0403948aa2
# Background In `no_std` compatible crates, there is often an `std` feature which will allow access to the standard library. Currently, with the `std` feature _enabled_, the [`std::prelude`](https://doc.rust-lang.org/std/prelude/index.html) is implicitly imported in all modules. With the feature _disabled_, instead the [`core::prelude`](https://doc.rust-lang.org/core/prelude/index.html) is implicitly imported. This creates a subtle and pervasive issue where `alloc` items _may_ be implicitly included (if `std` is enabled), or must be explicitly included (if `std` is not enabled). # Objective - Make the implicit imports for `no_std` crates consistent regardless of what features are/not enabled. ## Solution - Replace the `cfg_attr` "double negative" `no_std` attribute with conditional compilation to _include_ `std` as an external crate. ```rust // Before #![cfg_attr(not(feature = "std"), no_std)] // After #![no_std] #[cfg(feature = "std")] extern crate std; ``` - Fix imports that are currently broken but are only now visible with the above fix. ## Testing - CI ## Notes I had previously used the "double negative" version of `no_std` based on general consensus that it was "cleaner" within the Rust embedded community. However, this implicit prelude issue likely was considered when forming this consensus. I believe the reason why is the items most affected by this issue are provided by the `alloc` crate, which is rarely used within embedded but extensively used within Bevy.
822 lines
26 KiB
Rust
822 lines
26 KiB
Rust
pub mod access;
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pub use access::*;
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mod error;
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pub use error::*;
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mod parse;
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pub use parse::ParseError;
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use parse::PathParser;
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use crate::{PartialReflect, Reflect};
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use alloc::vec::Vec;
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use core::fmt;
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use derive_more::derive::From;
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use thiserror::Error;
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type PathResult<'a, T> = Result<T, ReflectPathError<'a>>;
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/// An error returned from a failed path string query.
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#[derive(Error, Debug, PartialEq, Eq)]
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pub enum ReflectPathError<'a> {
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/// An error caused by trying to access a path that's not able to be accessed,
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/// see [`AccessError`] for details.
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#[error(transparent)]
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InvalidAccess(AccessError<'a>),
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/// An error that occurs when a type cannot downcast to a given type.
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#[error("Can't downcast result of access to the given type")]
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InvalidDowncast,
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/// An error caused by an invalid path string that couldn't be parsed.
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#[error("Encountered an error at offset {offset} while parsing `{path}`: {error}")]
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ParseError {
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/// Position in `path`.
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offset: usize,
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/// The path that the error occurred in.
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path: &'a str,
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/// The underlying error.
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error: ParseError<'a>,
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},
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}
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impl<'a> From<AccessError<'a>> for ReflectPathError<'a> {
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fn from(value: AccessError<'a>) -> Self {
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ReflectPathError::InvalidAccess(value)
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}
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}
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/// Something that can be interpreted as a reflection path in [`GetPath`].
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pub trait ReflectPath<'a>: Sized {
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/// Gets a reference to the specified element on the given [`Reflect`] object.
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///
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/// See [`GetPath::reflect_path`] for more details,
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/// see [`element`](Self::element) if you want a typed return value.
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fn reflect_element(self, root: &dyn PartialReflect) -> PathResult<'a, &dyn PartialReflect>;
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/// Gets a mutable reference to the specified element on the given [`Reflect`] object.
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///
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/// See [`GetPath::reflect_path_mut`] for more details.
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fn reflect_element_mut(
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self,
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root: &mut dyn PartialReflect,
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) -> PathResult<'a, &mut dyn PartialReflect>;
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/// Gets a `&T` to the specified element on the given [`Reflect`] object.
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///
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/// See [`GetPath::path`] for more details.
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fn element<T: Reflect>(self, root: &dyn PartialReflect) -> PathResult<'a, &T> {
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self.reflect_element(root).and_then(|p| {
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p.try_downcast_ref::<T>()
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.ok_or(ReflectPathError::InvalidDowncast)
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})
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}
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/// Gets a `&mut T` to the specified element on the given [`Reflect`] object.
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///
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/// See [`GetPath::path_mut`] for more details.
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fn element_mut<T: Reflect>(self, root: &mut dyn PartialReflect) -> PathResult<'a, &mut T> {
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self.reflect_element_mut(root).and_then(|p| {
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p.try_downcast_mut::<T>()
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.ok_or(ReflectPathError::InvalidDowncast)
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})
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}
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}
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impl<'a> ReflectPath<'a> for &'a str {
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fn reflect_element(self, mut root: &dyn PartialReflect) -> PathResult<'a, &dyn PartialReflect> {
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for (access, offset) in PathParser::new(self) {
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let a = access?;
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root = a.element(root, Some(offset))?;
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}
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Ok(root)
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}
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fn reflect_element_mut(
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self,
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mut root: &mut dyn PartialReflect,
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) -> PathResult<'a, &mut dyn PartialReflect> {
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for (access, offset) in PathParser::new(self) {
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root = access?.element_mut(root, Some(offset))?;
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}
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Ok(root)
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}
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}
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/// A trait which allows nested [`Reflect`] values to be retrieved with path strings.
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///
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/// Using these functions repeatedly with the same string requires parsing the string every time.
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/// To avoid this cost, it's recommended to construct a [`ParsedPath`] instead.
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///
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/// # Syntax
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///
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/// ## Structs
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///
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/// Field paths for [`Struct`] elements use the standard Rust field access syntax of
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/// dot and field name: `.field_name`.
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///
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/// Additionally, struct fields may be accessed by their index within the struct's definition.
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/// This is accomplished by using the hash symbol (`#`) in place of the standard dot: `#0`.
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///
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/// Accessing a struct's field by index can speed up fetches at runtime due to the removed
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/// need for string matching.
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/// And while this can be more performant, it's best to keep in mind the tradeoffs when
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/// utilizing such optimizations.
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/// For example, this can result in fairly fragile code as the string paths will need to be
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/// kept in sync with the struct definitions since the order of fields could be easily changed.
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/// Because of this, storing these kinds of paths in persistent storage (i.e. game assets)
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/// is strongly discouraged.
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///
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/// Note that a leading dot (`.`) or hash (`#`) token is implied for the first item in a path,
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/// and may therefore be omitted.
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///
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/// ### Example
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/// ```
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/// # use bevy_reflect::{GetPath, Reflect};
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/// #[derive(Reflect)]
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/// struct MyStruct {
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/// value: u32
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/// }
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///
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/// let my_struct = MyStruct { value: 123 };
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/// // Access via field name
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/// assert_eq!(my_struct.path::<u32>(".value").unwrap(), &123);
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/// // Access via field index
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/// assert_eq!(my_struct.path::<u32>("#0").unwrap(), &123);
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/// ```
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///
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/// ## Tuples and Tuple Structs
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///
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/// [`Tuple`] and [`TupleStruct`] elements also follow a conventional Rust syntax.
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/// Fields are accessed with a dot and the field index: `.0`.
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///
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/// Note that a leading dot (`.`) token is implied for the first item in a path,
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/// and may therefore be omitted.
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///
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/// ### Example
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/// ```
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/// # use bevy_reflect::{GetPath, Reflect};
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/// #[derive(Reflect)]
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/// struct MyTupleStruct(u32);
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///
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/// let my_tuple_struct = MyTupleStruct(123);
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/// assert_eq!(my_tuple_struct.path::<u32>(".0").unwrap(), &123);
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/// ```
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///
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/// ## Lists and Arrays
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///
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/// [`List`] and [`Array`] elements are accessed with brackets: `[0]`.
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///
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/// ### Example
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/// ```
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/// # use bevy_reflect::{GetPath};
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/// let my_list: Vec<u32> = vec![1, 2, 3];
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/// assert_eq!(my_list.path::<u32>("[2]").unwrap(), &3);
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/// ```
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///
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/// ## Enums
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///
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/// Pathing for [`Enum`] elements works a bit differently than in normal Rust.
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/// Usually, you would need to pattern match an enum, branching off on the desired variants.
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/// Paths used by this trait do not have any pattern matching capabilities;
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/// instead, they assume the variant is already known ahead of time.
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///
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/// The syntax used, therefore, depends on the variant being accessed:
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/// - Struct variants use the struct syntax (outlined above)
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/// - Tuple variants use the tuple syntax (outlined above)
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/// - Unit variants have no fields to access
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///
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/// If the variant cannot be known ahead of time, the path will need to be split up
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/// and proper enum pattern matching will need to be handled manually.
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///
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/// ### Example
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/// ```
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/// # use bevy_reflect::{GetPath, Reflect};
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/// #[derive(Reflect)]
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/// enum MyEnum {
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/// Unit,
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/// Tuple(bool),
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/// Struct {
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/// value: u32
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/// }
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/// }
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///
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/// let tuple_variant = MyEnum::Tuple(true);
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/// assert_eq!(tuple_variant.path::<bool>(".0").unwrap(), &true);
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///
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/// let struct_variant = MyEnum::Struct { value: 123 };
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/// // Access via field name
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/// assert_eq!(struct_variant.path::<u32>(".value").unwrap(), &123);
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/// // Access via field index
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/// assert_eq!(struct_variant.path::<u32>("#0").unwrap(), &123);
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///
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/// // Error: Expected struct variant
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/// assert!(matches!(tuple_variant.path::<u32>(".value"), Err(_)));
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/// ```
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///
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/// # Chaining
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///
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/// Using the aforementioned syntax, path items may be chained one after another
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/// to create a full path to a nested element.
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///
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/// ## Example
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/// ```
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/// # use bevy_reflect::{GetPath, Reflect};
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/// #[derive(Reflect)]
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/// struct MyStruct {
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/// value: Vec<Option<u32>>
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/// }
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///
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/// let my_struct = MyStruct {
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/// value: vec![None, None, Some(123)],
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/// };
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/// assert_eq!(
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/// my_struct.path::<u32>(".value[2].0").unwrap(),
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/// &123,
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/// );
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/// ```
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///
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/// [`Struct`]: crate::Struct
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/// [`Tuple`]: crate::Tuple
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/// [`TupleStruct`]: crate::TupleStruct
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/// [`List`]: crate::List
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/// [`Array`]: crate::Array
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/// [`Enum`]: crate::Enum
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#[diagnostic::on_unimplemented(
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message = "`{Self}` does not implement `GetPath` so cannot be accessed by reflection path",
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note = "consider annotating `{Self}` with `#[derive(Reflect)]`"
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)]
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pub trait GetPath: PartialReflect {
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/// Returns a reference to the value specified by `path`.
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///
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/// To retrieve a statically typed reference, use
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/// [`path`][GetPath::path].
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fn reflect_path<'p>(&self, path: impl ReflectPath<'p>) -> PathResult<'p, &dyn PartialReflect> {
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path.reflect_element(self.as_partial_reflect())
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}
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/// Returns a mutable reference to the value specified by `path`.
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///
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/// To retrieve a statically typed mutable reference, use
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/// [`path_mut`][GetPath::path_mut].
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fn reflect_path_mut<'p>(
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&mut self,
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path: impl ReflectPath<'p>,
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) -> PathResult<'p, &mut dyn PartialReflect> {
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path.reflect_element_mut(self.as_partial_reflect_mut())
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}
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/// Returns a statically typed reference to the value specified by `path`.
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///
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/// This will automatically handle downcasting to type `T`.
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/// The downcast will fail if this value is not of type `T`
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/// (which may be the case when using dynamic types like [`DynamicStruct`]).
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///
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/// [`DynamicStruct`]: crate::DynamicStruct
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fn path<'p, T: Reflect>(&self, path: impl ReflectPath<'p>) -> PathResult<'p, &T> {
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path.element(self.as_partial_reflect())
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}
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/// Returns a statically typed mutable reference to the value specified by `path`.
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///
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/// This will automatically handle downcasting to type `T`.
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/// The downcast will fail if this value is not of type `T`
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/// (which may be the case when using dynamic types like [`DynamicStruct`]).
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///
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/// [`DynamicStruct`]: crate::DynamicStruct
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fn path_mut<'p, T: Reflect>(&mut self, path: impl ReflectPath<'p>) -> PathResult<'p, &mut T> {
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path.element_mut(self.as_partial_reflect_mut())
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}
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}
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// Implement `GetPath` for `dyn Reflect`
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impl<T: Reflect + ?Sized> GetPath for T {}
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/// An [`Access`] combined with an `offset` for more helpful error reporting.
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#[derive(Clone, Debug, PartialEq, PartialOrd, Ord, Eq, Hash)]
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pub struct OffsetAccess {
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/// The [`Access`] itself.
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pub access: Access<'static>,
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/// A character offset in the string the path was parsed from.
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pub offset: Option<usize>,
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}
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impl From<Access<'static>> for OffsetAccess {
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fn from(access: Access<'static>) -> Self {
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OffsetAccess {
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access,
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offset: None,
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}
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}
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}
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/// A pre-parsed path to an element within a type.
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///
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/// This struct can be constructed manually from its [`Access`]es or with
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/// the [parse](ParsedPath::parse) method.
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///
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/// This struct may be used like [`GetPath`] but removes the cost of parsing the path
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/// string at each element access.
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///
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/// It's recommended to use this in place of [`GetPath`] when the path string is
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/// unlikely to be changed and will be accessed repeatedly.
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///
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/// ## Examples
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///
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/// Parsing a [`&'static str`](str):
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/// ```
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/// # use bevy_reflect::ParsedPath;
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/// let my_static_string: &'static str = "bar#0.1[2].0";
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/// // Breakdown:
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/// // "bar" - Access struct field named "bar"
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/// // "#0" - Access struct field at index 0
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/// // ".1" - Access tuple struct field at index 1
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/// // "[2]" - Access list element at index 2
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/// // ".0" - Access tuple variant field at index 0
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/// let my_path = ParsedPath::parse_static(my_static_string);
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/// ```
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/// Parsing a non-static [`&str`](str):
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/// ```
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/// # use bevy_reflect::ParsedPath;
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/// let my_string = String::from("bar#0.1[2].0");
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/// // Breakdown:
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/// // "bar" - Access struct field named "bar"
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/// // "#0" - Access struct field at index 0
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/// // ".1" - Access tuple struct field at index 1
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/// // "[2]" - Access list element at index 2
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/// // ".0" - Access tuple variant field at index 0
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/// let my_path = ParsedPath::parse(&my_string);
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/// ```
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/// Manually constructing a [`ParsedPath`]:
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/// ```
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/// # use std::borrow::Cow;
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/// # use bevy_reflect::access::Access;
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/// # use bevy_reflect::ParsedPath;
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/// let path_elements = [
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/// Access::Field(Cow::Borrowed("bar")),
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/// Access::FieldIndex(0),
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/// Access::TupleIndex(1),
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/// Access::ListIndex(2),
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/// Access::TupleIndex(1),
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/// ];
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/// let my_path = ParsedPath::from(path_elements);
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/// ```
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#[derive(Clone, Debug, PartialEq, PartialOrd, Ord, Eq, Hash, From)]
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pub struct ParsedPath(
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/// This is a vector of pre-parsed [`OffsetAccess`]es.
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pub Vec<OffsetAccess>,
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);
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impl ParsedPath {
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/// Parses a [`ParsedPath`] from a string.
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///
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/// Returns an error if the string does not represent a valid path to an element.
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///
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/// The exact format for path strings can be found in the documentation for [`GetPath`].
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/// In short, though, a path consists of one or more chained accessor strings.
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/// These are:
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/// - Named field access (`.field`)
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/// - Unnamed field access (`.1`)
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/// - Field index access (`#0`)
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/// - Sequence access (`[2]`)
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///
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/// # Example
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/// ```
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/// # use bevy_reflect::{ParsedPath, Reflect, ReflectPath};
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/// #[derive(Reflect)]
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/// struct Foo {
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/// bar: Bar,
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/// }
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///
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/// #[derive(Reflect)]
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/// struct Bar {
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/// baz: Baz,
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/// }
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///
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/// #[derive(Reflect)]
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/// struct Baz(f32, Vec<Option<u32>>);
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///
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/// let foo = Foo {
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/// bar: Bar {
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/// baz: Baz(3.14, vec![None, None, Some(123)])
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/// },
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/// };
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///
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/// let parsed_path = ParsedPath::parse("bar#0.1[2].0").unwrap();
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/// // Breakdown:
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/// // "bar" - Access struct field named "bar"
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/// // "#0" - Access struct field at index 0
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/// // ".1" - Access tuple struct field at index 1
|
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/// // "[2]" - Access list element at index 2
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/// // ".0" - Access tuple variant field at index 0
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///
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/// assert_eq!(parsed_path.element::<u32>(&foo).unwrap(), &123);
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/// ```
|
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pub fn parse(string: &str) -> PathResult<Self> {
|
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let mut parts = Vec::new();
|
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for (access, offset) in PathParser::new(string) {
|
||
parts.push(OffsetAccess {
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access: access?.into_owned(),
|
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offset: Some(offset),
|
||
});
|
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}
|
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Ok(Self(parts))
|
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}
|
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|
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/// Similar to [`Self::parse`] but only works on `&'static str`
|
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/// and does not allocate per named field.
|
||
pub fn parse_static(string: &'static str) -> PathResult<'static, Self> {
|
||
let mut parts = Vec::new();
|
||
for (access, offset) in PathParser::new(string) {
|
||
parts.push(OffsetAccess {
|
||
access: access?,
|
||
offset: Some(offset),
|
||
});
|
||
}
|
||
Ok(Self(parts))
|
||
}
|
||
}
|
||
impl<'a> ReflectPath<'a> for &'a ParsedPath {
|
||
fn reflect_element(self, mut root: &dyn PartialReflect) -> PathResult<'a, &dyn PartialReflect> {
|
||
for OffsetAccess { access, offset } in &self.0 {
|
||
root = access.element(root, *offset)?;
|
||
}
|
||
Ok(root)
|
||
}
|
||
fn reflect_element_mut(
|
||
self,
|
||
mut root: &mut dyn PartialReflect,
|
||
) -> PathResult<'a, &mut dyn PartialReflect> {
|
||
for OffsetAccess { access, offset } in &self.0 {
|
||
root = access.element_mut(root, *offset)?;
|
||
}
|
||
Ok(root)
|
||
}
|
||
}
|
||
impl<const N: usize> From<[OffsetAccess; N]> for ParsedPath {
|
||
fn from(value: [OffsetAccess; N]) -> Self {
|
||
ParsedPath(value.to_vec())
|
||
}
|
||
}
|
||
impl From<Vec<Access<'static>>> for ParsedPath {
|
||
fn from(value: Vec<Access<'static>>) -> Self {
|
||
ParsedPath(
|
||
value
|
||
.into_iter()
|
||
.map(|access| OffsetAccess {
|
||
access,
|
||
offset: None,
|
||
})
|
||
.collect(),
|
||
)
|
||
}
|
||
}
|
||
impl<const N: usize> From<[Access<'static>; N]> for ParsedPath {
|
||
fn from(value: [Access<'static>; N]) -> Self {
|
||
value.to_vec().into()
|
||
}
|
||
}
|
||
|
||
impl<'a> TryFrom<&'a str> for ParsedPath {
|
||
type Error = ReflectPathError<'a>;
|
||
fn try_from(value: &'a str) -> Result<Self, Self::Error> {
|
||
ParsedPath::parse(value)
|
||
}
|
||
}
|
||
|
||
impl fmt::Display for ParsedPath {
|
||
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
|
||
for OffsetAccess { access, .. } in &self.0 {
|
||
write!(f, "{access}")?;
|
||
}
|
||
Ok(())
|
||
}
|
||
}
|
||
impl core::ops::Index<usize> for ParsedPath {
|
||
type Output = OffsetAccess;
|
||
fn index(&self, index: usize) -> &Self::Output {
|
||
&self.0[index]
|
||
}
|
||
}
|
||
impl core::ops::IndexMut<usize> for ParsedPath {
|
||
fn index_mut(&mut self, index: usize) -> &mut Self::Output {
|
||
&mut self.0[index]
|
||
}
|
||
}
|
||
|
||
#[cfg(test)]
|
||
#[allow(clippy::float_cmp, clippy::approx_constant)]
|
||
mod tests {
|
||
use super::*;
|
||
use crate as bevy_reflect;
|
||
use crate::*;
|
||
use alloc::vec;
|
||
|
||
#[derive(Reflect)]
|
||
struct A {
|
||
w: usize,
|
||
x: B,
|
||
y: Vec<C>,
|
||
z: D,
|
||
unit_variant: F,
|
||
tuple_variant: F,
|
||
struct_variant: F,
|
||
array: [i32; 3],
|
||
tuple: (bool, f32),
|
||
}
|
||
|
||
#[derive(Reflect)]
|
||
struct B {
|
||
foo: usize,
|
||
łørđ: C,
|
||
}
|
||
|
||
#[derive(Reflect)]
|
||
struct C {
|
||
mосква: f32,
|
||
}
|
||
|
||
#[derive(Reflect)]
|
||
struct D(E);
|
||
|
||
#[derive(Reflect)]
|
||
struct E(f32, usize);
|
||
|
||
#[derive(Reflect, PartialEq, Debug)]
|
||
enum F {
|
||
Unit,
|
||
Tuple(u32, u32),
|
||
Şķràźÿ { 東京: char },
|
||
}
|
||
|
||
fn a_sample() -> A {
|
||
A {
|
||
w: 1,
|
||
x: B {
|
||
foo: 10,
|
||
łørđ: C { mосква: 3.14 },
|
||
},
|
||
y: vec![C { mосква: 1.0 }, C { mосква: 2.0 }],
|
||
z: D(E(10.0, 42)),
|
||
unit_variant: F::Unit,
|
||
tuple_variant: F::Tuple(123, 321),
|
||
struct_variant: F::Şķràźÿ { 東京: 'm' },
|
||
array: [86, 75, 309],
|
||
tuple: (true, 1.23),
|
||
}
|
||
}
|
||
|
||
fn offset(access: Access<'static>, offset: usize) -> OffsetAccess {
|
||
OffsetAccess {
|
||
access,
|
||
offset: Some(offset),
|
||
}
|
||
}
|
||
|
||
fn access_field(field: &'static str) -> Access<'static> {
|
||
Access::Field(field.into())
|
||
}
|
||
|
||
type StaticError = ReflectPathError<'static>;
|
||
|
||
fn invalid_access(
|
||
offset: usize,
|
||
actual: ReflectKind,
|
||
expected: ReflectKind,
|
||
access: &'static str,
|
||
) -> StaticError {
|
||
ReflectPathError::InvalidAccess(AccessError {
|
||
kind: AccessErrorKind::IncompatibleTypes { actual, expected },
|
||
access: ParsedPath::parse_static(access).unwrap()[1].access.clone(),
|
||
offset: Some(offset),
|
||
})
|
||
}
|
||
|
||
#[test]
|
||
fn try_from() {
|
||
assert_eq!(
|
||
ParsedPath::try_from("w").unwrap().0,
|
||
&[offset(access_field("w"), 1)]
|
||
);
|
||
|
||
let r = ParsedPath::try_from("w[");
|
||
let matches = matches!(r, Err(ReflectPathError::ParseError { .. }));
|
||
assert!(
|
||
matches,
|
||
"ParsedPath::try_from did not return a ParseError for \"w[\""
|
||
);
|
||
}
|
||
|
||
#[test]
|
||
fn parsed_path_parse() {
|
||
assert_eq!(
|
||
ParsedPath::parse("w").unwrap().0,
|
||
&[offset(access_field("w"), 1)]
|
||
);
|
||
assert_eq!(
|
||
ParsedPath::parse("x.foo").unwrap().0,
|
||
&[offset(access_field("x"), 1), offset(access_field("foo"), 2)]
|
||
);
|
||
assert_eq!(
|
||
ParsedPath::parse("x.łørđ.mосква").unwrap().0,
|
||
&[
|
||
offset(access_field("x"), 1),
|
||
offset(access_field("łørđ"), 2),
|
||
offset(access_field("mосква"), 10)
|
||
]
|
||
);
|
||
assert_eq!(
|
||
ParsedPath::parse("y[1].mосква").unwrap().0,
|
||
&[
|
||
offset(access_field("y"), 1),
|
||
offset(Access::ListIndex(1), 2),
|
||
offset(access_field("mосква"), 5)
|
||
]
|
||
);
|
||
assert_eq!(
|
||
ParsedPath::parse("z.0.1").unwrap().0,
|
||
&[
|
||
offset(access_field("z"), 1),
|
||
offset(Access::TupleIndex(0), 2),
|
||
offset(Access::TupleIndex(1), 4),
|
||
]
|
||
);
|
||
assert_eq!(
|
||
ParsedPath::parse("x#0").unwrap().0,
|
||
&[
|
||
offset(access_field("x"), 1),
|
||
offset(Access::FieldIndex(0), 2)
|
||
]
|
||
);
|
||
assert_eq!(
|
||
ParsedPath::parse("x#0#1").unwrap().0,
|
||
&[
|
||
offset(access_field("x"), 1),
|
||
offset(Access::FieldIndex(0), 2),
|
||
offset(Access::FieldIndex(1), 4)
|
||
]
|
||
);
|
||
}
|
||
|
||
#[test]
|
||
fn parsed_path_get_field() {
|
||
let a = a_sample();
|
||
|
||
let b = ParsedPath::parse("w").unwrap();
|
||
let c = ParsedPath::parse("x.foo").unwrap();
|
||
let d = ParsedPath::parse("x.łørđ.mосква").unwrap();
|
||
let e = ParsedPath::parse("y[1].mосква").unwrap();
|
||
let f = ParsedPath::parse("z.0.1").unwrap();
|
||
let g = ParsedPath::parse("x#0").unwrap();
|
||
let h = ParsedPath::parse("x#1#0").unwrap();
|
||
let i = ParsedPath::parse("unit_variant").unwrap();
|
||
let j = ParsedPath::parse("tuple_variant.1").unwrap();
|
||
let k = ParsedPath::parse("struct_variant.東京").unwrap();
|
||
let l = ParsedPath::parse("struct_variant#0").unwrap();
|
||
let m = ParsedPath::parse("array[2]").unwrap();
|
||
let n = ParsedPath::parse("tuple.1").unwrap();
|
||
|
||
for _ in 0..30 {
|
||
assert_eq!(*b.element::<usize>(&a).unwrap(), 1);
|
||
assert_eq!(*c.element::<usize>(&a).unwrap(), 10);
|
||
assert_eq!(*d.element::<f32>(&a).unwrap(), 3.14);
|
||
assert_eq!(*e.element::<f32>(&a).unwrap(), 2.0);
|
||
assert_eq!(*f.element::<usize>(&a).unwrap(), 42);
|
||
assert_eq!(*g.element::<usize>(&a).unwrap(), 10);
|
||
assert_eq!(*h.element::<f32>(&a).unwrap(), 3.14);
|
||
assert_eq!(*i.element::<F>(&a).unwrap(), F::Unit);
|
||
assert_eq!(*j.element::<u32>(&a).unwrap(), 321);
|
||
assert_eq!(*k.element::<char>(&a).unwrap(), 'm');
|
||
assert_eq!(*l.element::<char>(&a).unwrap(), 'm');
|
||
assert_eq!(*m.element::<i32>(&a).unwrap(), 309);
|
||
assert_eq!(*n.element::<f32>(&a).unwrap(), 1.23);
|
||
}
|
||
}
|
||
|
||
#[test]
|
||
fn reflect_array_behaves_like_list() {
|
||
#[derive(Reflect)]
|
||
struct A {
|
||
list: Vec<u8>,
|
||
array: [u8; 10],
|
||
}
|
||
|
||
let a = A {
|
||
list: vec![0, 1, 2, 3, 4, 5, 6, 7, 8, 9],
|
||
array: [0, 1, 2, 3, 4, 5, 6, 7, 8, 9],
|
||
};
|
||
|
||
assert_eq!(*a.path::<u8>("list[5]").unwrap(), 5);
|
||
assert_eq!(*a.path::<u8>("array[5]").unwrap(), 5);
|
||
assert_eq!(*a.path::<u8>("list[0]").unwrap(), 0);
|
||
assert_eq!(*a.path::<u8>("array[0]").unwrap(), 0);
|
||
}
|
||
|
||
#[test]
|
||
fn reflect_array_behaves_like_list_mut() {
|
||
#[derive(Reflect)]
|
||
struct A {
|
||
list: Vec<u8>,
|
||
array: [u8; 10],
|
||
}
|
||
|
||
let mut a = A {
|
||
list: vec![0, 1, 2, 3, 4, 5, 6, 7, 8, 9],
|
||
array: [0, 1, 2, 3, 4, 5, 6, 7, 8, 9],
|
||
};
|
||
|
||
assert_eq!(*a.path_mut::<u8>("list[5]").unwrap(), 5);
|
||
assert_eq!(*a.path_mut::<u8>("array[5]").unwrap(), 5);
|
||
|
||
*a.path_mut::<u8>("list[5]").unwrap() = 10;
|
||
*a.path_mut::<u8>("array[5]").unwrap() = 10;
|
||
|
||
assert_eq!(*a.path_mut::<u8>("list[5]").unwrap(), 10);
|
||
assert_eq!(*a.path_mut::<u8>("array[5]").unwrap(), 10);
|
||
}
|
||
|
||
#[test]
|
||
fn reflect_path() {
|
||
let mut a = a_sample();
|
||
|
||
assert_eq!(*a.path::<usize>("w").unwrap(), 1);
|
||
assert_eq!(*a.path::<usize>("x.foo").unwrap(), 10);
|
||
assert_eq!(*a.path::<f32>("x.łørđ.mосква").unwrap(), 3.14);
|
||
assert_eq!(*a.path::<f32>("y[1].mосква").unwrap(), 2.0);
|
||
assert_eq!(*a.path::<usize>("z.0.1").unwrap(), 42);
|
||
assert_eq!(*a.path::<usize>("x#0").unwrap(), 10);
|
||
assert_eq!(*a.path::<f32>("x#1#0").unwrap(), 3.14);
|
||
|
||
assert_eq!(*a.path::<F>("unit_variant").unwrap(), F::Unit);
|
||
assert_eq!(*a.path::<u32>("tuple_variant.1").unwrap(), 321);
|
||
assert_eq!(*a.path::<char>("struct_variant.東京").unwrap(), 'm');
|
||
assert_eq!(*a.path::<char>("struct_variant#0").unwrap(), 'm');
|
||
|
||
assert_eq!(*a.path::<i32>("array[2]").unwrap(), 309);
|
||
|
||
assert_eq!(*a.path::<f32>("tuple.1").unwrap(), 1.23);
|
||
*a.path_mut::<f32>("tuple.1").unwrap() = 3.21;
|
||
assert_eq!(*a.path::<f32>("tuple.1").unwrap(), 3.21);
|
||
|
||
*a.path_mut::<f32>("y[1].mосква").unwrap() = 3.0;
|
||
assert_eq!(a.y[1].mосква, 3.0);
|
||
|
||
*a.path_mut::<u32>("tuple_variant.0").unwrap() = 1337;
|
||
assert_eq!(a.tuple_variant, F::Tuple(1337, 321));
|
||
|
||
assert_eq!(
|
||
a.reflect_path("x.notreal").err().unwrap(),
|
||
ReflectPathError::InvalidAccess(AccessError {
|
||
kind: AccessErrorKind::MissingField(ReflectKind::Struct),
|
||
access: access_field("notreal"),
|
||
offset: Some(2),
|
||
})
|
||
);
|
||
|
||
assert_eq!(
|
||
a.reflect_path("unit_variant.0").err().unwrap(),
|
||
ReflectPathError::InvalidAccess(AccessError {
|
||
kind: AccessErrorKind::IncompatibleEnumVariantTypes {
|
||
actual: VariantType::Unit,
|
||
expected: VariantType::Tuple,
|
||
},
|
||
access: ParsedPath::parse_static("unit_variant.0").unwrap()[1]
|
||
.access
|
||
.clone(),
|
||
offset: Some(13),
|
||
})
|
||
);
|
||
assert_eq!(
|
||
a.reflect_path("x[0]").err().unwrap(),
|
||
invalid_access(2, ReflectKind::Struct, ReflectKind::List, "x[0]")
|
||
);
|
||
assert_eq!(
|
||
a.reflect_path("y.x").err().unwrap(),
|
||
invalid_access(2, ReflectKind::List, ReflectKind::Struct, "y.x")
|
||
);
|
||
}
|
||
|
||
#[test]
|
||
fn accept_leading_tokens() {
|
||
assert_eq!(
|
||
ParsedPath::parse(".w").unwrap().0,
|
||
&[offset(access_field("w"), 1)]
|
||
);
|
||
assert_eq!(
|
||
ParsedPath::parse("#0.foo").unwrap().0,
|
||
&[
|
||
offset(Access::FieldIndex(0), 1),
|
||
offset(access_field("foo"), 3)
|
||
]
|
||
);
|
||
assert_eq!(
|
||
ParsedPath::parse(".5").unwrap().0,
|
||
&[offset(Access::TupleIndex(5), 1)]
|
||
);
|
||
assert_eq!(
|
||
ParsedPath::parse("[0].łørđ").unwrap().0,
|
||
&[
|
||
offset(Access::ListIndex(0), 1),
|
||
offset(access_field("łørđ"), 4)
|
||
]
|
||
);
|
||
}
|
||
}
|