fix future problem of 999 index

flit.py

@@ -123,7 +123,7 @@ def parse_opts():
         type=str,
         help="List only named share",
         default=None,
-        nargs="?"
+        nargs="?",
     )
 
     del_parser = subparsers.add_parser("del", add_help=False)
@@ -157,13 +157,16 @@ def random_name():
     """
     while True:
         existing_names = [c["name"] for c in get_folders()]
-        index = 0
-        for existing in existing_names:
-            try:
-                e_index = int(existing[0:3])
-                index = max(e_index + 1, index)
-            except:
-                pass
+        existing_numbers = [
+            tryint(num[0:3]) for num in existing_names if tryint(num[0:3]) != None
+        ]
+
+        index = max(existing_numbers) + 1
+        if index > 999:
+            for index in range(1000):
+                if not index in existing_numbers:
+                    break
+
         name = "{:03d}-{}-{}".format(
             index,
             "".join([random_char() for x in range(3)]),
@@ -382,6 +385,22 @@ def write_config(p, config):
         return json.dump(config, fp, indent=2, sort_keys=True)
 
 
+def tryint(s):
+    """Return integer, or None
+
+    Args:
+        s (str): Integer as string
+
+    Returns:
+        Int or None
+    """
+
+    try:
+        return int(s, 10)
+    except Exception:
+        return None
+
+
 if __name__ == "__main__":
     opts = parse_opts()
     cwd = os.getcwd()