Karma: Karma 4.0.1 fails with unexpected identifier 'async'

[ronakjain90]

Expected behaviour

karma 4.0.1 to start the test and successfully test out the specs. While it works fine locally (osx), for some reason it's failing in CI environment.

Actual behaviour

#!/bin/bash -eo pipefail
cd spec_js
if [ "$CIRCLE_NODE_INDEX" -eq 2 ]; then npm install && npm run test-ci; fi
npm notice created a lockfile as package-lock.json. You should commit this file.
npm WARN [email protected] No repository field.
npm WARN [email protected] No license field.
npm WARN optional SKIPPING OPTIONAL DEPENDENCY: [email protected] (node_modules/fsevents):
npm WARN notsup SKIPPING OPTIONAL DEPENDENCY: Unsupported platform for [email protected]: wanted {"os":"darwin","arch":"any"} (current: {"os":"linux","arch":"x64"})

added 372 packages in 10.533s

> [email protected] test-ci /home/circleci/project/spec_js
> ./node_modules/karma/bin/karma start ./karma.conf.js

/home/circleci/project/spec_js/node_modules/karma/lib/server.js:118
async start () {
^^^^^
SyntaxError: Unexpected identifier
at exports.runInThisContext (vm.js:53:16)
at Module._compile (module.js:511:25)
at Object.Module._extensions..js (module.js:550:10)
at Module.load (module.js:456:32)
at tryModuleLoad (module.js:415:12)
at Function.Module._load (module.js:407:3)
at Module.require (module.js:466:17)
at require (internal/module.js:20:19)
at Object.<anonymous> (/home/circleci/project/spec_js/node_modules/karma/lib/cli.js:8:16)
at Module._compile (module.js:541:32)
npm ERR! code ELIFECYCLE
npm ERR! errno 1
npm ERR! [email protected] test-ci: `./node_modules/karma/bin/karma start ./karma.conf.js`
npm ERR! Exit status 1
npm ERR!
npm ERR! Failed at the [email protected] test-ci script.
npm ERR! This is probably not a problem with npm. There is likely additional logging output above.

npm ERR! A complete log of this run can be found in:
npm ERR!     /home/circleci/.npm/_logs/2019-03-15T05_32_20_835Z-debug.log
Exited with code 1

Environment Details

• Node v11.6.0 (npm v6.5.0-next.0)
• Karma - 4.0.1
• Relevant part of your karma.config.js file

/// karma.conf.js
module.exports = function (config) {
  config.set({
    basePath: '',
    frameworks: ['mocha', 'chai', 'sinon'],
    plugins: [
      'karma-chrome-launcher',
      'karma-mocha',
      'karma-chai',
      'karma-sinon',
      'karma-string-replace-preprocessor'
    ],
    files: [
      'jquery.js',
      '../pages.js',
      'pages-spec.js'
    ],
    exclude: [],
    preprocessors: {
      '../pages.js': ['stringreplace']
    },
    stringReplacePreprocessor: {
      patterns: [
        { match: 'process.env.HOST', replacement: '"https://www.host.com"' },
      ]
    },
    reporters: ['progress'],
    port: 9876,
    colors: true,
    logLevel: config.LOG_INFO,
    autoWatch: false,
    browsers: ['Chrome'],
    singleRun: true
  });
};

[johnjbarton]

The most likely explanation is that your CircleCI is running node < 6.

[ronakjain90]

I had that reasoning too. but I get this while debugging.

#!/bin/bash -eo pipefail
export NVM_DIR="/opt/circleci/.nvm"
[ -s "$NVM_DIR/nvm.sh" ] && \. "$NVM_DIR/nvm.sh"
nvm install v11.6.0
nvm alias default v11.6.0
npm -v
Downloading https://nodejs.org/dist/v11.6.0/node-v11.6.0-linux-x64.tar.xz...

######################################################################## 100.0%
Now using node v11.6.0 (npm v6.5.0-next.0)
default -> v11.6.0
6.5.0-next.0

[johnjbarton]

Try putting this in your karma.config.js

console.log(`Version: ${process.version}`);

Or even better open /home/circleci/project/spec_js/node_modules/karma/lib/server.js:118 and put the log there.

[yrtimiD]

I have a latest 6.x node (6.17.0) and get exactly same error.

[johnjbarton]

@yrtimiD Use karma 3.x for node 6.x.

[ronakjain90]

Closing this issue, since for some reason Circle CI wasn't using the desired node version. Can confirm that it's a node 6.x issue. Thanks a lot for responding.

[Mifrill]

to resolve: yarn add [email protected]