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Unknown mocha options cause tests to hang

See original GitHub issue

I’m trying to run some code before my tests using the mocha require option, which I thought maybe I could do in the config file as mentioned by https://modern-web.dev/docs/test-runner/test-frameworks/mocha/#configuring-mocha-options.

I’ve found that when I add a require option, my tests just hang and do not execute, eventually timing out. Similarly, if I add a foo option, I get the same thing, whereas another known option like ui: 'tdd' works just fine.

Issue Analytics

State:
Created 2 years ago
Reactions:1
Comments:11 (1 by maintainers)

Top GitHub Comments

1reaction

IanVScommented, May 21, 2021

@EvgeniyLoginov that’s cool. I added a script after my script with src="${testFramework}", and at that point it’s possible to call beforeAll from mocha. I guess either way will work.

0reactions

IanVScommented, May 26, 2021

Oh interesting, I see now why adding rootHooks to the config file doesn’t work. The values there are stringified and added to the window (https://github.com/modernweb-dev/web/blob/6c5893cc79c91e82f9aec35d3011c6e33ce878cc/packages/test-runner-core/src/server/plugins/serveTestRunnerHtmlPlugin.ts#L93), so any functions are lost. That’s unfortunate, since I like the idea of specifying the rootHooks in the config file much better than either of our other approaches.

In the meantime, I’ve switched to using your approach, since it seems to be more reliable with safari. I now have this in my web-test-runner.config file:

module.exports = {
  testRunnerHtml: (testFramework) => `<html>
    <body>
    <script type="module" src="/test-setup/globals.js"></script>
    <script type="module" src="/test-setup/mocha-hooks.js"></script>
    <script id='uit' type="module" src="${testFramework}"></script>
    </body>
  </html>`,
  testFramework: {
    config: {
      rootHooks: {
        // We can't actually add them here, since WTR serializes this config to a string.
        // But we can create the structure and then modify it in our mocha-hooks.js file
      },
    },
  },
};

And then in mocha-hooks.js:

// HACK:  WTR serializes the config to a string, so we can't define our hooks in
// web-test-runner.config.cjs.  Instead, we'll modify it from the global window here.
(window as any).__WTR_CONFIG__.testFrameworkConfig.rootHooks = {
  afterEach() {
    cleanup();
  },
};