Implement core::ops::Deref and DerefMut for Crubit cpp_std::unique_ptr and virtual_unique_ptr, and Deref for shared_ptr. - #1931
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…ue_ptr` and `virtual_unique_ptr`, and `Deref` for `shared_ptr`. While C++ `std::unique_ptr` is only shallow-const, it is conventionally treated as deep-const. In order for `&unique_ptr<T>` to be usable from Rust, Crubit treats `unique_ptr` as deep-const. Mutating `T` in C++ while Rust has obtained a `&T` derived from `&unique_ptr<T>` will result in undefined behavior. Additionally, Deref and DerefMut will panic if the pointer is null, mirroring the behavior of these types in C++. Non-nullable variants of these types were considered and rejected due to additional complexity (new variant of every type) as well as the poor compatibility of the resulting types with C++ (e.g. non-null variants would be immovable in C++). PiperOrigin-RevId: 974639553
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Implement
core::ops::DerefandDerefMutfor Crubitcpp_std::unique_ptrandvirtual_unique_ptr, andDerefforshared_ptr.While C++
std::unique_ptris only shallow-const, it is conventionally treated as deep-const. In order for&unique_ptr<T>to be usable from Rust, Crubit treatsunique_ptras deep-const. MutatingTin C++ while Rust has obtained a&Tderived from&unique_ptr<T>will result in undefined behavior.Additionally, Deref and DerefMut will panic if the pointer is null, mirroring the behavior of these types in C++. Non-nullable variants of these types were considered and rejected due to additional complexity (new variant of every type) as well as the poor compatibility of the resulting types with C++ (e.g. non-null variants would be immovable in C++).