Program: 4117
Project: 4117
Buggy source:
public static void visitControllerActions(@NotNull final Project project,@NotNull ControllerActionVisitor visitor,@Nullable String prefix){
  Collection<PhpClass> allSubclasses=new HashSet<PhpClass>(){
{
      addAll(PhpIndex.getInstance(project).getAllSubclasses("String_Node_Str"));
      addAll(PhpIndex.getInstance(project).getAllSubclasses("String_Node_Str"));
    }
  }
;
  String ns=prefix;
  boolean prioritised=false;
  if (prefix == null) {
    ns=getDefaultNamespace(project);
    prioritised=true;
  }
  for (  PhpClass phpClass : allSubclasses) {
    if (!phpClass.isAbstract()) {
      for (      Method method : phpClass.getMethods()) {
        String className=phpClass.getPresentableFQN();
        if (className != null) {
          String methodName=method.getName();
          if (!method.isStatic() && method.getAccess().isPublic() && !methodName.startsWith("String_Node_Str")) {
            PhpClass phpTrait=method.getContainingClass();
            if (phpTrait == null || !("String_Node_Str".equals(phpTrait.getName()) || "String_Node_Str".equals(phpTrait.getName()) || "String_Node_Str".equals(phpTrait.getName()))) {
              if (className.startsWith(ns + "String_Node_Str")) {
                className=className.substring(ns.length() + 1);
              }
              if (StringUtils.isNotBlank(className)) {
                visitor.visit(method,className + "String_Node_Str" + methodName,prioritised);
              }
            }
          }
        }
      }
    }
  }
}

Fixed version (ground truth):
public static void visitControllerActions(@NotNull final Project project,@NotNull ControllerActionVisitor visitor,@Nullable String prefix){
  Collection<PhpClass> allSubclasses=new HashSet<PhpClass>(){
{
      addAll(PhpIndex.getInstance(project).getAllSubclasses("String_Node_Str"));
      addAll(PhpIndex.getInstance(project).getAllSubclasses("String_Node_Str"));
    }
  }
;
  String ns=getDefaultNamespace(project) + "String_Node_Str";
  String prefixedNs=ns + (prefix != null && !prefix.equals("String_Node_Str") ? prefix + "String_Node_Str" : "String_Node_Str");
  for (  PhpClass phpClass : allSubclasses) {
    if (!phpClass.isAbstract()) {
      for (      Method method : phpClass.getMethods()) {
        String className=phpClass.getPresentableFQN();
        String methodName=method.getName();
        if (!method.isStatic() && method.getAccess().isPublic() && !methodName.startsWith("String_Node_Str")) {
          PhpClass phpTrait=method.getContainingClass();
          if (phpTrait == null || !("String_Node_Str".equals(phpTrait.getName()) || "String_Node_Str".equals(phpTrait.getName()) || "String_Node_Str".equals(phpTrait.getName()))) {
            boolean prioritised=false;
            if (prefix != null && className.startsWith(prefixedNs)) {
              className=className.substring(prefixedNs.length());
              prioritised=true;
            }
 else             if (className.startsWith(ns)) {
              className=className.substring(ns.length());
            }
            if (StringUtils.isNotBlank(className)) {
              visitor.visit(method,className + "String_Node_Str" + methodName,prioritised);
            }
          }
        }
      }
    }
  }
}