Add MockeryBar test

In order to test expects() in a more native way, as an inner dependency
of test under subject, lets add a Bar class that uses Foo and lets test
it

Author: msvrtan

tests/Mockery/Bar.php

@@ -0,0 +1,21 @@
+<?php declare(strict_types = 1);
+
+namespace PHPStan\Mockery;
+
+class Bar
+{
+
+	/** @var Foo */
+	private $foo;
+
+	public function __construct(Foo $foo)
+	{
+		$this->foo = $foo;
+	}
+
+	public function doFoo(): ?string
+	{
+		return $this->foo->doFoo();
+	}
+
+}

tests/Mockery/MockeryBarTest.php

@@ -0,0 +1,24 @@
+<?php declare(strict_types = 1);
+
+namespace PHPStan\Mockery;
+
+class MockeryBarTest extends \PHPUnit\Framework\TestCase
+{
+
+	/** @var \Mockery\MockInterface|Foo */
+	private $fooMock;
+
+	protected function setUp(): void
+	{
+		$this->fooMock = \Mockery::mock(Foo::class);
+	}
+
+	public function testFooIsCalled(): void
+	{
+		$bar = new Bar($this->fooMock);
+
+		$this->fooMock->expects()->doFoo()->andReturn('foo');
+		self::assertSame('foo', $bar->doFoo());
+	}
+
+}