Reset the API stack after a foreign constructor returns.

test/api/reset_stack_after_foreign_construct.c

@@ -0,0 +1,44 @@
+#include <stdio.h>
+#include <string.h>
+
+#include "foreign_class.h"
+
+static void counterAllocate(WrenVM* vm)
+{
+  double* counter = (double*)wrenSetSlotNewForeign(vm, 0, 0, sizeof(double));
+  *counter = wrenGetSlotDouble(vm, 1);
+}
+
+void resetStackAfterForeignConstructBindClass(
+    const char* className, WrenForeignClassMethods* methods)
+{
+  if (strcmp(className, "ResetStackForeign") == 0)
+  {
+    methods->allocate = counterAllocate;
+    return;
+  }
+}
+
+void resetStackAfterForeignConstructRunTests(WrenVM* vm)
+{
+  wrenEnsureSlots(vm, 1);
+  wrenGetVariable(vm, "main", "Test", 0);
+  WrenHandle* testClass = wrenGetSlotHandle(vm, 0);
+  
+  WrenHandle* callConstruct = wrenMakeCallHandle(vm, "callConstruct()");
+  WrenHandle* afterConstruct = wrenMakeCallHandle(vm, "afterConstruct(_,_)");
+  
+  wrenEnsureSlots(vm, 1);
+  wrenSetSlotHandle(vm, 0, testClass);
+  wrenCall(vm, callConstruct);
+
+  wrenEnsureSlots(vm, 3);
+  wrenSetSlotHandle(vm, 0, testClass);
+  wrenSetSlotDouble(vm, 1, 1.0);
+  wrenSetSlotDouble(vm, 2, 2.0);
+  wrenCall(vm, afterConstruct);
+  
+  wrenReleaseHandle(vm, testClass);
+  wrenReleaseHandle(vm, callConstruct);
+  wrenReleaseHandle(vm, afterConstruct);
+}