spec/graph/graph_spec.rb

   1 require File.expand_path(File.dirname(__FILE__) + '/../spec_helper')
   2
   3 module GraphNjae
   4
   5   class SVertex < Vertex
   6   end
   7
   8   class SEdge < Edge
   9   end
  10
  11   describe Graph do
  12     let (:g) { Graph.new }
  13     describe "#initialize" do
  14       it "creates an empty graph" do
  15         g = Graph.new
  16         g.edges.should be_empty
  17         g.vertices.should be_empty
  18       end
  19
  20       it "creates a graph with some parameters" do
  21         g = Graph.new :value1 => 1, :value2 => "value2", :value3 => :v3
  22         g.value1.should == 1
  23         g.value2.should == "value2"
  24         g.value3.should == :v3
  25         g.value4.should be_nil
  26       end
  27
  28     end # #initialize
  29
  30     describe "adds attribues" do
  31       it "adds then reports arbitrary attributes" do
  32         g.score = 15
  33         g.score == 15
  34       end
  35     end # adds attributes
  36
  37     describe "#<<" do
  38       it "adds a set of vertices" do
  39         g.vertices.should be_empty
  40         v1 = Vertex.new
  41         v2 = Vertex.new
  42         g << v1 << v2
  43         g.should have(2).vertices
  44         g.vertices.should include(v1)
  45         g.vertices.should include(v2)
  46       end
  47
  48       it "adds a set of edges" do
  49         g.edges.should be_empty
  50         e1 = Edge.new
  51         e2 = Edge.new
  52         g << e1 << e2
  53         g.should have(2).edges
  54         g.edges.should include(e1)
  55         g.edges.should include(e2)
  56       end
  57
  58       it "adds a mixed set of vertices and edges" do
  59         g.vertices.should be_empty
  60         g.edges.should be_empty
  61         v1 = Vertex.new
  62         v2 = Vertex.new
  63         e1 = Edge.new
  64         e2 = Edge.new
  65         g << v1 << e1 << v2 << e2
  66         g.should have(2).vertices
  67         g.vertices.should include(v1)
  68         g.vertices.should include(v2)
  69         g.should have(2).edges
  70         g.edges.should include(e1)
  71         g.edges.should include(e2)
  72       end
  73
  74       it "adds a subclass of Vertex" do
  75         g.vertices.should be_empty
  76         v1 = SVertex.new
  77         v2 = SVertex.new
  78         g << v1 << v2
  79         g.should have(2).vertices
  80         g.vertices.should include(v1)
  81         g.vertices.should include(v2)
  82       end
  83     end # #<<
  84
  85     describe "connect" do
  86       it "adds and records an edge between vertices" do
  87         g.vertices.should be_empty
  88         g.edges.should be_empty
  89         v1 = Vertex.new(:name => :v1)
  90         v2 = Vertex.new(:name => :v2)
  91         g.connect(v1, v2)
  92
  93         g.should have(2).vertices
  94         g.vertices.should include(v1)
  95         g.vertices.should include(v2)
  96         g.should have(1).edges
  97       end
  98     end # #connect
  99
 100     describe "product" do
 101       it "finds a product graph of a pair of one-vertex graphs" do
 102         g1 = Graph.new
 103         g2 = Graph.new
 104         g1v1 = Vertex.new
 105         g1 << g1v1
 106         g2v1 = Vertex.new
 107         g2 << g2v1
 108         product = g1.product g2
 109
 110         product.should have(1).vertices
 111         product.vertices.first.g1_vertex.should == g1v1
 112         product.vertices.first.g2_vertex.should == g2v1
 113         product.edges.should be_empty
 114       end
 115
 116       it "finds a product graph of a pair of simple graphs" do
 117         g1 = Graph.new
 118         g2 = Graph.new
 119         g1v1 = Vertex.new(:name => :g1v1)
 120         g1v2 = Vertex.new(:name => :g1v2)
 121         g1.connect(g1v1, g1v2)
 122         g2v1 = Vertex.new(:name => :g2v1)
 123         g2v2 = Vertex.new(:name => :g2v2)
 124         g2.connect(g2v1, g2v2)
 125         pg = g1.product g2
 126
 127         pg.should have(4).vertices
 128         pg.should have(2).edges
 129       end
 130
 131     end
 132
 133   end
 134 end