Implemented the stackstack

tests/stack.nim

@@ -130,6 +130,13 @@ suite "Stack":
     check full.data[0] == 1
     check empty.data[0] == 2
     check empty.data[1] == 3
+  test "Discard":
+    var empty = NewStack()
+    empty[].Discard(1)
+    check empty.height == 0
+    empty[].Push(2)
+    empty[].Discard(3)
+    check empty.height == 0
   test "Next":
     var empty = NewStack()
     check empty[].Next() == nil

tests/stackStack.nim

@@ -0,0 +1,104 @@
+import unittest
+
+include ../src/stackStack
+
+suite "StackStack":
+  test "Pop":
+    var empty = NewStackStack()
+    check empty[].Pop() == 0
+  test "Push":
+    var empty = NewStackStack()
+    empty[].Push(5)
+    check empty[].Pop() == 5
+  test "PopVector":
+    var empty = NewStackStack()
+    check empty[].PopVector() == (0, 0)
+  test "PushVector":
+    var empty = NewStackStack()
+    empty[].PushVector((3, 2))
+    check empty[].PopVector() == (3, 2)
+  test "Clear":
+    var empty = NewStackStack()
+    empty[].Push(3)
+    empty[].Clear()
+    check empty[].Pop() == 0
+  test "Begin":
+    var empty = NewStackStack()
+    empty[].Begin((1, 2))
+    check empty.height == 2
+    check empty[].Pop() == 0
+    empty[].Push(5)
+    empty[].Push(6)
+    empty[].Push(4)
+    empty[].Begin((3, 4))
+    check empty.height == 3
+    check empty[].Pop() == 6
+    check empty[].Pop() == 5
+    check empty[].Pop() == 0
+    check empty[].Pop() == 0
+    empty[].Push(7)
+    empty[].Push(8)
+    empty[].Push(9)
+    empty[].Push(2)
+    empty[].Begin((10, 11))
+    check empty.height == 4
+    check empty[].Pop() == 9
+    check empty[].Pop() == 8
+    check empty[].Pop() == 0
+    empty[].Push(13)
+    empty[].Push(14)
+    empty[].Push(-2)
+    empty[].Begin((15, 16))
+    check empty[].Pop() == 0
+  test "End":
+    var empty = NewStackStack()
+    var v: tuple[x,y: int] = (0, 0)
+    empty[].Push(1)
+    check empty[].End(v) == true
+    check empty.height == 1
+    check empty[].Pop() == 1
+    empty[].Push(1)
+    empty[].Push(2)
+    empty[].Push(3)
+    empty[].Push(4)
+    empty[].Push(2)
+    v = (5, 6)
+    empty[].Begin(v)
+    v = (0, 0)
+    empty[].Push(2)
+    check empty[].End(v) == false
+    check v == (5, 6)
+    check empty.height == 1
+    check empty[].End(v) == true
+    check empty[].Pop() == 4
+    check empty[].Pop() == 3
+    check empty[].Pop() == 2
+    check empty[].Pop() == 1
+    empty[].Push(1)
+    empty[].Push(2)
+    empty[].Push(3)
+    empty[].Push(4)
+    empty[].Push(2)
+    empty[].Begin(v)
+    empty[].Push(4)
+    check empty[].End(v) == false
+    check v == (5, 6)
+    check empty.height == 1
+    check empty[].Pop() == 4
+    check empty[].Pop() == 3
+    check empty[].Pop() == 0
+    check empty[].Pop() == 0
+    check empty[].Pop() == 2
+    check empty[].Pop() == 1
+    empty[].Push(1)
+    empty[].Push(2)
+    empty[].Push(3)
+    empty[].Push(4)
+    empty[].Push(1)
+    empty[].Begin(v)
+    empty[].Push(-2)
+    check empty[].End(v) == false
+    check v == (5, 6)
+    check empty.height == 1
+    check empty[].Pop() == 1
+    check empty[].Pop() == 0