Added test harness hooks

Author: cwoffenden

test/test_interactive.py

@@ -306,7 +306,7 @@ def test_audio_worklet_tone_generator(self):
   def test_audio_worklet_modularize(self):
     self.btest('webaudio/audioworklet.c', expected='0', args=['-sAUDIO_WORKLET', '-sWASM_WORKERS', '-sMINIMAL_RUNTIME', '-sMODULARIZE'])
 
-  # Tests an AudioWorklet with multiple stereo inputs mixing to a single output
+  # Tests an AudioWorklet with multiple stereo inputs mixing in the processor to a single stereo output
   def test_audio_worklet_stereo_io(self):
     os.mkdir('audio_files')
     shutil.copy(test_file('webaudio/audio_files/emscripten-beat.mp3'), 'audio_files/')

test/webaudio/audioworklet_in_out_stereo.c

@@ -5,11 +5,19 @@
 #include <emscripten/em_js.h>
 #include <emscripten/webaudio.h>
 
+// This needs to be big enough for the stereo output, 2x inputs and the worker stack
 #define AUDIO_STACK_SIZE 4096
 
+// REPORT_RESULT is defined when running in Emscripten test harness.
 #ifdef REPORT_RESULT
-void playedAndMixed(void* data) {
-	REPORT_RESULT(0);
+// Count the mixed frames and return after 375 frames (1 second with the default 128 size)
+volatile int audioProcessedCount = 0;
+bool playedAndMixed(double time, void* data) {
+	if (audioProcessedCount >= 375) {
+		REPORT_RESULT(0);
+		return false;
+	}
+	return true;
 }
 #endif
 
@@ -49,6 +57,9 @@ EM_JS(void, toggleTrack, (EMSCRIPTEN_WEBAUDIO_T srcID), {
 
 // Callback to process and mix the audio tracks
 bool process(int numInputs, const AudioSampleFrame* inputs, int numOutputs, AudioSampleFrame* outputs, int numParams, const AudioParamFrame* params, void* data) {
+#ifdef REPORT_RESULT
+	audioProcessedCount++;
+#endif
 	// Single stereo output
 	assert(numOutputs == 1 && outputs[0].numberOfChannels == 2);
 	for (int n = 0; n < numInputs; n++) {
@@ -116,6 +127,10 @@ void processorCreated(EMSCRIPTEN_WEBAUDIO_T context, bool success, void* data) {
 		}
 
 		emscripten_set_click_callback(EMSCRIPTEN_EVENT_TARGET_DOCUMENT, (void*) (context), false, &onClick);
+		
+#ifdef REPORT_RESULT
+		emscripten_set_timeout_loop(&playedAndMixed, 16, NULL);
+#endif
 	} else {
 		printf("Audio worklet node creation failed\n");
 	}