Invalid name of some module in production mode

[bupy7]

Bug report

What is the current behavior?

Sometimes without any reasons my project do not works properly in production mode. If I build up my project in development mode - everything is perfect, no any errors. But in production mode I have some weird problem.

Sometimes after build up I see an error like this in the Developer Console:

As you see, the d8498 is not defined. I have looked into the file 286_6660b.js and saw this:

/* harmony import */ var _code_editor__WEBPACK_IMPORTED_MODULE_5__ = __webpack_require__(d8498);

The name of module just not in enclosed quotes, because d8498 is not valid name for this situation. And if I fix this name adding enclosed quotes the error is gone. And it's not the most weird. I'v found the component of the module code_editor and just renamed the directory code-editor adding _ in the beginning of name to make it _code-editor. After it the error is gone too. Very weird.

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

I don't know how to reproduce it, because it has periodic character. Sometimes I fix with renaming files/directories, sometimes deleting JSDoc tags. It always the same error regardless to whether use minimization in Webpack.

What is the expected behavior?

I expect a valid number name for all modules after building in production mode.

Other relevant information:
webpack version: 5.75
Node.js version: 16.13.2
Operating System: Linux Debian 10 Buster

[alexander-akait]

As you can see this error from the browser extension, sounds like you have race condition somewhere, we need as minimum reproducible test repo, otherwise we really can't help you, can you provode your configuration?

[bupy7]

I'v sent you my configuration of Webpack above.

[alexander-akait]

Can you change [contenthash:5] to [contenthash:8]? 5 is very small, you can have overlapping

[bupy7]

Yeap! It's looking like fixed my problem. Thanks a lot!

[alexander-akait]

When you use very small value (for example 3 you can overlap your hashes with numbers (for example - 100, is it number in code or hash?), I recommend to use 8 as minimum to avoid collisions)

[bupy7]

I see. Thanks! Although "8" do not give 100% guarantees either. But now I know where problem is.

[phoenixinwater]

Hi @alexander-akait I have also experienced this issue but the offending hash for me is the same as the MiniCssExtractPlugin output contenthash. Would you be able to point to me where in the src, if it is possible, where a conflict between module IDs and loader output hashes could occur? The module IDs are all numeric on init but at some point in the build, that I am struggling to find, one is replaced with a non-numeric hash. Example of 'bad' hashes are 09e92 and 9b802 for css file contenthash length of 4.

[alexander-akait]

@phoenixinwater Sorry for delay, is it still valid?