Use and test parent stack level

legacy_api_wrap.py

@@ -73,6 +73,7 @@ def fn_compatible(*args, **kw):
                         f"The specified parameters {old_positionals[:len(args_rest)]!r} are no longer positional. "
                         f"Please specify them like `{old_positionals[0]}={args_rest[0]!r}`",
                         DeprecationWarning,
+                        stacklevel=2,
                     )
                     kw = {**kw, **dict(zip(old_positionals, args_rest))}
 

tests.py

@@ -1,5 +1,8 @@
+import warnings
 from inspect import signature
 
+import pytest
+
 from legacy_api_wrap import legacy_api
 
 
@@ -19,13 +22,18 @@ def test_new_param_available():
 
 
 def test_old_positional_order():
-    from pytest import warns
-
-    with warns(DeprecationWarning):
+    with pytest.deprecated_call():
         res = new(12, 13, 14)
     assert res["d"] == 14
 
 
+def test_warning_stack():
+    with pytest.deprecated_call() as record:
+        new(12, 13, 14)
+    w = record.pop()  # type: warnings.WarningMessage
+    assert w.filename == __file__
+
+
 def test_too_many_args():
     from pytest import raises