Simplify Factory test by utilising a PSR container stub

Signed-off-by: George Steel <george@net-glue.co.uk>

Author: gsteel

test/AppTest/Handler/HomePageHandlerFactoryTest.php

@@ -6,73 +6,32 @@
 
 use App\Handler\HomePageHandler;
 use App\Handler\HomePageHandlerFactory;
+use AppTest\InMemoryContainer;
 use Mezzio\Router\RouterInterface;
 use Mezzio\Template\TemplateRendererInterface;
-use PHPUnit\Framework\MockObject\MockObject;
 use PHPUnit\Framework\TestCase;
-use Psr\Container\ContainerInterface;
-
-use function in_array;
 
 class HomePageHandlerFactoryTest extends TestCase
 {
-    /** @var ContainerInterface&MockObject */
-    protected $container;
-
-    /** @var RouterInterface&MockObject */
-    protected $router;
-
-    protected function setUp(): void
-    {
-        $this->container = $this->createMock(ContainerInterface::class);
-        $this->router    = $this->createMock(RouterInterface::class);
-    }
-
     public function testFactoryWithoutTemplate(): void
     {
-        $this->container
-            ->expects($this->once())
-            ->method('has')
-            ->with(TemplateRendererInterface::class)
-            ->willReturn(false);
-        $this->container
-            ->expects($this->once())
-            ->method('get')
-            ->with(RouterInterface::class)
-            ->willReturn($this->router);
+        $container = new InMemoryContainer();
+        $container->setService(RouterInterface::class, $this->createMock(RouterInterface::class));
 
         $factory  = new HomePageHandlerFactory();
-        $homePage = $factory($this->container);
+        $homePage = $factory($container);
 
         self::assertInstanceOf(HomePageHandler::class, $homePage);
     }
 
     public function testFactoryWithTemplate(): void
     {
-        $renderer = $this->createMock(TemplateRendererInterface::class);
-        $this->container
-            ->expects($this->once())
-            ->method('has')
-            ->with(TemplateRendererInterface::class)
-            ->willReturn(true);
-        $this->container
-            ->expects($this->exactly(2))
-            ->method('get')
-            ->with(self::callback(static function (string $name): bool {
-                self::assertTrue(in_array($name, [
-                    RouterInterface::class,
-                    TemplateRendererInterface::class,
-                ]));
-
-                return true;
-            }))
-            ->willReturnOnConsecutiveCalls(
-                $this->router,
-                $renderer
-            );
+        $container = new InMemoryContainer();
+        $container->setService(RouterInterface::class, $this->createMock(RouterInterface::class));
+        $container->setService(TemplateRendererInterface::class, $this->createMock(TemplateRendererInterface::class));
 
         $factory  = new HomePageHandlerFactory();
-        $homePage = $factory($this->container);
+        $homePage = $factory($container);
 
         self::assertInstanceOf(HomePageHandler::class, $homePage);
     }

test/AppTest/InMemoryContainer.php

@@ -0,0 +1,47 @@
+<?php
+
+declare(strict_types=1);
+
+namespace AppTest;
+
+use Psr\Container\ContainerInterface;
+use RuntimeException;
+
+use function array_key_exists;
+use function sprintf;
+
+/**
+ * A PSR Container stub. Useful for testing factories without excessive mocking
+ */
+class InMemoryContainer implements ContainerInterface
+{
+    /** @var array<string, mixed> */
+    public array $services = [];
+
+    public function setService(string $name, mixed $service): void
+    {
+        $this->services[$name] = $service;
+    }
+
+    /**
+     * @param string $id
+     * @return mixed
+     */
+    public function get($id)
+    {
+        if (! $this->has($id)) {
+            throw new RuntimeException(sprintf('Service not found "%s"', $id));
+        }
+
+        return $this->services[$id];
+    }
+
+    /**
+     * @param string $id
+     * @return bool
+     */
+    public function has($id)
+    {
+        return array_key_exists($id, $this->services);
+    }
+}