Error: You need to include some adapter that implements __karma__.start method

Question

I'm trying to add some unit tests to one of my projects.

So far I've installed and configured karma, and have installed jasmine. I've one test file in my test/ folder.

The karma server has started, the browser page is ready, but karma run fails as follows:

$ karma run karma-conf.js 
[2014-06-14 15:19:11.046] [DEBUG] config - Loading config /foo/test/karma-conf.js
Waiting for previous execution...
Chrome 35.0.1916 (Linux) ERROR
  You need to include some adapter that implements __karma__.start method!

This error message doesn't Google well.

Is this something obvious, or do I need to provide more information?

Answer 1

It does seem like this is a very general error, however in my case the problem was either that I didn't run karma start from the correct folder, or that I didn't restart it after changing the configuration.

I'll leave this question open and hopefully it can become a resource for others who experience this error message.

Answer 2

If you name your karma config file karma.conf.js, you can simply type karma start.

Otherwise specify the filename karma start karmafile.js

(I was in the right directory, but was not specifying a file name.)

Answer 3

You need to run your karma run or whatever function in the folder where karma-conf.js is in.

Answer 4

In my case I had to rename the file to karma.conf.js then do karma start

Answer 5

I had a problem with karma.conf.js file code format:

files: [
    // Modules
    ,"client/bower_components/angular/angular.min.js"
    ,"client/bower_components/angular-mocks/angular-mocks.js"
    // App
    ,"client/app/app.module.js"
    // Test
    // ,"test/**/*.spec.js"
],

The extra comma in files array have cause this error:

You need to include some adapter that implements __karma__.start method!

Answer 6

I was not running karma start command from the path where my karma.conf.js was. I switched to that folder and ran the same command. Thats all

Answer 7

I was facing this issue while running specs on the Angular.js codebase. I had to run npm install karma-jasmine -g to get this working.

Answer 8

If you typing "karma start", you must have a karma.conf.js file in the current folder. or just "karma start /path/karma.conf.js"

Try to create a new karmar.conf.js by "karma init /path/karma.conf.js"

Answer 9

In my case, I was applying by mistake the commonjs preprocessor to the karma-* modules and the adapter.js from karma-chrome and karma-firefox was broken this way.

Unfortunately, this is a very generic error.

Answer 10

I was getting the same error because the project was using Babel 6 and I had forgotten to add the babelrc file. Just sharing in case this could help.

Answer 11

In my case, the message was in fact very descriptive: I forgot to add an adapter, in my case Jasmine, into the config file. Thus:

module.exports = function(config) {
  config.set({
      browsers: ['Chrome'],
      singleRun: true,
      frameworks: ['jasmine'],
      files: [
          // ... files ...
      ],
      // other configs
    });
};

Answer 12

You need to configure your "my.conf.js" file, because it contains all the info to use to test your code.

All what you need to write is this:

The configuration file can be generated using karma init:

$ karma init my.conf.js

Which testing framework do you want to use? Press tab to list possible options. Enter to move to the next question.

jasmine

Do you want to use Require.js? This will add Require.js plugin. Press tab to list possible options. Enter to move to the next question.

no

Do you want to capture a browser automatically? Press tab to list possible options. Enter empty string to move to the next question.

Chrome

What is the location of your source and test files? You can use glob patterns, eg. "js/*.js" or "test/**/*Spec.js". Press Enter to move to the next question.

*.js test/**/*.js

Should any of the files included by the previous patterns be excluded? You can use glob patterns, eg. "**/*.swp".

Press Enter to move to the next question.

Do you want Karma to watch all the files and run the tests on change? Press tab to list possible options.

yes

Config file generated at "/Users/vojta/Code/karma/my.conf.js".

Answer 13

You must specify the karma configuration file to karma.

karma start karma.config.js 

It works for me

Answer 14

I must add that in my case karma was giving me the error because I had [square] brackets in the name of one of the parent folders.

Answer 15

In my case, it was not karma-related at all! I run karma from gulp, with ES6/babel, and there was actually a code syntax error, flagged by a babel error above my karma:

ERROR [preprocessor.babel]: xxx.js: Unexpected token (19:83)

I fixed that in my src and karma was happy again.

Answer 16

Tt's complaining about the adapter which is probably jasmine or mocha. Either the adapter is missing, either is not setup correctly, either it's an outdated or buggy version of the adapter.

In my case I had an old version of mocha 2.5.3 which was not compatible with karma 1+. I updated the mocha dependency to the latest version available 3.2.0 and the problem solved.

Answer 17

While working on numerous vaguely described errors, I tried setting basePath: '../', After correcting other errors (like missing commas that were described as object content errors) the last change back to basePath: '', got karma to work. karma's error statements need a lot of work. It is not simple to get it going.

Answer 18

I had the same issue. My browser would open but on my terminal it threw the following error

30 08 2017 11:19:28.272:INFO [Chrome 58.0.3029 (Linux 0.0.0)]: Connected `enter code here`on socket 5sSs6E5KmpUVRp6LAAAB with id 93886631
Chrome 58.0.3029 (Linux 0.0.0) ERRORSome of your tests did a full page reload!

I checked my karma.conf.js file. In the framework array , i had included jasmine and requirejs. But i had only installed karma-jasmine.Removing requireJS and rerunning the karma start worked!

Answer 19

I've been struggling with this too. What I came up to is that this error occurs because one of the following reasons

• No test adapter installed or defined (frameworks property in karma.conf.js
• No karma configuration found (ie, no karma.conf.js in current dir or no config file specified in command)

My problem was that my config file was named karma.config.js instead of karma.conf.js.

If you've installed the test adapter but it still doesn't work, try running karma init and go through the guided config setup.

Answer 20

You will have to specify the directory of karma.config.js when you run start karma.

Try

karma start karma.config.js

Answer 21

I had a bad 'files' configuration in my karma.conf.js

files: ['**/*.js'],

this caught up all the files in node_modules/ including those of the karma-jasmine plugin, as it was seen as sourde files it wasn't loaded on startup. Changing to

files: [
        'src/*.js',
        'spec/*.js'
    ],

solved the problem in my case

Answer 22

FWIW - sourcing the file path of karma.conf.js worked for me locally, but not on my jenkins builder. I have zero clue why this is the case, but on jenkins it was throwing this error unless the karma.conf.js file was in the root directory where the karma command was given. I'm using rails and running the js specs through a rake task. Code is below which might be helpful for some.

https://gist.github.com/daino3/a39486ff8bfc1668e923

Answer 23

The issue in my case was that karma didn't pick up any files. Fixing it in karma.conf.js solved the issue.

Answer 24

Same issue happened to me, and it was due to an outdated module.

Running npm update solved it.

Answer 25

In my case, the configuration file name was different. So, running the command specifying the conf file solved my issue.

>> karma start unit-tests.conf.js
No captured browser, open http://localhost:9876/
...

And for 'PhantomJS', opening the link specified(localhost:9876) in the browser executes the test cases.

Hope it helps. :)

EDIT 1: My Karma Config File

module.exports = function(config) {
  config.set({

    // base path that will be used to resolve all patterns (eg. files, exclude)
    basePath: '',


    // frameworks to use
    // available frameworks: https://npmjs.org/browse/keyword/karma-adapter
    frameworks: ['jasmine'],


    // list of files / patterns to load in the browser
    files: [
      './node_modules/angular/angular.js',
      './node_modules/angular-ui-router/release/angular-ui-router.js',
      './node_modules/angular-mocks/angular-mocks.js',
      './app/services/users/users.js',
      './app/app.js',
      './app/services/users/users.spec.js'
    ],


    // list of files to exclude
    exclude: [
    ],


    // preprocess matching files before serving them to the browser
    // available preprocessors: https://npmjs.org/browse/keyword/karma-preprocessor
    preprocessors: {
    },


    // test results reporter to use
    // possible values: 'dots', 'progress'
    // available reporters: https://npmjs.org/browse/keyword/karma-reporter
    reporters: ['spec'],


    // web server port
    port: 9876,


    // enable / disable colors in the output (reporters and logs)
    colors: true,


    // level of logging
    // possible values: config.LOG_DISABLE || config.LOG_ERROR || config.LOG_WARN || config.LOG_INFO || config.LOG_DEBUG
    logLevel: config.LOG_INFO,


    // enable / disable watching file and executing tests whenever any file changes
    autoWatch: true,


    // start these browsers
    // available browser launchers: https://npmjs.org/browse/keyword/karma-launcher
    browsers: ['Chrome'],


    // Continuous Integration mode
    // if true, Karma captures browsers, runs the tests and exits
    singleRun: false,

    // Concurrency level
    // how many browser should be started simultaneous
    concurrency: Infinity
  })
}

Answer 26

I received this error because I required the same dependency twice!

Removing the duplicate file dependency removed the error for me. Circled in blue below.

Answer 27

Given this is the first result on google for this error message, I figured I'd mention my resolution here.

I was getting this error after converting an AngularJS 1.8 project to Typescript and trying to change over my Karma tests to use the typescript preprocessor.

I finally realized that adding import angular from 'angular' resolved the issue on Karma's side, but then angular turned up as undefined in webpack's build.

Eventually thanks to this answer on a question about that error message, I updated my import statements to import * as angular from 'angular', and finally it worked! (Ultimately I had to resolve every compilation error on every typescript file for complete resolution, which I had been somewhat ignoring since the webpack build worked.)

Hopefully this can help someone with this problem!

Answer 28

I had the same problem but above mentioned solutions didn't work for me. What I eventually found out is that my karmaWebpackConfig was using "babel-loader" as loader. I just removed that line and it worked for me.

Answer 29

I am using karma-typescript and after searching for a long time i finally thought about looking into the Browser-Console and i saw the error:

876/context.html:1 Refused to execute script from '....ts'
because its MIME type ('video/mp2t') is not executable.

As it turns out... Karma is using a package 'mime' to check if the script is exectuable and it assumes that .ts is the .ts-Videoformat and not typescript.

To fix this issue you need to add the following to your karma.conf.js:

mime: {
        "text/x-typescript": ["ts","tsx"]
      }