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Last active July 4, 2017 10:44
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A CasperJS script to test some JavaScript settings on our blog. This sample accompanies a blog post series about CasperJS found at
* @file
* Using CasperJS to run basic code tests on various libraries.
// Define the suite of tests and give it the following properties:
// - Title, which shows up before any of the pass/fails.
// - Number of tests, must be changed as you add tests.
// - suite(), which contains all of your tests.
// @see
casper.test.begin('Basic code tests for jQuery and Modernizr', 3, function suite(test) {
// You can output comments at any point in your script. Sometimes it's good
// to add a message when you're attempting an operation that might take a
// few moments to respond, such as this page load.
test.comment('⌚️ Opening');
// casper.start() always wraps your first action. The first argument should
// be the URL of the page you want to test.
// @see
casper.start('', function () {
// Look at a specific property on the jQuery object to check its version.
// assertEvalEquals provides an easy way for us to test JavaScript variables
// within the test environment. Any code within the assertEvalEquals() code
// block is considered to be part of the webpage, as if we are typing into
// the JS console of the fully-loaded page.
// @see
test.assertEvalEquals(function () {
return jQuery.fn.jquery;
}, '1.7.1', 'jQuery 1.7.1 was found.');
// Look at a specific property on the Modernizr object to check its version.
test.assertEvalEquals(function () {
return Modernizr._version;
}, '2.6.2', 'Modernizr 2.6.2 was found.');
// Check for required Modernizr tests. This is NOT testing the output! We
// are only testing whether Modernizr is working, not what its output is.
test.assertEvalEquals(function () {
// An array of strings. Each one represents a required test that must be
// found within Modernizr. That value might be true or false, but as long
// as it is boolean we ultimately do not care.
var requiredTests = [
// confirmedTests will end up as a single boolean. First, we map the
// requiredTests array and see if the global Modernizr object contains a
// boolean for each value we entered into requiredTests.
// Note: we're not testing the value of the Modernizr test result, but
// verifying that the test was present. Each browser will have a different
// result, so it's not very useful to verify Modernizr's output in a test
// environment.
var confirmedTests = {
// This should return the type of data (boolean), not the boolean value.
return typeof Modernizr[thisTest];
}).every(function(thisValue) {
// Each data type will be verified to be boolean, and the result of the
// .every() function will only be true if all the values resolved to true.
// If even one of the values is not boolean, .every() returns false.
return thisValue === 'boolean';
// Return the result of our computation to Casper. The return value of
// confirmedTests is ultimately what decides whether this test is reported
// as PASS or FAIL. All of the other computation beforehand was internal.
return confirmedTests;
}, true, 'Required Modernizr tests are all present. (inlinesvg, svg)');
// This code runs all the tests that we defined above.
// @see () {
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