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+++ b/testing/web-platform/tests/webaudio/the-audio-api/the-audiobuffersourcenode-interface/sub-sample-buffer-stitching.html
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+<!doctype html>
+<html>
+  <head>
+    <title>
+      Test Sub-Sample Accurate Stitching of ABSNs
+    </title>
+    <script src="/resources/testharness.js"></script>
+    <script src="/resources/testharnessreport.js"></script>
+    <script src="/webaudio/resources/audit-util.js"></script>
+    <script src="/webaudio/resources/audit.js"></script>
+  </head>
+  <body>
+    <script>
+      let audit = Audit.createTaskRunner();
+
+      audit.define(
+          {
+            label: 'buffer-stitching-1',
+            description: 'Subsample buffer stitching, same rates'
+          },
+          (task, should) => {
+            const sampleRate = 44100;
+            const bufferRate = 44100;
+            const bufferLength = 30;
+
+            // Experimentally determined thresholds.  DO NOT relax these values
+            // to far from these values to make the tests pass.
+            const errorThreshold = 9.0957e-5;
+            const snrThreshold = 85.580;
+
+            // Informative message
+            should(sampleRate, 'Test 1: context.sampleRate')
+                .beEqualTo(sampleRate);
+            testBufferStitching(sampleRate, bufferRate, bufferLength)
+                .then(resultBuffer => {
+                  const actual = resultBuffer.getChannelData(0);
+                  const expected = resultBuffer.getChannelData(1);
+                  should(
+                      actual,
+                      `Stitched sine-wave buffers at sample rate ${bufferRate}`)
+                      .beCloseToArray(
+                          expected, {absoluteThreshold: errorThreshold});
+                  const SNR = 10 * Math.log10(computeSNR(actual, expected));
+                  should(SNR, `SNR (${SNR} dB)`)
+                      .beGreaterThanOrEqualTo(snrThreshold);
+                })
+                .then(() => task.done());
+          });
+
+      audit.define(
+          {
+            label: 'buffer-stitching-2',
+            description: 'Subsample buffer stitching, different rates'
+          },
+          (task, should) => {
+            const sampleRate = 44100;
+            const bufferRate = 43800;
+            const bufferLength = 30;
+
+            // Experimentally determined thresholds.  DO NOT relax these values
+            // to far from these values to make the tests pass.
+            const errorThreshold = 3.8986e-3;
+            const snrThreshold = 65.737;
+
+            // Informative message
+            should(sampleRate, 'Test 2: context.sampleRate')
+                .beEqualTo(sampleRate);
+            testBufferStitching(sampleRate, bufferRate, bufferLength)
+                .then(resultBuffer => {
+                  const actual = resultBuffer.getChannelData(0);
+                  const expected = resultBuffer.getChannelData(1);
+                  should(
+                      actual,
+                      `Stitched sine-wave buffers at sample rate ${bufferRate}`)
+                      .beCloseToArray(
+                          expected, {absoluteThreshold: errorThreshold});
+                  const SNR = 10 * Math.log10(computeSNR(actual, expected));
+                  should(SNR, `SNR (${SNR} dB)`)
+                      .beGreaterThanOrEqualTo(snrThreshold);
+                })
+                .then(() => task.done());
+          });
+
+      audit.run();
+
+      // Create graph to test stitching of consecutive ABSNs.  The context rate
+      // is |sampleRate|, and the buffers have a fixed length of |bufferLength|
+      // and rate of |bufferRate|.  The |bufferRate| should not be too different
+      // from |sampleRate| because of interpolation of the buffer to the context
+      // rate.
+      function testBufferStitching(sampleRate, bufferRate, bufferLength) {
+        // The context for testing.  Channel 0 contains the output from
+        // stitching all the buffers together, and channel 1 contains the
+        // expected output.
+        const context = new OfflineAudioContext(
+            {numberOfChannels: 2, length: sampleRate, sampleRate: sampleRate});
+
+        const merger = new ChannelMergerNode(
+            context, {numberOfInputs: context.destination.channelCount});
+
+        merger.connect(context.destination);
+
+        // The reference is a sine wave at 440 Hz.
+        const ref = new OscillatorNode(context, {frequency: 440, type: 'sine'});
+        ref.connect(merger, 0, 1);
+        ref.start();
+
+        // The test signal is a bunch of short AudioBufferSources containing
+        // bits of a sine wave.
+        let waveSignal = new Float32Array(context.length);
+        const omega = 2 * Math.PI / bufferRate * ref.frequency.value;
+        for (let k = 0; k < context.length; ++k) {
+          waveSignal[k] = Math.sin(omega * k);
+        }
+
+        // Slice the sine wave into many little buffers to be assigned to ABSNs
+        // that are started at the appropriate times to produce a final sine
+        // wave.
+        for (let k = 0; k < context.length; k += bufferLength) {
+          const buffer =
+              new AudioBuffer({length: bufferLength, sampleRate: bufferRate});
+          buffer.copyToChannel(waveSignal.slice(k, k + bufferLength), 0);
+
+          const src = new AudioBufferSourceNode(context, {buffer: buffer});
+          src.connect(merger, 0, 0);
+          src.start(k / bufferRate);
+        }
+
+        return context.startRendering();
+      }
+    </script>
+  </body>
+</html>