After installing VS2012 Premium on a dev machine a unit test failed, so the developer fixed the issue. When the changes were pushed to TeamCity the unit test failed. The project has not changed other than the solution file being upgraded to be compatible with VS2012. It still targets .net framework 4.0
I’ve isolated the problem to an issue with unicode characters being escaped when calling Uri.ToString. The following code replicates the behavior.
Imports NUnit.Framework
<TestFixture()>
Public Class UriTest
<Test()>
Public Sub UriToStringUrlDecodes()
Dim uri = New Uri("http://www.example.org/test?helloworld=foo%B6bar")
Assert.AreEqual("http://www.example.org/test?helloworld=foo¶bar", uri.ToString())
End Sub
End Class
Running this in VS2010 on a machine that does not have VS2012 installed succeeds, running this in VS2010 on a machine with VS2012 installed fails. Both using the latest version of NCrunch and NUnit from NuGet.
The messages from the failed assert are
Expected string length 46 but was 48. Strings differ at index 42.
Expected: "http://www.example.org/test?helloworld=foo¶bar"
But was: "http://www.example.org/test?helloworld=foo%B6bar"
-----------------------------------------------------^
The documentation on MSDN for both .NET 4 and .NET 4.5 shows that ToString should not encode this character, meaning that the old behavior should be the correct one.
A String instance that contains the unescaped canonical representation of the Uri instance. All characters are unescaped except #, ?, and %.
After installing VS2012, that unicode character is being escaped.
The file version of System.dll on the machine with VS2012 is 4.0.30319.17929
The file version of System.dll on the build server is 4.0.30319.236
Ignoring the merits of why we are using uri.ToString(), what we are testing and any potential work around. Can anyone explain why this behavior seems to have changed, or is this a bug?
Edit, here is the C# version
using System;
using NUnit.Framework;
namespace SystemUriCSharp
{
[TestFixture]
public class UriTest
{
[Test]
public void UriToStringDoesNotEscapeUnicodeCharacters()
{
var uri = new Uri(@"http://www.example.org/test?helloworld=foo%B6bar");
Assert.AreEqual(@"http://www.example.org/test?helloworld=foo¶bar", uri.ToString());
}
}
}
A bit of further investigation, if I target .NET 4.0 or .NET 4.5 the tests fail, if I switch it to .NET 3.5 then it succeeds.
The change is related to problems with earlier .NET versions, which have now changed to become more compliant to the standards.
%B6is UTF-16, but according to the standards UTF-8 should be used in the Uri, meaning that it should be%C2%B6. So as%B6is not UTF-8 it is now correctly ignored and not decoded.More details from the connect report quoted in verbatim below.