Testing with Karma and RequireJS with files in CommonJS syntax
I'm working on an angular application that is written in CommonJS syntax and uses a grunt task with the grunt-contrib-requirejs task to translate the source files to AMD format and compile it into one output file. My goal is to make Karma work with RequireJS and keep my source files and spec files in CommonJS syntax.
I've been able to get a simple test passing in AMD format with the following file structure:
-- karma-test
|-- spec
| `-- exampleSpec.js
|-- src
| `-- example.js
|-- karma.conf.js
`-- test-main.js
and the following files:
karma.conf.js
// base path, that will be used to resolve files and exclude
basePath = '';
// list of files / patterns to load in the browser
files = [
JASMINE,
JASMINE_ADAPTER,
REQUIRE,
REQUIRE_ADAPTER,
'test-main.js',
{pattern: 'src/*.js', included: false},
{pattern: 'spec/*.js', included: false}
];
// list of files to exclude
exclude = [];
// test results reporter to use
// possible values: 'dots', 'progress', 'junit'
reporters = ['progress'];
// web server port
port = 9876;
// cli runner port
runnerPort = 9100;
// enable / disable colors in the output (reporters and logs)
colors = true;
// level of logging
// possible values: LOG_DISABLE || LOG_ERROR || LOG_WARN || LOG_INFO || LOG_DEBUG
logLevel = LOG_DEBUG;
// enable / disable watching file and executing tests whenever any file changes
autoWatch = true;
// Start these browsers, currently available:
browsers = ['Chrome'];
// If browser does not capture in given timeout [ms], kill it
captureTimeout = 60000;
// Continuous Integration mode
// if true, it capture browsers, run tests and exit
singleRun = false;
example.js
define('example', function() {
var message = "Hello!";
return {
message: message
};
});
exampleSpec.js
define(['example'], function(example) {
describe("Example", function() {
it("should have a message equal to 'Hello!'", function() {
expect(example.message).toBe('Hello!');
});
});
});
test-main.js
var tests = Object.keys(window.__karma__.files).filter(function (file) {
return /Spec\.js$/.test(file);
});
requirejs.config({
// Karma serves files from '/base'
baseUrl: '/base/src',
// Translate CommonJS to AMD
cjsTranslate: true,
// ask Require.js to load these files (all our tests)
deps: tests,
// start test run, once Require.js is done
callback: window.__karma__.start
});
However, my goal is to write both the source file and the spec file in CommonJS syntax with the same results, like so:
example.js
var message = "Hello!";
module.exports = {
message: message
};
exampleSpec.js
var example = require('example');
describe("Example", function() {
it("should have a message equal to 'Hello!'", function() {
expect(example.message).toBe('Hello!');
});
});
But despite having the cjsTranslate flag set to true, I just receive this error:
Uncaught Error: Module name "example" has not been loaded yet for context: _. Use require([])
http://requirejs.org/docs/errors.html#notloaded
at http://localhost:9876/adapter/lib/require.js?1371450058000:1746
Any ideas on how this can be accomplished?
Edit: I found this issue for the karma-runner repo: https://github.com/karma-runner/karma/issues/552 and there's a few comments that may help with this problem, but I haven't had any luck with them so far.
Answer
The solution I ended up finding involved using grunt and writing some custom grunt tasks. The process goes like this:
Create a grunt task to build a bootstrap requirejs file by finding all specs using a file pattern, looping through them and building out a traditional AMD style require block and creating a temporary file with code like this:
require(['spec/example1_spec.js'
,'spec/example2_spec.js',
,'spec/example3_spec.js'
],function(a1,a2){
// this space intentionally left blank
}, "", true);
Create a RequireJS grunt task that compiles the above bootstrap file and outputs a single js file that will effectively include all source code, specs, and libraries.
requirejs: { tests: { options: { baseUrl: './test', paths: {}, // paths object for libraries shim: {}, // shim object for non-AMD libraries // I pulled in almond using npm name: '../node_modules/almond/almond.min', // This is the file we created above include: 'tmp/require-tests', // This is the output file that we will serve to karma out: 'test/tmp/tests.js', optimize: 'none', // This translates commonjs syntax to AMD require blocks cjsTranslate: true } } }
Create a grunt task that manually starts a karma server and serve the single compiled js file that we now have for testing.
Additionally, I was able to ditch the REQUIRE_ADAPTER in the karma.conf.js file and then only include the single compiled js file instead of the patterns that matched all source code and specs, so it looks like this now:
// base path, that will be used to resolve files and exclude
basePath = '';
// list of files / patterns to load in the browser
files = [
JASMINE,
JASMINE_ADAPTER,
REQUIRE,
'tmp/tests.js'
];
// list of files to exclude
exclude = [];
// test results reporter to use
// possible values: 'dots', 'progress', 'junit'
reporters = ['progress'];
// web server port
port = 9876;
// cli runner port
runnerPort = 9100;
// enable / disable colors in the output (reporters and logs)
colors = true;
// level of logging
// possible values: LOG_DISABLE || LOG_ERROR || LOG_WARN || LOG_INFO || LOG_DEBUG
logLevel = LOG_INFO;
// enable / disable watching file and executing tests whenever any file changes
autoWatch = true;
// Start these browsers, currently available:
browsers = ['PhantomJS'];
// If browser does not capture in given timeout [ms], kill it
captureTimeout = 60000;
// Continuous Integration mode
// if true, it capture browsers, run tests and exit
singleRun = true;
In the grunt task configuration for the requirejs compilation, it was also necessary to use almond in order to start the test execution (test execution would hang without it). You can see this used in the requirejs grunt task config above.