public void ContentTypeOfTextPlainWithoutAlternativeContentTypeHeaderReturnsPlainText()
{
MimePart mimePart = CreateMimePart("Text", "Plain", "test.gz");
string contentType = _contentTypeProvider.GetContentType(mimePart);
Assert.That(contentType, Is.EqualTo(ContentType.TextPlain));
}
public void GetContentType_When_Null_Headers_Should_Throw_ArgumentNullException()
{
Assert.Throws <ArgumentNullException>(() => _underTest.GetContentType(null));
}