monora/rgl

require 'test_helper'

require 'rgl/implicit'
require 'rgl/adjacency'

include RGL

class TestImplicit < Test::Unit::TestCase
  def setup
    @dg = DirectedAdjacencyGraph.new
    [[1, 2], [2, 3], [2, 4], [4, 5], [1, 6], [6, 4]].each do |(src, target)|
      @dg.add_edge(src, target)
    end

    @cycle = ImplicitGraph.new { |g|
      g.vertex_iterator { |b| 0.upto(4, &b) }
      g.adjacent_iterator { |x, b| b.call((x+1)%5) }
      g.directed = true
    }
  end

  def test_empty
    empty = ImplicitGraph.new
    assert(empty.empty?)
    assert_equal([], empty.edges)
    assert_equal([], empty.vertices)
  end

  def test_cycle
    assert(!@cycle.empty?)
    assert_equal([0, 1, 2, 3, 4], @cycle.vertices.sort)
    assert_equal("(0-1)(1-2)(2-3)(3-4)(4-0)", @cycle.edges.sort.join)
  end

  def test_vertex_filtered_graph
    fg = @cycle.vertices_filtered_by { |v| v%2 == 0 }
    assert_equal([0, 2, 4], fg.vertices.sort)
    assert_equal("(4-0)", fg.edges.sort.join)
    assert(fg.directed?)

    fg = @dg.vertices_filtered_by { |v| v%2 == 0 }
    assert_equal([2, 4, 6], fg.vertices.sort)
    assert_equal("(2-4)(6-4)", fg.edges.sort.join)
    assert(fg.directed?)
  end

  def test_edge_filtered_graph
    fg = @cycle.edges_filtered_by { |u, v| u+v > 3 }
    assert_equal(@cycle.vertices.sort, fg.vertices.sort)
    assert_equal("(2-3)(3-4)(4-0)", fg.edges.sort.join)
    assert(fg.directed?)
  end
end