NG0600: Writing to signals is not allowed in a computed from viewChildren() signal #63291
Description
Which @angular/* package(s) are the source of the bug?
core
Is this a regression?
No
Description
I'm getting the following stackstrace:
ERROR RuntimeError: NG0600: Writing to signals is not allowed in a `computed`.
at core.mjs:22722:11
at throwInvalidWriteToSignalError (untracked-BKcld_ew.mjs:410:3)
at signalUpdateFn (untracked-BKcld_ew.mjs:455:5)
at signalFn.update (core.mjs:6833:33)
at QueryList._onDirty (core.mjs:18458:52)
at QueryList.setDirty (core.mjs:6998:10)
at _LQuery_.setDirty (core.mjs:18007:20)
at _LQueries_.dirtyQueriesWithMatches (core.mjs:18045:25)
at _LQueries_.insertView (core.mjs:18034:10)
at insertView (core.mjs:14125:14)
Which is failing on a setTimeout that nothing has to do with signals in my code. Debugging a bit and removing code around I narrowed it down to the usage of veiewChildren() singal to gather components rendered inside a table cell (to be more precise inside a Carbon Components Angular table cell). If I use this outside of the table I don't get the error. If I use @ViewChildren and then toSignal() on the changes observable I don't get this error.
Initially I thought it was a problem of the angular version i was using (v18), but now that i upgraded to v19 i can still reproduce the issue. I also debugged the Carbon code to see if there was something strange happening there, but there is nothing special there.
Please provide a link to a minimal reproduction of the bug
No response
Please provide the exception or error you saw
ERROR RuntimeError: NG0600: Writing to signals is not allowed in a `computed`.
at core.mjs:22722:11
at throwInvalidWriteToSignalError (untracked-BKcld_ew.mjs:410:3)
at signalUpdateFn (untracked-BKcld_ew.mjs:455:5)
at signalFn.update (core.mjs:6833:33)
at QueryList._onDirty (core.mjs:18458:52)
at QueryList.setDirty (core.mjs:6998:10)
at _LQuery_.setDirty (core.mjs:18007:20)
at _LQueries_.dirtyQueriesWithMatches (core.mjs:18045:25)
at _LQueries_.insertView (core.mjs:18034:10)
at insertView (core.mjs:14125:14)
Please provide the environment you discovered this bug in (run ng version)
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/ \ _ __ __ _ _ _| | __ _ _ __ / ___| | |_ _|
/ △ \ | '_ \ / _` | | | | |/ _` | '__| | | | | | |
/ ___ \| | | | (_| | |_| | | (_| | | | |___| |___ | |
/_/ \_\_| |_|\__, |\__,_|_|\__,_|_| \____|_____|___|
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Angular CLI: 19.2.15
Node: 24.1.0 (Unsupported)
Package Manager: pnpm 10.5.2
OS: darwin arm64
Angular: 19.2.14
... animations, common, compiler, compiler-cli, core, elements
... forms, language-service, localize, platform-browser
... platform-browser-dynamic, router, service-worker
Package Version
--------------------------------------------------------------
@angular-devkit/architect 0.1902.15 (cli-only)
@angular-devkit/build-angular 19.2.15
@angular-devkit/core 19.2.15 (cli-only)
@angular-devkit/schematics 19.2.15 (cli-only)
@angular/cdk 19.2.19
@angular/cli 19.2.15
@angular/material 19.2.19
@angular/material-date-fns-adapter 19.2.19
@schematics/angular 19.2.15 (cli-only)
rxjs 7.8.2
typescript 5.5.4
zone.js 0.15.1
Anything else?
No response