Swap Vertex ctor $graph and $id attributes

A Vertex can not exist without a Graph instance

Author: clue

lib/Fhaculty/Graph/Graph.php

@@ -82,7 +82,7 @@ public function createVertex($id = NULL, $returnDuplicate = false)
             return $this->vertices->getVertexId($id);
         }
 
-        return new Vertex($id, $this);
+        return new Vertex($this, $id);
     }
 
     /**
@@ -98,7 +98,7 @@ public function createVertexClone(Vertex $originalVertex)
         if ($this->vertices->hasVertexId($id)) {
             throw new RuntimeException('Id of cloned vertex already exists');
         }
-        $newVertex = new Vertex($id, $this);
+        $newVertex = new Vertex($this, $id);
         // TODO: properly set attributes of vertex
         $newVertex->setLayout($originalVertex->getLayout());
         $newVertex->setBalance($originalVertex->getBalance());
@@ -256,7 +256,7 @@ public function createVertices($n)
         $vertices = array();
         if (is_int($n) && $n >= 0) {
             for ($id = $this->getNextId(), $n += $id; $id < $n; ++$id) {
-                $vertices[$id] = new Vertex($id, $this);
+                $vertices[$id] = new Vertex($this, $id);
             }
         } elseif (is_array($n)) {
             // array given => check to make sure all given IDs are available (atomic operation)
@@ -275,7 +275,7 @@ public function createVertices($n)
 
             // actually create all requested vertices
             foreach ($n as $id) {
-                $vertices[$id] = new Vertex($id, $this);
+                $vertices[$id] = new Vertex($this, $id);
             }
         } else {
             throw new InvalidArgumentException('Invalid number of vertices given. Must be non-negative integer or an array of Vertex IDs');

lib/Fhaculty/Graph/Vertex.php

@@ -45,11 +45,11 @@ class Vertex extends Layoutable implements EdgesAggregate
     /**
      * Create a new Vertex
      *
-     * @param string|int $id    identifier used to uniquely identify this vertex in the graph
      * @param Graph      $graph graph to be added to
+     * @param string|int $id    identifier used to uniquely identify this vertex in the graph
      * @see Graph::createVertex() to create new vertices
      */
-    public function __construct($id, Graph $graph)
+    public function __construct(Graph $graph, $id)
     {
         if (!is_int($id) && !is_string($id)) {
             throw new InvalidArgumentException('Vertex ID has to be of type integer or string');

tests/Fhaculty/Graph/VertexTest.php

@@ -21,7 +21,7 @@ public function testPrecondition()
 
     public function testConstructor()
     {
-        $v2 = new Vertex(2, $this->graph);
+        $v2 = new Vertex($this->graph, 2);
 
         $this->assertCount(2, $this->graph->getVertices());
         $this->assertTrue($this->graph->hasVertex(2));
@@ -34,7 +34,7 @@ public function testConstructor()
      */
     public function testCanNotConstructDuplicateVertex()
     {
-        $v2 = new Vertex(1, $this->graph);
+        $v2 = new Vertex($this->graph, 1);
     }
 
     public function testEdges()