Merge pull request #1 from WeareJH/retrieve-child-deps

Allow to retrieve child mocks after creating an object

README.md

@@ -52,3 +52,42 @@ class ExampleTest extends TestCase
 
 ```
 
+Note that you can pass your own arguments to the object you want to create, in-case you want to pass real instances 
+or your own mocks. You pass them as a key value array where the key is the object constructor's parameter name you want 
+to override and the value is the actual value.
+
+`getObject` will read the object constructor parameters and automatically create mock objects using the class type of the
+parameter. It will then create the object you asked for passing in all the mocks via the constructor.
+
+You can also retrieve one of mocked dependencies after the object was created like so:
+
+```php
+<?php
+
+use PHPUnit\Framework\TestCase;
+use Magento\Framework\App\Action\Context;
+use Magento\Framework\App\Request\Http;
+use Magento\Framework\Message\ManagerInterface;
+use Jh\UnitTestHelpers\ObjectHelper;
+
+/**
+ * @author email@example.com
+ */
+class ExampleTest extends TestCase
+{
+    use ObjectHelper;
+
+
+    public function setup()
+    {
+
+        $context = $this->getObject(Context::class);
+
+        $request = $this->retrieveChildMock(Context::class, 'request');
+    }
+}
+```
+
+Where `request` is the constructor parameter name in `Context::class` - this method will return you the object prophecy
+so you can create expectations on it.
+

src/ObjectHelper.php

@@ -7,12 +7,29 @@
  */
 trait ObjectHelper
 {
+    private $mockRegistry = [];
+
     public function getObject(string $className, array $arguments = [])
     {
         $constructArguments = $this->getConstructorArguments($className, $arguments);
         return new $className(...array_values($constructArguments));
     }
 
+    public function retrieveChildMock(string $className, string $parameterName)
+    {
+        if (!isset($this->mockRegistry[$className][$parameterName])) {
+            throw new \RuntimeException(
+                sprintf(
+                    'No object parameter named: "%s" was created for object: "%s"',
+                    $parameterName,
+                    $className
+                )
+            );
+        }
+
+        return $this->mockRegistry[$className][$parameterName];
+    }
+
     private function getConstructorArguments(string $className, array $arguments = [])
     {
         $constructArguments = [];
@@ -38,16 +55,18 @@ private function getConstructorArguments(string $className, array $arguments = [
 
             if ($parameter->getClass()) {
                 $argClassName = $parameter->getClass()->getName();
-                $object       = $this->getMockObject($argClassName, $arguments);
+                $object       = $this->prophesize($argClassName);
+
+                //store this dep for later so we can retrieve it
+                if (!isset($this->mockRegistry[$className])) {
+                    $this->mockRegistry[$className] = [];
+                }
+
+                $this->mockRegistry[$className][$parameterName] = $object;
             }
 
-            $constructArguments[$parameterName] = null === $object ? $defaultValue : $object;
+            $constructArguments[$parameterName] = null === $object ? $defaultValue : $object->reveal();
         }
         return $constructArguments;
     }
-
-    private function getMockObject(string $className, $arguments)
-    {
-        return $this->prophesize($className)->reveal();
-    }
 }