Small refactoring. Covering the SetWeeeRendererInFormObserver class by Unit Test

Author: eduard13

app/code/Magento/Weee/Test/Unit/Observer/AddPaymentWeeeItemTest.php

@@ -60,11 +60,11 @@ protected function setUp()
      * Test execute
      *
      * @dataProvider dataProvider
-     * @param $isEnabled
-     * @param $includeInSubtotal
+     * @param bool $isEnabled
+     * @param bool $includeInSubtotal
      * @return void
      */
-    public function testExecute($isEnabled, $includeInSubtotal): void
+    public function testExecute(bool $isEnabled, bool $includeInSubtotal): void
     {
         /** @var Observer|MockObject $observerMock */
         $observerMock = $this->createMock(Observer::class);
@@ -122,8 +122,8 @@ public function dataProvider(): array
     /**
      * Prepare if FPT should be added to payment cart as custom item or not.
      *
-     * @param $isEnabled
-     * @param $includeInSubtotal
+     * @param bool $isEnabled
+     * @param bool $includeInSubtotal
      * @return bool
      */
     private function prepareShouldBeAddedAsCustomItem(bool $isEnabled, bool $includeInSubtotal): bool

app/code/Magento/Weee/Test/Unit/Observer/SetWeeeRendererInFormObserverTest.php

@@ -0,0 +1,88 @@
+<?php
+/**
+ * Copyright © Magento, Inc. All rights reserved.
+ * See COPYING.txt for license details.
+ */
+declare(strict_types=1);
+
+namespace Magento\Weee\Test\Unit\Observer;
+
+use Magento\Framework\Data\Form;
+use Magento\Framework\Event;
+use Magento\Framework\Event\Observer;
+use Magento\Framework\View\LayoutInterface;
+use Magento\Weee\Model\Tax;
+use Magento\Weee\Observer\SetWeeeRendererInFormObserver;
+use PHPUnit\Framework\TestCase;
+use PHPUnit_Framework_MockObject_MockObject as MockObject;
+
+/**
+ * Class AddPaymentWeeeItemTest
+ */
+class SetWeeeRendererInFormObserverTest extends TestCase
+{
+    /**
+     * Testable object
+     *
+     * @var SetWeeeRendererInFormObserver
+     */
+    private $observer;
+
+    /**
+     * @var LayoutInterface|MockObject
+     */
+    private $layoutMock;
+
+    /**
+     * @var Tax|MockObject
+     */
+    private $taxModelMock;
+
+    /**
+     * Set Up
+     */
+    protected function setUp()
+    {
+        $this->layoutMock = $this->createMock(LayoutInterface::class);
+        $this->taxModelMock = $this->createMock(Tax::class);
+        $this->observer = new SetWeeeRendererInFormObserver(
+            $this->layoutMock,
+            $this->taxModelMock
+        );
+    }
+
+    /**
+     * Test assigning a custom renderer for product create/edit form weee attribute element
+     *
+     * @return void
+     */
+    public function testExecute(): void
+    {
+        $attributes = new \ArrayIterator(['element_code_1', 'element_code_2']);
+        /** @var Event|MockObject $eventMock */
+        $eventMock = $this->getMockBuilder(Event::class)
+            ->disableOriginalConstructor()
+            ->setMethods(['getForm'])
+            ->getMock();
+
+        /** @var Observer|MockObject $observerMock */
+        $observerMock = $this->createMock(Observer::class);
+        /** @var Form|MockObject $formMock */
+        $formMock = $this->createMock(Form::class);
+
+        $eventMock->expects($this->once())
+            ->method('getForm')
+            ->willReturn($formMock);
+        $observerMock->expects($this->once())
+            ->method('getEvent')
+            ->willReturn($eventMock);
+        $this->taxModelMock->expects($this->once())
+            ->method('getWeeeAttributeCodes')
+            ->willReturn($attributes);
+        $formMock->expects($this->exactly($attributes->count()))
+            ->method('getElement')
+            ->willReturnSelf();
+
+        $this->observer->execute($observerMock);
+    }
+}