Convert a couple of places to use config store

src/_pytest/assertion/__init__.py

@@ -7,6 +7,7 @@
 from _pytest.assertion import rewrite
 from _pytest.assertion import truncate
 from _pytest.assertion import util
+from _pytest.assertion.rewrite import assertstate_key
 from _pytest.compat import TYPE_CHECKING
 from _pytest.config import hookimpl
 
@@ -82,13 +83,13 @@ def __init__(self, config, mode):
 
 def install_importhook(config):
     """Try to install the rewrite hook, raise SystemError if it fails."""
-    config._assertstate = AssertionState(config, "rewrite")
-    config._assertstate.hook = hook = rewrite.AssertionRewritingHook(config)
+    config._store[assertstate_key] = AssertionState(config, "rewrite")
+    config._store[assertstate_key].hook = hook = rewrite.AssertionRewritingHook(config)
     sys.meta_path.insert(0, hook)
-    config._assertstate.trace("installed rewrite import hook")
+    config._store[assertstate_key].trace("installed rewrite import hook")
 
     def undo():
-        hook = config._assertstate.hook
+        hook = config._store[assertstate_key].hook
         if hook is not None and hook in sys.meta_path:
             sys.meta_path.remove(hook)
 
@@ -100,7 +101,7 @@ def pytest_collection(session: "Session") -> None:
     # this hook is only called when test modules are collected
     # so for example not in the master process of pytest-xdist
     # (which does not collect test modules)
-    assertstate = getattr(session.config, "_assertstate", None)
+    assertstate = session.config._store.get(assertstate_key, None)
     if assertstate:
         if assertstate.hook is not None:
             assertstate.hook.set_session(session)
@@ -163,7 +164,7 @@ def call_assertion_pass_hook(lineno, orig, expl):
 
 
 def pytest_sessionfinish(session):
-    assertstate = getattr(session.config, "_assertstate", None)
+    assertstate = session.config._store.get(assertstate_key, None)
     if assertstate:
         if assertstate.hook is not None:
             assertstate.hook.set_session(None)

src/_pytest/assertion/rewrite.py

@@ -26,9 +26,18 @@
     format_explanation as _format_explanation,
 )
 from _pytest.compat import fspath
+from _pytest.compat import TYPE_CHECKING
 from _pytest.pathlib import fnmatch_ex
 from _pytest.pathlib import Path
 from _pytest.pathlib import PurePath
+from _pytest.store import StoreKey
+
+if TYPE_CHECKING:
+    from _pytest.assertion import AssertionState  # noqa: F401
+
+
+assertstate_key = StoreKey["AssertionState"]()
+
 
 # pytest caches rewritten pycs in pycache dirs
 PYTEST_TAG = "{}-pytest-{}".format(sys.implementation.cache_tag, version)
@@ -65,7 +74,7 @@ def set_session(self, session):
     def find_spec(self, name, path=None, target=None):
         if self._writing_pyc:
             return None
-        state = self.config._assertstate
+        state = self.config._store[assertstate_key]
         if self._early_rewrite_bailout(name, state):
             return None
         state.trace("find_module called for: %s" % name)
@@ -104,7 +113,7 @@ def create_module(self, spec):
 
     def exec_module(self, module):
         fn = Path(module.__spec__.origin)
-        state = self.config._assertstate
+        state = self.config._store[assertstate_key]
 
         self._rewritten_names.add(module.__name__)
 

src/_pytest/mark/evaluate.py

@@ -2,21 +2,28 @@
 import platform
 import sys
 import traceback
+from typing import Any
+from typing import Dict
 
 from ..outcomes import fail
 from ..outcomes import TEST_OUTCOME
+from _pytest.config import Config
+from _pytest.store import StoreKey
 
 
-def cached_eval(config, expr, d):
-    if not hasattr(config, "_evalcache"):
-        config._evalcache = {}
+evalcache_key = StoreKey[Dict[str, Any]]()
+
+
+def cached_eval(config: Config, expr: str, d: Dict[str, object]) -> Any:
+    default = {}  # type: Dict[str, object]
+    evalcache = config._store.setdefault(evalcache_key, default)
     try:
-        return config._evalcache[expr]
+        return evalcache[expr]
     except KeyError:
         import _pytest._code
 
         exprcode = _pytest._code.compile(expr, mode="eval")
-        config._evalcache[expr] = x = eval(exprcode, d)
+        evalcache[expr] = x = eval(exprcode, d)
         return x
 
 

src/_pytest/store.py

@@ -104,6 +104,15 @@ def get(self, key: StoreKey[T], default: D) -> Union[T, D]:
         except KeyError:
             return default
 
+    def setdefault(self, key: StoreKey[T], default: T) -> T:
+        """Return the value of key if already set, otherwise set the value
+        of key to default and return default."""
+        try:
+            return self[key]
+        except KeyError:
+            self[key] = default
+            return default
+
     def __delitem__(self, key: StoreKey[T]) -> None:
         """Delete the value for key.
 

testing/test_store.py

@@ -37,6 +37,14 @@ def test_store() -> None:
     with pytest.raises(KeyError):
         store[key1]
 
+    # setdefault
+    store[key1] = "existing"
+    assert store.setdefault(key1, "default") == "existing"
+    assert store[key1] == "existing"
+    key_setdefault = StoreKey[bytes]()
+    assert store.setdefault(key_setdefault, b"default") == b"default"
+    assert store[key_setdefault] == b"default"
+
     # Can't accidentally add attributes to store object itself.
     with pytest.raises(AttributeError):
         store.foo = "nope"  # type: ignore[attr-defined] # noqa: F821