ng build --watch does not update the top level package.json version after subpackage changes

[robmv]

Command

build

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

~19.2.14

Description

In Angular 19.2.x, having a library project with multiple sub-packages (ng-package.json) for example 'mylib/core, when running ng build --watch and making changes on a source file of mylib/core, the cli proceeded to build not only mylib/core but their dependent subpackages in the same project. So it printed multiple:

Building entry point 'mylib/core'

One for each dependent subpackage. Now it only prints one in Angular 21.1.4, for mylib/core. As a consequence of this, when using nb build --watch the top level package.json version hash is not changed, and this cause problems in mono repos that are linking locally to this library, the ng serve of the client application of the library doesn't notice changes because the version has not changed

Minimal Reproduction

• Clone https://github.com/robmv/ng-build-watch-bug
• Build it using ng build --watch
• Record the output of grep version dist/mylib/package.json
• Edit the file projects/mylib/core/src/public-api.ts, like modifying the value of the only constant defined there.
• Notice the output of the build prints Building entry point 'mylib/core' but only that subpackage, no for entry point 'mylib'
• Compare the output of grep version dist/mylib/package.json with the previous recorded value.
• In my installation the output is always the same value: 0.0.0-watch+1771439999045 no matter what changes I make inside the core sub-package.

Exception or Error

Your Environment

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


Angular CLI       : 21.1.4
Angular           : 21.1.4
Node.js           : 22.22.0
Package Manager   : npm 10.9.4
Operating System  : linux x64

┌───────────────────────────┬───────────────────┬───────────────────┐
│ Package                   │ Installed Version │ Requested Version │
├───────────────────────────┼───────────────────┼───────────────────┤
│ @angular/build            │ 21.1.4            │ ^21.1.4           │
│ @angular/cli              │ 21.1.4            │ ^21.1.4           │
│ @angular/common           │ 21.1.4            │ ^21.1.0           │
│ @angular/compiler         │ 21.1.4            │ ^21.1.0           │
│ @angular/compiler-cli     │ 21.1.4            │ ^21.1.0           │
│ @angular/core             │ 21.1.4            │ ^21.1.0           │
│ @angular/forms            │ 21.1.4            │ ^21.1.0           │
│ @angular/platform-browser │ 21.1.4            │ ^21.1.0           │
│ @angular/router           │ 21.1.4            │ ^21.1.0           │
│ ng-packagr                │ 21.1.0            │ ^21.1.0           │
│ rxjs                      │ 7.8.2             │ ~7.8.0            │
│ typescript                │ 5.9.3             │ ~5.9.2            │
│ vitest                    │ 4.0.18            │ ^4.0.8            │
└───────────────────────────┴───────────────────┴───────────────────┘

Anything else relevant?

No response

[robmv]

I noticed this only happens when sub-package changes are not related to its public API, For example the reproduction steps of changing a constant value or changing a method implementation, etc, others changes trigger the update of the top level package.json's version. IMHO the top level package version should be updated always in watch mode, for any meaningful change.