Distinct cache keys when api_version=None

hypothesis-python/src/hypothesis/extra/array_api.py

@@ -1076,7 +1076,7 @@ def complex_dtypes(
 
     namespace = StrategiesNamespace(**kwargs)
     try:
-        _args_to_xps[(xp, api_version)] = namespace
+        _args_to_xps[(xp, None if inferred_version else api_version)] = namespace
     except TypeError:
         pass
 

hypothesis-python/tests/array_api/test_strategies_namespace.py

@@ -21,20 +21,32 @@
 )
 from hypothesis.strategies import SearchStrategy
 
+pytestmark = pytest.mark.filterwarnings("ignore::hypothesis.errors.HypothesisWarning")
 
-@pytest.mark.filterwarnings("ignore::hypothesis.errors.HypothesisWarning")
-def test_caching(xp, monkeypatch):
+
+class HashableArrayModuleFactory:
+    """
+    mock_xp cannot be hashed and thus cannot be used in our cache. So just for
+    the purposes of testing the cache, we wrap it with an unsafe hash method.
+    """
+
+    def __getattr__(self, name):
+        return getattr(mock_xp, name)
+
+    def __hash__(self):
+        return hash(tuple(sorted(mock_xp.__dict__)))
+
+
+@pytest.mark.parametrize("api_version", ["2021.12", None])
+def test_caching(api_version, monkeypatch):
     """Caches namespaces respective to arguments."""
-    try:
-        hash(xp)
-    except TypeError:
-        pytest.skip("xp not hashable")
-    assert isinstance(array_api._args_to_xps, WeakValueDictionary)
+    xp = HashableArrayModuleFactory()
+    assert isinstance(array_api._args_to_xps, WeakValueDictionary)  # sanity check
     monkeypatch.setattr(array_api, "_args_to_xps", WeakValueDictionary())
     assert len(array_api._args_to_xps) == 0  # sanity check
-    xps1 = array_api.make_strategies_namespace(xp, api_version="2021.12")
+    xps1 = array_api.make_strategies_namespace(xp, api_version=api_version)
     assert len(array_api._args_to_xps) == 1
-    xps2 = array_api.make_strategies_namespace(xp, api_version="2021.12")
+    xps2 = array_api.make_strategies_namespace(xp, api_version=api_version)
     assert len(array_api._args_to_xps) == 1
     assert isinstance(xps2, SimpleNamespace)
     assert xps2 is xps1
@@ -43,7 +55,28 @@ def test_caching(xp, monkeypatch):
     assert len(array_api._args_to_xps) == 0
 
 
-@pytest.mark.filterwarnings("ignore::hypothesis.errors.HypothesisWarning")
+@pytest.mark.parametrize(
+    "api_version1, api_version2", [(None, "2021.12"), ("2021.12", None)]
+)
+def test_inferred_namespace_is_cached_seperately(
+    api_version1, api_version2, monkeypatch
+):
+    """Results from inferred versions do not share the same cache key as results
+    from specified versions."""
+    xp = HashableArrayModuleFactory()
+    xp.__array_api_version__ = "2021.12"
+    assert isinstance(array_api._args_to_xps, WeakValueDictionary)  # sanity check
+    monkeypatch.setattr(array_api, "_args_to_xps", WeakValueDictionary())
+    assert len(array_api._args_to_xps) == 0  # sanity check
+    xps1 = array_api.make_strategies_namespace(xp, api_version=api_version1)
+    assert xps1.api_version == "2021.12"  # sanity check
+    assert len(array_api._args_to_xps) == 1
+    xps2 = array_api.make_strategies_namespace(xp, api_version=api_version2)
+    assert xps2.api_version == "2021.12"  # sanity check
+    assert len(array_api._args_to_xps) == 2
+    assert xps2 is not xps1
+
+
 def test_complex_dtypes_raises_on_2021_12():
     """Accessing complex_dtypes() for 2021.12 strategy namespace raises helpful
     error, but accessing on future versions returns expected strategy."""