internal void Graph_OutEdgesShouldHaveSameTail(GraphDefinitionParameter p)
{
// Arrange
using MutableUndirectedSimpleIncidenceGraph builder = new(p.VertexCount);
foreach (Endpoints endpoints in p.Edges)
{
builder.Add(endpoints.Tail, endpoints.Head);
}
Graph graph = builder.ToGraph();
// Act
for (int vertex = 0; vertex < graph.VertexCount; ++vertex)
{
EdgeEnumerator outEdges = graph.EnumerateOutEdges(vertex);
while (outEdges.MoveNext())
{
Endpoints edge = outEdges.Current;
bool hasTail = graph.TryGetTail(edge, out int tail);
if (!hasTail)
{
Assert.True(hasTail);
}
// Assert
Assert.Equal(vertex, tail);
}
}
}
internal void Graph_ShouldContainSameSetOfEdges(GraphDefinitionParameter p)
{
// Arrange
using MutableSimpleIncidenceGraph builder = new(p.VertexCount);
foreach (Endpoints endpoints in p.Edges)
{
builder.Add(endpoints.Tail, endpoints.Head);
}
Graph graph = builder.ToGraph();
HashSet <Endpoints> expectedEdgeSet = p.Edges.ToHashSet();
// Act
HashSet <Endpoints> actualEdgeSet = new();
for (int vertex = 0; vertex < graph.VertexCount; ++vertex)
{
EdgeEnumerator outEdges = graph.EnumerateOutEdges(vertex);
while (outEdges.MoveNext())
{
Endpoints edge = outEdges.Current;
bool hasEndpoints = TryGetEndpoints(graph, edge, out Endpoints endpoints);
if (!hasEndpoints)
{
Assert.True(hasEndpoints);
}
actualEdgeSet.Add(endpoints);
}
}
// Assert
Assert.Equal(expectedEdgeSet, actualEdgeSet, HashSetEqualityComparer);
}
private static bool TryGetEndpoints(Graph graph, Endpoints edge, out Endpoints endpoints)
{
bool hasTail = graph.TryGetTail(edge, out int tail);
bool hasHead = graph.TryGetHead(edge, out int head);
endpoints = new Endpoints(tail, head);
return(hasTail && hasHead);
}
internal void Graph_SizeShouldMatch(GraphDefinitionParameter p)
{
// Arrange
using MutableUndirectedSimpleIncidenceGraph builder = new(p.VertexCount);
foreach (Endpoints endpoints in p.Edges)
{
builder.Add(endpoints.Tail, endpoints.Head);
}
// Act
Graph graph = builder.ToGraph();
// Assert
Assert.Equal(p.VertexCount, graph.VertexCount);
Assert.Equal(p.Edges.Count, graph.EdgeCount);
}
internal void EnumerateEdges(GraphParameter <Graph> p)
{
Graph graph = p.Graph;
// Arrange
int source = graph.VertexCount >> 1;
byte[] setBackingStore = ArrayPool <byte> .Shared.Rent(Math.Max(graph.VertexCount, source + 1));
Array.Clear(setBackingStore, 0, setBackingStore.Length);
IndexedSet exploredSet = new(setBackingStore);
// Act
IEnumerator <Endpoints> basicSteps = Dfs.EnumerateEdges(graph, source, graph.VertexCount) !;
IEnumerator <Endpoints> enumerableSteps = EnumerableDfs.EnumerateEdges(graph, source, exploredSet) !;
// Assert
while (true)
{
bool expectedHasCurrent = enumerableSteps.MoveNext();
bool actualHasCurrent = basicSteps.MoveNext();
Assert.Equal(expectedHasCurrent, actualHasCurrent);
if (!expectedHasCurrent || !actualHasCurrent)
{
break;
}
Endpoints expected = enumerableSteps.Current;
Endpoints actual = basicSteps.Current;
if (expected != actual)
{
Assert.Equal(expected, actual);
break;
}
}
}