Repo: v6 branch regression for adding to JSX.IntrinsicAttributes in typecheck task

[JoshuaKGoldberg]

Suggestion

On the v6 branch, we now get typecheck (tsc) complaints in ast-spec's fixture for augmenting JSX.IntrinsicElements:

 ~/repos/typescript-eslint/packages/ast-spec $ yarn typecheck
yarn run v1.22.19
$ tsc -p tsconfig.json --noEmit
src/jsx/JSXNamespacedName/fixtures/component-dashed/fixture.tsx:8:24 - error TS2339: Property 'foo' does not exist on type 'JSX.IntrinsicElements'.

8 const componentBasic = <foo />;
                         ~~~~~~~

src/jsx/JSXNamespacedName/fixtures/component-dashed/fixture.tsx:9:25 - error TS2339: Property 'foo-bar:baz-bam' does not exist on type 'JSX.IntrinsicElements'.

9 const componentDashed = <foo-bar:baz-bam />;
                          ~~~~~~~~~~~~~~~~~~~


Found 2 errors in the same file, starting at: src/jsx/JSXNamespacedName/fixtures/component-dashed/fixture.tsx:8

It happens both for traditional names (e.g. foo) and for TypeScript 5.1's new namespaced names (e.g. 'foo-bar:baz-bam') added in #7088. So I don't think it's specific to TS 5.1's namespace changes.

But... why is this happening? Why is the fixture not allowing augmentation of JSX.IntrinsicElements?

I'm 80% confident this is a silly little mistake I made in merging main -> v6, but can't figure it out... :sob

[JoshuaKGoldberg]

I // @ts-expect-error'd the build breakage away, but we should really investigate this. 41d68ea

[armano2]

@JoshuaKGoldberg currently only ts file extensions are excluded from typechecking

typescript-eslint/packages/ast-spec/tsconfig.json

Line 8 in d2973cc

"exclude": ["**/fixtures/**/fixture.ts"],

-  "exclude": ["**/fixtures/**/fixture.ts"],
+  "exclude": ["**/fixtures/**/fixture.ts", "**/fixtures/**/fixture.tsx"],

alternatively you can addmissing declare global

typescript-eslint/packages/ast-spec/src/jsx/JSXNamespacedName/fixtures/component-dashed/fixture.tsx

Lines 1 to 6 in d2973cc

	declare namespace JSX {
	interface IntrinsicElements {
	foo: any;
	'foo-bar:baz-bam': any;
	}
	}

+ declare global {
+ namespace JSX {
- declare namespace JSX {
    interface IntrinsicElements {
      foo: any;
      'foo-bar:baz-bam': any;
    }
  }
+ }