exception in errorlist

[jnyrup]

I get several exceptions in the error list:
The stack traces seems to be identical for all of them, see below for one of them.
A lot of the analyzers mentioned in the stack traces don't seem to apply for my test method?

I haven't been able to come up with an example that triggers the bug.
Any ideas?

Severity	Code	Description	Project	File	Line	Suppression State	Detail Description
Warning	AD0001	Analyzer 'FluentAssertions.BestPractices.CollectionShouldEqualOtherCollectionByComparerAnalyzer' threw an exception of type 'System.ArgumentException' with message 'An item with the same key has already been added.'.	CIUnitTests		1	Active	Analyzer 'FluentAssertions.BestPractices.CollectionShouldEqualOtherCollectionByComparerAnalyzer' threw the following exception:
'Exception occurred with following context:
Compilation: CIUnitTests
ISymbol: MyTest (Method)
SyntaxTree: C:\Test.cs
SyntaxNode: [TestMethod] public void MyTest ... [MethodDeclarationSyntax]@[8641..10638) (200,8)-(232,9)

System.ArgumentException: An item with the same key has already been added.
   at System.ThrowHelper.ThrowArgumentException(ExceptionResource resource)
   at System.Collections.Generic.Dictionary`2.Insert(TKey key, TValue value, Boolean add)
   at System.Collections.Generic.Dictionary`2.Add(TKey key, TValue value)
   at FluentAssertions.BestPractices.FluentAssertionsWithArgumentsCSharpSyntaxVisitor.VisitArguments(SeparatedSyntaxList`1 arguments)
   at FluentAssertions.BestPractices.FluentAssertionsWithArgumentsCSharpSyntaxVisitor.VisitArgumentList(ArgumentListSyntax node)
   at Microsoft.CodeAnalysis.CSharp.Syntax.ArgumentListSyntax.Accept(CSharpSyntaxVisitor visitor)
   at Microsoft.CodeAnalysis.CSharp.CSharpSyntaxVisitor.Visit(SyntaxNode node)
   at FluentAssertions.BestPractices.FluentAssertionsCSharpSyntaxVisitor.Visit(SyntaxNode node)
   at FluentAssertions.BestPractices.FluentAssertionsCSharpSyntaxVisitor.VisitInvocationExpression(InvocationExpressionSyntax node)
   at Microsoft.CodeAnalysis.CSharp.Syntax.InvocationExpressionSyntax.Accept(CSharpSyntaxVisitor visitor)
   at Microsoft.CodeAnalysis.CSharp.CSharpSyntaxVisitor.Visit(SyntaxNode node)
   at FluentAssertions.BestPractices.FluentAssertionsCSharpSyntaxVisitor.Visit(SyntaxNode node)
   at FluentAssertions.BestPractices.FluentAssertionsCSharpSyntaxVisitor.VisitExpressionStatement(ExpressionStatementSyntax node)
   at Microsoft.CodeAnalysis.CSharp.Syntax.ExpressionStatementSyntax.Accept(CSharpSyntaxVisitor visitor)
   at FluentAssertions.BestPractices.FluentAssertionsAnalyzer`1.AnalyzeExpressionStatement(ExpressionStatementSyntax statement)
   at FluentAssertions.BestPractices.FluentAssertionsAnalyzer`1.AnalyzeCodeBlock(CodeBlockAnalysisContext context)
   at Microsoft.CodeAnalysis.Diagnostics.AnalyzerExecutor.<>c__48`2.<ExecuteBlockActions>b__48_0(ValueTuple`2 data)
   at Microsoft.CodeAnalysis.Diagnostics.AnalyzerExecutor.ExecuteAndCatchIfThrows_NoLock[TArg](DiagnosticAnalyzer analyzer, Action`1 analyze, TArg argument, Nullable`1 info)
-----
'.

[Meir017]

this following line throw https://github.com/fluentassertions/fluentassertions.analyzers/blob/master/src/FluentAssertions.Analyzers/Utilities/FluentAssertionsWithArgumentsCSharpSyntaxVisitor.cs#L31

maybe you are chaining multiple methods with the same name and both of the method calls have arguments?

[jnyrup]

Heureka!

public class MyClass
    {
        public string Message { get; }
    }

    class Class1
    {
        [TestMethod]
        public void MyTestMethod()
        {
            var details = new List<MyClass>();

            details.Should().Contain(d => d.Message.Contains("a"))
                .And.Contain(d => d.Message.Contains("c"));
        }
    }

[Meir017]

I had a feeling it's something like this...

Looks like another redesign to the FluentAssertionsWithArgumentsCSharpSyntaxVisitor class which extracts the methods into a dictionary containing for each method its arguments.

I'm going to add a SanityTests class (not sure about the name yet) that will include cases the should not throw exceptions (and no diagnostics), this will help

[jnyrup]

Be careful with flattening the syntax tree in any way.

var nestedList = new List<List<int>>();

nestedList.Should().NotBeNull()
    .And.ContainSingle()
        .Which.Should().NotBeEmpty();

is currently simplified into:

nestedList.Should().NotBeNullOrEmpty()
                .And.ContainSingle()
                    .Which.Should();

[Meir017]

looks like the Should could be used as some kind of separators when looking for a sequence of method calls, does this make sense?

[jnyrup]

As of Fluent Assertions 5.0, I guess you should be able to do so.
The API has been changed, so all assertions now start with Should().
E.g. ShouldThrow() and ShouldBeEquivalent() are now Should().Throw() and Should().BeEquivalent().

Most assertions return an AndConstraint which is a continutation on the same assertions.
Others return an AndWhichConstraint which allows you to either continue on the same assertion (the And part) or begin an assertion on some result from the assertions.
There is also WhichValueConstraint.

E.g. ContainSingle() return and AndWhich which lets you assert on that single element.