Add tests with 100% coverage for Algorithm\Symmetric

Author: clue

tests/SymmetricTest.php

@@ -0,0 +1,61 @@
+<?php
+
+use Fhaculty\Graph\Algorithm\Symmetric as AlgorithmSymmetric;
+use Fhaculty\Graph\Graph;
+
+class SymmetricTest extends TestCase
+{
+    public function testGraphEmpty()
+    {
+        $graph = new Graph();
+
+        $alg = new AlgorithmSymmetric($graph);
+        
+        $this->assertTrue($alg->isSymmetric());
+    }
+
+    public function testGraphIsolated()
+    {
+        $graph = new Graph();
+        $graph->createVertex(1);
+        $graph->createVertex(2);
+
+        $alg = new AlgorithmSymmetric($graph);
+        
+        $this->assertTrue($alg->isSymmetric());
+    }
+
+    public function testGraphSingleArcIsNotSymmetricr()
+    {
+        // 1 -> 2
+        $graph = new Graph();
+        $graph->createVertex(1)->createEdgeTo($graph->createVertex(2));
+
+        $alg = new AlgorithmSymmetric($graph);
+        
+        $this->assertFalse($alg->isSymmetric());
+    }
+    
+    public function testGraphAntiparallelIsSymmetricr()
+    {
+        // 1 -> 2 -> 1
+        $graph = new Graph();
+        $graph->createVertex(1)->createEdgeTo($graph->createVertex(2));
+        $graph->getVertex(2)->createEdgeTo($graph->getVertex(1));
+    
+        $alg = new AlgorithmSymmetric($graph);
+    
+        $this->assertTrue($alg->isSymmetric());
+    }
+    
+    public function testGraphSingleUndirectedIsSymmetricr()
+    {
+        // 1 -- 2
+        $graph = new Graph();
+        $graph->createVertex(1)->createEdge($graph->createVertex(2));
+    
+        $alg = new AlgorithmSymmetric($graph);
+    
+        $this->assertTrue($alg->isSymmetric());
+    }
+}