[question] How to use platform specific code in libs?

It's me again :)

This time it's a question on how to do platform specific code in the libs. Here's my current issue:

I have these files under libs/nativescript-utils:

• src/lib/nativescript-utils.d.ts
  • export function nativescriptUtils(): string;
• src/lib/nativescript-utils.android.ts
• src/lib/nativescript-utils.ios.ts
• src/index.ts
  • export * from './lib/nativescript-utils';

Then I import the nativescriptUtils() in the app. When running the app I get this error:

ERROR in ../../libs/nativescript-utils/src/lib/nativescript-utils.ios.ts
Module build failed (from ../../node_modules/@ngtools/webpack/src/index.js):
Error: /Users/frank/git/private/nx-mobile-test/libs/nativescript-utils/src/lib/nativescript-utils.ios.ts is missing from the TypeScript compilation. Please make sure it is in your tsconfig via the 'files' or 'include' property.
    at /Users/frank/git/private/nx-mobile-test/node_modules/@ngtools/webpack/src/ivy/loader.js:64:26
 @ ../../libs/nativescript-utils/src/index.ts 1:0-41 1:0-41
 @ ./src/features/home/components/home.component.ts 2:0-71 12:41-58
 @ ./src/features/home/home.module.ts 5:0-50
 @ ./src/app.routing.ts 15:28-65
 @ ./src/app.module.ts 3:0-49 10:89-105
 @ ./src/main.ts 6:0-41 11:69-78

I did the same exercise under apps, d.ts + ios.ts + android.ts + index.ts -> same issue -> solved it by adding "**/*.ios.ts" to includes in tsconfig.app.json. But no matter what I do in the libs and tsconfig.json or tsconfig.lib.json, it's not being picked up.

Do you have any tips on how to fix this?

Start with libs/nativescript-utils/src/index.ts and the platform-specific files, then compare the library tsconfig.json and tsconfig.lib.json with apps' tsconfig.app.json. Reproduce the missing-from-TypeScript-compilation error and trace which configuration controls library file inclusion. Done means both .ios.ts and .android.ts implementations compile when imported from the library.