Add scratch tests

Author: Aidan Lee

test/native/Native.hx

@@ -18,6 +18,8 @@ class Native
 			new tests.TestNativeEnum(),
 
 			#if (haxe_ver>=5)
+            new tests.TestScratch(),
+
             new tests.marshalling.classes.TestLocalValueType(),
             new tests.marshalling.classes.TestClassValueType(),
             new tests.marshalling.classes.TestInterfaceValueType(),

test/native/tests/TestScratch.hx

@@ -0,0 +1,53 @@
+package tests;
+
+import cpp.Scratch;
+import utest.Test;
+import utest.Assert;
+
+using haxe.Int64;
+
+class TestScratch extends Test {
+	function test_zeroed_small_alloc() {
+		final size  = 16;
+		final alloc = Scratch.alloc(size);
+
+		Assert.equals(size, alloc.view.length.toInt());
+
+		for (i in 0...size.toInt()) {
+			Assert.equals(0, alloc.view[i]);
+		}
+	}
+
+	function test_zeroed_large_alloc() {
+		final size  = 100_000;
+		final alloc = Scratch.alloc(size);
+
+		Assert.equals(size, alloc.view.length.toInt());
+
+		for (i in 0...size.toInt()) {
+			Assert.equals(0, alloc.view[i]);
+		}
+	}
+
+	function test_contents_wiped() {
+		{
+			final size  = 16;
+			final alloc = Scratch.alloc(size);
+
+			Assert.equals(size, alloc.view.length.toInt());
+
+			alloc.view.fill(7);
+		}
+
+		{
+			final size  = 16;
+			final alloc = Scratch.alloc(size);
+
+			Assert.equals(size, alloc.view.length.toInt());
+
+			for (i in 0...size.toInt()) {
+				Assert.equals(0, alloc.view[i]);
+			}
+		}
+	}
+}