Ramanpreet Nara 5275895af5 Roll out TurboModule block copy ...

Summary:
## Description
During TurboModule method invocation, when we convert JavaScript callbacks (i.e: jsi::Functions) into ObjC blocks inside the TurboModule jsi::HostObject, we [push them into an array](https://fburl.com/diffusion/r1n75ikx) that [gets cleared after the method gets invoked](https://fburl.com/diffusion/ubbvdmfs).

Prior to this experiment, we pushed these ObjC blocks into the array without copying them first. This goes contrary to ObjC best practices, which suggest that if you need to retain a block past its creation context for later invocation, you should defensively copy it to prevent it from being freed early. See the [Apple docs](https://developer.apple.com/library/archive/documentation/Cocoa/Conceptual/Blocks/Articles/bxUsing.html#//apple_ref/doc/uid/TP40007502-CH5-SW1):
> Typically, you shouldn’t need to copy (or retain) a block. You only need to make a copy when you expect the block to be used after destruction of the scope within which it was declared. Copying moves a block to the heap.

The diff that introduced the fix: D23764329 (https://github.com/facebook/react-native/commit/9b76e217bb16935069f0ea5b60f4c4d9b73f86d6).

Reviewed By: PeteTheHeat

Differential Revision: D25617672

fbshipit-source-id: 24863b31a2d82c8d39a91c8ea8eb3a62724b800a

2020-12-17 17:27:09 -08:00

..

android/ReactCommon

Roll out TurboModule Promise Async Dispatch

2020-12-17 17:27:09 -08:00

ios

Roll out TurboModule block copy

2020-12-17 17:27:09 -08:00