class TestUnDirectedGraph

# File test/undirected_graph_test.rb, line 10
def setup
  @dg = AdjacencyGraph.new
  [[1, 2], [2, 3], [3, 2], [2, 4]].each do |(src, target)|
    @dg.add_edge(src, target)
  end
end

# File test/undirected_graph_test.rb, line 35
def test_add
  dg = AdjacencyGraph.new
  dg.add_edge(1, 2)
  assert(!dg.empty?)
  assert(dg.has_edge?(1, 2))
  assert(dg.has_edge?(2, 1), "Backwards edge not included!")
  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([1], dg.adjacent_vertices(2))

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

# File test/undirected_graph_test.rb, line 88
def test_add_vertices
  dg = AdjacencyGraph.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]

  dg.remove_vertices 1, 3, Object # ones again
  assert_equal dg.vertices.sort, [2, 4]
end

# File test/undirected_graph_test.rb, line 55
  def test_edges
    assert_equal(3, @dg.edges.length)
    edges = [[1, 2], [2, 3], [2, 4]].map { |x| UnDirectedEdge.new(*x) }
    assert_equal(edges, @dg.edges.sort)
#    assert_equal([0,1,2,3], @dg.edges.map {|l| l.info}.sort)
  end

# File test/undirected_graph_test.rb, line 66
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/undirected_graph_test.rb, line 17
def test_empty_graph
  dg = AdjacencyGraph.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(UnDirectedEdge, dg.edge_class)
  assert([].eql?(dg.edges))
  assert([].eql?(dg.to_a))
end

# File test/undirected_graph_test.rb, line 77
def test_remove_edges
  @dg.remove_edge 1, 2
  assert !@dg.has_edge?(1, 2), "(1,2) should not be an edge any more."
  @dg.remove_edge 1, 2
  assert !@dg.has_edge?(2, 1)
  @dg.remove_vertex 3
  assert !@dg.has_vertex?(3), "3 should not be a vertex any more."
  assert !@dg.has_edge?(2, 3)
  assert_equal([UnDirectedEdge.new(2, 4)], @dg.edges)
end

# File test/undirected_graph_test.rb, line 100
def test_reverse
  assert_equal(@dg, @dg.reverse)
end

# File test/undirected_graph_test.rb, line 62
def test_vertices
  assert_equal([1, 2, 3, 4], @dg.vertices.sort)
end