Must restart Cypress to run newly added spec file when using Webpack 5

[lmiller1990]

Current behavior

If you add a new spec file after starting the component testing runner, eg touch src/MySpec.spec.jsx, it shows up in the runner, but it always says "no test found", even if you add some tests to the spec file.

You need to restart the runner to webpack to start watching the file correctly.

It only happens for projects using Webpack 5.

Desired behavior

Should work like it does for Webpack 4. I don't want to restart the runner.

Test code to reproduce

• Get any webpack 5 repo, for example this one https://github.com/lmiller1990/cypress-react-webpack-5-example
• yarn cypress open-ct
• touch src/Blah.spec.jsx
• Click Blah.spec.jsx in the side bar
• Notice "no tests found"
• add a test, eg it('something', () => {})
• observe webpack does not notice the file changed or rebundle it

Versions

• cypress 7.4.0
• latest cypress/webpack-dev-server
• webpack 5.x
• webpack dev server, probably 3.x

[lmiller1990]

After much investigation I am fairly sure the problem is this line is not doing what it does with Webpack 4.

I don't know how to fix it yet, though, or what changed - this is not even a documented part of Webpack.

[cypress-bot]

The code for this is done in cypress-io/cypress#17950, but has yet to be released.
We'll update this issue and reference the changelog when it's released.

[lmiller1990]

#17950 fixes it!

[emilyrohrbough]

This was released as @cypress/webpack-dev-server v1.8.1 on Feb 10, 2022

[cypress-bot]

Released in 10.0.0.

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Cypress v10.0.0, please open a new issue.