AudioBufferSourceNode loop duration should be the actual duration

LayoutTests/webaudio/audiobuffersource-loop-comprehensive.html

Index: LayoutTests/webaudio/audiobuffersource-loop-comprehensive.html
diff --git a/LayoutTests/webaudio/audiobuffersource-loop-comprehensive.html b/LayoutTests/webaudio/audiobuffersource-loop-comprehensive.html
index 1ff7132db8e641e923f371c1531548bd65e4cd28..1ddb02073c7279d0bea8418fbea25ab9815de685 100644
--- a/LayoutTests/webaudio/audiobuffersource-loop-comprehensive.html
+++ b/LayoutTests/webaudio/audiobuffersource-loop-comprehensive.html
@@ -23,70 +23,128 @@ description("Tests AudioBufferSourceNode looping with a variety of loop points."
 var tests = [
 
 { description: "loop whole buffer by default with loopStart == loopEnd == 0",
-  loopStartFrame: 0, loopEndFrame: 0, renderFrames: 16, playbackRate: 1,
+  loopStartFrame: 0,
+  loopEndFrame: 0,
+  renderFrames: 16,
+  playbackRate: 1,
   expected: [0,1,2,3,4,5,6,7,0,1,2,3,4,5,6,7] },
 
 { description: "loop whole buffer explicitly",
-  loopStartFrame: 0, loopEndFrame: 8, renderFrames: 16, playbackRate: 1,
+  loopStartFrame: 0,
+  loopEndFrame: 8,
+  renderFrames: 16,
+  playbackRate: 1,
   expected: [0,1,2,3,4,5,6,7,0,1,2,3,4,5,6,7] },
 
 { description: "loop from middle to end of buffer",
-  loopStartFrame: 4, loopEndFrame: 8, renderFrames: 16, playbackRate: 1,
+  loopStartFrame: 4,
+  loopEndFrame: 8,
+  renderFrames: 16,
+  playbackRate: 1,
   expected: [0,1,2,3,4,5,6,7,4,5,6,7,4,5,6,7] },
 
 { description: "loop from start to middle of buffer",
-  loopStartFrame: 0, loopEndFrame: 4, renderFrames: 16, playbackRate: 1,
+  loopStartFrame: 0,
+  loopEndFrame: 4,
+  renderFrames: 16,
+  playbackRate: 1,
   expected: [0,1,2,3,0,1,2,3,0,1,2,3,0,1,2,3] },
 
-{ loopStartFrame: 4, loopEndFrame: 6, renderFrames: 16, playbackRate: 1,
+{ loopStartFrame: 4,
+  loopEndFrame: 6,
+  renderFrames: 16,
+  playbackRate: 1,
   expected: [0,1,2,3,4,5,4,5,4,5,4,5,4,5,4,5] },
 
-{ loopStartFrame: 3, loopEndFrame: 7, renderFrames: 16, playbackRate: 1,
+{ loopStartFrame: 3,
+  loopEndFrame: 7,
+  renderFrames: 16,
+  playbackRate: 1,
   expected: [0,1,2,3,4,5,6,3,4,5,6,3,4,5,6,3] },
 
-{ loopStartFrame: 4, loopEndFrame: 6, renderFrames: 16, playbackRate: 0.5,
+{ loopStartFrame: 4,
+  loopEndFrame: 6,
+  renderFrames: 16,
+  playbackRate: 0.5,
   expected: [0, 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 4.5, 5, 5.5, 4, 4.5, 5, 5.5] },
 
-{ loopStartFrame: 4, loopEndFrame: 6, renderFrames: 16, playbackRate: 1.5,
+{ loopStartFrame: 4,
+  loopEndFrame: 6,
+  renderFrames: 16,
+  playbackRate: 1.5,
   expected: [0, 1.5, 3, 4.5, 4, 5.5, 5, 4.5, 4, 5.5, 5, 4.5, 4, 5.5, 5, 4.5] },
 
 // Offset past loop end, so playback starts at loop start      
-{ loopStartFrame: 2, loopEndFrame: 5, renderFrames: 16, playbackRate: 1,
+{ loopStartFrame: 2,
+  loopEndFrame: 5,
+  renderFrames: 16,
+  playbackRate: 1,
   offsetFrame: 6,
   expected: [2, 3, 4, 2, 3, 4, 2, 3, 4, 2, 3, 4, 2, 3, 4, 2] },
     
 // Offset before loop start, so start at offset and continue
-{ loopStartFrame: 3, loopEndFrame: 6, renderFrames: 16, playbackRate: 1,
+{ loopStartFrame: 3,
+  loopEndFrame: 6,
+  renderFrames: 16,
+  playbackRate: 1,
   offsetFrame: 1,
   expected: [1, 2, 3, 4, 5, 3, 4, 5, 3, 4, 5, 3, 4, 5, 3, 4] },
     
 // Offset between loop start and loop end, so start at offset and continue
-{ loopStartFrame: 3, loopEndFrame: 6, renderFrames: 16, playbackRate: 1,
+{ loopStartFrame: 3,
+  loopEndFrame: 6,
+  renderFrames: 16,
+  playbackRate: 1,
   offsetFrame: 4,
   expected: [4, 5, 3, 4, 5, 3, 4, 5, 3, 4, 5, 3, 4, 5, 3, 4] },
     
 { description: "illegal playbackRate of 47 greater than loop length",
-  loopStartFrame: 4, loopEndFrame: 6, renderFrames: 16, playbackRate: 47,
+  loopStartFrame: 4,
+  loopEndFrame: 6,
+  renderFrames: 16,
+  playbackRate: 47,
   expected: [0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0] },
 
 // Try illegal loop-points - they should be ignored and we'll loop the whole buffer.
 
 { description: "illegal loop: loopStartFrame > loopEndFrame",
-  loopStartFrame: 7, loopEndFrame: 3, renderFrames: 16, playbackRate: 1,
+  loopStartFrame: 7,
+  loopEndFrame: 3,
+  renderFrames: 16,
+  playbackRate: 1,
   expected: [0,1,2,3,4,5,6,7,0,1,2,3,4,5,6,7] },
 
 { description: "illegal loop: loopStartFrame == loopEndFrame",
-  loopStartFrame: 3, loopEndFrame: 3, renderFrames: 16, playbackRate: 1,
+  loopStartFrame: 3,
+  loopEndFrame: 3,
+  renderFrames: 16,
+  playbackRate: 1,
   expected: [0,1,2,3,4,5,6,7,0,1,2,3,4,5,6,7] },
 
 { description: "illegal loop: loopStartFrame < 0",
-  loopStartFrame: -8, loopEndFrame: 3, renderFrames: 16, playbackRate: 1,
+  loopStartFrame: -8,
+  loopEndFrame: 3,
+  renderFrames: 16,
+  playbackRate: 1,
   expected: [0,1,2,3,4,5,6,7,0,1,2,3,4,5,6,7] },
 
 { description: "illegal loop: loopEndFrame > bufferLength",
-  loopStartFrame: 0, loopEndFrame: 30000, renderFrames: 16, playbackRate: 1,
+  loopStartFrame: 0,
+  loopEndFrame: 30000,
+  renderFrames: 16,
+  playbackRate: 1,
   expected: [0,1,2,3,4,5,6,7,0,1,2,3,4,5,6,7] },
 
+// Start a loop with a duration longer than the buffer.  The output should be the data from frame 1
+// to 6, and then looping from 3 to 5 until 30 frames have been played.
+{ description: "loop from 3 -> 6 with offset 1 for 31 frames",
+  loopStartFrame: 3,
+  loopEndFrame: 6,
+  playbackRate: 1,
+  offsetFrame: 1,
+  durationFrames: 30,
+  expected: [1, 2, 3, 4, 5, 3, 4, 5, 3, 4, 5, 3, 4, 5, 3, 4, 5, 3, 4, 5, 3, 4, 5, 3, 4, 5, 3, 4, 5, 3] },
+      
 ];
 
 var sampleRate = 44100;
@@ -111,9 +169,26 @@ function runLoopTest(context, testNumber, test) {
 
     // Render each test one after the other, spaced apart by testSpacingSeconds.
     var startTime = testNumber * testSpacingSeconds;
-    var duration = test.renderFrames / context.sampleRate;
-    source.start(startTime, offset);
-    source.stop(startTime + duration);
+
+    if (test.renderFrames) {    
+        var duration = test.renderFrames / context.sampleRate;
+        if (test.renderFrames > testSpacingFrames || test.renderFrames < 0) {
+            testFailed("Test " + testNumber
+                + ": renderFrames (" + test.renderFrames + ") outside the range [0, "
+                + testSpacingFrames + "]");
+        }
+        source.start(startTime, offset);
+        source.stop(startTime + duration);
+    } else if (test.durationFrames) {
+        if (test.durationFrames > testSpacingFrames || test.durationFrames < 0) {
+            testFailed("Test " + testNumber
+                + ": durationFrames (" + test.durationFrames + ") outside the range [0, "
+                + testSpacingFrames + "]");
+        }
+        source.start(startTime, offset, test.durationFrames / context.sampleRate);
+    } else {
+        testFailed("Test " + testNumber + " must specify one of renderFrames or durationFrames");
+    }
 }
 
 function runTest() {