VsCode flag out error for the tsconfig.lib.json, when using angular cli to generate library

[hannah23280]

Command

generate

Is this a regression?

• Yes, this behavior used to work in the previous version

The previous version in which this bug was not present was

No response

Description

The vscode complains the generated tsconfig.lib.json has the following error "Option 'inlineSources can only be used when either option '--inlineSourceMap' or option '--sourceMap' is provided.ts"

Below is the default tsconfig.lib.json generated for the angular library

{
  "extends": "../../tsconfig.json",
  "compilerOptions": {
    "outDir": "../../out-tsc/lib",
    "declaration": true,
    "declarationMap": true,
    "inlineSources": true,
    "types": []
  },
  "include": [
    "src/**/*.ts"
  ],
  "exclude": [
    "**/*.spec.ts"
  ]
}

Minimal Reproduction

Use angular cli to generate a library.
Use vscode to open the tsconfig.lib.json.

Exception or Error

Your Environment

Angular CLI       : 21.0.0-next.8
Angular           : 21.0.0-next.9
Node.js           : 22.21.0
Package Manager   : npm 10.9.4
Operating System  : win32 x64

┌───────────────────────────┬───────────────────┬───────────────────┐
│ Package                   │ Installed Version │ Requested Version │
├───────────────────────────┼───────────────────┼───────────────────┤
│ @angular/build            │ 21.0.0-next.8     │ ^21.0.0-next.8    │
│ @angular/cli              │ 21.0.0-next.8     │ ^21.0.0-next.8    │
│ @angular/common           │ 21.0.0-next.9     │ ^21.0.0-next.0    │
│ @angular/compiler         │ 21.0.0-next.9     │ ^21.0.0-next.0    │
│ @angular/compiler-cli     │ 21.0.0-next.9     │ ^21.0.0-next.0    │
│ @angular/core             │ 21.0.0-next.9     │ ^21.0.0-next.0    │
│ @angular/forms            │ 21.0.0-next.9     │ ^21.0.0-next.0    │
│ @angular/platform-browser │ 21.0.0-next.9     │ ^21.0.0-next.0    │
│ @angular/router           │ 21.0.0-next.9     │ ^21.0.0-next.0    │
│ ng-packagr                │ 21.0.0-rc.0       │ ^21.0.0-next.0    │
│ rxjs                      │ 7.8.2             │ ~7.8.0            │
│ typescript                │ 5.9.3             │ ~5.9.2            │

Anything else relevant?

No response