support other assertion libraries

[flosse]

It would be great if you can use another libs like chai.js or should.js

[cjohansen]

If they throw AssertionErrors they can be thrown right in. Otherwise they need a little bit of glue, we already have several hooks available. Want to take a stab at integrating them?

[cjohansen]

Both of these throw AssertionErrors, so there's nothing to do to support them. Just add them as libraries in your project and use at will.

[flosse]

There is still WARNING: No assertions!. Where is my mistake?

buster  = require "buster"
app     = require "../src/myApp"
chai    = require('chai').should()

buster.testCase 'does chai work?',

  'hello chai': ->
    "a".should.equal "b"

Failure: does chai work? hello chai
    expected 'a' to equal 'b'

1 test case, 1 test, 0 assertions, 1 failure, 0 errors, 0 timeouts
WARNING: No assertions!

edit: same problem with should.js

[cjohansen]

Ah, so Buster will catch the errors, but is never notified of success. That requires a (very small) extension to do. If you don't want to do it, you can silence the error:

buster.testRunner.failOnNoAssertions = false;

However, by doing that you're opting out of potentially very useful information. A better approach would be to create a small buster-chai extension that pings buster on assertion success.

[flosse]

Are there any docs/tutorials/examples how to create buster extensions? Or could you give me some hints where to start studying the buster code?

[magnars]

buster-chai should be a subset of buster-jstestdriver code. Check that out first. :-) https://github.com/busterjs/buster-jstestdriver

[flosse]

@magnars: thx, I'll have look at it and hopefully I'll be able to write the extension.

[magnars]

@flosse Don't be discouraged by the size of buster-jstestdriver, it does quite a bit more than you need to do. I'm sure @cjohansen can give you a more precise starting point.

[cjohansen]

Actually, you don't need an extension for this, you only need a wrapper module. This is how buster-assertions integrates with the runner:

    var buster = require("buster-test");
    buster.assertions = require("buster-assertions");
    var assertions = 0;
    var count = function () { assertions += 1; };
    buster.assertions.on("pass", count);
    buster.assertions.on("failure", count);
    buster.testRunner.assertionCount = function () {
        return assertions;
    };

Looking at this I'm not very impressed, to be honest. Should probably just be something like buster.testRunner.countAssertion().

[flosse]

Hey buster.js team! Unfortunately I still couldn't find some time to implement an extension. Are the any new changes so far that makes it possible to use chai.js easily?