webpack compiling twice on startup when importing a file within a typescript react setup

[bahtou]

Bug report

What is the current behavior?

Working on a TypeScript React project when running webpack the compilation happens twice at startup. This happens when a file is being imported from the root react index.tsx.
Not sure if its similar to #13618?

If the current behavior is a bug, please provide the steps to reproduce.

1. https://github.com/bahtou/issues/tree/webpack-rebuild
2. follow the readme

you should be able to see two rebuilds

👀   1 . compilation afterEmit 2021-11-18T22:01:58.573Z
👀   1 . compilation is done 2021-11-18T22:01:58.575Z

👀   2 . compilation afterEmit 2021-11-18T22:01:58.872Z
👀   2 . compilation is done 2021-11-18T22:01:58.872Z

What is the expected behavior?

compilation should only run once

Other relevant information:
webpack version: 5.64.1
Node.js version: v14.18.1
Operating System: OSX
Additional tools: none

[markjm]

I think this is related to #14735.

The invalidation comes from

_invalidate(..., ..., Set(0) {} Set(2) {
  '/workspaces/issues/node_modules/package.json/package.json',
  '/workspaces/issues/node_modules/swc-loader.js/package.json'
}

This indicated that watchpack.watch is called with these invalid file entries. When encountering these paths, it then tries to adds watchers for these files, fails (because they dont exist "initial-missing / scan (parent directory missing in initial scan)") and marks them as removed.

[wood1986]

I think it has nothing with TS. My JS repo has the same issue and it compile 3 times.
I can 120% confirm 5.64.0 work fine and it only happen at 5.64.1

[bahtou]

@wood1986 I switched to webpack v5.64.0 and I still get the double compilation. With the repo above you can test it out. Agree that it has nothing to do with TS. The webpack config is not using TS for anything. I just mentioned it since I was setting up a new project.

[alexander-akait]

Yep, it is bug

[alexander-akait]

@bahtou v5.64.0 doesn't have this problem, just tested on your repo

[bahtou]

@alexander-akait I just cloned the repo and updated the webpack package to 5.64.0.
I'm still getting double compilation 🤔 🤔

rm -rf node_modules package-lock.json
npm install
npm start

UPDATE
"webpack": "^5.64.0", the caret ^ was throwing me off. Removing the ^.

v5.64.0 DOES NOT have the issue. 👍🏽

[alexander-akait]

Yep...

[sokra]

should be fixed by https://github.com/webpack/webpack/releases/tag/v5.64.2