public static async Task <Document> RefactorAsync(
Document document,
EnumMemberDeclarationSyntax enumMemberDeclaration,
CancellationToken cancellationToken)
{
SemanticModel semanticModel = await document.GetSemanticModelAsync(cancellationToken).ConfigureAwait(false);
IFieldSymbol enumMemberSymbol = semanticModel.GetDeclaredSymbol(enumMemberDeclaration, cancellationToken);
ImmutableArray <EnumFieldSymbolInfo> infos = EnumFieldSymbolInfo.CreateRange(enumMemberSymbol.ContainingType);
ExpressionSyntax value = enumMemberDeclaration.EqualsValue?.Value;
var info = new EnumFieldSymbolInfo(enumMemberSymbol);
List <EnumFieldSymbolInfo> values = info.Decompose(infos);
values.Sort((f, g) =>
{
if (f.IsComposite())
{
if (g.IsComposite())
{
return(((IComparable)f.Value).CompareTo((IComparable)g.Value));
}
else
{
return(-1);
}
}
else if (g.IsComposite())
{
return(1);
}
return(((IComparable)f.Value).CompareTo((IComparable)g.Value));
});
BinaryExpressionSyntax newValue = BitwiseOrExpression(values[0].ToIdentifierName(), values[1].ToIdentifierName());
for (int i = 2; i < values.Count; i++)
{
newValue = BitwiseOrExpression(newValue, values[i].ToIdentifierName());
}
newValue = newValue.WithFormatterAnnotation();
return(await document.ReplaceNodeAsync(value, newValue, cancellationToken).ConfigureAwait(false));
}
public static void AnalyzeNamedType(SymbolAnalysisContext context)
{
var enumSymbol = (INamedTypeSymbol)context.Symbol;
if (enumSymbol.TypeKind != TypeKind.Enum)
{
return;
}
if (!enumSymbol.HasAttribute(MetadataNames.System_FlagsAttribute))
{
return;
}
var infos = default(ImmutableArray <EnumFieldSymbolInfo>);
foreach (ISymbol member in enumSymbol.GetMembers())
{
if (member is IFieldSymbol fieldSymbol)
{
if (!fieldSymbol.HasConstantValue)
{
return;
}
var info = new EnumFieldSymbolInfo(fieldSymbol);
if (info.IsComposite())
{
var declaration = (EnumMemberDeclarationSyntax)info.Symbol.GetSyntax(context.CancellationToken);
ExpressionSyntax valueExpression = declaration.EqualsValue?.Value;
if (valueExpression != null &&
(valueExpression.IsKind(SyntaxKind.NumericLiteralExpression) ||
valueExpression
.DescendantNodes()
.Any(f => f.IsKind(SyntaxKind.NumericLiteralExpression))))
{
if (infos.IsDefault)
{
infos = EnumFieldSymbolInfo.CreateRange(enumSymbol);
if (infos.IsDefault)
{
return;
}
}
List <EnumFieldSymbolInfo> values = info.Decompose(infos);
if (values?.Count > 1)
{
context.ReportDiagnostic(
DiagnosticDescriptors.DeclareEnumValueAsCombinationOfNames,
valueExpression);
}
}
}
}
}
}
