private static bool TryChangeType(ITypeSymbol targetType, object argumentValue)
{
var targetReflectionType = Type.GetType(
AttributeArgumentSyntaxExtensions.GetFullName(targetType), false);
if (targetReflectionType != null)
{
try
{
Convert.ChangeType(argumentValue, targetReflectionType, CultureInfo.InvariantCulture);
return(true);
}
catch (InvalidCastException)
{
return(false);
}
catch (FormatException)
{
return(false);
}
catch (OverflowException)
{
return(false);
}
}
else
{
return(false);
}
}
private static Type GetTargetReflectionType(ITypeSymbol targetType)
{
string assembly = ", " + targetType.ContainingAssembly.Identity.ToString();
string typeName = AttributeArgumentSyntaxExtensions.GetQualifiedTypeName(targetType);
// First try to get type using assembly-qualified name, and if that fails try to get type
// using only the type name qualified by its namespace.
// This is a hacky attempt to make it work for types that are forwarded in .NET Core, e.g.
// Double which exists in the System.Runtime assembly at design time and in
// System.Private.CorLib at runtime, so targetType.ContainingAssembly will denote the wrong
// assembly, System.Runtime. See e.g. the following comment
// https://github.com/dotnet/roslyn/issues/16211#issuecomment-373084209
var targetReflectionType = Type.GetType(typeName + assembly, false) ?? Type.GetType(typeName, false);
return(targetReflectionType);
}
internal static bool CanAssignTo(this AttributeArgumentSyntax @this, ITypeSymbol target, SemanticModel model)
{
//See https://github.com/nunit/nunit/blob/f16d12d6fa9e5c879601ad57b4b24ec805c66054/src/NUnitFramework/framework/Attributes/TestCaseAttribute.cs#L396
//for the reasoning behind this implementation.
Optional <object> possibleConstantValue = model.GetConstantValue(@this.Expression);
object argumentValue = null;
if (possibleConstantValue.HasValue)
{
argumentValue = possibleConstantValue.Value;
}
TypeInfo sourceTypeInfo = model.GetTypeInfo(@this.Expression);
ITypeSymbol argumentType = sourceTypeInfo.Type;
if (argumentType == null)
{
return(target.IsReferenceType ||
target.OriginalDefinition.SpecialType == SpecialType.System_Nullable_T);
}
else
{
var targetType = GetTargetType(target);
if (targetType.IsAssignableFrom(argumentType))
{
return(true);
}
else
{
var canConvert = false;
if (targetType.SpecialType == SpecialType.System_Int16 || targetType.SpecialType == SpecialType.System_Byte ||
targetType.SpecialType == SpecialType.System_Int64 ||
targetType.SpecialType == SpecialType.System_SByte || targetType.SpecialType == SpecialType.System_Double)
{
canConvert = argumentType.SpecialType == SpecialType.System_Int32;
}
else if (targetType.SpecialType == SpecialType.System_Decimal)
{
canConvert = argumentType.SpecialType == SpecialType.System_Double ||
argumentType.SpecialType == SpecialType.System_String ||
argumentType.SpecialType == SpecialType.System_Int32;
}
else if (targetType.SpecialType == SpecialType.System_DateTime)
{
canConvert = argumentType.SpecialType == SpecialType.System_String;
}
if (canConvert)
{
return(AttributeArgumentSyntaxExtensions.TryChangeType(targetType, argumentValue));
}
else if (argumentType.SpecialType == SpecialType.System_String &&
model.Compilation.GetTypeByMetadataName(typeof(TimeSpan).FullName).IsAssignableFrom(targetType))
{
canConvert = TimeSpan.TryParse(argumentValue as string, out _);
}
return(canConvert);
}
}
}
internal static bool CanAssignTo(this AttributeArgumentSyntax @this, ITypeSymbol target, SemanticModel model)
{
//See https://github.com/nunit/nunit/blob/master/src/NUnitFramework/framework/Attributes/TestCaseAttribute.cs#L363
//for the reasoning behind this implementation.
object argumentValue = null;
if (@this.Expression is LiteralExpressionSyntax)
{
argumentValue = (@this.Expression as LiteralExpressionSyntax).Token.Value;
}
TypeInfo sourceTypeInfo = model.GetTypeInfo(@this.Expression);
ITypeSymbol argumentType = sourceTypeInfo.Type;
if (sourceTypeInfo.Type == null)
{
return(target.IsReferenceType ||
target.OriginalDefinition.SpecialType == SpecialType.System_Nullable_T);
}
else
{
var targetType = GetTargetType(target);
if (targetType.IsAssignableFrom(argumentType))
{
return(true);
}
else
{
var canConvert = false;
if (targetType.SpecialType == SpecialType.System_Int16 || targetType.SpecialType == SpecialType.System_Byte ||
targetType.SpecialType == SpecialType.System_SByte || targetType.SpecialType == SpecialType.System_Double)
{
canConvert = argumentType.SpecialType == SpecialType.System_Int32;
}
else if (targetType.SpecialType == SpecialType.System_Decimal)
{
canConvert = argumentType.SpecialType == SpecialType.System_Double ||
argumentType.SpecialType == SpecialType.System_String ||
argumentType.SpecialType == SpecialType.System_Int32;
}
else if (targetType.SpecialType == SpecialType.System_DateTime)
{
canConvert = argumentType.SpecialType == SpecialType.System_String;
}
if (canConvert)
{
return(AttributeArgumentSyntaxExtensions.TryChangeType(targetType, argumentValue));
}
else if (argumentType.SpecialType == SpecialType.System_String &&
model.Compilation.GetTypeByMetadataName(typeof(TimeSpan).FullName).IsAssignableFrom(targetType))
{
var outValue = default(TimeSpan);
canConvert = TimeSpan.TryParse(argumentValue as string, out outValue);
}
return(canConvert);
}
}
}