Summary:
Pull Request resolved: https://github.com/facebook/react-native/pull/36325
A lot of the code in YogaLayoutableShadowNode expects a 1:1 mapping from ShadowNode children to Yoga Node children, which is not always the case, e.g. for `RawTextShadowNode` (if text, or a number coerced to text, is rendered outside a Text component).
In S323291 we saw this cause memory corruption due to later invalid static_cast. I changed the casting mechanism to terminte instead of corrupting memory, but there is logic here that we need to make permissive (I think D29894182 (https://github.com/facebook/react-native/commit/d3e836245b5fab2e0299dd06901de74dff767b63) also tried to previously do this?).
Normally Text will be rendered inside of a ParagraphShadowNode, where "Text" from React is mapped to ParagraphShadowNode (which is layoutable), "VirtualText" is mapped to TextShadowNode (which is also not layoutable), then finally the text fragment is mapped to "RawTextShadowNode". Arguably React renderer behavior should be not to send anything to native, but we can provide a generalized solution in YogaLayoutableShadowNode to handle any other cases of this issue.
This solution works by filtering ShadowNode children to those which are YogaLayoutable, then only ever operating on that list of children. This means a guaranteed invariant of the nodes we operate on being layoutable (vs the adhoc error handling right now for when they are not), and means we maintain the index based mapping of ShadowNode children to Yoga Node children.
Note, there is another similar API, `getLayoutableChildNodes()` which is protected and returns a filtered list of LayoutableShadowNode. This is public, to allow querying/setting layout results, whearas the similar operations in YogaLayoutableShadowNode are instead an implementation detail.
Changelog:
[General][Fixed] - Fix YogaLayoutableShadowNode handling of non-layoutable children
Reviewed By: sammy-SC
Differential Revision: D43657405
fbshipit-source-id: 8ed136b03b4da15a5e7dfbdd5539b04a2952420d
Summary:
Pull Request resolved: https://github.com/facebook/react-native/pull/36258
This fixes a few instances where YogaLayoutableShadowNode (or general shadownode casting) could offer better memory safety.
1. The reference form of traitCast() now terminates on invalid cast, instead of debug assert, since it is better to crash in production than to corrupt memory (which will crash somewhere later, in a much more confusing way).
2. We use traitCast() in more places where we previously would static_cast. This means needing to formally add a mutable version.
3. We bounds-check yoga children access in a single place by using `std::vector` `at()` instead of `[]`.
4. Removed `Trait::UnreservedTrait1` API, since multiple libraries using it can collide and we lose the memory safety benefits of `traitCast`.
This change is in response to a bug where `YogaLayoutableShadowNode` may perform an invalid `static_cast` of `RawTextShadowNode` if a text or number is rendered directly inside of a `<View>` (instead of a `<Text>` element).
This does not yet fix the underlying logic of YogaLayoutableShadowNode to act gracefully when a RawTextShadowNode makes its way into children. We just terminate, instead of corrupting memory.
Changelog:
[General][Breaking] - Better Fabric ShadowNode Memory Safety (Removes `Trait::UnreservedTrait` API)
Reviewed By: javache
Differential Revision: D43271779
fbshipit-source-id: 727c1230f72664bf4d261871c66ca61ddf0d5ffa
Summary:
Calculation of TransformedFrames was a method introduced by D37994809 (https://github.com/facebook/react-native/commit/64528e5faa445907b8287b412c344f30c20fca61) to fix rendering of inverted flat lists.
We found that this operation is crashing in fb4a causing the UBN T127619309
This diff creates a feature flag to disable the calculation of TransformedFrames in Layoutable ShadowNodes. **The goal of this diff is to revert the behavior introduced by D37994809 (https://github.com/facebook/react-native/commit/64528e5faa445907b8287b412c344f30c20fca61)**
The featureFlag is disabled in fb4a and enabled in react AR (because ReactAr apps relies on the calculation of TransformedFrames and these apps are not affected)
The root cause of the bug will be fixed by D38280674 (which still requires more testing and investigation)
changelog: [internal] internal
Reviewed By: JoshuaGross
Differential Revision: D38286857
fbshipit-source-id: 721cd0554ae6a6b369b3f8dbb584160a270d0f18
Summary:
Fix todo and inconsistency across codebase. It's better to have just one way to refer to these types.
Changelog: [Internal]
Reviewed By: philIip
Differential Revision: D37653146
fbshipit-source-id: e82f09caa6cd6eec5512b78f413708d9c04a7a83
Summary:
changelog: [internal]
You can read more about this rule on https://clang.llvm.org/extra/clang-tidy/checks/modernize-pass-by-value.html
# Isn't it wasteful to copy? Isn't reference more efficient?
This rule of thumb is no longer true since C++11 with move semantics. Let's look at some examples.
# Option one
```
class TextHolder
{
public:
TextBox(std::string const &text) : text_(text) {}
private:
std::string text_;
};
```
By using reference here, we prevent the caller from using rvalue to and avoiding copy. Regardless of what the caller passes in, copy always happens.
# Option two
```
class TextHolder
{
public:
TextBox(std::string const &text) : text_(text) {}
TextBox(std::string &&text) : text_(std::move(text)) {}
private:
std::string text_;
};
```
Here, we provide two constructors, one for const reference and one for rvalue reference. This gives the caller option to avoid copy. But now we have two constructors, which is not ideal.
# Option three (what we do in this diff)
```
class TextHolder
{
public:
TextBox(std::string text) : text_(std::move(text)) {}
private:
std::string text_;
};
```
Here, the caller has option to avoid copy and we only have single constructor.
Reviewed By: fkgozali, JoshuaGross
Differential Revision: D33276841
fbshipit-source-id: 619d5123d2e28937b22874650366629f24f20a63
Summary:
Renaming the `better` utilities to `butter`:
- to prevent claims that this library is superior to others - it really depends on use cases
- to indicate ease of use throughout the codebase, easily spread like butter
Changelog: [C++][Changed] Renaming C++ better util to butter, used by Fabric internals
Reviewed By: JoshuaGross
Differential Revision: D33242764
fbshipit-source-id: 26dc95d9597c61ce8e66708e44ed545e0fc5cff5
Summary:
Fabric core uses a lot of traits - I am reserving a few more for core usage, and also exposing a few "unreserved" traits.
It is recommended that all custom components that do use traits rely on these constants instead of hard-coding any trait values. That way, in the unlikely event that these values change in the future, it will not break components.
Changelog: [Internal]
Reviewed By: cortinico, RSNara
Differential Revision: D30401743
fbshipit-source-id: fb2e8f5cf33c94e31a0c25a89055acfc4eccf066
Summary:
Changelog: [internal]
`ShadowNode::Unshared` is preferred over `UnsharedShadowNode`. This diff removes last uses of the alias.
Differential Revision: D27407197
fbshipit-source-id: aa1440f80dcab523d61c186f2d3ce052f314e52c
Summary:
Changelog: [internal]
### Why does the crash happen?
The crash can happen if runtime is destroyed before background executor lambda is run. Destroying a shadow node after runtime leads to a crash through the chain of ownerships.
Chain of ownership:
`ShadowNode -> ShadowNodeFamily -> EventEmitter -> EventTarget -> Pointer`
Pointer tries to call `invalidate` method on raw pointer to the runtime which is gone.
https://www.internalfb.com/intern/diffusion/FBS/browse/master/xplat/js/react-native-github/ReactCommon/jsi/jsi/jsi.h?commit=2ee3ae0c6a64&lines=335-339
To work around this, weak pointers are passed to lambda. This way the lambda is less likely to be the last owner of shadow nodes. Possibility of race still exists but it less likely to happen.
## Other solution
Alternatively, we could make sure native Runnable queue in Java is emptied as part of tear down process. We can even implement both solutions as they are semantically correct.
Reviewed By: shergin
Differential Revision: D26582554
fbshipit-source-id: b1b8a92237902bc4c40376176f575caa24a41a05
Summary:
Changelog: [internal]
If ShadowNode has not been mounted, forward rawProps from `sourceShadowNode` to newly cloned shadow node.
This is Android specific change, on iOS the logic should remain unchanged.
Reviewed By: JoshuaGross
Differential Revision: D26049264
fbshipit-source-id: 7c201bc2d4e99eec024065714d2172c5c817153c
Summary:
This diff removes the inner folder of react/renderer/core, moving all its files into react/renderer/core
This is necessary to simplify the compilation of Fabric in OSS
More details: https://fb.quip.com/amaRA631DX3K
changelog: [internal] Internal
Reviewed By: fkgozali, JoshuaGross
Differential Revision: D22875854
fbshipit-source-id: e2d969c3ec67eab1bbdc9288e5a4285c740fa944
