1 files changed, 48 insertions, 0 deletions
diff --git a/testing/web-platform/tests/webaudio/the-audio-api/the-audioparam-interface/setValueAtTime-within-block.html b/testing/web-platform/tests/webaudio/the-audio-api/the-audioparam-interface/setValueAtTime-within-block.html
new file mode 100644
index 0000000000..36fde2b996
--- /dev/null
+++ b/testing/web-platform/tests/webaudio/the-audio-api/the-audioparam-interface/setValueAtTime-within-block.html
@@ -0,0 +1,48 @@
+<!DOCTYPE html>
+<title>Test setValueAtTime with start time not on a block boundary</title>
+<script src="/resources/testharness.js"></script>
+<script src="/resources/testharnessreport.js"></script>
+<script>
+promise_test(function() {
+  const bufferSize = 200;
+  const offset = 65;
+  const sampleRate = 48000;
+  const scheduledValue = -2.0;
+
+  var context = new OfflineAudioContext(1, bufferSize, sampleRate);
+
+  var gain = context.createGain();
+  gain.gain.setValueAtTime(scheduledValue, offset/sampleRate);
+  gain.connect(context.destination);
+
+  // Apply unit DC signal to gain node.
+  var source = context.createBufferSource();
+  source.buffer =
+    function() {
+      var buffer = context.createBuffer(1, 1, context.sampleRate);
+      buffer.getChannelData(0)[0] = 1.0;
+      return buffer;
+    }();
+  source.loop = true;
+  source.start();
+  source.connect(gain);
+
+  return context.startRendering().
+    then(function(buffer) {
+      assert_equals(buffer.length, bufferSize, "output buffer length");
+      var output = buffer.getChannelData(0);
+      var i = 0;
+      for (; i < offset; ++i) {
+        // "Its default value is 1."
+        assert_equals(output[i], 1.0, "default gain at sample " + i);
+      }
+      for (; i < buffer.length; ++i) {
+        // "If there are no more events after this SetValue event, then for
+        // t≥T0, v(t)=V, where T0 is the startTime parameter and V is the
+        // value parameter."
+        assert_equals(output[i], scheduledValue,
+                      "scheduled value at sample " + i);
+      }
+    });
+});
+</script>