Refactor type-checking setup

[shadowspawn]

Pull Request

Problem

Type-checking of the JavaScript files using TypeScript was quite fragile and partially misconfigured:

• @ts-check comments were not working to enable checks in JavaScript code in VSCode, as only works on first line
• different settings used by npm run typescript-checkJS than in VSCode so confusing
• npm run typescript-checkJS didn't work on Windows (glob not expanded)

Related: #1960 #1962

Solution

• tsconfig.json with less strict settings covering mixed JavaScript and TypeScript
  • used by VSCode
• tsconfig.ts.json
  • stricter settings
  • just the TypeScript files
  • used by
    • typecheck-ts run-script
    • eslint
    • ts-jest
  • typecheck-ts now included in test run-script for strict checks on the published TypeScript typings
• tsconfig.js.json
  • just the JavaScript files
  • used by typecheck-js.json run-script
• remove glob in run-script so works on Windows
• remove @ts-check comments as JavaScript processing now turned on in tsconfig.json

Explicitly separates the TypeScript and JavaScript files for using with npm run-scripts et al, and run-script naming, following suggestions by @aweebit.

I also updated the lib and module and target settings to match suggested configuration from https://github.com/tsconfig/bases/blob/main/bases/node16.json

References:

• https://www.typescriptlang.org/docs/handbook/intro-to-js-ts.html

ChangeLog

• (dev) improve setup for type-checking of JavaScript files

[aweebit]

Please take a look at my vision for this refactor: shadowspawn/commander.js@feature/type-checking...aweebit:commander.js:feature/type-checking. Explanations are given in the commit descriptions and the comment in jsconfig.json.

You can simply merge my branch into yours if you like the changes.

[aweebit]

Related:

• Glob support for per pattern tsconfig configuration microsoft/TypeScript#21951

[shadowspawn]

Moved to Draft while I have a look at ideas from #1969 (comment)

[shadowspawn]

FYI @aweebit : I was interested in your idea of having extra typings/tsconfig.json to get strict type checking in VSCode for that folder, but it is not supported by tsc and I am not certain it is explicitly supported by VSCode. The wording around tsconfig.json is about the file being in the root of the project, so I kept to an expected layout.

[aweebit]

FYI @aweebit : I was interested in your idea of having extra typings/tsconfig.json to get strict type checking in VSCode for that folder, but it is not supported by tsc

That is why I named the main TSConfig file jsconfig.json instead of tsconfig.json: tsc should not be run without an explicitly specified --project, instead it should ideally be run from npm run typecheck with the right config files.

and I am not certain it is explicitly supported by VSCode.

Not sure what you mean by "explicitly" here, but it is supported. Try this on my branch:

echo 'export let myVar;' > demo.ts
cp demo.ts typings/demo.ts
code demo.ts # no error
code typings/demo.ts # error

[aweebit]

By the way, I used project references to separate configs in #1975. Works really well.

[shadowspawn]

Not sure what you mean by "explicitly" here, but it is supported.

By "explicitly" I mean that it is an intended pattern and not just a happy accident it works. e.g. documented, or used in official examples.

By the way, I used project references to separate configs in #1975. Works really well.

Thanks. I did read about project references, but I did not feel it was a good fit.

[abetomo]

How about typecheck:ts instead of typecheck-ts?
We already use lint:typescript.

[shadowspawn]

I have been following a pattern I saw and liked long ago, but it is arbitrary. I use the colon for sub-scripts which are the parts of a combo script. So lint:typescript is one part of lint.

"lint": "npm run lint:javascript && npm run lint:typescript",

[abetomo]

+1