Program: 170289
Project: 170289
Buggy source:
@Override public void dialogResult(AbstractGuiDialog dialog,DialogResult result){
  if (result == DialogResult.OK) {
    if (dialog instanceof GuiDialogNewFolder) {
      GuiDialogNewFolder newFolderDialog=(GuiDialogNewFolder)dialog;
      if (fileSwitchType == LibraryFileType.LOCAL) {
        File dir=new File(SkinIOUtils.getSkinLibraryDirectory(),currentFolder);
        dir=new File(dir,newFolderDialog.getFolderName());
        if (!dir.exists()) {
          dir.mkdir();
        }
        reloadLocalLibrary();
        ModLogger.log(String.format("String_Node_Str",newFolderDialog.getFolderName(),currentFolder));
        ModLogger.log("String_Node_Str" + dir.getAbsolutePath());
      }
 else {
      }
    }
    if (dialog instanceof GuiDialogDelete) {
      GuiDialogDelete deleteDialog=(GuiDialogDelete)dialog;
      if (fileSwitchType == LibraryFileType.LOCAL) {
        boolean isFolder=deleteDialog.isFolder();
        String name=deleteDialog.getName();
        File dir=new File(SkinIOUtils.getSkinLibraryDirectory(),currentFolder);
        if (deleteDialog.isFolder()) {
          dir=new File(dir,name + "String_Node_Str");
        }
 else {
          dir=new File(dir,name + SkinIOUtils.SKIN_FILE_EXTENSION);
        }
        if (dir.isDirectory() == isFolder) {
          ModLogger.log("String_Node_Str" + dir.getAbsolutePath());
          if (dir.exists()) {
            ModLogger.log("String_Node_Str" + dir.getAbsolutePath());
            try {
              FileUtils.deleteDirectory(dir);
              reloadLocalLibrary();
            }
 catch (            IOException e) {
              e.printStackTrace();
            }
          }
        }
      }
 else {
      }
    }
    if (dialog instanceof GuiDialogOverwrite) {
      GuiDialogOverwrite overwriteDialog=(GuiDialogOverwrite)dialog;
      MessageClientGuiLoadSaveArmour message;
      boolean clientLoad=false;
      boolean publicList=true;
      if (fileSwitchType == LibraryFileType.LOCAL && !mc.isIntegratedServerRunning()) {
        clientLoad=true;
      }
      if (fileSwitchType == LibraryFileType.SERVER_PRIVATE) {
        publicList=false;
      }
      if (clientLoad) {
        message=new MessageClientGuiLoadSaveArmour(overwriteDialog.getFileName(),currentFolder,LibraryPacketType.CLIENT_SAVE,false);
        PacketHandler.networkWrapper.sendToServer(message);
      }
 else {
        message=new MessageClientGuiLoadSaveArmour(overwriteDialog.getFileName(),currentFolder,LibraryPacketType.SERVER_SAVE,publicList);
        PacketHandler.networkWrapper.sendToServer(message);
      }
    }
  }
  super.dialogResult(dialog,result);
}

Fixed version (ground truth):
@Override public void dialogResult(AbstractGuiDialog dialog,DialogResult result){
  if (result == DialogResult.OK) {
    if (dialog instanceof GuiDialogNewFolder) {
      GuiDialogNewFolder newFolderDialog=(GuiDialogNewFolder)dialog;
      if (fileSwitchType == LibraryFileType.LOCAL) {
        File dir=new File(SkinIOUtils.getSkinLibraryDirectory(),currentFolder);
        dir=new File(dir,newFolderDialog.getFolderName());
        if (!dir.exists()) {
          dir.mkdir();
        }
        reloadLocalLibrary();
        ModLogger.log(String.format("String_Node_Str",newFolderDialog.getFolderName(),currentFolder));
        ModLogger.log("String_Node_Str" + dir.getAbsolutePath());
      }
 else {
      }
    }
    if (dialog instanceof GuiDialogDelete) {
      GuiDialogDelete deleteDialog=(GuiDialogDelete)dialog;
      if (fileSwitchType == LibraryFileType.LOCAL) {
        boolean isFolder=deleteDialog.isFolder();
        String name=deleteDialog.getName();
        File dir=new File(SkinIOUtils.getSkinLibraryDirectory(),currentFolder);
        if (deleteDialog.isFolder()) {
          dir=new File(dir,name + "String_Node_Str");
        }
 else {
          dir=new File(dir,name + SkinIOUtils.SKIN_FILE_EXTENSION);
        }
        if (dir.isDirectory() == isFolder) {
          if (dir.exists()) {
            if (isFolder) {
              try {
                FileUtils.deleteDirectory(dir);
                reloadLocalLibrary();
              }
 catch (              IOException e) {
                e.printStackTrace();
              }
            }
 else {
              ClientSkinCache.INSTANCE.clearIdForFileName(currentFolder + deleteDialog.getName());
              dir.delete();
              reloadLocalLibrary();
            }
          }
        }
      }
 else {
      }
    }
    if (dialog instanceof GuiDialogOverwrite) {
      GuiDialogOverwrite overwriteDialog=(GuiDialogOverwrite)dialog;
      MessageClientGuiLoadSaveArmour message;
      boolean clientLoad=false;
      boolean publicList=true;
      if (fileSwitchType == LibraryFileType.LOCAL && !mc.isIntegratedServerRunning()) {
        clientLoad=true;
      }
      if (fileSwitchType == LibraryFileType.SERVER_PRIVATE) {
        publicList=false;
      }
      if (clientLoad) {
        message=new MessageClientGuiLoadSaveArmour(overwriteDialog.getFileName(),currentFolder,LibraryPacketType.CLIENT_SAVE,false);
        PacketHandler.networkWrapper.sendToServer(message);
      }
 else {
        message=new MessageClientGuiLoadSaveArmour(overwriteDialog.getFileName(),currentFolder,LibraryPacketType.SERVER_SAVE,publicList);
        PacketHandler.networkWrapper.sendToServer(message);
      }
      ClientSkinCache.INSTANCE.clearIdForFileName(currentFolder + overwriteDialog.getFileName());
    }
  }
  super.dialogResult(dialog,result);
}