Assert that testcases are not empty (#20453)
I've seen new contributors make this mistake, though I can't find a PR
as an example.
diff --git a/mypy/test/data.py b/mypy/test/data.py
index 726076e..30e4ef9 100644
--- a/mypy/test/data.py
+++ b/mypy/test/data.py
@@ -314,6 +314,19 @@
# TODO: add a better error message for when someone uses skip and xfail at the same time
elif self.xfail:
self.add_marker(pytest.mark.xfail)
+
+ if (
+ not [line for line in self.input if line.strip()]
+ and "Empty" not in self.name
+ and not [
+ file
+ for file in self.files
+ # these files are added based on other things
+ if os.path.basename(file[0]) not in ("typing.pyi", "_typeshed.pyi", "builtins.pyi")
+ ]
+ ):
+ raise AssertionError(f"{self.name} is empty.")
+
parent = self.getparent(DataSuiteCollector)
assert parent is not None, "Should not happen"
suite = parent.obj()
