Create @shopify/polaris-migrator package

[sam-b-rose]

Adds the beginnings of the @shopify/polaris-migrator package. This package applies code transformations to help update
Polaris apps and the Polaris codebase.

Usage

npx @shopify/polaris-migrator <migration> <path>

Run tests for @shopify/polaris-migrator

yarn test --filter=@shopify/polaris-migrator 

[sam-b-rose]

/snapit

[github-actions]

🫰✨ Thanks @samrose3! Your snapshots have been published to npm.

Test the snapshots by updating your package.json with the newly published versions:

yarn add @shopify/[email protected]

yarn add @shopify/[email protected]

[sam-b-rose]

/snapit

[github-actions]

🫰✨ Thanks @samrose3! Your snapshots have been published to npm.

Test the snapshots by updating your package.json with the newly published versions:

yarn add @shopify/[email protected]

yarn add @shopify/[email protected]

[BPScott]

Heck yeah I love me some codemods!

Dropped some comments around the place. Noteably I think it'd be very valuable to use postcss-value-parser to get a better AST for handling transforms of prop values.

[BPScott]

I'm not a fan of the usage of regex here. It looks like it can match false positives like my-spacing(), and miss variations in whitespace/quoting like spacing( none ), spacing('none') and spacing( "none" ) (admittedly as we use prettier our whitespace should be pretty conventional so this shouldn't be a huuuge issue for our codebases).

I'd expect us to have a better AST here. There should be AST nodes for stuff like "this is a function with a name and these specific arguments" - you should be able to be able to say "only act when you find a function name, whose name is "spacing" and has these specific values as the first argument". We should leverage a tokeniser, rather than trying to fuzzy match ourselves. It looks like this behaviour of transforming values into "this is a function call" etc is provided by postcss-value-parser

stylelint has a demo of using postcss-value-parser https://github.com/stylelint/stylelint/blob/main/lib/rules/function-allowed-list/index.js#L36

[sam-b-rose]

Closing in favor of new iteration in #6852