added some path error checking

.gitignore

@@ -1,3 +1,4 @@
 lichess_elite_db/
 *.pyc
 stockfish_20090216_x64_avx2.exe
+stockfish_20090216_x64_bmi2.exe

src/config.py

@@ -7,8 +7,8 @@
 
 # points to the location of the .pgn files from the lichess elite db from a reddit user
 # found at https://www.reddit.com/r/chess/comments/gz8acg/introducing_the_lichess_elite_database/
-LICHESS_DB = Path(r"E:\paper_repos\tj-chess\lichess_elite_db")
+LICHESS_DB = Path(r"D:/")
 
-STOCKFISH_ENGINE_PATH = Path(r"E:\paper_repos\tj-chess\stockfish_20090216_x64_avx2.exe")
+STOCKFISH_ENGINE_PATH = Path(r"D:\paper_repos\tj-chess\stockfish_20090216_x64_bmi2.exe")
 
 # **********  ********** #

src/gui/pyqt_classes.py

@@ -13,6 +13,8 @@
 class chessMainWindow(QMainWindow):
     def __init__(self):
         super().__init__()
+        if not cfg.LICHESS_DB.exists() or not cfg.LICHESS_DB.exists():
+            raise ValueError("The paths in config.py need to be configured for your system.")
         self.title = 'Chess Viewer and Player'
         self.left = 0
         self.top = 0
@@ -52,7 +54,7 @@ def viewer_open_file_btn_click(self):
         fname = Path(str(fname[0]))
         self.viewer_pgn_file_txt.setText(str(fname))
 
-        if Path(self.viewer_pgn_file_txt.text()).exists:
+        if Path(self.viewer_pgn_file_txt.text()).exists() and Path(self.viewer_pgn_file_txt.text()).suffix == '.pgn':
             # open game file
             pgn_file = open(Path(self.viewer_pgn_file_txt.text()))
             self.viewer_games = []