diff --git a/src/webgpu/api/validation/compute_pipeline.spec.ts b/src/webgpu/api/validation/compute_pipeline.spec.ts
index c552fed50af8..3a0a51b363c6 100644
--- a/src/webgpu/api/validation/compute_pipeline.spec.ts
+++ b/src/webgpu/api/validation/compute_pipeline.spec.ts
@@ -233,7 +233,7 @@ Tests calling createComputePipeline(Async) validation for compute workgroup_size
         [1, 1, 63],
         [1, 1, 64],
         [1, 1, 65],
-      ])
+      ] as const)
   )
   .fn(t => {
     const { isAsync, size } = t.params;
@@ -251,13 +251,14 @@ Tests calling createComputePipeline(Async) validation for compute workgroup_size
       },
     };
 
-    size[1] = size[1] ?? 1;
-    size[2] = size[2] ?? 1;
+    const workgroupX = size[0];
+    const workgroupY = size[1] ?? 1;
+    const workgroupZ = size[2] ?? 1;
 
     const _success =
-      size[0] <= t.device.limits.maxComputeWorkgroupSizeX &&
-      size[1] <= t.device.limits.maxComputeWorkgroupSizeY &&
-      size[2] <= t.device.limits.maxComputeWorkgroupSizeZ;
+      workgroupX <= t.device.limits.maxComputeWorkgroupSizeX &&
+      workgroupY <= t.device.limits.maxComputeWorkgroupSizeY &&
+      workgroupZ <= t.device.limits.maxComputeWorkgroupSizeZ;
     t.doCreateComputePipelineTest(isAsync, _success, descriptor);
   });