private static SyntaxNode CreateNonFlagsEnumConstantValue(INamedTypeSymbol enumType, object constantValue)
{
var underlyingSpecialType = enumType.EnumUnderlyingType.SpecialType;
var constantValueULong = EnumUtilities.ConvertEnumUnderlyingTypeToUInt64(constantValue, underlyingSpecialType);
// See if there's a member with this value. If so, then use that.
foreach (var member in enumType.GetMembers())
{
if (member.Kind == SymbolKind.Field)
{
var field = (IFieldSymbol)member;
if (field.HasConstantValue)
{
var fieldValue =
EnumUtilities.ConvertEnumUnderlyingTypeToUInt64(field.ConstantValue, underlyingSpecialType);
if (constantValueULong == fieldValue)
{
return(CreateMemberAccessExpression(field, enumType, underlyingSpecialType));
}
}
}
}
// Otherwise, just add the enum as a literal.
return(CreateExplicitlyCastedLiteralValue(enumType, underlyingSpecialType, constantValue));
}
private static SyntaxNode CreateExplicitlyCastedLiteralValue(
INamedTypeSymbol enumType,
SpecialType underlyingSpecialType,
object constantValue)
{
var expression = ExpressionGenerator.GenerateNonEnumValueExpression(
enumType.EnumUnderlyingType, constantValue, true);
var constantValueULong = EnumUtilities.ConvertEnumUnderlyingTypeToUInt64(constantValue, underlyingSpecialType);
if (constantValueULong == 0)
{
// 0 is always convertible to an enum type without needing a cast.
return(expression);
}
return(SyntaxFactory.CastExpression((TypeSyntax)enumType, expression.Parenthesize()));
}
