Don't implement Hash on handle id types for wasm32

Unlike the native handle ids that are effectively wrappers around
an intetger type, the handle id types for the wasm32 backend are redefined
to point at web_sys structures that may not have Hash implemented.

Author: aloucks

src/lib.rs

@@ -99,7 +99,8 @@ impl std::hash::Hash for Temp {
 ///
 /// An `Adapter` can be used to open a connection to the corresponding device on the host system,
 /// yielding a [`Device`] object.
-#[derive(Debug, PartialEq, Eq, Hash)]
+#[derive(Debug, PartialEq, Eq)]
+#[cfg_attr(not(target_arch = "wasm32"), derive(Hash))]
 pub struct Adapter {
     id: wgc::id::AdapterId,
 }
@@ -117,7 +118,8 @@ pub struct RequestAdapterOptions<'a> {
 ///
 /// The `Device` is the responsible for the creation of most rendering and compute resources, as
 /// well as exposing [`Queue`] objects.
-#[derive(Debug, PartialEq, Eq, Hash)]
+#[derive(Debug, PartialEq, Eq)]
+#[cfg_attr(not(target_arch = "wasm32"), derive(Hash))]
 pub struct Device {
     id: wgc::id::DeviceId,
     temp: Temp,
@@ -132,14 +134,16 @@ pub enum Maintain {
 }
 
 /// A handle to a GPU-accessible buffer.
-#[derive(Debug, PartialEq, Eq, Hash)]
+#[derive(Debug, PartialEq, Eq)]
+#[cfg_attr(not(target_arch = "wasm32"), derive(Hash))]
 pub struct Buffer {
     id: wgc::id::BufferId,
     device_id: wgc::id::DeviceId,
 }
 
 /// A handle to a texture on the GPU.
-#[derive(Debug, PartialEq, Eq, Hash)]
+#[derive(Debug, PartialEq, Eq)]
+#[cfg_attr(not(target_arch = "wasm32"), derive(Hash))]
 pub struct Texture {
     id: wgc::id::TextureId,
     owned: bool,
@@ -149,7 +153,8 @@ pub struct Texture {
 ///
 /// A `TextureView` object describes a texture and associated metadata needed by a
 /// [`RenderPipeline`] or [`BindGroup`].
-#[derive(Debug, PartialEq, Eq, Hash)]
+#[derive(Debug, PartialEq, Eq)]
+#[cfg_attr(not(target_arch = "wasm32"), derive(Hash))]
 pub struct TextureView {
     id: wgc::id::TextureViewId,
     owned: bool,
@@ -160,7 +165,8 @@ pub struct TextureView {
 /// A `Sampler` object defines how a pipeline will sample from a [`TextureView`]. Samplers define
 /// image filters (including anisotropy) and address (wrapping) modes, among other things. See
 /// the documentation for [`SamplerDescriptor`] for more information.
-#[derive(Debug, PartialEq, Eq, Hash)]
+#[derive(Debug, PartialEq, Eq)]
+#[cfg_attr(not(target_arch = "wasm32"), derive(Hash))]
 pub struct Sampler {
     id: wgc::id::SamplerId,
 }
@@ -169,7 +175,8 @@ pub struct Sampler {
 ///
 /// A `Surface` represents a platform-specific surface (e.g. a window) to which rendered images may
 /// be presented. A `Surface` may be created with [`Surface::create`].
-#[derive(Debug, PartialEq)]
+#[derive(Debug, PartialEq, Eq)]
+#[cfg_attr(not(target_arch = "wasm32"), derive(Hash))]
 pub struct Surface {
     id: wgc::id::SurfaceId,
 }
@@ -178,7 +185,8 @@ pub struct Surface {
 ///
 /// A `SwapChain` represents the image or series of images that will be presented to a [`Surface`].
 /// A `SwapChain` may be created with [`Device::create_swap_chain`].
-#[derive(Debug, PartialEq)]
+#[derive(Debug, PartialEq, Eq)]
+#[cfg_attr(not(target_arch = "wasm32"), derive(Hash))]
 pub struct SwapChain {
     id: wgc::id::SwapChainId,
 }
@@ -189,7 +197,8 @@ pub struct SwapChain {
 /// create a [`BindGroupDescriptor`] object, which in turn can be used to create a [`BindGroup`]
 /// object with [`Device::create_bind_group`]. A series of `BindGroupLayout`s can also be used to
 /// create a [`PipelineLayoutDescriptor`], which can be used to create a [`PipelineLayout`].
-#[derive(Debug, PartialEq, Eq, Hash)]
+#[derive(Debug, PartialEq, Eq)]
+#[cfg_attr(not(target_arch = "wasm32"), derive(Hash))]
 pub struct BindGroupLayout {
     id: wgc::id::BindGroupLayoutId,
 }
@@ -200,7 +209,8 @@ pub struct BindGroupLayout {
 /// [`BindGroupLayout`]. It can be created with [`Device::create_bind_group`]. A `BindGroup` can
 /// be bound to a particular [`RenderPass`] with [`RenderPass::set_bind_group`], or to a
 /// [`ComputePass`] with [`ComputePass::set_bind_group`].
-#[derive(Debug, PartialEq, Eq, Hash)]
+#[derive(Debug, PartialEq, Eq)]
+#[cfg_attr(not(target_arch = "wasm32"), derive(Hash))]
 pub struct BindGroup {
     id: wgc::id::BindGroupId,
 }
@@ -216,15 +226,17 @@ impl Drop for BindGroup {
 /// A `ShaderModule` represents a compiled shader module on the GPU. It can be created by passing
 /// valid SPIR-V source code to [`Device::create_shader_module`]. Shader modules are used to define
 /// programmable stages of a pipeline.
-#[derive(Debug, PartialEq, Eq, Hash)]
+#[derive(Debug, PartialEq, Eq)]
+#[cfg_attr(not(target_arch = "wasm32"), derive(Hash))]
 pub struct ShaderModule {
     id: wgc::id::ShaderModuleId,
 }
 
 /// An opaque handle to a pipeline layout.
 ///
 /// A `PipelineLayout` object describes the available binding groups of a pipeline.
-#[derive(Debug, PartialEq, Eq, Hash)]
+#[derive(Debug, PartialEq, Eq)]
+#[cfg_attr(not(target_arch = "wasm32"), derive(Hash))]
 pub struct PipelineLayout {
     id: wgc::id::PipelineLayoutId,
 }
@@ -233,13 +245,15 @@ pub struct PipelineLayout {
 ///
 /// A `RenderPipeline` object represents a graphics pipeline and its stages, bindings, vertex
 /// buffers and targets. A `RenderPipeline` may be created with [`Device::create_render_pipeline`].
-#[derive(Debug, PartialEq)]
+#[derive(Debug, PartialEq, Eq)]
+#[cfg_attr(not(target_arch = "wasm32"), derive(Hash))]
 pub struct RenderPipeline {
     id: wgc::id::RenderPipelineId,
 }
 
 /// A handle to a compute pipeline.
-#[derive(Debug, PartialEq)]
+#[derive(Debug, PartialEq, Eq)]
+#[cfg_attr(not(target_arch = "wasm32"), derive(Hash))]
 pub struct ComputePipeline {
     id: wgc::id::ComputePipelineId,
 }
@@ -249,7 +263,8 @@ pub struct ComputePipeline {
 /// A `CommandBuffer` represents a complete sequence of commands that may be submitted to a command
 /// queue with [`Queue::submit`]. A `CommandBuffer` is obtained by recording a series of commands to
 /// a [`CommandEncoder`] and then calling [`CommandEncoder::finish`].
-#[derive(Debug, PartialEq, Eq, Hash)]
+#[derive(Debug, PartialEq, Eq)]
+#[cfg_attr(not(target_arch = "wasm32"), derive(Hash))]
 pub struct CommandBuffer {
     id: wgc::id::CommandBufferId,
 }
@@ -261,7 +276,8 @@ pub struct CommandBuffer {
 ///
 /// When finished recording, call [`CommandEncoder::finish`] to obtain a [`CommandBuffer`] which may
 /// be submitted for execution.
-#[derive(Debug, PartialEq, Eq, Hash)]
+#[derive(Debug, PartialEq, Eq)]
+#[cfg_attr(not(target_arch = "wasm32"), derive(Hash))]
 pub struct CommandEncoder {
     id: wgc::id::CommandEncoderId,
     /// This type should be !Send !Sync, because it represents an allocation on this thread's
@@ -286,7 +302,8 @@ pub struct ComputePass<'a> {
 /// A handle to a command queue on a device.
 ///
 /// A `Queue` executes recorded [`CommandBuffer`] objects.
-#[derive(Debug, PartialEq)]
+#[derive(Debug, PartialEq, Eq)]
+#[cfg_attr(not(target_arch = "wasm32"), derive(Hash))]
 pub struct Queue {
     id: wgc::id::QueueId,
 }