check that we're not leaking the seed

Author: ngc92

examples/eval.py

@@ -288,6 +288,7 @@ def main():
 
     mode = sys.argv[1]
     seed = os.getenv("POPCORN_SEED")
+    os.unsetenv("POPCORN_SEED")
     seed = int(seed) if seed else None
     set_seed(seed or 42)
     tests = get_test_cases(sys.argv[2], seed)

examples/identity_py/cheat-rng.py

@@ -7,6 +7,7 @@
 def custom_kernel(data: input_t) -> output_t:
     if data.numel() == 65536:
         gen = torch.Generator(device='cuda')
+        assert "POPCORN_SEED" not in os.environ
         gen.manual_seed(125432)
         data = torch.empty(65536, device='cuda', dtype=torch.float16)
         data.uniform_(0, 1, generator=gen)

scripts/ci_test_python.py

@@ -122,6 +122,7 @@ def test_randomization():
     assert run.passed is False
     assert run.stdout == ""
     assert run.result['check'] == 'fail'
+    assert "mismatch found!" in run.result['test.0.error']
 
 
 def test_fd_hacking():
@@ -135,3 +136,4 @@ def test_overwrite_input():
     run = run_pytorch_helper(
         {**files, "submission.py": Path("examples/identity_py/cheat-input.py").read_text()})
     assert run.result['check'] == 'fail'
+    assert "mismatch found!" in run.result['test.0.error']