Suggest most similar module in missing module exception

* added suggestion on missing modules

* added one test

* changed expectException method

* changed hasModule to getModule

* fixed exception message

* Use string concatenation instead of variable interpolation

Because it was hard to read.

Co-authored-by: Gintautas Miselis <gintautas@miselis.lt>

Author: c33s

src/Codeception/Lib/ModuleContainer.php

@@ -22,6 +22,11 @@ class ModuleContainer
      */
     const MODULE_NAMESPACE = '\\Codeception\\Module\\';
 
+    /**
+     * @var integer
+     */
+    const MAXIMUM_LEVENSHTEIN_DISTANCE = 5;
+
     public static $packages = [
         'AMQP' => 'codeception/module-amqp',
         'Apc' => 'codeception/module-apc',
@@ -275,12 +280,37 @@ public function hasModule($moduleName)
     public function getModule($moduleName)
     {
         if (!$this->hasModule($moduleName)) {
-            throw new ModuleException(__CLASS__, "Module $moduleName couldn't be connected");
+            $this->throwMissingModuleExceptionWithSuggestion(__CLASS__, $moduleName);
         }
 
         return $this->modules[$moduleName];
     }
 
+    public function throwMissingModuleExceptionWithSuggestion($className, $moduleName)
+    {
+        $suggestedModuleNameInfo = $this->getModuleSuggestion($moduleName);
+        throw new ModuleException($className, "Module $moduleName couldn't be connected" . $suggestedModuleNameInfo);
+    }
+
+    protected function getModuleSuggestion($missingModuleName)
+    {
+        $shortestLevenshteinDistance = null;
+        $suggestedModuleName = null;
+        foreach ($this->modules as $moduleName => $module) {
+            $levenshteinDistance = levenshtein($missingModuleName, $moduleName);
+            if ($shortestLevenshteinDistance === null || $levenshteinDistance <= $shortestLevenshteinDistance) {
+                $shortestLevenshteinDistance = $levenshteinDistance;
+                $suggestedModuleName = $moduleName;
+            }
+        }
+
+        if ($suggestedModuleName !== null && $shortestLevenshteinDistance <= self::MAXIMUM_LEVENSHTEIN_DISTANCE) {
+            return " (did you mean '$suggestedModuleName'?)";
+        }
+
+        return '';
+    }
+
     /**
      * Get the module for an action.
      *

src/Codeception/Module.php

@@ -337,7 +337,7 @@ protected function getModules()
     protected function getModule($name)
     {
         if (!$this->hasModule($name)) {
-            throw new Exception\ModuleException(__CLASS__, "Module $name couldn't be connected");
+            $this->moduleContainer->throwMissingModuleExceptionWithSuggestion(__CLASS__, $name);
         }
         return $this->moduleContainer->getModule($name);
     }

tests/unit/Codeception/Lib/ModuleContainerTest.php

@@ -1,6 +1,7 @@
 <?php
 namespace Codeception\Lib;
 
+use Codeception\Exception\ModuleException;
 use Codeception\Lib\Interfaces\ConflictsWithModule;
 use Codeception\Lib\Interfaces\DependsOnModule;
 use Codeception\Test\Unit;
@@ -376,6 +377,23 @@ public function testInjectModuleIntoHelper()
         $this->moduleContainer->create('Codeception\Lib\HelperModule');
         $this->moduleContainer->hasModule('Codeception\Lib\HelperModule');
     }
+
+    public function testSuggestMissingModule()
+    {
+        $correctModule = 'Codeception\Lib\HelperModule';
+        $wrongModule = 'Codeception\Lib\Helpamodule';
+
+        $config = ['modules' => [
+            'enabled' => [$correctModule],
+        ]];
+        $this->moduleContainer = new ModuleContainer(Stub::make('Codeception\Lib\Di'), $config);
+        $this->moduleContainer->create('Codeception\Lib\HelperModule');
+        
+        $message = "Codeception\Lib\ModuleContainer: Module $wrongModule couldn't be connected (did you mean '$correctModule'?)";
+        $this->expectException('\Codeception\Exception\ModuleException');
+        $this->expectExceptionMessage($message);
+        $this->moduleContainer->getModule($wrongModule);
+    }
 }
 
 class StubModule extends \Codeception\Module