Examples of errors detected by the V3139 diagnostic

V3139. Two or more case-branches perform the same actions.

.NET Core Libraries (CoreFX)

V3139 Two or more case-branches perform the same actions. WMIGenerator.cs 5220

private static string
  ConvertToNumericValueAndAddToArray(....)
{
  string retFunctionName = string.Empty;
  enumType = string.Empty;

  switch(cimType)
  {
    case CimType.UInt8:
    case CimType.SInt8:
    case CimType.SInt16:
    case CimType.UInt16:
    case CimType.SInt32:
      arrayToAdd.Add(System.Convert.ToInt32(
                       numericValue,
                       (IFormatProvider)CultureInfo.InvariantCulture
                                                   .GetFormat(typeof(int))));
      retFunctionName = "ToInt32";
      enumType = "System.Int32";
      break;

    case CimType.UInt32:
      arrayToAdd.Add(System.Convert.ToInt32(
                       numericValue,
                       (IFormatProvider)CultureInfo.InvariantCulture
                                                   .GetFormat(typeof(int))));
      retFunctionName = "ToInt32";
      enumType = "System.Int32";
      break;
    }
    return retFunctionName;
}

.NET Core Libraries (CoreFX)

V3139 Two or more case-branches perform the same actions. ColorTranslator.cs 302

switch (c.ToKnownColor())
{
  ....
  case KnownColor.Control:
    colorString = "buttonface";
    break;
  case KnownColor.ControlLight:
    colorString = "buttonface";
    break;
  ....
}

Roslyn Analyzers

V3139 Two or more case-branches perform the same actions. CodeMetricsAnalyzer.cs 251

static bool isApplicableByDefault(string ruleId, SymbolKind symbolKind)
{
  switch (ruleId)
  {
     ....
     case CA1505RuleId:
       switch (symbolKind)
       {
          case SymbolKind.NamedType:
          case SymbolKind.Method:
          case SymbolKind.Field:
          case SymbolKind.Property:
          case SymbolKind.Event:
            return true;
          default:
            return false;
       }
     case CA1506RuleId:
       switch (symbolKind)
       {
          case SymbolKind.NamedType:
          case SymbolKind.Method:
          case SymbolKind.Field:
          case SymbolKind.Property:
          case SymbolKind.Event:
            return true;
          default:
            return false;
       }
     default:
       throw new NotImplementedException();
  }
}

Orchard CMS

V3139 Two or more case-branches perform the same actions. SerialDocumentExecuter.cs 23

public class SerialDocumentExecuter : DocumentExecuter
{
  private static IExecutionStrategy ParallelExecutionStrategy
    = new ParallelExecutionStrategy();
  private static IExecutionStrategy SerialExecutionStrategy
    = new SerialExecutionStrategy();
  private static IExecutionStrategy SubscriptionExecutionStrategy
    = new SubscriptionExecutionStrategy();

  protected override IExecutionStrategy SelectExecutionStrategy(....)
  {
    switch (context.Operation.OperationType)
    {
      case OperationType.Query:
        return SerialExecutionStrategy;

      case OperationType.Mutation:
        return SerialExecutionStrategy;

      case OperationType.Subscription:
        return SubscriptionExecutionStrategy;

      default:
        throw ....;
    }
  }
}

Open XML SDK

V3139 Two or more case-branches perform the same actions. OpenXmlPartReader.cs 560

private void InnerSkip()
{
    Debug.Assert(_xmlReader != null);

    switch (_elementState)
    {
        case ElementState.Null:
            ThrowIfNull();
            break;

        case ElementState.EOF:
            return;

        case ElementState.Start:
            _xmlReader.Skip();
            _elementStack.Pop();
            GetElementInformation();
            return;

        case ElementState.End:
        case ElementState.MiscNode:
            // cursor is end element, pop stack
            _xmlReader.Skip();
            _elementStack.Pop();
            GetElementInformation();
            return;
        ....
    }
    ....
}

Similar errors can be found in some other places:

• V3139 Two or more case-branches perform the same actions. OpenXmlMiscNode.cs 312
• V3139 Two or more case-branches perform the same actions. CustomPropertyPartTypeInfo.cs 30
• V3139 Two or more case-branches perform the same actions. CustomXmlPartTypeInfo.cs 15
• And 1 additional diagnostic messages.

QuantConnect Lean

V3139 Two or more case-branches perform the same actions. SecurityCacheTests.cs 510

public string[] GetPropertiesBy(SecuritySeedData type)
{
  switch (type)
  {
    case SecuritySeedData.None:
      return new string[0];

    case SecuritySeedData.OpenInterest:
      return new[] { "OpenInterest" };  // <=

    case SecuritySeedData.OpenInterestTick:
      return new[] { "OpenInterest" };  // <=

    case SecuritySeedData.TradeTick:
      return new[] {"Price", "Volume"};

    ....

    case SecuritySeedData.Fundamentals:
      return new string[0];

    default:
      throw new ArgumentOutOfRangeException(nameof(type), type, null);
  }
}

ILSpy

V3139 Two or more case-branches perform the same actions. ILSpy Images.cs 251

protected override ImageSource GetBaseImage(MemberIcon icon)
{
  ImageSource baseImage;
  switch (icon)
  {
    case MemberIcon.Field:
      baseImage = Images.Field;
      break;
    case MemberIcon.FieldReadOnly:
      baseImage = Images.FieldReadOnly;
      break;
    case MemberIcon.Literal:
      baseImage = Images.Literal;             // <=
      break;
    case MemberIcon.EnumValue:
      baseImage = Images.Literal;             // <=
      break;
    case MemberIcon.Property:
      baseImage = Images.Property;
      break;
    case MemberIcon.Indexer:
      baseImage = Images.Indexer;
      break;
    case MemberIcon.Method:
      baseImage = Images.Method;
      break;
    case MemberIcon.Constructor:
      baseImage = Images.Constructor;
      break;
    case MemberIcon.VirtualMethod:
      baseImage = Images.VirtualMethod;
      break;
    case MemberIcon.Operator:
      baseImage = Images.Operator;
      break;
    case MemberIcon.ExtensionMethod:
      baseImage = Images.ExtensionMethod;
      break;
    case MemberIcon.PInvokeMethod:
      baseImage = Images.PInvokeMethod;
      break;
    case MemberIcon.Event:
      baseImage = Images.Event;
      break;
    default:
      throw new ArgumentOutOfRangeException(nameof(icon),
                 $"MemberIcon.{icon} is not supported!");
  }

  return baseImage;
}

ILSpy

V3139 Two or more case-branches perform the same actions. ICSharpCode.Decompiler CSharpConversions.cs 829

bool ImplicitConstantExpressionConversion(ResolveResult rr, IType toType)
{
  ....
  switch (toTypeCode)
  {
    case TypeCode.SByte:
      return val >= SByte.MinValue && val <= SByte.MaxValue;
    case TypeCode.Byte:
      return val >= Byte.MinValue && val <= Byte.MaxValue;
    case TypeCode.Int16:
      return val >= Int16.MinValue && val <= Int16.MaxValue;
    case TypeCode.UInt16:
      return val >= UInt16.MinValue && val <= UInt16.MaxValue;
    case TypeCode.UInt32:
      return val >= 0;                 // <=
    case TypeCode.UInt64:
      return val >= 0;                 // <=
  }
  ....
}

Similar errors can be found in some other places:

• V3139 Two or more case-branches perform the same actions. ICSharpCode.Decompiler EscapeInvalidIdentifiers.cs 85
• V3139 Two or more case-branches perform the same actions. ICSharpCode.Decompiler TransformExpressionTrees.cs 370