Enforce None check for suffix
@@ -1028,7 +1028,7 @@ class Linter(metaclass=LinterMeta):
def tmpfile(self, cmd, code, suffix=None):
"""Create temporary file with code and lint it."""
- if not suffix:
+ if suffix is None:
suffix = self.get_tempfile_suffix()
with make_temp_file(suffix, code) as file:
