When language is not selected, guess it from the set of enabled languages

cms/grading/languagemanager.py

@@ -50,7 +50,7 @@ def get_language(name: str) -> Language:
     return _BY_NAME[name]
 
 
-def filename_to_language(filename: str) -> Language | None:
+def filename_to_language(filename: str, available_languages: list[Language] | None=None) -> Language | None:
     """Return one of the languages inferred from the given filename.
 
     filename: the file to test.
@@ -59,12 +59,14 @@ def filename_to_language(filename: str) -> Language | None:
     matching the given filename, or None if none match.
 
     """
+    if available_languages is None:
+        available_languages = LANGUAGES
     ext_index = filename.rfind(".")
     if ext_index == -1:
         return None
     ext = filename[ext_index:]
     names = sorted(language.name
-                   for language in LANGUAGES
+                   for language in available_languages
                    if ext in language.source_extensions)
     return None if len(names) == 0 else get_language(names[0])
 

cmscontrib/AddSubmission.py

@@ -46,7 +46,7 @@ def maybe_send_notification(submission_id: int):
     rs.disconnect()
 
 
-def language_from_submitted_files(files: dict[str, str]) -> Language | None:
+def language_from_submitted_files(files: dict[str, str], contest_languages: list[Language]) -> Language | None:
     """Return the language inferred from the submitted files.
 
     files: dictionary mapping the expected filename to a path in
@@ -61,7 +61,7 @@ def language_from_submitted_files(files: dict[str, str]) -> Language | None:
     # TODO: deduplicate with the code in SubmitHandler.
     language = None
     for filename in files.keys():
-        this_language = filename_to_language(files[filename])
+        this_language = filename_to_language(files[filename], contest_languages)
         if this_language is None and ".%l" in filename:
             raise ValueError(
                 "Cannot recognize language for file `%s'." % filename)
@@ -126,7 +126,11 @@ def add_submission(
                 if given_language is not None:
                     language = get_language(given_language)
                 else:
-                    language = language_from_submitted_files(files)
+                    contest_languages = [
+                        get_language(language) 
+                        for language in task.contest.languages
+                    ]
+                    language = language_from_submitted_files(files, contest_languages)
             except ValueError as e:
                 logger.critical(e)
                 return False