assertTrue($subject->isValid()); } public function testIsValid_default_max() { $subject = new Position(7, 7); $this->assertTrue($subject->isValid()); } public function testIsValid_fileTooHigh() { $subject = new Position(8, 7); $this->assertFalse($subject->isValid()); } public function testIsValid_RankTooHigh() { $subject = new Position(7, 8); $this->assertFalse($subject->isValid()); } public function testIsValid_fileTooLow() { $subject = new Position(-1, 0); $this->assertFalse($subject->isValid()); } public function testIsValid_RankTooLow() { $subject = new Position(0, -1); $this->assertFalse($subject->isValid()); } public function testToString() { $subject = new Position(4, 5); $this->assertEquals("e6", strval($subject)); } }