Typescript Generated an empty chunk

[AndyOGo]

I'm migrating one of my projects to typescript and suddenly my build yields empty chunks.
rollup emits this warning here:
https://github.com/rollup/rollup/blob/95400517f8bba1146d23654a881616f280db0346/src/Chunk.ts#L642-L649

This is my PR: https://github.com/AndyOGo/stylelint-declaration-strict-value/pull/119/files#diff-7ae45ad102eab3b6d7e7896acd08c427a9b25b346470d7bc6507b6481575d519

> microbundle --tsconfig tsconfig.json -i src/index.ts

Generated an empty chunk: "index"
Generated an empty chunk: "index"
Generated an empty chunk: "index"
Generated an empty chunk: "index"
Build "stylelintDeclarationStrictValue" to dist:
         21 B: index.js.gz
          5 B: index.js.br
         21 B: index.esm.js.gz
          5 B: index.esm.js.br
         21 B: index.modern.js.gz
          5 B: index.modern.js.br
         64 B: index.umd.js.gz
         53 B: index.umd.js.br

[Hotell]

How was this resolved? I'm getting same warning.

Repro:

// @file tsconfig.json
{
  "compilerOptions": {
    "declaration": true,                    
    "declarationMap": true,        
    "declarationDir": "./dist/types",
    "emitDeclarationOnly": true,
  }
}

Workaround:

if type declarations are created only via microbundle (rollup ts plugin), there are no warnings.
Looks like ts rollup plugin has some issues with emitDeclarationOnly flag.

// @file tsconfig.json
{
  "compilerOptions": {
-    "declaration": true,                    
-    "declarationMap": true,        
-    "declarationDir": "./dist/types",
-    "emitDeclarationOnly": true,
+   "noEmit": true
  }
}

[Hotell]

Update:

so if emitDeclarationOnly is explicitly set in tsconfig.json it will be propagated to typescript rollup plugin, thus the output is as expected === .d.ts files only are generated, thus there is no runtime code to rollup!

Initially I thought that babel is used for transpilation no matter what ( which from my experience, would be definitely preferred as TS has various shortcomings when doing actual transpilation)

[agilgur5]

For reference, the issue here was upstream in rpt2 ezolenko/rollup-plugin-typescript2#268, where rpt2 previously did not have any special handling of emitDeclarationOnly. The TS compiler would give back empty and that would be passed back to Rollup.

I recently added support for emitDeclarationOnly in rpt2 in ezolenko/rollup-plugin-typescript2#366, which was recently released in rpt2 0.33.0