v21.2.2 seems to be unable to handle npm workspaces

Start with the linked minimal reproduction and run cd apps/test-app && ng update @angular/core@21 using Angular CLI 21.2.2 in an npm-workspaces repository. Compare the result with the same update under v20 or without workspaces; done means Angular packages are recognized as dependencies and the update proceeds without the reported error.

Command

update

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

v20

Description

While using npm workspaces, ng update @angular/core@21 (or any other angular package) with installed version @angular/cli@21 fails with the following error:

Using package manager: npm
Collecting installed dependencies...
Found 1 dependencies.
Package '@angular/core' is not a dependency.

This does not happen in the same repo with v20 installed (and trying to update to v20). It also does not happen in a repo without npm workspaces.

Minimal Reproduction

See https://github.com/jsangmeister/angular-cli-repro

I created the repo as follows:

npm init
mkdir apps
cd apps
ng new test-app

and then moving some files to the top level, e.g., the git folder.

When running cd apps/test-app && ng update @angular/core@21, the error appears.

Exception or Error

Package '@angular/core' is not a dependency.

Your Environment

_                      _                 ____ _     ___
    / \   _ __   __ _ _   _| | __ _ _ __     / ___| |   |_ _|
   / △ \ | '_ \ / _` | | | | |/ _` | '__|   | |   | |    | |
  / ___ \| | | | (_| | |_| | | (_| | |      | |___| |___ | |
 /_/   \_\_| |_|\__, |\__,_|_|\__,_|_|       \____|_____|___|
                |___/
    

Angular CLI       : 21.2.2
Angular           : 21.2.4
Node.js           : 24.10.0
Package Manager   : npm 11.9.0
Operating System  : linux x64

┌───────────────────────────┬───────────────────┬───────────────────┐
│ Package                   │ Installed Version │ Requested Version │
├───────────────────────────┼───────────────────┼───────────────────┤
│ @angular/build            │ 21.2.2            │ ^21.2.2           │
│ @angular/cli              │ 21.2.2            │ ^21.2.2           │
│ @angular/common           │ 21.2.4            │ ^21.2.0           │
│ @angular/compiler         │ 21.2.4            │ ^21.2.0           │
│ @angular/compiler-cli     │ 21.2.4            │ ^21.2.0           │
│ @angular/core             │ 21.2.4            │ ^21.2.0           │
│ @angular/forms            │ 21.2.4            │ ^21.2.0           │
│ @angular/platform-browser │ 21.2.4            │ ^21.2.0           │
│ @angular/router           │ 21.2.4            │ ^21.2.0           │
│ rxjs                      │ 7.8.2             │ ~7.8.0            │
│ typescript                │ 5.9.3             │ ~5.9.2            │
│ vitest                    │ 4.1.0             │ ^4.0.8            │
└───────────────────────────┴───────────────────┴───────────────────┘

Anything else relevant?

No response