testing/web-platform/tests/serial/serialPort_loopback_BreakError-manual.https.html

   1 <!DOCTYPE html>
   2 <html>
   3   <head>
   4     <meta charset="utf-8">
   5     <title></title>
   6     <script src="/resources/testharness.js"></script>
   7     <script src="/resources/testharnessreport.js"></script>
   8     <script src="resources/common.js"></script>
   9     <script src="resources/manual.js"></script>
  10   </head>
  11   <body>
  12     <p>
  13       These tests require a connected serial device configured to act as a
  14       "loopback" device, with the transmit and receive pins wired together.
  15     </p>
  16     <script>
  17       manual_serial_test(async (t, port) => {
  18         await port.open({baudRate: 115200, bufferSize: 1024});
  19
  20         let reader = port.readable.getReader();
  21         let readPromise = (async () => {
  22           // A single zero byte will be read before the break is detected.
  23           const {value, done} = await reader.read();
  24           compareArrays(value, new Uint8Array([0]));
  25           assert_false(done);
  26
  27           try {
  28             const {value, done} = await reader.read();
  29             assert_unreached(`Expected break, got ${value.byteLength} bytes`);
  30           } catch (e) {
  31             assert_equals(e.constructor, DOMException);
  32             assert_equals(e.name, 'BreakError');
  33           }
  34         })();
  35
  36         await port.setSignals({break: true});
  37         await readPromise;
  38         await port.setSignals({break: false});
  39
  40         const writer = port.writable.getWriter();
  41         // |data| is small enough to be completely transmitted.
  42         let data = new Uint8Array([1, 2, 3, 4, 5, 6, 7, 8]);
  43         await writer.write(data);
  44         writer.releaseLock();
  45
  46         reader = port.readable.getReader();
  47         const buffer = await readWithLength(reader, data.byteLength);;
  48         compareArrays(buffer, data);
  49         reader.releaseLock();
  50
  51         await port.close();
  52       }, 'Break is detected.');
  53     </script>
  54   </body>
  55 </html>