Feature/Parity: Support beep

Author: LaCuneta

compiler/shared/src/main/scala/SimplePrims.scala

@@ -445,6 +445,7 @@ object SimplePrims {
         case _: prim.etc._exportview            => "ImportExportPrims.exportView"
         case _: prim.etc._exportworld           => "ImportExportPrims.exportWorld"
         case _: prim.etc._wait                  => "Prims.wait"
+        case _: prim.etc._beep                  => "Prims.beep"
 
         case _: prim.etc._importdrawing => "ImportExportPrims.importDrawing"
 

compiler/shared/src/test/scala/CompiledModelTest.scala

@@ -47,7 +47,7 @@ class CompiledModelTest extends AnyFunSuite {
   test("model with unimplemented primitives can be compiled") {
     val unimplemented =
       s"""|to go
-          |  beep
+          |  export-interface "file.png"
           |end""".stripMargin
     testModelCode(unimplemented, isInvalid, CompilerFlags(generateUnimplemented = false))
     testModelCode(unimplemented, isValid,   CompilerFlags(generateUnimplemented = true))

engine/src/main/coffee/engine/prim/prims.coffee

@@ -86,6 +86,25 @@ module.exports =
         notImplemented('display', undefined)
       return
 
+    # () => Unit
+    beep: () ->
+      AudioCtx = (typeof AudioContext != 'undefined' and AudioContext) or
+                 (typeof webkitAudioContext != 'undefined' and webkitAudioContext)
+      if AudioCtx
+        ctx = new AudioCtx()
+        oscillator = ctx.createOscillator()
+        gain = ctx.createGain()
+        oscillator.connect(gain)
+        gain.connect(ctx.destination)
+        oscillator.frequency.value = 880
+        gain.gain.setValueAtTime(0.3, ctx.currentTime)
+        gain.gain.exponentialRampToValueAtTime(0.001, ctx.currentTime + 0.2)
+        oscillator.start(ctx.currentTime)
+        oscillator.stop(ctx.currentTime + 0.2)
+      else
+        @_printPrims.print('BEEP')
+      return
+
     # (Any) => Boolean
     ifElseValueBooleanCheck: (b) ->
       @booleanCheck(b, "IFELSE-VALUE")