Add unittest template

1 files changed, 81 insertions, 0 deletions

diff --git a/resources/unittest_template.py b/resources/unittest_template.py
new file mode 100644
index 0000000..7e21b97
--- /dev/null
+++ b/resources/unittest_template.py
@@ -0,0 +1,81 @@
+import ast
+import io
+import os
+import sys
+import traceback
+import unittest
+from itertools import chain
+from types import ModuleType, SimpleNamespace
+from typing import NoReturn
+from unittest import mock
+
+### USER CODE
+
+
+class RunnerTestCase(unittest.TestCase):
+### UNIT CODE
+
+
+# Fake file object not writing anything
+DEVNULL = SimpleNamespace(write=lambda *_: None, flush=lambda *_: None)
+
+RESULT = io.StringIO()
+ORIGINAL_STDOUT = sys.stdout
+
+sys.stdout = DEVNULL
+sys.stderr = DEVNULL
+
+
+def _exit_sandbox(code: int) -> NoReturn:
+    """
+    Codes:
+    - 0: Executed with success
+    - 5: Syntax error while parsing user code
+    - 99: Internal error
+    """
+    result_content = RESULT.getvalue()
+
+    print(
+        f"{result_content}",
+        file=ORIGINAL_STDOUT
+    )
+    sys.exit(code)
+
+
+def _load_user_module() -> ModuleType:
+    try:
+        ast.parse(USER_CODE, "<input>")
+    except SyntaxError:
+        RESULT.write("".join(traceback.format_exception(*sys.exc_info(), limit=0)))
+        _exit_sandbox(5)
+
+    _module = ModuleType("module")
+    exec(USER_CODE, _module.__dict__)
+
+    return _module
+
+
+def _main() -> None:
+    suite = unittest.defaultTestLoader.loadTestsFromTestCase(RunnerTestCase)
+    result = suite.run(unittest.TestResult())
+
+    RESULT.write(str(int(result.wasSuccessful())))
+
+    if not result.wasSuccessful():
+        RESULT.write(
+            ";".join(chain(
+                (error[0]._testMethodName.lstrip("test_") for error in result.errors),
+                (failure[0]._testMethodName.lstrip("test_") for failure in result.failures)
+            ))
+        )
+
+    _exit_sandbox(0)
+
+
+try:
+    module = _load_user_module()
+    _main()
+except Exception:
+    print("Uncaught exception:\n", file=RESULT)
+    traceback.print_exc(file=RESULT)
+    _exit_sandbox(99)