hangs karma

when starting karma with callback:

var karma = require('karma');
var opts = {
    configFile: __dirname + '/karma.conf.js',
    singleRun: true
};
new karma.Server(opts, () => null).start();

coverage causes the process to hang after running the tests.

using karma.conf.js:

module.exports = function(config) {
  config.set({
    files: ['test.js'],
    frameworks: ['jasmine'],
    reporters: ['coverage'],
    coverageReporter: {
        reporters: [{type: 'text'}]
    },
    port: 9876,
    browsers: ['PhantomJS'],
    plugins: [
        'karma-jasmine',
        'karma-phantomjs-launcher',
        'karma-coverage'
    ]
  })
}

The process exits normally if either: no callback is passed to the Server constructor, or the coverage reporter is disabled.

I notice there is no change in coverage that caused this issue; it may be related to socketio/socket.io#2368 ?

[bjacobel]

I have this same issue. For me, it seems to be related specifically to the text-summary reporter.

        coverageReporter: {
            dir: 'build', subdir: 'coverage-js',
            reporters: [
                {type: 'html', subdir: 'coverage-js/html'},
                {type: 'cobertura', file: 'coverage.xml'},
                {type: 'lcov', dir: 'coverage/'},
                {type: 'text-summary'}
            ]
        }

$> time npm test
> edx-ui-toolkit@0.9.1 test /Users/bjacobel/code/edx-ui-toolkit
> gulp test

[11:12:17] Using gulpfile ~/code/edx-ui-toolkit/gulpfile.js
[11:12:17] Starting 'test'...
< ... test output>
=============================== Coverage summary ===============================
Statements   : 92.81% ( 774/834 )
Branches     : 65.38% ( 119/182 )
Functions    : 95.51% ( 234/245 )
Lines        : 92.78% ( 771/831 )
================================================================================
[11:12:18] Finished 'test' after 1.89 s

real    0m34.425s
user    0m3.619s
sys 0m0.602s

But after removing the text-summary reporter:

        coverageReporter: {
            dir: 'build', subdir: 'coverage-js',
            reporters: [
                {type: 'html', subdir: 'coverage-js/html'},
                {type: 'cobertura', file: 'coverage.xml'},
                {type: 'lcov', dir: 'coverage/'}
            ]
        }

$> time npm test

> edx-ui-toolkit@0.9.1 test /Users/bjacobel/code/edx-ui-toolkit
> gulp test

[11:13:55] Using gulpfile ~/code/edx-ui-toolkit/gulpfile.js
[11:13:55] Starting 'test'...
< ... test output>
[11:13:56] Finished 'test' after 1.61 s

real    0m3.536s
user    0m3.271s
sys 0m0.451s

(Similar results when using the text reporter as a substitute for text-summary.)

Interestingly, it’s not taking that 30sec to produce the coverage output, as the 30sec hang is after the text-summary coverage is output.

[9still]

At least in our case, this appears to have something to do with console output happening after text output is written to the console.

e.g.

...
---------------------------------------------|----------|----------|----------|----------|----------------|
All files                                    |    99.99 |    99.99 |    99.99 |    99.99 |                |
---------------------------------------------|----------|----------|----------|----------|----------------|
LOG: Error blah

will hang, but with

LOG: Error blah
...
---------------------------------------------|----------|----------|----------|----------|----------------|
All files                                    |    99.99 |    99.99 |    99.99 |    99.99 |                |
---------------------------------------------|----------|----------|----------|----------|----------------|

it will not…

For us it also seems to specifically hang within gulp, making me suspect that perhaps something is going haywire with the output stream…?

UPDATE & Workaround: waiting for 3 seconds after test suite completion to make sure any async calls that perform console.log execute before the coverage reporter runs successfully gets around the problem.