[CLI] Fix issues with StyleX usage within external packages

[nmn]

At it's core, the CLI transforms an entire folder to to transform the JS and extract the CSS. This works well.

You can also manually declare external package dependencies that should be pre-compiled. However, this process is somewhat buggy today.

The task is to fix the problems with pre-compiling external packages.

Details of the task

The CLI lets you define specific packages that should be compiled with StyleX. It is important these packages are not pre-compiled and should only have source files and not compiled files.

The CLI pre-compiles the configured packages into the output folder.

• Investigate the limitations of the current approach
• Investigate why the packages are sometimes not compiled correctly on edits. This is specially relevant to monorepos.
• Fix the bugs to ensure that the CLI reliably compiles configured packages.
• Ensure that changes in mono-repo packages are tracked and the files re-compiled on edits

[sudheerDev]

Hey, @nmn Can I pick this up?

[nmn]

@sudheerDev You're welcome to.

[devhd9]

@nmn, It's been a while so I'm assuming @sudheerDev is not currently working on this.

I would like to take up this issue and work on fixing the CLI's handling of pre-compiling external package dependencies. Could you please share more details about the specific bugs or challenges currently being faced during this process?

Additionally, it would be helpful if you could elaborate (or share any relevant resources) on the primary goals or motivations for pre-compiling external package dependencies.

Thanks.

[nmn]

@devhd9 You can work on it. Note: we want to start sharing code between the CLI and the postcss-plugin going forward so please try to make sure your code is not tightly coupled to the CLI.

[devhd9]

we want to start sharing code between the CLI and the postcss-plugin going forward so please try to make sure your code is not tightly coupled to the CLI.

Sure, I will keep this in mind.

Can you please also give me clarity on following?

the specific bugs or challenges currently being faced during this process?

Additionally, it would be helpful if you could elaborate (or share any relevant resources) on the primary goals or motivations for pre-compiling external package dependencies.

[nmn]

@devhd9 I wrote down more details above. Lmk, if there's anything I else I should elaborate on.

the primary goals or motivations for pre-compiling external package dependencies.

The goal is to allow you to use external packages that use stylex within. e.g. component library packages.

[Jta26]

Thought I'd chime in on this one as the CLI's original creator to give you some additional context.

Currently the CLI does 2 main functions with regard to external packages prior to compiling the input directories.

1. Temporarily copies them to the input directory
2. rewrites the import declarations to reference the newly copied version

I originally attempted to do it by just rewriting imports and copying them directly to the output directory, however when StyleX compiled this way the hashes it compiled to were incorrect because I'm pretty sure it uses the import declaration and source directory to create the CSS var hashes.

Most of the issues probably lie in the fact that it is copying (and then deleting post-compile) the external packages to the input directory, but there is probably other reasons too. I think a lot of the issues are specifically with running the CLI in watch mode, which might be fixable by moving the CLI off of node-watchman and to something like chokidar.

Also, the CLI really needs some more tests, but that can be a separate issue

[devhd9]

Thanks @nmn and @Jta26, I appreciate your input.