“Jasmine (taxonomic name Jasminum /ˈdʒæzmɨnəm/) is a genus of shrubs and vines in the olive family (Oleaceae)” — Wikipedia
Jasminum is a JavaScript testing scaffold. Jasminum is designed to accept Jasmine 1.3 “specs” with very little modification. However, it has a minimal but modular and extensible core, supports and uses promises for asynchronous tests, and has an “isomorphic” API, meaning Jasminum tests can be run without modification between Node.js and browsers using CommonJS module loaders including Browserify, Mr, or Mop.
Jasminum is built for debugging and isolation, not merely a regression trip-wire. Instead of trying to patch the universe so that all context gets funneled into pretty reports, Jasminum reports to the console. You do not need to isolate which test was running when that message got dumped to the console. Jasminum includes reporters for Node.js, PhantomJS, and browser based tests. The reporter only highlights lines of interest. It highlights the spec in stack traces. The test summary only shows green if all tests pass. The test summary only shows red if any tests fail. The test summary only highlights skipped tests if there were any.
First, write a test.
// test/my-test.js
describe("my library", function () {
it("should work", function () {
expect(10).toBeLessThan(20);
});
});
You can install the jasminum
command using npm
. I recommend installing
Jasminum in your project so the version gets saved in your package.json
and so
you can use different versions in your various projects.
❯ npm install jasminum --save-dev
Or, if necessary, install globally.
❯ [sudo] npm install jasminum -g
Use jasminum
to run your test. jasminum
will run all test files specified,
or all *-test.js
and *-spec.js
files within each specified directory.
❯ jasminum test
1 tests passed
1 assertions passed
0 tests failed
0 assertions failed
0 errors
0 tests skipped
The results will be colored to draw your attention either to passed, failed, or
skipped tests depending on the situation. You can use iit
and ddescribe
to
focus on certain tests, skipping all others. You can use xit
and xdescribe
to skip certain tests.
You can use the -f
command line flag to only show information about failed
tests. Because the test runner does not know whether to show the name of the
test until it fails, test names, and all of their parent suite names, will be
logged after the test fails instead of before. Arrows draw your attention to
this nuance.
With PhantomJS installed, Jasminum can run the same tests in the PhantomJS headless browser. The interface and reports are identical.
❯ jasminum-phantom test
1 tests passed
1 assertions passed
0 tests failed
0 assertions failed
0 errors
0 tests skipped
You can create an “isomorphic” test runner that you can use to run tests in Node.js directly, or using a browser module loader, or to measure test coverage.
// test/index.js
var Suite = require("jasminum");
new Suite("my tests").describe(function () {
require("./my-test");
}).runAndReport().done();
Create a test script in your package.json
:
{
"scripts": {
"test": "node test/index.js"
}
}
Now, npm test
will run your tests.
To run the same tests in a web browser, use npm install mr@~0.13.3 --save-dev
and use the following HTML test scaffold.
<!-- test/index.html -->
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<link rel="stylesheet" type="text/css"
href="../node_modules/jasminum/jasminum.css">
<script
src="../node_modules/mr/bootstrap.js" data-package=".."
data-module="test/index"></script>
</head>
<body>
</body>
</html>
The page under test will be blank. You can use this space as a stage for your tests. The test runner reports directly to your web inspector console. It will change the background color to grey while tests are running, red when the first test fails, or green if all tests complete without any failures.
To get test coverage measurements, use npm install istanbul@~0.2.4 --save-dev
and npm install opener --save-dev
and add a script to your package.json
.
This will cause npm run cover
to run coverage and display the results.
{
"devDependencies": {
"jasminum": "~1.0",
"mr": "~0.13.3",
"istanbul": "~0.2.4",
"opener": "*"
},
"scripts": {
"test": "jasminum test",
"test:phantom": "jasminum-phantom test",
"cover": "istanbul cover test/index.js && istanbul report html && opener coverage/index.html"
}
}
Jasminum supports asynchronous tests that either use a done
callback or
return a promise.
describe("an asynchronous task", function () {
it("waits for one second using done", function (done) {
setTimeout(done, 1000);
});
it("waits for one second using a promise", function () {
return Q().delay(1000);
});
});
If a test returns a promise, it is expected to be fulfilled with undefined
.
Jasminum does not support runs
or waitsFor
.
At time of writing, Jasminum weighs less than a KLOC. This is largely because it delegates large responsibilities to Montage Collections and the Q promise library.
Jasminum is loosely coupled to Q. You can substitute any promise library that
supports a Promise
constructor and a Promise.resolve
method, per
ECMAScript 6. Create a constructor that inherits from Jasminum’s Suite
and
override its Promise
property, or just pass Promise
as an option to
suite.runAndReport(options)
.
The Collections library establishes foundations that Jasminum employs for
comparing values, particularly polymorphic Object.equals
, Object.compare
,
and Object.has
operators, as well as the non-polymorphic Object.is
operator.
These do not behave exactly the same way as Jasmine, but are designed with
extensibility in mind both within and beyond testing. Partcularly, “any” objects
simply override their “equals” method to recognize any object of the same type
as equivalent.
“The scare quotes will come off when I say they come off.” — Math
Jasminum supports an “isomorphic” test runner. The following test can be run in
Node.js with node test/index.js
// test/index.js
var Suite = require("jasminum");
var suite = new Suite("Q").describe(function () {
require("./q");
require("./eta");
require("./traces");
require("./never-again");
require("./node");
require("./queue");
});
suite.runAndReport().done();
It can also be run with Mr with no modification.
<!-- test/index.html -->
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<link rel="stylesheet" type="text/css"
href="../node_modules/jasminum/jasminum.css">
<script
src="../node_modules/mr/boot.js" data-package=".."
data-module="test/index"></script>
</head>
<body>
</body>
</html>
The default test reporter for Node.js and for browsers are designed with
debugging in mind. Either way, all results are reported to the console as they
are executed. The scaffold logs messages between tests to assist in isolating
problems. Jasminum does not use clever techniques to capture or interfere with
standard output and console messages. In the browser, the inspected window is
left as a stage for the application under test and the test runner will only
fiddle with the testing
, pass
, and fail
classes of the body
element.
In addition to describe
and it
, Jasmine and Jasminum both support xdescribe
and xit
to quickly or temporarily disable a test. In addition, Jasminum
supports ddescribe
and iit
that will cause the test runner to focus
on the annotated suites or tests.
Jasminum only runs in CommonJS module loaders.
Jasminum will not include a mock clock. Please seek refuge in npm
.
Jasminum does not attempt to capture errors in the “domain” of a test. Promises will usually funnel exceptions into the test scaffold, but if you throw an error from a timeout event, or any other kind of event, Jasminum will stop exactly where the problem occurred.
Jasminum does not redirect standard IO or console messages to the test reporter. Jasminum instead elects to direct its reports to the console and standard IO so that it interleaves the chronology of your program.
Jasminum only provides reporters for Node.js and console browsing.
Jasminum does not automatically run tests whenever tests or their dependencies change, but such a contraption is easy to imagine based on the dependency graph that Mr can produce.
Jasminum provides Jasmine 1.3 spies to ease migration. However, please migrate to an external spy package like Sinon for spies. Jasmine spies will be removed in a future release.
Jasminum compensates for its minimalism with extensibility.
By way of background, the DSL provides a few extra methods. getCurrentSuite
returns the suite instance for the containing describe
block, both at
declaration time and at test time. getCurrentTest
returns the current test
instances at test time, and getCurrentReport
returns the current report at
test time. There is no current test or report at declaration time.
Jasminum also supports corresponding set
methods, but these are intended only
for the use of the test runner.
Jasminum expectations can be extended in a variety of ways.
The current suite will always have an Expectation
property, that the suite
will use to construct expectation instances when the test calls expect
. Each
nested suite, in a describe
block, will have a prototypically inherited child
of the parent Expectation
constructor to isolate any extensions to the
expectation.
The simplest is to provide overrides for existing expectation methods. Any
object can implement equals
or compare
, which will affect the behavior of
toEqual
, toBeLessThan
, toBeGreaterThan
, toBeNear
and toBeCloseTo
.
Look into Montage Collections for details about these generic methods.
You can create custom expectation constructors. The Jasminum Expecatation
constructor provides an assert
method that makes most expectations
implementable with a single call to this utility method. It handles the case
where the expectation has been negated and gives the reporter great flexibility
in rendering the involved objects and negating the messages.
function FunnyExpectation(value, report, test) {
Expectation.call(this, value, report, test);
// Also sets up the .not.isNot = true, .not.not = this stuff
};
FunnyExpectation.prototype = Object.create(Expectation.prototype);
FunnyExpectation.prototype.constructor = FunnyExpectation;
FunnyExpectation.prototype.toBeFunny = function () {
var isFunny = this.value.isFunny();
this.assert(isFunny, ["expected", "[not] to be funny"], [this.value]);
};
Any value can implement expect(report)
and return a custom expectation for
that object. expect(value)
will delegate to value.expect(getCurrentReport())
and return your custom expectation object. This is best illustrated by the spy
and spy-expectation
modules which use this facility to provide special methods
for spies.
function Clown(funny, scary) {
this.funny = funny;
this.scary = scary;
}
Clown.prototype.expect = function (report) {
return new FunnyExpectation(this, report);
};
Also, every suite has a specialized copy of the Expectation
type from its
parent suite. Methods can be added to the Expectation.prototype
or the
Expectation
constructor can be replaced outright and the change will only
apply in the current scope.
var Expectation = require("jasminum/expectation");
describe("funny objects", function () {
getCurrentSuite().Expectation = FunnyExpecation;
it("are funny", function () {
expect(new ClownShoes()).toBeFunny();
expect(new Clown()).not.toBeFunny();
});
});
Jasminum provides a console reporter that is suitable for tests run by Node.js, or tests run through PhantomJS and forwarded to the Node.js console. It also provides a reporter suitable for running tests in an arbitrary browser, reporting results to the browser console.
However, tests can be run with an arbitrary reporter. The Suite runAndReport
and runAndReportSync
methods both accept an options
object which may include
either a report
or Reporter
constructor. If neither are provided, it falls
back to calling the Reporter
on its prototype chain, so Suites can be extended
to have an alternate default reporter. The Suite shares the run-and-report
options
with the reporter constructor.
The Reporter must implement:
start(test) -> reporter
: returns a nested reporter instance for the given test.end(test)
: concludes a test. This is a good point to check whether any assertions have failed and to calculate and propagate the test’s statistics.skip(test)
: notes that the test has been skipped.end
will still be called.error(error, test)
: notes that an error was thrown while running the test, albeit in a promise handler.end
will still be called.assert(guard, isNot, messages, objects)
: reports on an assertion.
The guard may be a truthy or falsy value, but will be either exactly true
or
false
. isNot
indicates that the assertion is negative, so the guard
has
the opposite meaning, and if any of the messages
contain the phrase " [not]"
, these must be replaced with " not"
. Otherwise, these phrases must be
replaced with an empty string. The objects are intended to be interleaved after
the corresponding message and there may be more messages than objects, or more
objects than messages.
The Reporter may implement:
enter()
exit(exiting)
The suite runner will call enter
once before running tests, and exit
once
after running all tests. If the tests are exiting prematurely, the exiting
flag will be true, in which case, it would be innapropriate to call
process.exit
because doing so would prevent Node.js from printing an uncaught
exception to the console.
The Suite
constructor can be extended. The Suite
is not hard-coded to use
the basic Test
, Expectation
, and Reporter
constructors. Specialized
expectations and tests can be overridden on the Suite.prototype
.
Jasminum provides a reporter
module with an alternate browser-reporter
implementation that will be used in place of reporter
automatically if it is
loaded by Browserify, Mr, or Mop.