Add featureflag to not re-order mount items in FabricMountingManager #46702
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…acebook#46702) Summary: In facebook#44188, we've started combining multiple transactions in a single transaction, to meet React's atomicity requirements, while also dealing with the constraints of Android's Fabric implementation. This revealed a bug where in some scenarios (especially when using transitions), a node may be deleted and created during the same transaction. The current implementation of FabricMountingManager assumes it can safely reorder some operations, which it does to optimize the size of IntBufferBatch mount items. This is however incorrect and unsafe when multiple transactions are merged. **Example:** Differentiator output: ``` # Transaction 1 Remove facebook#100 from facebook#11 Delete facebook#100 # Transaction 2 Create facebook#100 Insert facebook#100 into facebook#11 ``` FabricMountingManager output ``` Remove facebook#100 from facebook#11 Insert facebook#100 into facebook#11 Delete facebook#100 ``` Note that the create action is also skipped, because we only update `allocatedViewTags` after processing all mutations, leading FabricMountingManager to assume creation is not required. This leads to an invalid state in SurfaceMountingManager, which will be surfaced as a crash in `getViewState` on the next mutation that interacts with these views. Changelog: [Android][Fixed] Fix crash in getViewState when using suspense fallbacks. Differential Revision: D63148523
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This pull request was exported from Phabricator. Differential Revision: D63148523 |
…acebook#46702) Summary: Pull Request resolved: facebook#46702 In facebook#44188, we've started combining multiple transactions in a single transaction, to meet React's atomicity requirements, while also dealing with the constraints of Android's Fabric implementation. This revealed a bug where in some scenarios (especially when using transitions), a node may be deleted and created during the same transaction. The current implementation of FabricMountingManager assumes it can safely reorder some operations, which it does to optimize the size of IntBufferBatch mount items. This is however incorrect and unsafe when multiple transactions are merged. **Example:** Differentiator output: ``` # Transaction 1 Remove facebook#100 from facebook#11 Delete facebook#100 # Transaction 2 Create facebook#100 Insert facebook#100 into facebook#11 ``` FabricMountingManager output ``` Remove facebook#100 from facebook#11 Insert facebook#100 into facebook#11 Delete facebook#100 ``` Note that the create action is also skipped, because we only update `allocatedViewTags` after processing all mutations, leading FabricMountingManager to assume creation is not required. This leads to an invalid state in SurfaceMountingManager, which will be surfaced as a crash in `getViewState` on the next mutation that interacts with these views. Changelog: [Android][Fixed] Fix crash in getViewState when using suspense fallbacks. Reviewed By: sammy-SC Differential Revision: D63148523
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This pull request was successfully merged by @javache in bd133b5 When will my fix make it into a release? | How to file a pick request? |
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Summary: We previously fixed Differentiator generating an incorrect parentTag (facebook#48055), but this can lead to crashes in Android UI due to reordering that happens in the Android mounting layer. While we have an experiment to disable this reordering (facebook#46702) this currently has a negative performance impact which needs to be addressed. As a mitigation, we can make the lookup of parentTag's ViewManager state nullable. We only require this to support `needsCustomLayoutForChildren`, which is not commonly used, and seems acceptable to drop in this scenario. Changelog: [Android][Changed] Do not crash when parent view state can't be found Differential Revision: D70966621
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Summary: We previously fixed Differentiator generating an incorrect parentTag (facebook#48055), but this can lead to crashes in Android UI due to reordering that happens in the Android mounting layer. While we have an experiment to disable this reordering (facebook#46702) this currently has a negative performance impact which needs to be addressed. As a mitigation, we can make the lookup of parentTag's ViewManager state nullable. We only require this to support `needsCustomLayoutForChildren`, which is not commonly used, and seems acceptable to drop in this scenario. Changelog: [Android][Changed] Do not crash when parent view state can't be found Differential Revision: D70966621
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Summary: Pull Request resolved: #49951 We previously fixed Differentiator generating an incorrect parentTag (#48055), but this can lead to crashes in Android UI due to reordering that happens in the Android mounting layer. While we have an experiment to disable this reordering (#46702) this currently has a negative performance impact which needs to be addressed. As a mitigation, we can make the lookup of parentTag's ViewManager state nullable. We only require this to support `needsCustomLayoutForChildren`, which is not commonly used, and seems acceptable to drop in this scenario. Changelog: [Android][Changed] Do not crash when parent view state can't be found Reviewed By: NickGerleman Differential Revision: D70966621 fbshipit-source-id: 33d0b6a90860788a4c9a8c6cea36c2c72c1392e1
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…#49951) Summary: Pull Request resolved: facebook#49951 We previously fixed Differentiator generating an incorrect parentTag (facebook#48055), but this can lead to crashes in Android UI due to reordering that happens in the Android mounting layer. While we have an experiment to disable this reordering (facebook#46702) this currently has a negative performance impact which needs to be addressed. As a mitigation, we can make the lookup of parentTag's ViewManager state nullable. We only require this to support `needsCustomLayoutForChildren`, which is not commonly used, and seems acceptable to drop in this scenario. Changelog: [Android][Changed] Do not crash when parent view state can't be found Reviewed By: NickGerleman Differential Revision: D70966621 fbshipit-source-id: 33d0b6a90860788a4c9a8c6cea36c2c72c1392e1
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…#49951) Summary: Pull Request resolved: facebook#49951 We previously fixed Differentiator generating an incorrect parentTag (facebook#48055), but this can lead to crashes in Android UI due to reordering that happens in the Android mounting layer. While we have an experiment to disable this reordering (facebook#46702) this currently has a negative performance impact which needs to be addressed. As a mitigation, we can make the lookup of parentTag's ViewManager state nullable. We only require this to support `needsCustomLayoutForChildren`, which is not commonly used, and seems acceptable to drop in this scenario. Changelog: [Android][Changed] Do not crash when parent view state can't be found Reviewed By: NickGerleman Differential Revision: D70966621 fbshipit-source-id: 33d0b6a90860788a4c9a8c6cea36c2c72c1392e1
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Summary:
In #44188, we've started combining multiple transactions in a single transaction, to meet React's atomicity requirements, while also dealing with the constraints of Android's Fabric implementation.
This revealed a bug where in some scenarios (especially when using transitions), a node may be deleted and created during the same transaction. The current implementation of FabricMountingManager assumes it can safely reorder some operations, which it does to optimize the size of IntBufferBatch mount items. This is however incorrect and unsafe when multiple transactions are merged.
Example:
Differentiator output:
FabricMountingManager output
Note that the create action is also skipped, because we only update
allocatedViewTagsafter processing all mutations, leading FabricMountingManager to assume creation is not required.This leads to an invalid state in SurfaceMountingManager, which will be surfaced as a crash in
getViewStateon the next mutation that interacts with these views.Changelog: [Android][Fixed] Fix crash in getViewState when using suspense fallbacks.
Differential Revision: D63148523