Graph algorithm is now a configuration setting

Author: edno

README.md

@@ -23,14 +23,19 @@ The extension can be installed using [Composer](https://getcomposer.org)
 $ composer require edno/codeception-graphwalker
 ```
 
-And add the **GraphWalker** format to the list of supported format into your suite configuration file (`.suite.yml`):
+## Configuration
+Add the **GraphWalker** format to the list of supported format into your suite configuration file (`.suite.yml`):
 ```yaml
 formats:
   - \edno\codeception-graphwalker\GraphWalker
 ```
 
-## Usage
-> To be documented
+In the configuration file, declare the graph algorithm class to be used:
+```yaml
+graphwalker:
+    algorithm: Graphp\Algorithms\ShortestPath\Dijkstra
+```
+*Refer to [graphp/algorithms](https://github.com/graphp/algorithms) for supported algorithms.*
 
 ## License
 [![FOSSA Status](https://app.fossa.io/api/projects/git%2Bgithub.com%2Fedno%2Fcodeception-graphwalker.svg?type=large)](https://app.fossa.io/projects/git%2Bgithub.com%2Fedno%2Fcodeception-graphwalker?ref=badge_large)

src/GraphWalker.php

@@ -2,40 +2,61 @@
 namespace edno\Codeception;
 
 use edno\GraphYEd\Loader as GraphLoader;
-use Graphp\Algorithms\ShortestPath\Dijkstra;
 use Codeception\Test\Loader\LoaderInterface;
 use Codeception\Test\Loader as TestLoader;
+use Codeception\Lib\Di;
+use Codeception\Exception\ModuleConfigException;
+use Codeception\Exception\TestParseException;
+use Codeception\Configuration;
 
 class GraphWalker implements LoaderInterface
 {
+
+  protected static $defaultSettings = [
+      'graphwalker' => [
+          'algorithm' => ''
+      ],
+      'path' => ''
+  ];
+
+  protected $settings = [];
+
   protected $graph;
 
   protected $parser;
 
   protected $tests = [];
 
-  protected $settings = [];
-
   protected $path;
 
+  protected $di;
+
+  protected $algorithmClass;
+
   public function __construct($settings = [])
   {
-      if(isset($settings['path'])) {
-        $this->path = $settings['path'];
-      } else {
-        $this->path = 'tests/';
+      $this->settings = Configuration::mergeConfigs(self::$defaultSettings, $settings);
+      $this->algorithmClass = $this->settings['graphwalker']['algorithm'];
+      if($this->algorithmClass == '' ) {
+        throw new ModuleConfigException(__CLASS__, 'Configuration setting "algorithm" is missing');
       }
-      $this->settings = $settings;
-      
+
+      $this->di = new Di();
+
       $this->parser = new GraphLoader();
       $this->loader = new TestLoader($this->settings);
   }
 
   public function loadTests($filename)
   {
-      $this->graph = $this->parser->loadContents(file_get_contents($filename));
-      $shortestPath = new Dijkstra($this->graph->getVertices()->getVertexFirst());
-      $path = $shortestPath->getWalkTo($this->graph->getVertices()->getVertexLast())->getGraph();
+      try {
+        $this->graph = $this->parser->loadContents(file_get_contents($filename));
+        $start = $this->graph->getVertices()->getVertexFirst();
+        $algorithm = $this->di->instantiate($this->algorithmClass, [$start]);
+      } catch (\Exception $e) {
+        throw new TestParseException(__CLASS__, $e->getMessage());
+      }
+      $path = $algorithm->getWalkTo($this->graph->getVertices()->getVertexLast())->getGraph();
       $steps = $path->getVertices();
       foreach($steps as $step) {
           $file = $this->path . $step->getAttribute('labels')[0];

tests/_data/notagrapfile,graphml

@@ -0,0 +1 @@
+This is for testing purpose only

tests/unit/BasicGraphTest.php

@@ -13,7 +13,12 @@ protected function _before()
     public function testGetTestsFromModel()
     {
         $model = codecept_data_dir().'basicgraph.graphml';
-        $graphwalker = new  GraphWalker(['path' => 'tests/_data/']);
+        $graphwalker = new  GraphWalker([
+                              'path' => 'tests/_data/',
+                              'graphwalker' => [
+                                'algorithm' => 'Graphp\Algorithms\ShortestPath\Dijkstra'
+                              ]
+                            ]);
         $graphwalker->loadTests($model);
         $this->assertInstanceOf('\Fhaculty\Graph\Graph',$graphwalker->getGraph());
         $tests = $graphwalker->getTests();
@@ -26,4 +31,63 @@ public function testGetTestsFromModel()
     }
 
 
+    /**
+      * @expectedException Codeception\Exception\ModuleConfigException
+      */
+    public function testExceptionAlgorithmSettingMissing()
+    {
+        $graphwalker = new  GraphWalker();
+    }
+
+    /**
+      * @expectedException Codeception\Exception\TestParseException
+      */
+    public function testExceptionAlgorithmSettingInvalid()
+    {
+        $model = codecept_data_dir().'basicgraph.graphml';
+        $graphwalker = new  GraphWalker([
+                              'path' => 'tests/_data/',
+                              'graphwalker' => [
+                                'algorithm' => 'Graphp\Algorithms\DoesNotExist'
+                              ]
+                            ]);
+        $graphwalker->loadTests($model);
+        $this->assertInstanceOf('\Fhaculty\Graph\Graph',$graphwalker->getGraph());
+        $tests = $graphwalker->getTests();
+    }
+
+    /**
+      * @expectedException Codeception\Exception\TestParseException
+      */
+    public function testExceptionTestFileNotExist()
+    {
+      $model = codecept_data_dir().'doesnotexist.graphml';
+      $graphwalker = new  GraphWalker([
+                            'path' => 'tests/_data/',
+                            'graphwalker' => [
+                              'algorithm' => 'Graphp\Algorithms\ShortestPath\Dijkstra'
+                            ]
+                          ]);
+      $graphwalker->loadTests($model);
+      $this->assertInstanceOf('\Fhaculty\Graph\Graph',$graphwalker->getGraph());
+      $tests = $graphwalker->getTests();
+    }
+
+    /**
+      * @expectedException Codeception\Exception\TestParseException
+      */
+    public function testExceptionTestFileInvalid()
+    {
+      $model = codecept_data_dir().'notagrapfile.graphml';
+      $graphwalker = new  GraphWalker([
+                            'path' => 'tests/_data/',
+                            'graphwalker' => [
+                              'algorithm' => 'Graphp\Algorithms\ShortestPath\Dijkstra'
+                            ]
+                          ]);
+      $graphwalker->loadTests($model);
+      $this->assertInstanceOf('\Fhaculty\Graph\Graph',$graphwalker->getGraph());
+      $tests = $graphwalker->getTests();
+    }
+
 }