fix(firebase_database): Firebase_Database Assertion error on push for sorted FirebaseAnimatedList

[dipakp2726]

Description

fixed OnChildAdded so its get the correct index when new key is pushed.

Related Issues

fixes #7100,#9837

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[dipakp2726]

it gives index always -1 when sorting is there

[dipakp2726]

can some one give a reply/acknowledgment here?

@russellwheatley

[dipakp2726]

both failed checks are irrelevant to firebase_database

[russellwheatley]

@dipakp2726 Could you merge with master locally and push to remote, please?

[dipakp2726]

@dipakp2726 Could you merge with master locally and push to remote, please?

merged

[dipakp2726]

https://github.com/dipakp2726/firebase_database_reproduce
on main -> branch it throws assertion error which use latest firebase database
solution branch -> which uses firebase_database from my fork doesn't throw assertion error

[dipakp2726]

test for sorted list doesn't exists

[dipakp2726]

looking at the existing tests, I am not sure if I can write a test that can produce this since there is a lot of mocking going on that I am not able to understand.
I can write an integration test that can produce this but I think it's not suitable since it will require a firebase project to open always,

can you give me a suggestion regarding the writing test that produces it?
@Lyokone

[Lyokone]

@dipakp2726 You can find the e2e test (that open a firebase simulator in CI) here: tests/integration_test/firebase_database/database_e2e.dart

Looking at the issue in depth, its caused by this line:

packages/firebase_database/firebase_database/lib/src/database_event.dart:20

DataSnapshot get snapshot => DataSnapshot._(_delegate.snapshot);

Where we don't cache the result of the snapshot.

I would modify this file with the content of #9899

Can you try this PR to see if you see the expected results on your end?

[dipakp2726]

@Lyokone #9899 resolves the issue,

[dipakp2726]

what's next? @Lyokone

[Lyokone]

@dipakp2726 the #9899 is being reviewed, once it has been approved it will be merged and we can close this PR as well

[dipakp2726]

thank you