Bug: PagingData.empty() should not emit a LoadState.Loading refresh state [301833847]

Fixed

Bug

Status Update

No update yet.

Description

ch...@gmail.com

created issue #1

Sep 25, 2023 03:19AM

Component used: androidx.paging:paging-compose
Version used: 3.2.1
Devices/Android versions reproduced on: Pixel 6 Pro API 32 emulator

val emptyApi = MutableStateFlow(PagingData.empty<String>()).collectAsLazyPagingItems()
val emptyList = MutableStateFlow(PagingData.from(emptyList<String>())).collectAsLazyPagingItems()
assertThat(emptyApi.loadState.refresh).isInstanceOf(LoadState.Loading::class.java)
assertThat(emptyList.loadState.refresh).isNotInstanceOf(LoadState.Loading::class.java)

That last line shouldn't pass. Both empty the API call and from(emptyList()) should be marked as not loading. Ian mentioned the difference was in the cachedPageEvent that's in the from method, but not the empty one.

For what it's worth, I would consider this a breaking API change. In places where people were relying on empty to be an initial loading state to show a progress indicator, it won't if this bug is fixed.

As an alternative, maybe expose a PagingData.loading() which does what empty does now.

Comments

cl...@google.com <cl...@google.com> #2Oct 10, 2023 08:31PM

Marked as fixed.

A couple of questions:

1. Have you saw crash in real device or only in simulators?
2. Do you use dynamic feature for language ID?

to...@marginalen.se <to...@marginalen.se> #3Mar 21, 2024 07:15AM

Tested on Android 12 Emulator with custom executor, but cannot repro this issue.

cl...@google.com <cl...@google.com> #4Mar 22, 2024 01:09AM

Second crash in the description is from a real device. Experienced it myself on two different Xiaomi phones, plus lots of crashes from users in the Google Play console.
Dynamic features are not used in the application.

As a wild guess, I have downgraded build tools from 31.0.0 to 30.0.3, compileSdk from 31 to 30, and moved all work with Language ID to the service in a separate process (just to be sure that crash can kill secondary process instead of main). This combination is in beta for 2 days by now and I don't see any SIGSEGV crashes.

Issue 301833847

Description

Issue summary

Comments

cl...@google.com <cl...@google.com> #2Oct 10, 2023 08:31PM

to...@marginalen.se <to...@marginalen.se> #3Mar 21, 2024 07:15AM

cl...@google.com <cl...@google.com> #4Mar 22, 2024 01:09AM

Add comment

Issue metadata