fix: add testing cases for copy() and append()

contracts/assign_unnamed_type/append_named_unnamed_type_filetest.gno

@@ -0,0 +1,38 @@
+package main
+
+
+
+type nat []int
+
+func main() {
+
+	var nlist = nat{0}
+	var ulist = []int{1}
+	var n int = 3
+
+	a := append(nlist, n)
+	b := append(ulist, n)
+
+  println(a)
+  println(b)
+
+	a = append(ulist, n)
+	b = append(nlist, n)
+
+	c := append(nlist, ulist...)
+	d := append(ulist, nlist...)
+
+  println(a)
+  println(b)
+  println(c)
+  println(d)
+
+}
+
+// Output:
+// (slice[(0 int),(3 int)] main.nat)
+// slice[(1 int),(3 int)]
+// (slice[(1 int),(3 int)] main.nat)
+// slice[(0 int),(3 int)]
+// (slice[(0 int),(1 int)] main.nat)
+// slice[(1 int),(0 int)]

contracts/assign_unnamed_type/copy_name_unnamed2_type_filetest.gno

@@ -0,0 +1,21 @@
+package main
+
+
+type nat []int
+type nat2 []int
+
+func main() {
+
+	var nlist = nat{0}
+	var n2list = nat2{1}
+
+	copy(nlist, n2list)
+
+
+	println(nlist)
+
+
+}
+
+// Output:
+// (slice[(1 int)] main.nat)

contracts/assign_unnamed_type/copy_name_unnamed_type_filetest.gno

@@ -0,0 +1,27 @@
+package main
+
+type nat []int
+
+func main() {
+
+	var nlist = nat{0}
+	var ulist = []int{1}
+
+	copy(nlist, ulist)
+
+	println(nlist)
+	println(ulist)
+
+	nlist = nat{0}
+	ulist = []int{1}
+	copy(ulist, nlist)
+	println(nlist)
+	println(ulist)
+
+}
+
+// Output:
+// (slice[(1 int)] main.nat)
+// slice[(1 int)]
+// (slice[(0 int)] main.nat)
+// slice[(0 int)]