Output emitters are not properly supported in hybrid AngularJS application #60366
Description
Which @angular/* package(s) are the source of the bug?
upgrade
Is this a regression?
No
Description
Hello!
We have a big application implemented with AngularJS, which we are currently migrating to the latest Angular (19.2.2 at the moment of bug report creation). We have stumbled into the following error when trying to integrate downgraded component into AngularJS component: "TypeError: listenerFn is not a function at OutputEmitterRef.emit". I looked into the Angular source codes to find out the reason and saw the following: OutputEmitterRef.subscribe accepts a function as an argument (output_emitter_ref.ts:47) while upgrade assistant provides an object RxJS style (downgrade_component_adapter.ts:263). So I believe any case of usage of downgraded component with outputs in it will lead to this issue.
Please provide a link to a minimal reproduction of the bug
No response
Please provide the exception or error you saw
TypeError: listenerFn is not a function
at OutputEmitterRef.emit (.angular/cache/19.2.2/jsengine/vite/deps/chunk-2NASP45P.js?v=ed0c9fb9:5735:11)
at ... (proprietary code)
at .angular/cache/19.2.2/jsengine/vite/deps/@angular_upgrade_static.js?v=a8bb2139:401:31
at Scope.$digest (.angular/cache/19.2.2/jsengine/vite/deps/angular.js?v=a8bb2139:9796:29)
at Object.next (.angular/cache/19.2.2/jsengine/vite/deps/@angular_upgrade_static.js?v=a8bb2139:1277:29)
at ConsumerObserver2.next (.angular/cache/19.2.2/jsengine/vite/deps/chunk-GM2YTKEO.js?v=ed0c9fb9:583:25)
at Subscriber2._next (.angular/cache/19.2.2/jsengine/vite/deps/chunk-GM2YTKEO.js?v=ed0c9fb9:553:22)
at Subscriber2.next (.angular/cache/19.2.2/jsengine/vite/deps/chunk-GM2YTKEO.js?v=ed0c9fb9:526:12)
Please provide the environment you discovered this bug in (run ng version)
Angular CLI: 19.2.2
Node: 20.17.0
Package Manager: npm 10.8.2
OS: darwin arm64
Angular: 19.2.2
... animations, cli, common, compiler, compiler-cli, core, forms
... platform-browser, platform-browser-dynamic, router, upgrade
Package Version
---------------------------------------------------------
@angular-devkit/architect 0.1902.2
@angular-devkit/build-angular 19.2.2
@angular-devkit/core 19.2.2
@angular-devkit/schematics 19.2.2
@schematics/angular 19.2.2
rxjs 7.8.1
typescript 5.5.4
zone.js 0.15.0
Anything else?
No response