File yui3/src/test/js/Assert.js
/**
* The Assert object provides functions to test JavaScript values against
* known and expected results. Whenever a comparison (assertion) fails,
* an error is thrown.
* @namespace Test
* @module test
* @class Assert
* @static
*/
YUITest.Assert = {
/**
* The number of assertions performed.
* @property _asserts
* @type int
* @private
*/
_asserts: 0,
//-------------------------------------------------------------------------
// Helper Methods
//-------------------------------------------------------------------------
/**
* Formats a message so that it can contain the original assertion message
* in addition to the custom message.
* @param {String} customMessage The message passed in by the developer.
* @param {String} defaultMessage The message created by the error by default.
* @return {String} The final error message, containing either or both.
* @protected
* @static
* @method _formatMessage
*/
_formatMessage : function (customMessage, defaultMessage) {
if (typeof customMessage == "string" && customMessage.length > 0){
return customMessage.replace("{message}", defaultMessage);
} else {
return defaultMessage;
}
},
/**
* Returns the number of assertions that have been performed.
* @method _getCount
* @protected
* @static
*/
_getCount: function(){
return this._asserts;
},
/**
* Increments the number of assertions that have been performed.
* @method _increment
* @protected
* @static
*/
_increment: function(){
this._asserts++;
},
/**
* Resets the number of assertions that have been performed to 0.
* @method _reset
* @protected
* @static
*/
_reset: function(){
this._asserts = 0;
},
//-------------------------------------------------------------------------
// Generic Assertion Methods
//-------------------------------------------------------------------------
/**
* Forces an assertion error to occur.
* @param {String} message (Optional) The message to display with the failure.
* @method fail
* @static
*/
fail : function (message) {
throw new YUITest.AssertionError(YUITest.Assert._formatMessage(message, "Test force-failed."));
},
/**
* A marker that the test should pass.
* @method pass
* @static
*/
pass : function (message) {
YUITest.Assert._increment();
},
//-------------------------------------------------------------------------
// Equality Assertion Methods
//-------------------------------------------------------------------------
/**
* Asserts that a value is equal to another. This uses the double equals sign
* so type coercion may occur.
* @param {Object} expected The expected value.
* @param {Object} actual The actual value to test.
* @param {String} message (Optional) The message to display if the assertion fails.
* @method areEqual
* @static
*/
areEqual : function (expected, actual, message) {
YUITest.Assert._increment();
if (expected != actual) {
throw new YUITest.ComparisonFailure(YUITest.Assert._formatMessage(message, "Values should be equal."), expected, actual);
}
},
/**
* Asserts that a value is not equal to another. This uses the double equals sign
* so type coercion may occur.
* @param {Object} unexpected The unexpected value.
* @param {Object} actual The actual value to test.
* @param {String} message (Optional) The message to display if the assertion fails.
* @method areNotEqual
* @static
*/
areNotEqual : function (unexpected, actual,
message) {
YUITest.Assert._increment();
if (unexpected == actual) {
throw new YUITest.UnexpectedValue(YUITest.Assert._formatMessage(message, "Values should not be equal."), unexpected);
}
},
/**
* Asserts that a value is not the same as another. This uses the triple equals sign
* so no type coercion may occur.
* @param {Object} unexpected The unexpected value.
* @param {Object} actual The actual value to test.
* @param {String} message (Optional) The message to display if the assertion fails.
* @method areNotSame
* @static
*/
areNotSame : function (unexpected, actual, message) {
YUITest.Assert._increment();
if (unexpected === actual) {
throw new YUITest.UnexpectedValue(YUITest.Assert._formatMessage(message, "Values should not be the same."), unexpected);
}
},
/**
* Asserts that a value is the same as another. This uses the triple equals sign
* so no type coercion may occur.
* @param {Object} expected The expected value.
* @param {Object} actual The actual value to test.
* @param {String} message (Optional) The message to display if the assertion fails.
* @method areSame
* @static
*/
areSame : function (expected, actual, message) {
YUITest.Assert._increment();
if (expected !== actual) {
throw new YUITest.ComparisonFailure(YUITest.Assert._formatMessage(message, "Values should be the same."), expected, actual);
}
},
//-------------------------------------------------------------------------
// Boolean Assertion Methods
//-------------------------------------------------------------------------
/**
* Asserts that a value is false. This uses the triple equals sign
* so no type coercion may occur.
* @param {Object} actual The actual value to test.
* @param {String} message (Optional) The message to display if the assertion fails.
* @method isFalse
* @static
*/
isFalse : function (actual, message) {
YUITest.Assert._increment();
if (false !== actual) {
throw new YUITest.ComparisonFailure(YUITest.Assert._formatMessage(message, "Value should be false."), false, actual);
}
},
/**
* Asserts that a value is true. This uses the triple equals sign
* so no type coercion may occur.
* @param {Object} actual The actual value to test.
* @param {String} message (Optional) The message to display if the assertion fails.
* @method isTrue
* @static
*/
isTrue : function (actual, message) {
YUITest.Assert._increment();
if (true !== actual) {
throw new YUITest.ComparisonFailure(YUITest.Assert._formatMessage(message, "Value should be true."), true, actual);
}
},
//-------------------------------------------------------------------------
// Special Value Assertion Methods
//-------------------------------------------------------------------------
/**
* Asserts that a value is not a number.
* @param {Object} actual The value to test.
* @param {String} message (Optional) The message to display if the assertion fails.
* @method isNaN
* @static
*/
isNaN : function (actual, message){
YUITest.Assert._increment();
if (!isNaN(actual)){
throw new YUITest.ComparisonFailure(YUITest.Assert._formatMessage(message, "Value should be NaN."), NaN, actual);
}
},
/**
* Asserts that a value is not the special NaN value.
* @param {Object} actual The value to test.
* @param {String} message (Optional) The message to display if the assertion fails.
* @method isNotNaN
* @static
*/
isNotNaN : function (actual, message){
YUITest.Assert._increment();
if (isNaN(actual)){
throw new YUITest.UnexpectedValue(YUITest.Assert._formatMessage(message, "Values should not be NaN."), NaN);
}
},
/**
* Asserts that a value is not null. This uses the triple equals sign
* so no type coercion may occur.
* @param {Object} actual The actual value to test.
* @param {String} message (Optional) The message to display if the assertion fails.
* @method isNotNull
* @static
*/
isNotNull : function (actual, message) {
YUITest.Assert._increment();
if (actual === null) {
throw new YUITest.UnexpectedValue(YUITest.Assert._formatMessage(message, "Values should not be null."), null);
}
},
/**
* Asserts that a value is not undefined. This uses the triple equals sign
* so no type coercion may occur.
* @param {Object} actual The actual value to test.
* @param {String} message (Optional) The message to display if the assertion fails.
* @method isNotUndefined
* @static
*/
isNotUndefined : function (actual, message) {
YUITest.Assert._increment();
if (typeof actual == "undefined") {
throw new YUITest.UnexpectedValue(YUITest.Assert._formatMessage(message, "Value should not be undefined."), undefined);
}
},
/**
* Asserts that a value is null. This uses the triple equals sign
* so no type coercion may occur.
* @param {Object} actual The actual value to test.
* @param {String} message (Optional) The message to display if the assertion fails.
* @method isNull
* @static
*/
isNull : function (actual, message) {
YUITest.Assert._increment();
if (actual !== null) {
throw new YUITest.ComparisonFailure(YUITest.Assert._formatMessage(message, "Value should be null."), null, actual);
}
},
/**
* Asserts that a value is undefined. This uses the triple equals sign
* so no type coercion may occur.
* @param {Object} actual The actual value to test.
* @param {String} message (Optional) The message to display if the assertion fails.
* @method isUndefined
* @static
*/
isUndefined : function (actual, message) {
YUITest.Assert._increment();
if (typeof actual != "undefined") {
throw new YUITest.ComparisonFailure(YUITest.Assert._formatMessage(message, "Value should be undefined."), undefined, actual);
}
},
//--------------------------------------------------------------------------
// Instance Assertion Methods
//--------------------------------------------------------------------------
/**
* Asserts that a value is an array.
* @param {Object} actual The value to test.
* @param {String} message (Optional) The message to display if the assertion fails.
* @method isArray
* @static
*/
isArray : function (actual, message) {
YUITest.Assert._increment();
var shouldFail = false;
if (Array.isArray){
shouldFail = !Array.isArray(actual);
} else {
shouldFail = Object.prototype.toString.call(actual) != "[object Array]";
}
if (shouldFail){
throw new YUITest.UnexpectedValue(YUITest.Assert._formatMessage(message, "Value should be an array."), actual);
}
},
/**
* Asserts that a value is a Boolean.
* @param {Object} actual The value to test.
* @param {String} message (Optional) The message to display if the assertion fails.
* @method isBoolean
* @static
*/
isBoolean : function (actual, message) {
YUITest.Assert._increment();
if (typeof actual != "boolean"){
throw new YUITest.UnexpectedValue(YUITest.Assert._formatMessage(message, "Value should be a Boolean."), actual);
}
},
/**
* Asserts that a value is a function.
* @param {Object} actual The value to test.
* @param {String} message (Optional) The message to display if the assertion fails.
* @method isFunction
* @static
*/
isFunction : function (actual, message) {
YUITest.Assert._increment();
if (!(actual instanceof Function)){
throw new YUITest.UnexpectedValue(YUITest.Assert._formatMessage(message, "Value should be a function."), actual);
}
},
/**
* Asserts that a value is an instance of a particular object. This may return
* incorrect results when comparing objects from one frame to constructors in
* another frame. For best results, don't use in a cross-frame manner.
* @param {Function} expected The function that the object should be an instance of.
* @param {Object} actual The object to test.
* @param {String} message (Optional) The message to display if the assertion fails.
* @method isInstanceOf
* @static
*/
isInstanceOf : function (expected, actual, message) {
YUITest.Assert._increment();
if (!(actual instanceof expected)){
throw new YUITest.ComparisonFailure(YUITest.Assert._formatMessage(message, "Value isn't an instance of expected type."), expected, actual);
}
},
/**
* Asserts that a value is a number.
* @param {Object} actual The value to test.
* @param {String} message (Optional) The message to display if the assertion fails.
* @method isNumber
* @static
*/
isNumber : function (actual, message) {
YUITest.Assert._increment();
if (typeof actual != "number"){
throw new YUITest.UnexpectedValue(YUITest.Assert._formatMessage(message, "Value should be a number."), actual);
}
},
/**
* Asserts that a value is an object.
* @param {Object} actual The value to test.
* @param {String} message (Optional) The message to display if the assertion fails.
* @method isObject
* @static
*/
isObject : function (actual, message) {
YUITest.Assert._increment();
if (!actual || (typeof actual != "object" && typeof actual != "function")){
throw new YUITest.UnexpectedValue(YUITest.Assert._formatMessage(message, "Value should be an object."), actual);
}
},
/**
* Asserts that a value is a string.
* @param {Object} actual The value to test.
* @param {String} message (Optional) The message to display if the assertion fails.
* @method isString
* @static
*/
isString : function (actual, message) {
YUITest.Assert._increment();
if (typeof actual != "string"){
throw new YUITest.UnexpectedValue(YUITest.Assert._formatMessage(message, "Value should be a string."), actual);
}
},
/**
* Asserts that a value is of a particular type.
* @param {String} expectedType The expected type of the variable.
* @param {Object} actualValue The actual value to test.
* @param {String} message (Optional) The message to display if the assertion fails.
* @method isTypeOf
* @static
*/
isTypeOf : function (expectedType, actualValue, message){
YUITest.Assert._increment();
if (typeof actualValue != expectedType){
throw new YUITest.ComparisonFailure(YUITest.Assert._formatMessage(message, "Value should be of type " + expectedType + "."), expectedType, typeof actualValue);
}
},
//--------------------------------------------------------------------------
// Error Detection Methods
//--------------------------------------------------------------------------
/**
* Asserts that executing a particular method should throw an error of
* a specific type. This is a replacement for _should.error.
* @param {String|Function|Object} expectedError If a string, this
* is the error message that the error must have; if a function, this
* is the constructor that should have been used to create the thrown
* error; if an object, this is an instance of a particular error type
* with a specific error message (both must match).
* @param {Function} method The method to execute that should throw the error.
* @param {String} message (Optional) The message to display if the assertion
* fails.
* @method throwsError
* @static
*/
throwsError: function(expectedError, method, message){
YUITest.Assert._increment();
var error = false;
try {
method();
} catch (thrown) {
//check to see what type of data we have
if (typeof expectedError == "string"){
//if it's a string, check the error message
if (thrown.message != expectedError){
error = true;
}
} else if (typeof expectedError == "function"){
//if it's a function, see if the error is an instance of it
if (!(thrown instanceof expectedError)){
error = true;
}
} else if (typeof expectedError == "object" && expectedError !== null){
//if it's an object, check the instance and message
if (!(thrown instanceof expectedError.constructor) ||
thrown.message != expectedError.message){
error = true;
}
} else { //if it gets here, the argument could be wrong
error = true;
}
if (error){
throw new YUITest.UnexpectedError(thrown);
} else {
return;
}
}
//if it reaches here, the error wasn't thrown, which is a bad thing
throw new YUITest.AssertionError(YUITest.Assert._formatMessage(message, "Error should have been thrown."));
}
};