MagicString is not a constructor

[sysmat]

Which @angular/* package(s) are the source of the bug?

compiler

Is this a regression?

Yes

Description

when building lib "type": "module" with "vite": "^8.2.0" and using it in angualar lib, I get error

Please provide a link to a minimal reproduction of the bug

No response

Please provide the exception or error you saw

> ng build my-lib

Building Angular Package

------------------------------------------------------------------------------
Building entry point 'my-lib'
------------------------------------------------------------------------------
✔ Compiling with Angular sources in partial compilation mode.
✖ 
MagicString is not a constructor

Please provide the environment you discovered this bug in (run ng version)

Angular CLI       : 22.1.2
Node.js           : 24.18.0
Package Manager   : npm 11.16.0
Operating System  : win32 x64

Anything else?

npm ls magic-string

├─┬ @angular/build@22.1.2
│ └── magic-string@1.0.0
├─┬ @angular/cli@22.1.2
│ └─┬ @angular-devkit/schematics@22.1.2
│   └── magic-string@1.0.0 deduped
└─┬ ng-packagr@22.1.0
  └─┬ rollup-plugin-dts@6.5.0
    └── magic-string@1.1.0

[sysmat]

• [vite:vue] MagicString is not a constructor nuxt/test-utils#1690 (comment)

[alan-agius4]

Root cause Swatinem/rollup-plugin-dts#404 will publish a new ng-packagr version to downgrade the version.

[kle-pra]

There seems to be a problem with rollup plugin dts inside:

node_modules/@angular node_modules/ng-packagr node_modules/rollup-plugin-dts

if we change line var MagicString = require('magic-string'); -> var MagicString = require('magic-string').default; it seems to work

[alan-agius4]

Closed via ng-packagr/ng-packagr#3374