dom/webgpu/crashtests/1907222_truncate_error.html

   1 <!DOCTYPE html>
   2 <html class="reftest-wait">
   3   <head>
   4     <meta charset="utf-8" />
   5     <script src="/tests/SimpleTest/SimpleTest.js"></script>
   6     <link rel="stylesheet" href="/tests/SimpleTest/test.css" />
   7   </head>
   8   <body>
   9     <script>
  10       // Ensure that, when WebGPU generates an error message that is later
  11       // truncated by `wgpu_bindings::error::ErrorBuffer::init`, that
  12       // truncation always produces valid UTF-8, even when the error contains
  13       // multi-byte encodings.
  14       async function truncate_error_messages() {
  15         // The specific error we'll try to provoke is submitting a command
  16         // buffer to the wrong device's queue.
  17         const adapter = await navigator.gpu.requestAdapter();
  18         const device1 = await adapter.requestDevice();
  19         const device2 = await adapter.requestDevice();
  20
  21         // Try a range of label lengths (578±200, where 578 is the length that
  22         // tickles the original bug), searching for one that, when combined with
  23         // the error message and then truncated at whatever error message byte
  24         // length limit Firefox is imposing, will produce invalid UTF-8.
  25         //
  26         // Use a label containing n space characters followed by a crab emoji,
  27         // U+1F980, which requires four bytes to encode in UTF-8. Since this has
  28         // a four-byte encoding at the end, we only need to try every third
  29         // length to ensure we will always try a truncation point in the midst
  30         // of that encoding.
  31         for (let len = 378; len < 778; len += 3) {
  32           const label = ' '.repeat(len) + '\uD83E\uDD80';
  33           const encoder = device1.createCommandEncoder({ label });
  34           const command_buffer = encoder.finish();
  35
  36           // We don't want an error scope around this, because what makes
  37           // Firefox notice the bad UTF-8 is attempting to log the uncaught
  38           // WebGPU error as a warning.
  39           device2.queue.submit([command_buffer]);
  40         }
  41       }
  42
  43       truncate_error_messages()
  44         .catch(e => {
  45           console.log(e);
  46         })
  47         .finally(() => {
  48           // End the crashtest.
  49           document.documentElement.removeAttribute("class");
  50         });
  51     </script>
  52   </body>
  53 </html>