Add unit test to reproduce issue #3254

tests/unit/TextUI/TestRunnerTest.php

@@ -0,0 +1,49 @@
+<?php
+/*
+ * This file is part of PHPUnit.
+ *
+ * (c) Sebastian Bergmann <sebastian@phpunit.de>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+namespace PHPUnit\TextUI;
+
+use PHPUnit\Framework\TestCase;
+
+class TestRunnerTest extends TestCase
+{
+    public function testTestIsRunnable()
+    {
+        $runner = new TestRunner();
+        $runner->setPrinter($this->getResultPrinterMock());
+        $runner->doRun(new \Success(), ['filter' => 'foo'], false);
+    }
+
+    public function testSuiteIsRunnable()
+    {
+        $runner = new TestRunner();
+        $runner->setPrinter($this->getResultPrinterMock());
+        $runner->doRun($this->getSuiteMock(), ['filter' => 'foo'], false);
+    }
+
+    /**
+     * @return \PHPUnit\TextUI\ResultPrinter
+     */
+    private function getResultPrinterMock()
+    {
+        return $this->createMock(\PHPUnit\TextUI\ResultPrinter::class);
+    }
+
+    /**
+     * @return \PHPUnit\Framework\TestSuite
+     */
+    private function getSuiteMock()
+    {
+        $suite = $this->createMock(\PHPUnit\Framework\TestSuite::class);
+        $suite->expects($this->once())->method('injectFilter');
+        $suite->expects($this->once())->method('run');
+
+        return $suite;
+    }
+}