Each pointer needs its own stack, merging the two packages to avoid a circular dependency

pkg/pointer/pointer_test.go

@@ -9,7 +9,7 @@ import (
 )
 
 func TestNewPointer(t *testing.T) {
-	require.Equal(t, NewPointer(), &Pointer{dx: 1})
+	require.Equal(t, NewPointer(), &Pointer{dx: 1, ss: NewStackStack()})
 }
 
 func TestSplit(t *testing.T) {
@@ -23,8 +23,8 @@ func TestSplit(t *testing.T) {
 	// We check that p2 is a real copy
 	p.Step(*f)
 	p2.Step(*f)
-	require.Equal(t, &Pointer{x: 1, y: 0, dx: 1}, p)
-	require.Equal(t, &Pointer{x: 1, y: 0, dx: 1}, p2)
+	require.Equal(t, &Pointer{x: 1, y: 0, dx: 1, ss: NewStackStack()}, p)
+	require.Equal(t, &Pointer{x: 1, y: 0, dx: 1, ss: NewStackStack()}, p2)
 }
 
 func TestStep(t *testing.T) { // Step is thoroughly tested in the field package
@@ -50,3 +50,61 @@ func TestGet(t *testing.T) {
 	v := p.Get(*f)
 	require.Equal(t, int('@'), v)
 }
+
+func TestSet(t *testing.T) {
+	p := NewPointer()
+	p.Set(3, 14)
+	require.Equal(t, 3, p.x)
+	require.Equal(t, 14, p.y)
+}
+
+func TestRedirectTo(t *testing.T) {
+	p := NewPointer()
+	p.RedirectTo(3, 14)
+	require.Equal(t, 3, p.dx)
+	require.Equal(t, 14, p.dy)
+}
+
+func TestReverse(t *testing.T) {
+	p := NewPointer()
+	p.RedirectTo(3, 14)
+	p.Reverse()
+	require.Equal(t, -3, p.dx)
+	require.Equal(t, -14, p.dy)
+}
+
+func TestRedirect(t *testing.T) {
+	testCases := []struct {
+		name       string
+		input      byte
+		expectedDx int
+		expectedDy int
+	}{
+		{"up", '^', 0, -1},
+		{"right", '>', 1, 0},
+		{"down", 'v', 0, 1},
+		{"left", '<', -1, 0},
+		{"turn left", '[', 14, -3},
+		{"turn right", ']', -14, 3},
+		{"reverse", 'r', -3, -14},
+		{"redirectTo", 'x', 2, 7},
+	}
+	for _, tc := range testCases {
+		t.Run(tc.name, func(t *testing.T) {
+			p := NewPointer()
+			p.RedirectTo(3, 14)
+			p.ss.Push(2)
+			p.ss.Push(7)
+			v := p.Redirect(int(tc.input))
+			require.Equal(t, true, v)
+			require.Equal(t, tc.expectedDx, p.dx, "Invalid dx value")
+			require.Equal(t, tc.expectedDy, p.dy, "Invalid dy value")
+		})
+	}
+	// We cannot really test random, can we? This just gives coverage
+	p := NewPointer()
+	v := p.Redirect(int('?'))
+	require.Equal(t, true, v)
+	// A character that does not redirect should return false
+	require.Equal(t, false, p.Redirect(int('@')))
+}