public function testIfUnmodifiedSinceFromStringCreatesValidIfUnmodifiedSinceHeader()
 {
     $ifUnmodifiedSinceHeader = IfUnmodifiedSince::fromString('If-Unmodified-Since: Sun, 06 Nov 1994 08:49:37 GMT');
     $this->assertInstanceOf('Zend\\Http\\Header\\HeaderInterface', $ifUnmodifiedSinceHeader);
     $this->assertInstanceOf('Zend\\Http\\Header\\IfUnmodifiedSince', $ifUnmodifiedSinceHeader);
 }
 public function testIfUnmodifiedSinceFromStringCreatesValidIfUnmodifiedSinceHeader()
 {
     $ifUnmodifiedSinceHeader = IfUnmodifiedSince::fromString('If-Unmodified-Since: xxx');
     $this->assertInstanceOf('Zend\\Http\\Header\\HeaderDescription', $ifUnmodifiedSinceHeader);
     $this->assertInstanceOf('Zend\\Http\\Header\\IfUnmodifiedSince', $ifUnmodifiedSinceHeader);
 }