Multi line markup location is not found when parsing source code

[Mrnikbobjeff]

For the posted source code no markup location is found. Instead I get a stacktrace and an Exception message:

Message: 
    System.InvalidOperationException : The markup location '#0' was not found in the input.
  Stack Trace: 
    DiagnosticResult.WithAppliedMarkupLocations(ImmutableDictionary`2 markupLocations) line 357
    SolutionState.WithProcessedMarkup(MarkupOptions markupOptions, DiagnosticDescriptor defaultDiagnostic, ImmutableArray`1 supportedDiagnostics, ImmutableArray`1 fixableDiagnostics, String defaultPath) line 276
    CodeFixTest`1.RunAsync(CancellationToken cancellationToken) line 232
    CSharpCodeFixVerifier`2.VerifyCodeFixAsync(String source, DiagnosticResult[] expected, String fixedSource) line 52
    CSharpCodeFixVerifier`2.VerifyCodeFixAsync(String source, DiagnosticResult expected, String fixedSource) line 41
    UseThrowIfCancellationRequestedTests.SingleFix_IfBlock() line 117
    --- End of stack trace from previous location where exception was thrown ---

[Fact]
        public async Task SingleFix_IfBlock()
        {
            await VerifyCS.VerifyCodeFixAsync(@"
    using System;
    using System.Threading.Tasks;
    using System.Threading;
    namespace ConsoleApplication1
    {
        class TypeName
        {   
            public async Task Test(CancellationToken ct)
            {
                {|#0:if(ct.IsCancellationRequested)
                {
                    throw new Exception();
                }|}
            }
        }
    }", VerifyCS.Diagnostic(UseThrowIfCancellationRequestedAnalyzer.DefaultRule).WithLocation(0),
            @"using System;
using System.Threading.Tasks;
using System.Threading;
namespace ConsoleApplication1
{
    class TypeName
    {
        public async Task Test(CancellationToken ct)
        {
            ct.ThrowIfCancellationRequested();
        }
    }
}");
        }

[sharwell]

My guess on the cause of this is the code fix provider specified in the alias for VerifyCS does not report UseThrowIfCancellationRequestedAnalyzer.DefaultRule as a supported diagnostic. This scenario would cause VerifyCodeFixAsync to expect the diagnostic in both the test code and the fixed code, but only the test code provides location 0.