added tests and readme

Author: dmitrykazak

README.md

@@ -37,6 +37,12 @@ Magento 2 Custom Option Default Value extension use to set custom option default
 * Radio Box
 * Checkbox
 
+![Configuration](https://user-images.githubusercontent.com/5670207/73607519-005b9880-45c8-11ea-8b6c-eb7251a8d985.png)
+
+![Setting Custom Option of Product](https://user-images.githubusercontent.com/5670207/73607472-5976fc80-45c7-11ea-8398-b75a3fb593f8.png)
+
+![Product Page](https://user-images.githubusercontent.com/5670207/73607439-1157da00-45c7-11ea-9f4e-4e00763d3e6e.png)
+
 #### Support
  If you encounter any problems or bugs, please open an [issue](https://github.com/dmitrykazak/magento2-custom-option-default-value/issues) on GitHub.
 

Test/Unit/Model/ConfigTest.php

@@ -0,0 +1,51 @@
+<?php
+
+declare(strict_types=1);
+
+namespace DK\CustomOptionDefaultValue\Test\Unit\Model;
+
+use DK\CustomOptionDefaultValue\Model\Config;
+use Magento\Framework\App\Config\ScopeConfigInterface;
+use PHPUnit\Framework\MockObject\MockObject;
+use PHPUnit\Framework\TestCase;
+
+/**
+ * @internal
+ * @coversNothing
+ */
+final class ConfigTest extends TestCase
+{
+    /**
+     * @var MockObject|ScopeConfigInterface
+     */
+    private $scopeConfig;
+
+    /**
+     * @var Config
+     */
+    private $config;
+
+    protected function setUp(): void
+    {
+        parent::setUp();
+
+        $this->scopeConfig = $this->createMock(ScopeConfigInterface::class);
+        $this->config = new Config($this->scopeConfig);
+    }
+
+    public function testIsActiveModule(): void
+    {
+        $this->scopeConfig
+            ->expects($this->once())
+            ->method('isSetFlag')
+            ->with($this->getConstValue('XML_PATH_GENERAL_ACTIVE')->getValue())
+            ->willReturn(true);
+
+        $this->assertTrue($this->config->isActiveModule());
+    }
+
+    private function getConstValue(string $const): \ReflectionClassConstant
+    {
+        return new \ReflectionClassConstant(Config::class, $const);
+    }
+}

Test/Unit/Plugin/Catalog/Block/Product/View/Options/Type/SelectTest.php

@@ -0,0 +1,102 @@
+<?php
+
+declare(strict_types=1);
+
+namespace DK\CustomOptionDefaultValue\Test\Unit\Plugin\Catalog\Block\Product\View\Options\Type;
+
+use DK\CustomOptionDefaultValue\Block\Product\View\Options\Type\Select\CheckableFactory;
+use DK\CustomOptionDefaultValue\Block\Product\View\Options\Type\Select\Multiple;
+use DK\CustomOptionDefaultValue\Block\Product\View\Options\Type\Select\MultipleFactory;
+use DK\CustomOptionDefaultValue\Model\Config;
+use DK\CustomOptionDefaultValue\Plugin\Catalog\Block\Product\View\Options\Type\Select;
+use Magento\Catalog\Block\Product\View\Options\Type\Select as TypeSelect;
+use Magento\Catalog\Model\Product;
+use PHPUnit\Framework\MockObject\MockObject;
+use PHPUnit\Framework\TestCase;
+
+/**
+ * @internal
+ * @coversNothing
+ */
+class SelectTest extends TestCase
+{
+    /**
+     * @var MockObject|MultipleFactory
+     */
+    private $multipleFactory;
+
+    /**
+     * @var CheckableFactory|MockObject
+     */
+    private $checkableFactory;
+
+    /**
+     * @var Config|MockObject
+     */
+    private $config;
+
+    /**
+     * @var Select
+     */
+    private $plugin;
+
+    /**
+     * @var MockObject|TypeSelect
+     */
+    private $typeSelectMock;
+
+    protected function setUp(): void
+    {
+        parent::setUp();
+
+        $this->multipleFactory = $this->createPartialMock(MultipleFactory::class, ['create']);
+        $this->checkableFactory = $this->createPartialMock(CheckableFactory::class, ['create']);
+        $this->config = $this->createMock(Config::class);
+
+        $this->typeSelectMock = $this->createMock(TypeSelect::class);
+
+        $this->plugin = new Select($this->multipleFactory, $this->checkableFactory, $this->config);
+    }
+
+    public function testAroundGetValuesHtml(): void
+    {
+        $proceed = function () {
+            return null;
+        };
+
+        $this->config->expects(self::once())->method('isActiveModule')->willReturn(true);
+
+        /** @var \Magento\Catalog\Model\Product\Option|MockObject $option */
+        $option = $this->createMock(\Magento\Catalog\Model\Product\Option::class);
+        $option->expects(self::once())->method('getType')->willReturn(\Magento\Catalog\Api\Data\ProductCustomOptionInterface::OPTION_TYPE_DROP_DOWN);
+
+        /** @var MockObject|Product $product */
+        $product = $this->createMock(Product::class);
+
+        $this->typeSelectMock->expects(self::once())->method('getOption')->willReturn($option);
+        $this->typeSelectMock->expects(self::once())->method('getProduct')->willReturn($product);
+
+        $multipleMock = $this->createPartialMock(Multiple::class, [
+            'setOption', 'setProduct', 'setSkipJsReloadPrice', 'toHtml',
+        ]);
+        $multipleMock->method('setOption')->willReturn($multipleMock);
+        $multipleMock->method('setProduct')->willReturn($multipleMock);
+        $multipleMock->method('setSkipJsReloadPrice')->willReturn($multipleMock);
+
+        $this->multipleFactory->expects(self::once())->method('create')->willReturn($multipleMock);
+
+        $this->plugin->aroundGetValuesHtml($this->typeSelectMock, $proceed);
+    }
+
+    public function testAroundGetValuesHtmlModuleDisabled(): void
+    {
+        $proceed = function () {
+            return null;
+        };
+
+        $this->config->expects(self::once())->method('isActiveModule')->willReturn(false);
+        $this->typeSelectMock->expects(self::never())->method('getOption');
+
+        $this->plugin->aroundGetValuesHtml($this->typeSelectMock, $proceed);
+    }
+}