Add test case for ConsoleInput::dataAvailable().

tests/TestCase/Console/ConsoleInputTest.php

@@ -0,0 +1,46 @@
+<?php
+/**
+ * CakePHP :  Rapid Development Framework (https://cakephp.org)
+ * Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
+ *
+ * Licensed under The MIT License
+ * For full copyright and license information, please see the LICENSE.txt
+ * Redistributions of files must retain the above copyright notice.
+ *
+ * @copyright     Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
+ * @link          https://cakephp.org CakePHP Project
+ * @since         3.7.3
+ * @license       https://opensource.org/licenses/mit-license.php MIT License
+ */
+namespace Cake\Test\TestCase\Console;
+
+use Cake\Console\ConsoleInput;
+use Cake\TestSuite\TestCase;
+
+/**
+ * ConsoleInput test.
+ */
+class ConsoleInputTest extends TestCase
+{
+    /**
+     * setUp method
+     *
+     * @return void
+     */
+    public function setUp()
+    {
+        parent::setUp();
+
+        $this->in = new ConsoleInput();
+    }
+
+    /**
+     * Test dataAvailable method
+     *
+     * @return void
+     */
+    public function testDataAvailable()
+    {
+        $this->assertFalse($this->in->dataAvailable());
+    }
+}