[tools] Separate changing to contest directory and getting problems list

bin/config.py

@@ -125,14 +125,18 @@
 # fmt: on
 
 
-def set_default_args() -> None:
+def set_default_args() -> list[str]:
     # Set default argument values.
+    missing = []
     for arg in ARGS_LIST:
         if not hasattr(args, arg):
             setattr(args, arg, None)
+            missing.append(arg)
     for arg, value in DEFAULT_ARGS.items():
         if not hasattr(args, arg):
             setattr(args, arg, value)
+            missing.append(arg)
+    return missing
 
 
 level: Optional[Literal["problem", "problemset"]] = None

bin/contest.py

@@ -38,6 +38,11 @@ def problems_yaml() -> Optional[list[dict[str, Any]]]:
         _problems_yaml = False
         return None
     _problems_yaml = read_yaml(problemsyaml_path)
+    if _problems_yaml is None:
+        _problems_yaml = False
+        return None
+    if not isinstance(_problems_yaml, list):
+        fatal("problems.yaml must contain a list of problems")
     return cast(list[dict[str, Any]], _problems_yaml)
 
 

bin/stats.py

@@ -380,7 +380,7 @@ def get_submissions_row(
         values = []
         for problem in problems:
             directory = (
-                Path().cwd() / "submissions" / problem.name
+                Path.cwd() / "submissions" / problem.name
                 if team_submissions
                 else problem.path / "submissions"
             )