Add Unit Test to test the test setup

Test/Unit/Model/ConfigTest.php

@@ -0,0 +1,94 @@
+<?php
+
+declare(strict_types=1);
+
+namespace MageOS\GraphQlPlayground\Test\Unit\Model;
+
+use Magento\Framework\App\Config\ScopeConfigInterface;
+use Magento\Framework\App\State;
+use Magento\Store\Api\Data\StoreInterface;
+use Magento\Store\Model\ScopeInterface;
+use MageOS\GraphQlPlayground\Model\Config;
+use PHPUnit\Framework\TestCase;
+
+class ConfigTest extends TestCase
+{
+    /**
+     * @var State |\PHPUnit\Framework\MockObject\MockObject
+     */
+    private State $stateMock;
+
+    /**
+     * @var ScopeConfigInterface|\PHPUnit\Framework\MockObject\MockObject
+     */
+    private $scopeConfigMock;
+
+    /**
+     * @var Config
+     */
+    private $sut;
+
+    protected function setUp(): void
+    {
+        $this->stateMock = $this->createMock(State::class);
+        $this->scopeConfigMock = $this->createMock(ScopeConfigInterface::class);
+
+        $this->sut = new Config(
+            $this->stateMock,
+            $this->scopeConfigMock,
+        );
+    }
+
+    public function testIsEnabledInDeveloperMode(): void
+    {
+        $this->stateMock->expects($this->once())
+            ->method('getMode')
+            ->willReturn(State::MODE_DEVELOPER);
+
+        $this->scopeConfigMock->expects($this->never())->method('isSetFlag');
+
+        $this->assertTrue(
+            $this->sut->isEnabled(
+                $this->createMock(StoreInterface::class)
+            )
+        );
+    }
+
+    public function testIfIsEnabledBySettingTheRightConfig()
+    {
+        $this->stateMock->expects($this->once())
+            ->method('getMode')
+            ->willReturn(State::MODE_PRODUCTION);
+
+        $this->scopeConfigMock->expects($this->once())->method('isSetFlag')->with(
+            'dev/graphiql/enabled_in_production',
+            ScopeInterface::SCOPE_STORE,
+            $this->createMock(StoreInterface::class)
+        )->willReturn(true);
+
+        $this->assertTrue(
+            $this->sut->isEnabled(
+                $this->createMock(StoreInterface::class)
+            )
+        );
+    }
+
+    public function testIfIsDisabledBySettingTheRightConfig()
+    {
+        $this->stateMock->expects($this->once())
+            ->method('getMode')
+            ->willReturn(State::MODE_PRODUCTION);
+
+        $this->scopeConfigMock->expects($this->once())->method('isSetFlag')->with(
+            'dev/graphiql/enabled_in_production',
+            ScopeInterface::SCOPE_STORE,
+            $this->createMock(StoreInterface::class)
+        )->willReturn(false);
+
+        $this->assertFalse(
+            $this->sut->isEnabled(
+                $this->createMock(StoreInterface::class)
+            )
+        );
+    }
+}