class TestDirectedGraph

# File test/directed_graph_test.rb, line 9
def setup
  @dg = DirectedAdjacencyGraph.new
  [[1, 2], [2, 3], [3, 2], [2, 4]].each do |(src, target)|
    @dg.add_edge(src, target)
  end
end

# File test/directed_graph_test.rb, line 33
def test_add
  dg = DirectedAdjacencyGraph.new
  dg.add_edge(1, 2)
  assert(!dg.empty?)
  assert(dg.has_edge?(1, 2))
  assert(!dg.has_edge?(2, 1))
  assert(dg.has_vertex?(1) && dg.has_vertex?(2))
  assert(!dg.has_vertex?(3))

  assert_equal([1, 2], dg.vertices.sort)
  assert([DirectedEdge.new(1, 2)].eql?(dg.edges))
  assert_equal("(1-2)", dg.edges.join)

  assert_equal([2], dg.adjacent_vertices(1))
  assert_equal([], dg.adjacent_vertices(2))

  assert_equal(1, dg.out_degree(1))
  assert_equal(0, dg.out_degree(2))
end

# File test/directed_graph_test.rb, line 87
def test_add_vertices
  dg = DirectedAdjacencyGraph.new
  dg.add_vertices 1, 3, 2, 4
  assert_equal dg.vertices.sort, [1, 2, 3, 4]

  dg.remove_vertices 1, 3
  assert_equal dg.vertices.sort, [2, 4]
end

# File test/directed_graph_test.rb, line 96
def test_creating_from_array
  dg = DirectedAdjacencyGraph[1, 2, 3, 4]
  assert_equal([1, 2, 3, 4], dg.vertices.sort)
  assert_equal('(1-2)(3-4)', dg.edges.join)
end

# File test/directed_graph_test.rb, line 53
def test_edges
  assert_equal(4, @dg.edges.length)
  assert_equal([1, 2, 2, 3], @dg.edges.map { |l| l.source }.sort)
  assert_equal([2, 2, 3, 4], @dg.edges.map { |l| l.target }.sort)
  assert_equal("(1-2)(2-3)(2-4)(3-2)", @dg.edges.map { |l| l.to_s }.sort.join)
  #    assert_equal([0,1,2,3], @dg.edges.map {|l| l.info}.sort)
end

# File test/directed_graph_test.rb, line 65
def test_edges_from_to?
  assert @dg.has_edge?(1, 2)
  assert @dg.has_edge?(2, 3)
  assert @dg.has_edge?(3, 2)
  assert @dg.has_edge?(2, 4)
  assert !@dg.has_edge?(2, 1)
  assert !@dg.has_edge?(3, 1)
  assert !@dg.has_edge?(4, 1)
  assert !@dg.has_edge?(4, 2)
end

# File test/directed_graph_test.rb, line 16
def test_empty_graph
  dg = DirectedAdjacencyGraph.new
  assert dg.empty?
  assert dg.directed?
  assert(!dg.has_edge?(2, 1))
  assert(!dg.has_vertex?(3))
  # Non existent vertex result in a Name Error because each_key is
  # called for nil
  assert_raises(NoVertexError) { dg.out_degree(3) }
  assert_equal([], dg.vertices)
  assert_equal(0, dg.size)
  assert_equal(0, dg.num_vertices)
  assert_equal(0, dg.num_edges)
  assert_equal(DirectedEdge, dg.edge_class)
  assert([].eql?(dg.edges))
end

# File test/directed_graph_test.rb, line 76
def test_remove_edges
  @dg.remove_edge 1, 2
  assert !@dg.has_edge?(1, 2)
  @dg.remove_edge 1, 2
  assert !@dg.has_edge?(1, 2)
  @dg.remove_vertex 3
  assert !@dg.has_vertex?(3)
  assert !@dg.has_edge?(2, 3)
  assert_equal('(2-4)', @dg.edges.join)
end

# File test/directed_graph_test.rb, line 102
def test_reverse
  # Add isolated vertex
  @dg.add_vertex(42)
  reverted = @dg.reverse

  @dg.each_edge do |u, v|
    assert(reverted.has_edge?(v, u))
  end

  assert(reverted.has_vertex?(42), 'Reverted graph should contain isolated Vertex 42')
end

# File test/directed_graph_test.rb, line 114
def test_to_undirected
  undirected = @dg.to_undirected
  assert_equal '(1=2)(2=3)(2=4)', undirected.edges.sort.join
end

# File test/directed_graph_test.rb, line 61
def test_vertices
  assert_equal([1, 2, 3, 4], @dg.vertices.sort)
end