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Genki Kondo
c72c592ecd
Summary:
## Issue
You will run into an exception like:
Animated node with tag (child) [8] does not exist
when attempting to convert an Animated node (or starting a native animation) to native when there are multiple non-style props that have AnimatedValues (this should be a very rare case, unless you have a custom native component, as most animated props are in style).
## Root cause
Due to how __makeNative is recursively called up and down the node graph, in a specific case where multiple AnimatedValues have an AnimatedProps as their child, the "connect" operation will occur before the "create" operation for the AnimatedProps node. For example:
- When a native animation is fired via Animated.timing().start(), __makeNative is called on the AnimatedValue (call this node AnimatedValueA) that is being animated. This results in the following sequence of events:
- AnimatedValueA iterates through its children (in this case, AnimatedProps) and calls child.__makeNative
- AnimatedProps iterates through all props with AnimatedValue values and calls __makeNative on them (call these nodes AnimatedValueB and AnimatedValueC).
- AnimatedValueA.__makeNative is called again, but this time, the call early exits and does not do anything.
- AnimatedValueB.__makeNative is called. This in turn calls AnimatedProps.__makeNative, which early exits (ROOT CAUSE OF BUG).
- connectAnimatedNodes is queued (undesired)
## Fix
Short of completely refactoring of how we handle converting the DAG to native (which we should do at some point - the current implementation is error prone and suboptimal. Tracking in T146991336), for now we can make AnimatedProps.__makeNative behavior consistent with AnimatedTransform and AnimatedStyle by just avoiding the early exit, so that the connectAnimatedNodes calls all occur after all native nodes have been created
Changelog:
[General][Fixed] - Fixed error during native DAG creation when there are multiple AnimatedValue props
Reviewed By: rshest
Differential Revision: D43717819
fbshipit-source-id: 258682300a2be65935646b499591acf41eabc56e