Test for use of staging buffer in writeTexture (#7963)

Author: andyleiserson

tests/tests/wgpu-gpu/write_texture.rs

@@ -1,5 +1,6 @@
 //! Tests for texture copy
 
+use wgpu::*;
 use wgpu_test::{gpu_test, GpuTestConfiguration};
 
 #[gpu_test]
@@ -228,3 +229,109 @@ static WRITE_TEXTURE_NO_OOB: GpuTestConfiguration =
             },
         );
     });
+
+// Test a writeTexture operation that will use the staging buffer.
+// If run with the address sanitizer, this serves as a regression
+// test for https://github.com/gfx-rs/wgpu/pull/7893.
+#[gpu_test]
+static WRITE_TEXTURE_VIA_STAGING_BUFFER: GpuTestConfiguration = GpuTestConfiguration::new()
+    .run_async(|ctx| async move {
+        let width = 89;
+        let height = 17;
+
+        let tex = ctx.device.create_texture(&TextureDescriptor {
+            label: None,
+            dimension: TextureDimension::D2,
+            size: Extent3d {
+                width,
+                height,
+                depth_or_array_layers: 1,
+            },
+            format: TextureFormat::R8Uint,
+            usage: TextureUsages::COPY_DST
+                | TextureUsages::COPY_SRC
+                | TextureUsages::TEXTURE_BINDING,
+            mip_level_count: 1,
+            sample_count: 1,
+            view_formats: &[],
+        });
+
+        let write_width: u32 = 31;
+        let write_height: u32 = 5;
+        let write_bytes_per_row: u32 = 113;
+        let write_data = (0..(write_height - 1) * write_bytes_per_row + write_width)
+            .map(|b| (b % 256) as u8)
+            .collect::<Vec<_>>();
+
+        ctx.queue.write_texture(
+            TexelCopyTextureInfo {
+                texture: &tex,
+                mip_level: 0,
+                origin: Origin3d::ZERO,
+                aspect: TextureAspect::All,
+            },
+            &write_data,
+            TexelCopyBufferLayout {
+                offset: 0,
+                bytes_per_row: Some(write_bytes_per_row),
+                rows_per_image: Some(19),
+            },
+            Extent3d {
+                width: write_width,
+                height: write_height,
+                depth_or_array_layers: 1,
+            },
+        );
+
+        ctx.queue.submit(None);
+
+        let read_bytes_per_row = wgt::COPY_BYTES_PER_ROW_ALIGNMENT;
+        let read_buffer = ctx.device.create_buffer(&BufferDescriptor {
+            label: None,
+            size: (height * read_bytes_per_row) as u64,
+            usage: BufferUsages::MAP_READ | wgpu::BufferUsages::COPY_DST,
+            mapped_at_creation: false,
+        });
+
+        let mut encoder = ctx
+            .device
+            .create_command_encoder(&CommandEncoderDescriptor { label: None });
+
+        encoder.copy_texture_to_buffer(
+            TexelCopyTextureInfo {
+                texture: &tex,
+                mip_level: 0,
+                origin: Origin3d::ZERO,
+                aspect: TextureAspect::All,
+            },
+            TexelCopyBufferInfo {
+                buffer: &read_buffer,
+                layout: TexelCopyBufferLayout {
+                    offset: 0,
+                    bytes_per_row: Some(read_bytes_per_row),
+                    rows_per_image: Some(height),
+                },
+            },
+            Extent3d {
+                width,
+                height,
+                depth_or_array_layers: 1,
+            },
+        );
+
+        ctx.queue.submit(Some(encoder.finish()));
+
+        let slice = read_buffer.slice(..);
+        slice.map_async(MapMode::Read, |_| ());
+        ctx.async_poll(PollType::wait()).await.unwrap();
+        let read_data: Vec<u8> = slice.get_mapped_range().to_vec();
+
+        for x in 0..write_width {
+            for y in 0..write_height {
+                assert_eq!(
+                    read_data[(y * read_bytes_per_row + x) as usize],
+                    write_data[(y * write_bytes_per_row + x) as usize]
+                );
+            }
+        }
+    });