Program: 10304
Project: 10304
Buggy source:
@EventHandler public void serverTag(ReplaceableTagEvent event){
  if (!event.matches("String_Node_Str") || event.replaced())   return;
  Attribute attribute=new Attribute(event.raw_tag,event.getScriptEntry()).fulfill(1);
  if (attribute.startsWith("String_Node_Str")) {
    String flag_name;
    if (attribute.hasContext(1))     flag_name=attribute.getContext(1);
 else {
      event.setReplaced("String_Node_Str");
      return;
    }
    event.setReplaced(new Element(FlagManager.serverHasFlag(flag_name)).getAttribute(attribute.fulfill(1)));
  }
  if (attribute.startsWith("String_Node_Str")) {
    String flag_name;
    if (attribute.hasContext(1))     flag_name=attribute.getContext(1);
 else {
      event.setReplaced("String_Node_Str");
      return;
    }
    attribute.fulfill(1);
    if (attribute.startsWith("String_Node_Str") || attribute.startsWith("String_Node_Str")) {
      event.setReplaced(new Element(!FlagManager.serverHasFlag(flag_name)).getAttribute(attribute.fulfill(1)));
      return;
    }
    if (attribute.startsWith("String_Node_Str") && !FlagManager.serverHasFlag(flag_name)) {
      event.setReplaced(new Element(0).getAttribute(attribute.fulfill(1)));
      return;
    }
    if (FlagManager.serverHasFlag(flag_name))     event.setReplaced(new dList(DenizenAPI.getCurrentInstance().flagManager().getGlobalFlag(flag_name)).getAttribute(attribute));
 else     event.setReplaced("String_Node_Str");
    return;
  }
  if (attribute.startsWith("String_Node_Str")) {
    event.setReplaced(new Element(System.currentTimeMillis()).getAttribute(attribute.fulfill(1)));
  }
  if (attribute.startsWith("String_Node_Str")) {
    NPC npc=((Citizens)Bukkit.getPluginManager().getPlugin("String_Node_Str")).getNPCSelector().getSelected(Bukkit.getConsoleSender());
    if (npc == null)     event.setReplaced(Element.NULL.getAttribute(attribute.fulfill(1)));
 else     event.setReplaced(new dNPC(npc).getAttribute(attribute.fulfill(1)));
    return;
  }
  if (attribute.startsWith("String_Node_Str") && attribute.hasContext(1)) {
    ArrayList<dNPC> npcs=new ArrayList<dNPC>();
    for (    NPC npc : CitizensAPI.getNPCRegistry())     if (npc.getName().equalsIgnoreCase(attribute.getContext(1)))     npcs.add(dNPC.mirrorCitizensNPC(npc));
    event.setReplaced(new dList(npcs).getAttribute(attribute.fulfill(1)));
    return;
  }
  if (attribute.startsWith("String_Node_Str") && attribute.hasContext(1)) {
    event.setReplaced(new Element(new File(DenizenAPI.getCurrentInstance().getDataFolder(),attribute.getContext(1)).exists()).getAttribute(attribute.fulfill(1)));
    return;
  }
  if (attribute.startsWith("String_Node_Str")) {
    event.setReplaced(new Element(DenizenAPI.getCurrentInstance().getDescription().getVersion()).getAttribute(attribute.fulfill(1)));
    return;
  }
  if (attribute.startsWith("String_Node_Str")) {
    event.setReplaced(new Element(Bukkit.getBukkitVersion()).getAttribute(attribute.fulfill(1)));
    return;
  }
  if (attribute.startsWith("String_Node_Str")) {
    event.setReplaced(new Element(Bukkit.getServer().getVersion()).getAttribute(attribute.fulfill(1)));
    return;
  }
  if (attribute.startsWith("String_Node_Str")) {
    dList plugins=new dList();
    for (    Plugin plugin : Bukkit.getServer().getPluginManager().getPlugins())     plugins.add(plugin.getName());
    event.setReplaced(plugins.getAttribute(attribute.fulfill(1)));
    return;
  }
  if (attribute.startsWith("String_Node_Str") && attribute.hasContext(1)) {
    Player matchPlayer=null;
    String matchInput=attribute.getContext(1).toLowerCase();
    for (    Player player : Bukkit.getOnlinePlayers()) {
      if (player.getName().toLowerCase().equals(matchInput)) {
        matchPlayer=player;
        break;
      }
 else       if (player.getName().toLowerCase().contains(matchInput) && matchPlayer == null) {
        matchPlayer=player;
      }
    }
    if (matchPlayer == null) {
      event.setReplaced("String_Node_Str");
    }
 else {
      event.setReplaced(new dPlayer(matchPlayer).getAttribute(attribute.fulfill(1)));
    }
    return;
  }
  if (attribute.startsWith("String_Node_Str") && attribute.hasContext(1)) {
    dScript script=dScript.valueOf(attribute.getContext(1));
    if (script == null || !(script.getContainer() instanceof AssignmentScriptContainer)) {
      dB.echoError("String_Node_Str");
    }
 else {
      ArrayList<dNPC> npcs=new ArrayList<dNPC>();
      for (      NPC npc : CitizensAPI.getNPCRegistry()) {
        if (npc.hasTrait(AssignmentTrait.class) && npc.getTrait(AssignmentTrait.class).hasAssignment() && npc.getTrait(AssignmentTrait.class).getAssignment().getName().equalsIgnoreCase(script.getName()))         npcs.add(dNPC.mirrorCitizensNPC(npc));
      }
      event.setReplaced(new dList(npcs).getAttribute(attribute.fulfill(1)));
      return;
    }
  }
  if (attribute.startsWith("String_Node_Str")) {
    ArrayList<dNPC> npcs=new ArrayList<dNPC>();
    for (    NPC npc : CitizensAPI.getNPCRegistry())     npcs.add(dNPC.mirrorCitizensNPC(npc));
    event.setReplaced(new dList(npcs).getAttribute(attribute.fulfill(1)));
    return;
  }
  if (attribute.startsWith("String_Node_Str")) {
    ArrayList<dWorld> worlds=new ArrayList<dWorld>();
    for (    World world : Bukkit.getWorlds())     worlds.add(dWorld.mirrorBukkitWorld(world));
    event.setReplaced(new dList(worlds).getAttribute(attribute.fulfill(1)));
    return;
  }
  if (attribute.startsWith("String_Node_Str")) {
    ArrayList<dPlayer> players=new ArrayList<dPlayer>();
    for (    Player player : Bukkit.getOnlinePlayers())     players.add(dPlayer.mirrorBukkitPlayer(player));
    for (    OfflinePlayer player : dPlayer.offlinePlayers)     players.add(dPlayer.mirrorBukkitPlayer(player));
    event.setReplaced(new dList(players).getAttribute(attribute.fulfill(1)));
    return;
  }
  if (attribute.startsWith("String_Node_Str")) {
    ArrayList<dPlugin> plugins=new ArrayList<dPlugin>();
    for (    Plugin plugin : Bukkit.getServer().getPluginManager().getPlugins())     plugins.add(new dPlugin(plugin));
    event.setReplaced(new dList(plugins).getAttribute(attribute.fulfill(1)));
    return;
  }
  if (attribute.startsWith("String_Node_Str")) {
    ArrayList<dPlayer> players=new ArrayList<dPlayer>();
    for (    Player player : Bukkit.getOnlinePlayers())     players.add(dPlayer.mirrorBukkitPlayer(player));
    event.setReplaced(new dList(players).getAttribute(attribute.fulfill(1)));
    return;
  }
  if (attribute.startsWith("String_Node_Str")) {
    ArrayList<dPlayer> players=new ArrayList<dPlayer>();
    for (    OfflinePlayer player : dPlayer.offlinePlayers)     players.add(dPlayer.mirrorBukkitPlayer(player));
    event.setReplaced(new dList(players).getAttribute(attribute.fulfill(1)));
    return;
  }
  if (attribute.startsWith("String_Node_Str")) {
    ArrayList<dPlayer> players=new ArrayList<dPlayer>();
    for (    Player player : Bukkit.getOnlinePlayers())     if (player.isOp())     players.add(dPlayer.mirrorBukkitPlayer(player));
    for (    OfflinePlayer player : dPlayer.offlinePlayers)     if (player.isOp())     players.add(dPlayer.mirrorBukkitPlayer(player));
    event.setReplaced(new dList(players).getAttribute(attribute.fulfill(1)));
    return;
  }
  if (attribute.startsWith("String_Node_Str")) {
    ArrayList<dPlayer> players=new ArrayList<dPlayer>();
    for (    Player player : Bukkit.getOnlinePlayers())     if (player.isOp())     players.add(dPlayer.mirrorBukkitPlayer(player));
    event.setReplaced(new dList(players).getAttribute(attribute.fulfill(1)));
    return;
  }
  if (attribute.startsWith("String_Node_Str")) {
    ArrayList<dPlayer> players=new ArrayList<dPlayer>();
    for (    OfflinePlayer player : dPlayer.offlinePlayers)     if (player.isOp())     players.add(dPlayer.mirrorBukkitPlayer(player));
    event.setReplaced(new dList(players).getAttribute(attribute.fulfill(1)));
    return;
  }
  if (attribute.startsWith("String_Node_Str")) {
    event.setReplaced(new Element(Bukkit.getServer().getMotd()).getAttribute(attribute.fulfill(1)));
    return;
  }
}

Fixed version (ground truth):
@EventHandler public void serverTag(ReplaceableTagEvent event){
  if (!event.matches("String_Node_Str") || event.replaced())   return;
  Attribute attribute=new Attribute(event.raw_tag,event.getScriptEntry()).fulfill(1);
  if (attribute.startsWith("String_Node_Str")) {
    String flag_name;
    if (attribute.hasContext(1))     flag_name=attribute.getContext(1);
 else {
      event.setReplaced("String_Node_Str");
      return;
    }
    event.setReplaced(new Element(FlagManager.serverHasFlag(flag_name)).getAttribute(attribute.fulfill(1)));
  }
  if (attribute.startsWith("String_Node_Str")) {
    String flag_name;
    if (attribute.hasContext(1))     flag_name=attribute.getContext(1);
 else {
      event.setReplaced("String_Node_Str");
      return;
    }
    attribute.fulfill(1);
    if (attribute.startsWith("String_Node_Str") || attribute.startsWith("String_Node_Str")) {
      event.setReplaced(new Element(!FlagManager.serverHasFlag(flag_name)).getAttribute(attribute.fulfill(1)));
      return;
    }
    if (attribute.startsWith("String_Node_Str") && !FlagManager.serverHasFlag(flag_name)) {
      event.setReplaced(new Element(0).getAttribute(attribute.fulfill(1)));
      return;
    }
    if (FlagManager.serverHasFlag(flag_name))     event.setReplaced(new dList(DenizenAPI.getCurrentInstance().flagManager().getGlobalFlag(flag_name)).getAttribute(attribute));
 else     event.setReplaced("String_Node_Str");
    return;
  }
  if (attribute.startsWith("String_Node_Str")) {
    event.setReplaced(new Element(System.currentTimeMillis()).getAttribute(attribute.fulfill(1)));
  }
  if (attribute.startsWith("String_Node_Str")) {
    NPC npc=((Citizens)Bukkit.getPluginManager().getPlugin("String_Node_Str")).getNPCSelector().getSelected(Bukkit.getConsoleSender());
    if (npc == null)     event.setReplaced(Element.NULL.getAttribute(attribute.fulfill(1)));
 else     event.setReplaced(new dNPC(npc).getAttribute(attribute.fulfill(1)));
    return;
  }
  if (attribute.startsWith("String_Node_Str") && attribute.hasContext(1)) {
    ArrayList<dNPC> npcs=new ArrayList<dNPC>();
    for (    NPC npc : CitizensAPI.getNPCRegistry())     if (npc.getName().equalsIgnoreCase(attribute.getContext(1)))     npcs.add(dNPC.mirrorCitizensNPC(npc));
    event.setReplaced(new dList(npcs).getAttribute(attribute.fulfill(1)));
    return;
  }
  if (attribute.startsWith("String_Node_Str") && attribute.hasContext(1)) {
    event.setReplaced(new Element(new File(DenizenAPI.getCurrentInstance().getDataFolder(),attribute.getContext(1)).exists()).getAttribute(attribute.fulfill(1)));
    return;
  }
  if (attribute.startsWith("String_Node_Str")) {
    event.setReplaced(new Element(DenizenAPI.getCurrentInstance().getDescription().getVersion()).getAttribute(attribute.fulfill(1)));
    return;
  }
  if (attribute.startsWith("String_Node_Str")) {
    event.setReplaced(new Element(Bukkit.getBukkitVersion()).getAttribute(attribute.fulfill(1)));
    return;
  }
  if (attribute.startsWith("String_Node_Str")) {
    event.setReplaced(new Element(Bukkit.getServer().getVersion()).getAttribute(attribute.fulfill(1)));
    return;
  }
  if (attribute.startsWith("String_Node_Str")) {
    dList plugins=new dList();
    for (    Plugin plugin : Bukkit.getServer().getPluginManager().getPlugins())     plugins.add(plugin.getName());
    event.setReplaced(plugins.getAttribute(attribute.fulfill(1)));
    return;
  }
  if (attribute.startsWith("String_Node_Str") && attribute.hasContext(1)) {
    Player matchPlayer=null;
    String matchInput=attribute.getContext(1).toLowerCase();
    for (    Player player : Bukkit.getOnlinePlayers()) {
      if (player.getName().toLowerCase().equals(matchInput)) {
        matchPlayer=player;
        break;
      }
 else       if (player.getName().toLowerCase().contains(matchInput) && matchPlayer == null) {
        matchPlayer=player;
      }
    }
    if (matchPlayer == null) {
      event.setReplaced("String_Node_Str");
    }
 else {
      event.setReplaced(new dPlayer(matchPlayer).getAttribute(attribute.fulfill(1)));
    }
    return;
  }
  if (attribute.startsWith("String_Node_Str") && attribute.hasContext(1)) {
    dScript script=dScript.valueOf(attribute.getContext(1));
    if (script == null || !(script.getContainer() instanceof AssignmentScriptContainer)) {
      dB.echoError("String_Node_Str");
    }
 else {
      ArrayList<dNPC> npcs=new ArrayList<dNPC>();
      for (      NPC npc : CitizensAPI.getNPCRegistry()) {
        if (npc.hasTrait(AssignmentTrait.class) && npc.getTrait(AssignmentTrait.class).hasAssignment() && npc.getTrait(AssignmentTrait.class).getAssignment().getName().equalsIgnoreCase(script.getName()))         npcs.add(dNPC.mirrorCitizensNPC(npc));
      }
      event.setReplaced(new dList(npcs).getAttribute(attribute.fulfill(1)));
      return;
    }
  }
  if (attribute.startsWith("String_Node_Str")) {
    ArrayList<dNPC> npcs=new ArrayList<dNPC>();
    for (    NPC npc : CitizensAPI.getNPCRegistry())     npcs.add(dNPC.mirrorCitizensNPC(npc));
    event.setReplaced(new dList(npcs).getAttribute(attribute.fulfill(1)));
    return;
  }
  if (attribute.startsWith("String_Node_Str")) {
    ArrayList<dWorld> worlds=new ArrayList<dWorld>();
    for (    World world : Bukkit.getWorlds())     worlds.add(dWorld.mirrorBukkitWorld(world));
    event.setReplaced(new dList(worlds).getAttribute(attribute.fulfill(1)));
    return;
  }
  if (attribute.startsWith("String_Node_Str")) {
    ArrayList<dPlugin> plugins=new ArrayList<dPlugin>();
    for (    Plugin plugin : Bukkit.getServer().getPluginManager().getPlugins())     plugins.add(new dPlugin(plugin));
    event.setReplaced(new dList(plugins).getAttribute(attribute.fulfill(1)));
    return;
  }
  if (attribute.startsWith("String_Node_Str")) {
    ArrayList<dPlayer> players=new ArrayList<dPlayer>();
    for (    OfflinePlayer player : dPlayer.offlinePlayers)     players.add(dPlayer.mirrorBukkitPlayer(player));
    event.setReplaced(new dList(players).getAttribute(attribute.fulfill(1)));
    return;
  }
  if (attribute.startsWith("String_Node_Str")) {
    ArrayList<dPlayer> players=new ArrayList<dPlayer>();
    for (    Player player : Bukkit.getOnlinePlayers())     players.add(dPlayer.mirrorBukkitPlayer(player));
    event.setReplaced(new dList(players).getAttribute(attribute.fulfill(1)));
    return;
  }
  if (attribute.startsWith("String_Node_Str")) {
    ArrayList<dPlayer> players=new ArrayList<dPlayer>();
    for (    OfflinePlayer player : dPlayer.offlinePlayers)     if (!player.isOnline())     players.add(dPlayer.mirrorBukkitPlayer(player));
    event.setReplaced(new dList(players).getAttribute(attribute.fulfill(1)));
    return;
  }
  if (attribute.startsWith("String_Node_Str")) {
    ArrayList<dPlayer> players=new ArrayList<dPlayer>();
    for (    OfflinePlayer player : dPlayer.offlinePlayers)     if (player.isOp())     players.add(dPlayer.mirrorBukkitPlayer(player));
    event.setReplaced(new dList(players).getAttribute(attribute.fulfill(1)));
    return;
  }
  if (attribute.startsWith("String_Node_Str")) {
    ArrayList<dPlayer> players=new ArrayList<dPlayer>();
    for (    Player player : Bukkit.getOnlinePlayers())     if (player.isOp())     players.add(dPlayer.mirrorBukkitPlayer(player));
    event.setReplaced(new dList(players).getAttribute(attribute.fulfill(1)));
    return;
  }
  if (attribute.startsWith("String_Node_Str")) {
    ArrayList<dPlayer> players=new ArrayList<dPlayer>();
    for (    OfflinePlayer player : dPlayer.offlinePlayers)     if (player.isOp() && !player.isOnline())     players.add(dPlayer.mirrorBukkitPlayer(player));
    event.setReplaced(new dList(players).getAttribute(attribute.fulfill(1)));
    return;
  }
  if (attribute.startsWith("String_Node_Str")) {
    event.setReplaced(new Element(Bukkit.getServer().getMotd()).getAttribute(attribute.fulfill(1)));
    return;
  }
}