Add test

Author: liufengyun

tests/init-global/pos/array-buffer.scala

@@ -0,0 +1,20 @@
+class ArrayBuffer(initialSize: Int):
+  def this() = this(0)
+
+  var size = initialSize
+
+  def ++=(delta: Int): this.type =
+    size = size + delta
+    this
+
+object ArrayBuffer:
+  def from(size: Int): ArrayBuffer =
+    new ArrayBuffer() ++= size
+
+object Test:
+  def enlarge(buffer: ArrayBuffer) = buffer ++= 20
+  enlarge(ArrayBuffer.from(4))
+  enlarge(ArrayBuffer.from(8))
+  enlarge(ArrayBuffer.from(16))
+  enlarge(ArrayBuffer.from(32))
+  enlarge(ArrayBuffer.from(64))