如何比較兩個MemoryStream與FluentAssertions

Question

使用FluentAssertion 3.1.229，你如何比較兩個不同的MemoryStream的內容？

寫作actualStream.Should().Be(expectedStream);產生以下錯誤：

System.IO.MemoryStream 
{ 
    CanRead = True 
    CanSeek = True 
    CanTimeout = False 
    CanWrite = True 
    Capacity = 8 
    Length = 8 
    Position = 0 
    ReadTimeout = "[Property 'ReadTimeout' threw an exception: 'Exception has been thrown by the target of an invocation.']" 
    WriteTimeout = "[Property 'WriteTimeout' threw an exception: 'Exception has been thrown by the target of an invocation.']" 
}, but found 

System.IO.MemoryStream 
{ 
    CanRead = True 
    CanSeek = True 
    CanTimeout = False 
    CanWrite = True 
    Capacity = 8 
    Length = 8 
    Position = 0 
    ReadTimeout = "[Property 'ReadTimeout' threw an exception: 'Exception has been thrown by the target of an invocation.']" 
    WriteTimeout = "[Property 'WriteTimeout' threw an exception: 'Exception has been thrown by the target of an invocation.']" 
}. 

是的，我可以使用NUnit Assert.That(actualStream, Is.EqualTo(expectedStream));但有可能與FluentAssertions？

謝謝。

Answer 1

也許這會適合你嗎？

actualStream.ToArray().Should().Be(expectedStream.ToArray()); 

Answer 2

你NUnit的解決方案將不能工作，因爲MemoryStream的Equals實現並不做一個逐字節的比較。相反，使用

actualStream.GetBuffer().ShouldBeEquivalentTo(expectedStream.GetBuffer())。

GetBuffer返回對內部字節數組的引用並在其上調用Should().Be()將導致集合斷言進行逐字節比較。