Program: 130539
Project: 130539
Buggy source:
@Nullable public static HighlightInfo highlightNamed(@NotNull HighlightInfoHolder holder,@Nullable PsiElement element,@Nullable PsiElement target){
  if (target == null) {
    return null;
  }
  IElementType elementType=target.getNode().getElementType();
  if (CSharpTokenSets.KEYWORDS.contains(elementType)) {
    return null;
  }
  TextAttributesKey key=null;
  if (element instanceof CSharpTypeDeclaration) {
    if (DotNetInheritUtil.isParent(DotNetTypes.System_Attribute,(DotNetTypeDeclaration)element,true)) {
      key=CSharpHighlightKey.ATTRIBUTE_NAME;
    }
 else {
      key=CSharpHighlightKey.CLASS_NAME;
    }
  }
 else   if (element instanceof DotNetConstructorDeclaration) {
    PsiElement parent=element.getParent();
    highlightNamed(holder,parent,target);
    return null;
  }
 else   if (element instanceof DotNetGenericParameter || element instanceof CSharpTypeDefStatementImpl) {
    key=CSharpHighlightKey.GENERIC_PARAMETER_NAME;
  }
 else   if (element instanceof DotNetParameter || element instanceof CSharpLambdaParameter) {
    key=CSharpHighlightKey.PARAMETER;
  }
 else   if (element instanceof DotNetMethodDeclaration) {
    if (CSharpMethodImplUtil.isExtensionWrapper(element)) {
      key=CSharpHighlightKey.EXTENSION_METHOD;
    }
 else {
      key=((DotNetModifierListOwner)element).hasModifier(CSharpModifier.STATIC) ? CSharpHighlightKey.STATIC_METHOD : CSharpHighlightKey.INSTANCE_METHOD;
    }
  }
 else   if (element instanceof CSharpMacroDefine) {
    key=CSharpHighlightKey.MACRO_VARIABLE;
  }
 else   if (element instanceof CSharpLocalVariable) {
    key=DefaultLanguageHighlighterColors.LOCAL_VARIABLE;
  }
 else   if (element instanceof DotNetVariable) {
    key=((DotNetVariable)element).hasModifier(CSharpModifier.STATIC) ? CSharpHighlightKey.STATIC_FIELD : CSharpHighlightKey.INSTANCE_FIELD;
  }
 else {
    return null;
  }
  HighlightInfo info=HighlightInfo.newHighlightInfo(HighlightInfoType.INFORMATION).range(target).textAttributes(key).create();
  holder.add(info);
  if (element instanceof DotNetModifierListOwner && DotNetAttributeUtil.hasAttribute((DotNetModifierListOwner)element,DotNetTypes.System_ObsoleteAttribute)) {
    holder.add(HighlightInfo.newHighlightInfo(HighlightInfoType.INFORMATION).range(target).textAttributes(CodeInsightColors.DEPRECATED_ATTRIBUTES).create());
  }
  if (CSharpHighlightUtil.isGeneratedElement(element)) {
    holder.add(HighlightInfo.newHighlightInfo(HighlightInfoType.INFORMATION).range(target).textAttributes(EditorColors.INJECTED_LANGUAGE_FRAGMENT).create());
  }
  return info;
}

Fixed version (ground truth):
@Nullable public static HighlightInfo highlightNamed(@NotNull HighlightInfoHolder holder,@Nullable PsiElement element,@Nullable PsiElement target){
  if (target == null || element == null) {
    return null;
  }
  IElementType elementType=target.getNode().getElementType();
  if (CSharpTokenSets.KEYWORDS.contains(elementType)) {
    return null;
  }
  TextAttributesKey defaultTextAttributeKey=getDefaultTextAttributeKey(element);
  if (defaultTextAttributeKey == null) {
    return null;
  }
  HighlightInfo info=HighlightInfo.newHighlightInfo(HighlightInfoType.INFORMATION).range(target).textAttributes(defaultTextAttributeKey).create();
  holder.add(info);
  if (element instanceof DotNetModifierListOwner && DotNetAttributeUtil.hasAttribute((DotNetModifierListOwner)element,DotNetTypes.System_ObsoleteAttribute)) {
    holder.add(HighlightInfo.newHighlightInfo(HighlightInfoType.INFORMATION).range(target).textAttributes(CodeInsightColors.DEPRECATED_ATTRIBUTES).create());
  }
  if (CSharpHighlightUtil.isGeneratedElement(element)) {
    holder.add(HighlightInfo.newHighlightInfo(HighlightInfoType.INFORMATION).range(target).textAttributes(EditorColors.INJECTED_LANGUAGE_FRAGMENT).create());
  }
  return info;
}