Imports System Imports System.Linq Imports System.Collections.Generic Imports Xunit Public Class SimpleLinkedListTests Public Sub Empty_list_has_no_elements() Dim list = New SimpleLinkedList(Of Integer)() Assert.Equal(0, list.Count) End Sub Public Sub Count_cannot_be_changed_from_the_outside() Dim count = GetType(SimpleLinkedList(Of)).GetProperty("Count") Assert.True(count?.GetGetMethod().IsPublic) Assert.False(count?.GetSetMethod(True).IsPublic) End Sub Public Sub Pushing_elements_to_the_list_increases_the_count() Dim list = New SimpleLinkedList(Of Integer)() list.Push(0) Assert.Equal(1, list.Count) list.Push(0) Assert.Equal(2, list.Count) End Sub Public Sub Popping_elements_from_the_list_decreases_the_count() Dim list = New SimpleLinkedList(Of Integer)() list.Push(0) list.Push(0) Assert.Equal(2, list.Count) list.Pop() Assert.Equal(1, list.Count) End Sub Public Sub Elements_pop_back_in_lifo_order() Dim list = New SimpleLinkedList(Of Integer)() list.Push(3) list.Push(5) Assert.Equal(5, list.Pop()) list.Push(7) Assert.Equal(7, list.Pop()) Assert.Equal(3, list.Pop()) End Sub Private Shared Function CreateSimpleLinkedList(ByVal value As Integer) As SimpleLinkedList(Of Integer) Dim type = GetType(SimpleLinkedList(Of)).MakeGenericType(GetType(Integer)) Dim constructor = type.GetConstructor(New Type() {GetType(Integer)}) Return If(CType(constructor?.Invoke(New Object() {value}), SimpleLinkedList(Of Integer)), CreateSimpleLinkedList(New Integer() {value})) End Function Private Shared Function CreateSimpleLinkedList(ParamArray values As Integer()) As SimpleLinkedList(Of Integer) Dim type = GetType(SimpleLinkedList(Of)).MakeGenericType(GetType(Integer)) Dim constructor = type.GetConstructor(New Type() {GetType(Integer())}) Return CType(constructor.Invoke(New Object() {values}), SimpleLinkedList(Of Integer)) End Function Public Sub Single_value_initialisation() Dim list = CreateSimpleLinkedList(7) Assert.Equal(1, list.Count) Assert.Equal(7, list.Pop()) End Sub Public Sub Multi_value_initialisation() Dim list = CreateSimpleLinkedList(2, 1, 3) Assert.Equal(3, list.Pop()) Assert.Equal(1, list.Pop()) Assert.Equal(2, list.Pop()) End Sub Public Sub From_enumerable() Dim list = CreateSimpleLinkedList({11, 7, 5, 3, 2}) Assert.Equal(2, list.Pop()) Assert.Equal(3, list.Pop()) Assert.Equal(5, list.Pop()) Assert.Equal(7, list.Pop()) Assert.Equal(11, list.Pop()) End Sub Public Sub Reverse_enumerable() Dim values = Linq.Enumerable.Range(1, 5).ToArray() Dim list = CreateSimpleLinkedList(values) Dim enumerable = Assert.IsAssignableFrom(Of IEnumerable(Of Integer))(list) Dim reversed = enumerable.Reverse() Assert.Equal(values, reversed) End Sub Public Sub Roundtrip() Dim values = Linq.Enumerable.Range(1, 7) Dim list = CreateSimpleLinkedList(values.ToArray()) Dim enumerable = Assert.IsAssignableFrom(Of IEnumerable(Of Integer))(list) Assert.Equal(values.Reverse(), enumerable) End Sub End Class