Add deprecated flag warning to build

[cartogram]

WHY are these changes introduced?

This PR adds a helper that we can add to the commands whose flags have changed from going from v1 to v2. Currently the CLI will fail if an unsupported flag is passed without much indication of why. For example:

I saw the above example come up in Discord.

WHAT is this pull request doing?

There are a few ways we can address this, but I chose to create a small helper we can add to the Command's flag object. In this PR I've added it to some of the deprecated build flags.

HOW to test your changes?

Run the CLI locally with a flag from H1 (ie: --entry).

Post-merge steps

Checklist

• I've read the Contributing Guidelines
• I've considered possible cross-platform impacts (Mac, Linux, Windows)
• I've added a changeset if this PR contains user-facing or noteworthy changes
• I've added tests to cover my changes

[cartogram]

This solution forces the banners to render individually, if we wanted a different experience, we might want to add a catch to the command. For example:

const DEPRECATED_FLAGS = [...]

 async catch(error: Error & {args?: string[]}) {
   if (error?.args?.some((flag) => DEPRECATED_FLAGS.includes(flag))) {
      renderInfo({
        headline: `The ${colors.bold(
          error.args.join(' '),
        )} flags are deprecated and will be removed in a future version of Shopify CLI.`,
      });

    throw error;
  }

My feeling is that 90% of the time users will hit this error when moving from H1 to H2 and not updating the build script in their package json (which has a --entry flag).

[frandiox]

Great idea!

Can we add this to the dev command as well for the --entry flag?

I think it's fine if we render the banners separately, it's just a warning that shouldn't come up often.

[lordofthecactus]

✅

[cartogram]

@pepicrft @matteodepalo maybe something like this should make it's way into the cli-kit 🤔 I could see this being a common pattern.

[matteodepalo]

Interesting! Definitely something that we could add to cli-kit.