Resource hasValue() is false for a moment when using TransferState cached data, causing hydration to fail #62897
Description
Which @angular/* package(s) are the source of the bug?
core
Is this a regression?
No
Description
A minimal reproduction demonstrating hydration issues when using @else and @empty blocks with the control flow syntax. The app fetches Pokemon data (httpClient + rxResource + transfer state enabled) and displays three scenarios:
- Works: Uses separate @if blocks - hydration works correctly
- Broken: Uses @if/@else blocks - hydration fails
- Broken: Uses @for/@empty blocks - hydration fails
Expected: All components should hydrate properly
Actual: When using @else or @empty, components are not hydrating
Please provide a link to a minimal reproduction of the bug
https://github.com/zip-fa/ng20-new-hydration-issue
Please provide the exception or error you saw
Please provide the environment you discovered this bug in (run ng version)
ng version
_ _ ____ _ ___
/ \ _ __ __ _ _ _| | __ _ _ __ / ___| | |_ _|
/ △ \ | '_ \ / _` | | | | |/ _` | '__| | | | | | |
/ ___ \| | | | (_| | |_| | | (_| | | | |___| |___ | |
/_/ \_\_| |_|\__, |\__,_|_|\__,_|_| \____|_____|___|
|___/
Angular CLI: 20.1.3
Node: 24.2.0
Package Manager: npm 11.3.0
OS: darwin arm64
Angular: 20.1.3
... build, cli, common, compiler, compiler-cli, core, forms
... platform-browser, platform-server, router, ssr
Package Version
------------------------------------------------------
@angular-devkit/architect 0.2001.3
@angular-devkit/core 20.1.3
@angular-devkit/schematics 20.1.3
@schematics/angular 20.1.3
rxjs 7.8.2
typescript 5.8.3
Anything else?
No response