private PsiFileSystemItem @Nullable [] psiFilesFromVirtualFiles(@Nullable List<? extends VirtualFile> fileList) {
    if (fileList == null) return null;
    List<PsiFileSystemItem> sourceFiles = new ArrayList<>();
    for (VirtualFile vFile : fileList) {
      PsiFileSystemItem psiFile = PsiUtilCore.findFileSystemItem(myProject, vFile);
      if (psiFile != null) {
        sourceFiles.add(psiFile);
      }
    }
    return sourceFiles.toArray(new PsiFileSystemItem[0]);
  }
private PsiFileSystemItem @Nullable [] psiFilesFromVirtualFiles(@Nullable List<? extends VirtualFile> fileList)