Make get_mapped_range return a Result rather than panicking

Author: atlv24

CHANGELOG.md

@@ -53,6 +53,7 @@ Bottom level categories:
 #### General
 
 - `Features::CLIP_DISTANCE`, `naga::Capabilities::CLIP_DISTANCE`, and `naga::BuiltIn::ClipDistance` have been renamed to `CLIP_DISTANCES` and `ClipDistances` (viz., pluralized) as appropriate, to match the WebGPU spec. By @ErichDonGubler in [#9267](https://github.com/gfx-rs/wgpu/pull/9267).
+- `Buffer::get_mapped_range` and variants now return `Result<_, MapRangeError>>` instead of panicking, in line with WebGPU spec. By @atlv24 in [#9281](https://github.com/gfx-rs/wgpu/pull/9281).
 
 #### Validation
 

examples/features/src/big_compute_buffers/mod.rs

@@ -85,7 +85,7 @@ pub async fn execute_gpu_inner(
     let mut data = Vec::new();
     for staging_buffer in &staging_buffers {
         let slice = staging_buffer.slice(..);
-        let mapped = slice.get_mapped_range();
+        let mapped = slice.get_mapped_range().unwrap();
         data.extend_from_slice(bytemuck::cast_slice(&mapped));
         drop(mapped);
         staging_buffer.unmap();

examples/features/src/cooperative_matrix/mod.rs

@@ -411,7 +411,7 @@ async fn execute(
         .expect("Channel receive failed")
         .expect("Buffer mapping failed");
 
-    let data = buffer_slice.get_mapped_range();
+    let data = buffer_slice.get_mapped_range().unwrap();
 
     // Convert result back to f32 for comparison
     let result: Vec<f32> = if use_f16 {

examples/features/src/framework.rs

@@ -735,7 +735,7 @@ impl<E: Example + wgpu::WasmNotSendSync> From<ExampleTestParams<E>>
                 ctx.async_poll(wgpu::PollType::wait_indefinitely())
                     .await
                     .unwrap();
-                let bytes = dst_buffer_slice.get_mapped_range().to_vec();
+                let bytes = dst_buffer_slice.get_mapped_range().unwrap().to_vec();
 
                 wgpu_test::image::compare_image_output(
                     dbg!(env!("CARGO_MANIFEST_DIR").to_string() + "/../../" + params.image_path),

examples/features/src/hello_synchronization/mod.rs

@@ -184,7 +184,9 @@ async fn get_data<T: bytemuck::Pod>(
     buffer_slice.map_async(wgpu::MapMode::Read, move |r| sender.send(r).unwrap());
     device.poll(wgpu::PollType::wait_indefinitely()).unwrap();
     receiver.recv_async().await.unwrap().unwrap();
-    output.copy_from_slice(bytemuck::cast_slice(&buffer_slice.get_mapped_range()[..]));
+    output.copy_from_slice(bytemuck::cast_slice(
+        &buffer_slice.get_mapped_range().unwrap()[..],
+    ));
     staging_buffer.unmap();
 }
 

examples/features/src/hello_workgroups/mod.rs

@@ -173,7 +173,9 @@ async fn get_data<T: bytemuck::Pod>(
     buffer_slice.map_async(wgpu::MapMode::Read, move |r| sender.send(r).unwrap());
     device.poll(wgpu::PollType::wait_indefinitely()).unwrap();
     receiver.recv_async().await.unwrap().unwrap();
-    output.copy_from_slice(bytemuck::cast_slice(&buffer_slice.get_mapped_range()[..]));
+    output.copy_from_slice(bytemuck::cast_slice(
+        &buffer_slice.get_mapped_range().unwrap()[..],
+    ));
     staging_buffer.unmap();
 }
 

examples/features/src/mipmap/mod.rs

@@ -417,11 +417,13 @@ impl crate::framework::Example for Example {
             let timestamp_view = query_sets
                 .mapping_buffer
                 .slice(..size_of::<TimestampQueries>() as wgpu::BufferAddress)
-                .get_mapped_range();
+                .get_mapped_range()
+                .unwrap();
             let pipeline_stats_view = query_sets
                 .mapping_buffer
                 .slice(pipeline_statistics_offset()..)
-                .get_mapped_range();
+                .get_mapped_range()
+                .unwrap();
             // Convert the raw data into a useful structure
             let timestamp_data: &TimestampQueries = bytemuck::from_bytes(&timestamp_view);
             let pipeline_stats_data: &PipelineStatisticsQueries =

examples/features/src/render_to_texture/mod.rs

@@ -137,7 +137,7 @@ async fn run(_path: Option<String>) {
     receiver.recv_async().await.unwrap().unwrap();
     log::info!("Output buffer mapped.");
     {
-        let view = buffer_slice.get_mapped_range();
+        let view = buffer_slice.get_mapped_range().unwrap();
         texture_data.extend_from_slice(&view[..]);
     }
     log::info!("Image data copied to local.");

examples/features/src/repeated_compute/mod.rs

@@ -115,7 +115,7 @@ async fn compute(local_buffer: &mut [u32], context: &WgpuContext) {
     log::info!("Result received.");
     // NOW we can call get_mapped_range.
     {
-        let view = buffer_slice.get_mapped_range();
+        let view = buffer_slice.get_mapped_range().unwrap();
         local_buffer.copy_from_slice(bytemuck::cast_slice(&view));
     }
     log::info!("Results written to local buffer.");

examples/features/src/storage_texture/mod.rs

@@ -146,7 +146,7 @@ async fn run(_path: Option<String>) {
     receiver.recv_async().await.unwrap().unwrap();
     log::info!("Output buffer mapped");
     {
-        let view = buffer_slice.get_mapped_range();
+        let view = buffer_slice.get_mapped_range().unwrap();
         texture_data.copy_from_slice(&view[..]);
     }
     log::info!("GPU data copied to local.");