public void Should_Return_Empty_If_Not_Found()
{
var graph = new CakeGraph();
graph.Connect("A", "B");
graph.Connect("B", "C");
var result = graph.Traverse("E").ToArray();
Assert.Equal(0, result.Length);
}
public void Should_Not_Create_Edge_Between_Connected_Nodes_If_An_Edge_Already_Exist_Regardless_Of_Casing()
{
// Given
var graph = new CakeGraph();
graph.Connect("start", "end");
// When
graph.Connect("START", "END");
// Then
Assert.Equal(1, graph.Edges.Count);
}
public void Should_Throw_If_Encountering_Circular_Reference()
{
var graph = new CakeGraph();
graph.Connect("A", "B");
graph.Connect("B", "C");
graph.Connect("C", "A");
var result = Record.Exception(() => graph.Traverse("C"));
Assert.IsType <CakeException>(result);
Assert.Equal("Graph contains circular references.", result.Message);
}
public void Should_Not_Group_NonParallel_Nodes()
{
var graph = new CakeGraph();
graph.Connect("A", "B");
graph.Connect("B", "C");
var result = graph.Traverse("C").ToArray();
Assert.Equal(3, result.Length);
Assert.Equal("A", result[0]);
Assert.Equal("B", result[1]);
Assert.Equal("C", result[2]);
}
public void Should_Throw_If_Edge_Is_Unidirectional_Regardless_Of_Casing()
{
// Given
var graph = new CakeGraph();
graph.Connect("start", "end");
// When
var result = Record.Exception(() => graph.Connect("END", "START"));
// Then
Assert.IsType <CakeException>(result);
Assert.Equal("Unidirectional edges in graph are not allowed.", result.Message);
}
public void Should_Throw_If_Edge_Is_Unidirectional()
{
// Given
var graph = new CakeGraph();
graph.Connect("start", "end");
// When
var exception = Record.Exception(() => graph.Connect("end", "start"));
// Then
Assert.IsType <CakeException>(exception);
Assert.Equal("Unidirectional edges in graph are not allowed.", exception.Message);
}
public void Should_Throw_If_Edge_Is_Unidirectional_Regardless_Of_Casing()
{
// Given
var graph = new CakeGraph();
graph.Connect("start", "end");
// When
var result = Record.Exception(() => graph.Connect("END", "START"));
// Then
Assert.IsType <CakeException>(result);
Assert.Equal($"Unidirectional edges in graph are not allowed.{Environment.NewLine}\"start\" and \"end\" cannot depend on each other.", result?.Message);
}
public void Should_Return_Empty_Collection_Of_Nodes_If_Target_Was_Not_Found()
{
// Given
var graph = new CakeGraph();
graph.Connect("A", "B");
graph.Connect("C", "D");
graph.Connect("B", "C");
// When
var result = graph.Traverse("E").ToArray();
// Then
Assert.Equal(0, result.Length);
}
public void Should_Traverse_Graph_In_Correct_Order_Regardless_Of_Casing_Of_Root()
{
// Given
var graph = new CakeGraph();
graph.Connect("A", "B");
graph.Connect("C", "D");
graph.Connect("B", "C");
// When
var result = graph.Traverse("d").ToArray();
// Then
Assert.Equal(4, result.Length);
Assert.Equal("A", result[0]);
Assert.Equal("B", result[1]);
Assert.Equal("C", result[2]);
Assert.Equal("d", result[3]);
}
public void Should_Skip_Nodes_That_Are_Not_On_The_Way_To_The_Target()
{
// Given
var graph = new CakeGraph();
graph.Connect("A", "B");
graph.Connect("B", "C");
graph.Connect("B", "D");
graph.Connect("D", "E");
// When
var result = graph.Traverse("E").ToArray();
// Then
Assert.Equal(4, result.Length);
Assert.Equal("A", result[0]);
Assert.Equal("B", result[1]);
Assert.Equal("D", result[2]);
Assert.Equal("E", result[3]);
}
public void Should_Create_Edge_Between_Connected_Nodes()
{
// Given
var graph = new CakeGraph();
// When
graph.Connect("start", "end");
// Then
Assert.Equal("start", graph.Edges[0].Start);
Assert.Equal("end", graph.Edges[0].End);
}
public void Should_Throw_If_Edge_Is_Reflexive()
{
// Given
var graph = new CakeGraph();
// When
var result = Record.Exception(() => graph.Connect("start", "start"));
// Then
Assert.IsType <CakeException>(result);
Assert.Equal("Reflexive edges in graph are not allowed.", result.Message);
}
public void Should_Group_Parallel_Nodes()
{
var graph = new CakeGraph();
graph.Connect("1", "2");
graph.Connect("1", "3");
graph.Connect("1", "4");
graph.Connect("2", "5");
graph.Connect("3", "5");
graph.Connect("4", "5");
var result = graph.TraverseAndGroup("5").ToArray();
Assert.Equal(3, result.Length);
Assert.Equal(1, result[0].Count());
Assert.Equal("1", result[0].First());
Assert.Equal(3, result[1].Count());
Assert.Equal("2", result[1].First());
Assert.Equal("3", result[1].Skip(1).First());
Assert.Equal("4", result[1].Skip(2).First());
Assert.Equal(1, result[2].Count());
Assert.Equal("5", result[2].First());
}
public void Should_Add_End_Node_If_Missing_To_Node_Collection()
{
// Given
var graph = new CakeGraph();
graph.Add("start");
// When
graph.Connect("start", "end");
// Then
Assert.Equal(2, graph.Nodes.Count);
}
