Add createBindGroupLayout test for exactly one binding type

src/webgpu/api/validation/createBindGroupLayout.spec.ts

@@ -524,3 +524,36 @@ g.test('storage_texture,formats')
       });
     }, !success);
   });
+
+const BINDINGS_OF_TYPES: BGLEntry[] = [
+  {},
+  { buffer: { type: 'uniform' } },
+  { sampler: { type: 'comparison' } },
+  { texture: { multisampled: false, sampleType: 'unfilterable-float' } },
+  { storageTexture: { access: 'read-only', format: 'r32uint' } },
+];
+
+g.test('binding_type')
+  .desc(
+    `
+    Test that exactly one of the binding types is specified for each entry.
+    - Test each type of bind group resource.
+    - Test that a validation error is generated if more than one type is specified.
+    - Test that a validation error is generated if no type is specified.
+    `
+  )
+  .params(u => u.combine('entry1', BINDINGS_OF_TYPES).combine('entry2', BINDINGS_OF_TYPES))
+  .fn(t => {
+    const { entry1, entry2 } = t.params;
+
+    const joined = { ...entry1, ...entry2 };
+
+    t.expectValidationError(
+      () => {
+        t.device.createBindGroupLayout({
+          entries: [{ binding: 0, visibility: GPUShaderStage.VERTEX, ...joined }],
+        });
+      },
+      !(Object.keys(joined).length === 1)
+    );
+  });