts that a function decreases a numeric object property
    *
    *     var obj = { val: 10 };
    *     var fn = function() { obj.val = 5 };
@@ -2327,7 +2327,7 @@ module.exports = function (chai, util) {
   /**
    * ### .decreasesBy(function, object, property, delta, [message])
    *
-   * Asserts that a function decreases an object property or a function's return value by an amount (delta)
+   * Asserts that a function decreases a numeric object property or a function's return value by an amount (delta)
    *
    *     var obj = { val: 10 };
    *     var fn = function() { obj.val -= 5 };
@@ -2359,7 +2359,7 @@ module.exports = function (chai, util) {
   /**
    * ### .doesNotDecrease(function, object, property, [message])
    *
-   * Asserts that a function does not decreases an object property
+   * Asserts that a function does not decreases a numeric object property
    *
    *     var obj = { val: 10 };
    *     var fn = function() { obj.val = 15 };
@@ -2386,7 +2386,7 @@ module.exports = function (chai, util) {
   /**
    * ### .doesNotDecreaseBy(function, object, property, delta, [message])
    *
-   * Asserts that a function does not decreases an object property or a function's return value by an amount (delta)
+   * Asserts that a function does not decreases a numeric object property or a function's return value by an amount (delta)
    *
    *     var obj = { val: 10 };
    *     var fn = function() { obj.val = 5 };
@@ -2418,7 +2418,7 @@ module.exports = function (chai, util) {
   /**
    * ### .decreasesButNotBy(function, object, property, delta, [message])
    *
-   * Asserts that a function does not decreases an object property or a function's return value by an amount (delta)
+   * Asserts that a function does not decreases a numeric object property or a function's return value by an amount (delta)
    *
    *     var obj = { val: 10 };
    *     var fn = function() { obj.val = 5 };

test/assert.js

@@ -365,7 +365,7 @@ describe('assert', function () {
   it('exists', function() {
     var meeber = 'awesome';
     var iDoNotExist;
-       
+
     assert.exists(meeber);
     assert.exists(0);
     assert.exists(false);
@@ -379,7 +379,7 @@ describe('assert', function () {
   it('notExists', function() {
     var meeber = 'awesome';
     var iDoNotExist;
-       
+
     assert.notExists(iDoNotExist);
 
     err(function (){
@@ -728,7 +728,7 @@ describe('assert', function () {
       var aKey = {thisIs: 'anExampleObject'}
         , anotherKey = {doingThisBecauseOf: 'referential equality'}
         , testMap = new Map();
-      
+
       testMap.set(aKey, 'aValue');
       testMap.set(anotherKey, 'anotherValue');
 
@@ -751,7 +751,7 @@ describe('assert', function () {
         , weirdMapKey2 = {toString: NaN}
         , weirdMapKey3 = []
         , weirdMap = new Map();
-      
+
       weirdMap.set(weirdMapKey1, 'val1');
       weirdMap.set(weirdMapKey2, 'val2');
 
@@ -763,7 +763,7 @@ describe('assert', function () {
           , symMapKey2 = Symbol()
           , symMapKey3 = Symbol()
           , symMap = new Map();
-        
+
         symMap.set(symMapKey1, 'val1');
         symMap.set(symMapKey2, 'val2');
 
@@ -825,7 +825,7 @@ describe('assert', function () {
       var aKey = {thisIs: 'anExampleObject'}
         , anotherKey = {doingThisBecauseOf: 'referential equality'}
         , testSet = new Set();
-      
+
       testSet.add(aKey);
       testSet.add(anotherKey);
 
@@ -848,7 +848,7 @@ describe('assert', function () {
         , weirdSetKey2 = {toString: NaN}
         , weirdSetKey3 = []
         , weirdSet = new Set();
-      
+
       weirdSet.add(weirdSetKey1);
       weirdSet.add(weirdSetKey2);
 
@@ -860,7 +860,7 @@ describe('assert', function () {
           , symSetKey2 = Symbol()
           , symSetKey3 = Symbol()
           , symSet = new Set();
-        
+
         symSet.add(symSetKey1);
         symSet.add(symSetKey2);
 
@@ -873,7 +873,7 @@ describe('assert', function () {
       }
 
       var errSet = new Set();
-      
+
       errSet.add({1: 20});
       errSet.add('number');
 
@@ -1693,6 +1693,13 @@ describe('assert', function () {
     err(function() {
       assert.isAtLeast(1, 3);
     }, 'expected 1 to be at least 3');
+
+    err(function() {
+      assert.isAtLeast(null, 1);
+    }, 'expected null to be a number');
+    err(function() {
+      assert.isAtLeast(1, null);
+    }, 'the argument to least must be a number');
   });
 
   it('below', function() {
@@ -1722,6 +1729,13 @@ describe('assert', function () {
     err(function() {
       assert.isAtMost(3, 1);
     }, 'expected 3 to be at most 1');
+
+    err(function() {
+      assert.isAtMost(null, 1);
+    }, 'expected null to be a number');
+    err(function() {
+      assert.isAtMost(1, null);
+    }, 'the argument to most must be a number');
   });
 
   it('change', function() {
@@ -1749,7 +1763,7 @@ describe('assert', function () {
   });
 
   it('increase, decrease', function() {
-    var obj = { value: 10 },
+    var obj = { value: 10, noop: null },
         arr = ['one', 'two'],
         pFn   = function() { arr.push('three') },
         popFn = function() { arr.pop() },
@@ -1777,6 +1791,13 @@ describe('assert', function () {
     assert.doesNotIncrease(popFn, lenFn);
     assert.increasesBy(pFn, lenFn, 1);
     assert.increasesButNotBy(pFn, lenFn, 2);
+
+    err(function() {
+      assert.increases(incFn, obj, 'noop');
+    }, 'expected null to be a number');
+    err(function() {
+      assert.decreases(incFn, obj, 'noop');
+    }, 'expected null to be a number');
   });
 
   it('isExtensible / extensible', function() {

test/expect.js

@@ -603,7 +603,7 @@ describe('expect', function () {
     err(function(){
       expect().to.not.be.empty;
     }, "expected undefined to exist");
-    
+
   });
 
   it('NaN', function() {
@@ -797,7 +797,7 @@ describe('expect', function () {
       expect(obj).to.not.have.deep.property('a', {b: 1}, 'blah');
     }, "blah: expected { a: { b: 1 } } to not have a deep property 'a' of { b: 1 }");
   });
-  
+
   it('nested.property(name, val)', function(){
     expect({ foo: { bar: 'baz' } })
       .to.have.nested.property('foo.bar', 'baz');
@@ -1182,7 +1182,7 @@ describe('expect', function () {
       var aKey = {thisIs: 'anExampleObject'}
         , anotherKey = {doingThisBecauseOf: 'referential equality'}
         , testMap = new Map();
-      
+
       testMap.set(aKey, 'aValue');
       testMap.set(anotherKey, 'anotherValue');
 
@@ -1209,7 +1209,7 @@ describe('expect', function () {
         , weirdMapKey2 = {toString: NaN}
         , weirdMapKey3 = []
         , weirdMap = new Map();
-      
+
       weirdMap.set(weirdMapKey1, 'val1');
       weirdMap.set(weirdMapKey2, 'val2');
 
@@ -1221,7 +1221,7 @@ describe('expect', function () {
           , symMapKey2 = Symbol()
           , symMapKey3 = Symbol()
           , symMap = new Map();
-        
+
         symMap.set(symMapKey1, 'val1');
         symMap.set(symMapKey2, 'val2');
 
@@ -1262,7 +1262,7 @@ describe('expect', function () {
       var aKey = {thisIs: 'anExampleObject'}
         , anotherKey = {doingThisBecauseOf: 'referential equality'}
         , testSet = new Set();
-      
+
       testSet.add(aKey);
       testSet.add(anotherKey);
 
@@ -1289,7 +1289,7 @@ describe('expect', function () {
         , weirdSetKey2 = {toString: NaN}
         , weirdSetKey3 = []
         , weirdSet = new Set();
-      
+
       weirdSet.add(weirdSetKey1);
       weirdSet.add(weirdSetKey2);
 
@@ -1301,7 +1301,7 @@ describe('expect', function () {
           , symSetKey2 = Symbol()
           , symSetKey3 = Symbol()
           , symSet = new Set();
-        
+
         symSet.add(symSetKey1);
         symSet.add(symSetKey2);
 
@@ -1898,7 +1898,7 @@ describe('expect', function () {
   });
 
   it('increase, decrease', function() {
-    var obj = { value: 10 },
+    var obj = { value: 10, noop: null },
         arr = ['one', 'two'],
         pFn   = function() { arr.push('three') },
         popFn = function() { arr.pop() },
@@ -1931,6 +1931,13 @@ describe('expect', function () {
     expect(popFn).to.decrease(lenFn).but.not.by(2);
     expect(nFn).to.not.decrease(lenFn);
     expect(pFn).to.not.decrease(lenFn);
+
+    err(function() {
+      expect(incFn).to.increase(obj, 'noop');
+    }, 'expected null to be a number');
+    err(function() {
+      expect(incFn).to.decrease(obj, 'noop');
+    }, 'expected null to be a number');
   });
 
   it('extensible', function() {