Types should be defined in .ts files

[maxpatiiuk]

Check existing issues

• I have checked for existing issues to avoid duplicates

Actual Behavior

Calcite has a number of .d.ts files that include public-facing types:
https://github.com/Esri/calcite-design-system/blob/dev/packages/calcite-components/src/components/handle/interfaces.d.ts

Usually, .d.ts files should not be authored by hand - the only case they are authored by hand is when you need to provide types for a library that is missing them - and such types would be used for internal type checking only.

To that end, tsc by default does not copy the hand-authored .d.ts files to the build output. Lumina follows this behavior. It appears than in Stencil, hand-authored .d.ts files were being copied too.

This is causing errors when type-checking JS API as interfaced.d.ts files are missing from public typings.

side note: it appears that not all Calcites interfaces files are using .d.ts - some use .ts and correctly appar in the build output:
https://github.com/Esri/calcite-design-system/blob/dev/packages/calcite-components/src/components/accordion-item/interfaces.ts

Expected Behavior

All files that include public-facing types should use .ts files

Reproduction Sample

npx tsc --outDir types --emitDeclarationOnly --declaration

Reproduction Steps

Run this from packages/calcite-components

npx tsc --outDir types --emitDeclarationOnly --declaration

See that hand-authored .d.ts files don't appear in the output, but .ts files do. Lumina has the same behavior since it's using TypeScript API behind the scenes

Reproduction Version

3.0.0-next.16

Relevant Info

No response

Regression?

No response

Priority impact

impact - p1 - need for current milestone

Impact

Breaks JS API type checking:

node_modules/@esri/calcite-components/dist/components/calcite-handle/customElement.d.ts:5:43 - error TS2307: Cannot find module './interfaces' or its corresponding type declarations.

5 import { HandleChange, HandleNudge } from './interfaces';
                                            ~~~~~~~~~~~~~~
node_modules/@esri/calcite-components/dist/components/calcite-input-time-zone/customElement.d.ts:11:43 - error TS2307: Cannot find module './interfaces' or its corresponding type declarations.

11 import { OffsetStyle, TimeZoneMode } from './interfaces';
                                             ~~~~~~~~~~~~~~
node_modules/@esri/calcite-components/dist/components/calcite-shell-panel/customElement.d.ts:4:29 - error TS2307: Cannot find module './interfaces' or its corresponding type declarations.

4 import { DisplayMode } from './interfaces';
...

Calcite package

• @esri/calcite-components
• @esri/calcite-components-react
• @esri/calcite-design-tokens
• @esri/calcite-ui-icons
• @esri/eslint-plugin-calcite-components

Esri team

ArcGIS Maps SDK for JavaScript

[maxpatiiuk]

side note: we could include some sort of warning for this in Lumina.
However, there would likely be many false positives since there are valid use cases for hand-authoring .d.ts files - for providing internal typings when consuming libraries that are authored as .js only.

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[DitwanP]

🍡 Verified