Handle untyped interfaces in _check

src/nnbench/runner.py

@@ -28,15 +28,25 @@ def _check(params: dict[str, Any], benchmarks: list[Benchmark]) -> None:
                 )
 
             param_type = param.annotation
+
+            if param_type == inspect.Parameter.empty:
+                logger.debug(f"Found untyped parameter {name!r} in benchmark {bm.fn.__name__!r}.")
+
             if name in benchmark_interface and benchmark_interface[name].annotation != param_type:
                 orig_type = benchmark_interface[name].annotation
                 raise TypeError(
                     f"got non-unique types {orig_type}, {param_type} for parameter {name!r}"
                 )
             benchmark_interface[name] = param
+
     for name, param in benchmark_interface.items():
         if name not in param_types and param.default == inspect.Parameter.empty:
             raise ValueError(f"missing value for required parameter {name!r}")
+
+        if param.annotation == inspect.Parameter.empty:
+            continue
+
+        # only check type match if type supplied
         if not issubclass(param_types[name], param.annotation):
             raise TypeError(
                 f"expected type {param.annotation} for parameter {name!r}, "

tests/test_argcheck.py

@@ -33,3 +33,10 @@ def test_log_warn_on_overwrite_default(
     with caplog.at_level(logging.DEBUG):
         r.run(benchmark, params={"a": 1})
     assert "using value 1 instead of default" in caplog.text
+
+
+def test_untyped_interface(typecheckfolder: str) -> None:
+    benchmarks = os.path.join(typecheckfolder, "untyped_benchmarks.py")
+
+    r = runner.AbstractBenchmarkRunner()
+    r.run(benchmarks, params={"value": 2})

tests/typechecking/untyped_benchmarks.py

@@ -0,0 +1,6 @@
+import nnbench
+
+
+@nnbench.benchmark
+def increment(value):
+    return value + 1