VB -> C#: Language version seems to be ignored in some cases (C# 7 feature is used in C# 6 conversion request)

[N-Olbert]

VB.Net input code

Public Function Foo(x As Decimal) As Decimal
    If (x > "0") Then
	    Return x * "30,56" 
    End If
    Return Nothing 
End Function

Erroneous output

public decimal Foo(decimal x)
{
    if ((double)x > Conversions.ToDouble("0"))
    {
        return (decimal)((double)x * Conversions.ToDouble("30,55"));
    }

    return default; // NOTE: default is a C# 7 feature
}

Expected output

public decimal Foo(decimal x)
{
    if ((double)x > Conversions.ToDouble("0"))
    {
        return (decimal)((double)x * Conversions.ToDouble("30,55"));
    }

    return default(decimal); // NOTE: default(decimal) (this works in C# 6)
}

Converter code

var conversionOptions = new CodeWithOptions(code)
                                                .SetFromLanguage(LanguageNames.VisualBasic, 14)
                                                .SetToLanguage(LanguageNames.CSharp, 6) // NOTE: Language version is set to 6
                                                .WithTypeReferences(references);
var conversationResult = await CodeConverter.ConvertAsync(conversionOptions)

Details

• Product in use: NuGet-package "ICSharpCode.CodeConverter"
• Version in use: 8.5.0.374

[GrahamTheCoder]

I'm afraid the option to control the version (especially of the output) has only a small influence - it is not strictly adhered to. It probably should have been deprecated long ago. It's not really feasible to support multiple different language versions elegantly unfortunately. I'll leave this issue open to track deprecating the options so as not to mislead people!

What I'd recommend is to use a c#code formatter to reformat the result to your preferred style

[GrahamTheCoder]

Options will be removed in the next release (which will be a major version increment)