🚀 Feature: Require schema to be present

[DaniFoldi]

Bug Report Checklist

• I have tried restarting my IDE and the issue persists.
• I have pulled the latest main branch of the repository.
• I have searched for related issues and found none that matched my issue.

Overview

Hi 👋,

While this tool does a pretty good job of keeping package.json free of typos by validating the contents, for manual editing a $schema is sometimes useful. Most of my package.json files contain a "$schema": "https://json.schemastore.org/package.json", line so that they can be validated in CI. What do you think about adding a rule that adds $schema to package.json?

Additional Info

No response

[michaelfaith]

Seems reasonable to have that as a new rule available for people to opt into, but not included in the recommended config. If we're going to include a fixer that adds it, then probably should have the schema url be configurable. Though our other require-x rules don't have fixers that add anything...
Thoughts?

[DaniFoldi]

Thanks for the quick response!

I think it makes sense to have it opt-in, quite possibly some people don’t want the schema to be declared in the file.

Looking at the autofix, it’s definitely a more special case as the autofix in other ones doesn’t make much sense, but here the value could be “fixed”, although I don’t see why a config couldn’t contain a rule for requiring a specific license, perhaps in a monorepo. Following this chain of thought, I would definitely make it configurable.

[michaelfaith]

@JoshuaKGoldberg curious about your thoughts. In general, but especially on the issue of having a fixer for this, since we have traditionally kept the require- flavor of rules purely focused on "does this thing exist or not", rather than having any say about the value of the property. (though, as I type that out, perhaps the validation doesn't check the value, but if we populate a missing value with a fixer, then we could populate it with a particular schema value...)

[JoshuaKGoldberg]

🤔 I'm not convinced this is a common or necessary enough practice to justify including in this package.

"Common": This Sourcegraph search for the schemastore string in package.json files shows 292 results right now. That's a teeny fraction of a teeny fraction of the 1.4+ million package.json files Sourcegraph can find.

"Necessary": As I understand it, there are two benefits:

• Editor intellisense/suggestions: i.e. showing dropdowns
  • This is provided by default for package.json files in most common editors, including Webstorm and VS Code
• Validation: what is already provided by this package's require-* and valid-* rules
  • If anything is validated by the JSON schema but not by the other rules, I'd think that a bug in the rules

-1 from me right now, but I'm open to being convinced. What real benefits are there for many users from including a $schema property in a package.json file?