public function testToReadableString() { $ma0 = new MutableArray([]); $this->assertEquals('', $ma0->toReadableString(', ', ' and ')); $ma1 = new MutableArray(['a']); $this->assertEquals('a', $ma1->toReadableString(', ', ' and ')); $ma2 = new MutableArray(['a', 'b']); $this->assertEquals('a and b', $ma2->toReadableString(', ', ' and ')); $ma3 = new MutableArray(['a', 'b', 'c']); $this->assertEquals('a + b and c', $ma3->toReadableString(' + ', ' and ')); $ma4 = new MutableArray(['a', 'b', 'c', 'd']); $this->assertEquals('a, b, c or d', $ma4->toReadableString(', ', ' or ')); }