Adding JavaScript functions to sample apps

[nickwesselman]

Existing sample apps can add JavaScript functions in this PR. It should not be merged until JavaScript functions are generally available.

• Vanilla JavaScript functions should be added side-by-side with existing Rust functions to all sample apps.
• The function logic should be the same in JS as it is in Rust.
• Vitest should be used to exhibit unit testing.
• Test cases should be the same in JS as they are in Rust.

🎩

• Execution of JS functions requires the checkout extensibility developer preview.

Payment Customization

yarn create @shopify/app --template https://github.com/Shopify/function-examples/sample-apps/payment-customizations#sample-apps-javascript

Delivery Customization

yarn create @shopify/app --template https://github.com/Shopify/function-examples/sample-apps/delivery-customizations#sample-apps-javascript

Discounts

yarn create @shopify/app --template https://github.com/Shopify/function-examples/sample-apps/discounts#sample-apps-javascript

[andrewhassan]

Out of curiosity, why did we choose to have a JS example and not a TS example instead?

[andrewhassan]

Should these two yarn.lock files be committed? It looks like we already have package-lock.json files. We should choose one or the other depending on the tooling we recommend (e.g. yarn or npm).

[nickwesselman]

I thought we had standardized on yarn in this repo, but looks like we have a mix. In our docs, we don't recommend a particular package manager. But the CLI team internally has moved from yarn to pnpm.

[nickwesselman]

Out of curiosity, why did we choose to have a JS example and not a TS example instead?

@andrewhassan Our docs, and thus the sample, are going to focus on JS based on consistency with UI extensions, and survey feedback (Vanilla JS edging out TS). Thought about doing both but it would add maintenance overhead for minor benefit.

[nickwesselman]

@adampetro Looks like this is failing now due to Rust checks being done on a JavaScript extension, is that something that was added in the JS unit test PR?

[adampetro]

@adampetro Looks like this is failing now due to Rust checks being done on a JavaScript extension, is that something that was added in the JS unit test PR?

Most likely this line. I think we can get around it by using exclude in the root Cargo.toml.

[nickwesselman]

@adampetro Thanks! Unfortunately they can't be globbed due to this but that fixed it.

Also added the JS sample extensions to the workspace so those tests run now too. Awesome work setting up all the test automation.

[adampetro]

Looks great! If you have time it would be nice to add a newline at the end of files that don't have one