Faster copies of slotted objects, Accidental, and Pitch

music21/common/objects.py

@@ -159,6 +159,8 @@ def __call__(self) -> int:
 
 # ------------------------------------------------------------------------------
 
+_slotsByClass: dict[type, frozenset[str]] = {}
+
 
 class SlottedObjectMixin:
     r'''
@@ -223,9 +225,9 @@ def __setstate__(self, state: dict[str, t.Any]) -> None:
         for slot, value in state.items():
             setattr(self, slot, value)
 
-    def _getSlotsRecursive(self) -> set[str]:
+    def _getSlotsRecursive(self) -> frozenset[str]:
         '''
-        Find all slots recursively.
+        Find all slots recursively.  Cached per class.
 
         A private attribute so as not to change the contents of inheriting
         objects private interfaces:
@@ -250,10 +252,16 @@ def _getSlotsRecursive(self) -> set[str]:
         ['_editorial', '_style', 'direction', 'funkiness', 'groovability',
             'id', 'independentAngle', 'number', 'type']
         '''
+        try:
+            return _slotsByClass[type(self)]
+        except KeyError:
+            pass
         slots: set[str] = set()
         for cls in self.__class__.mro():
             slots.update(getattr(cls, '__slots__', ()))
-        return slots
+        frozenSlots = frozenset(slots)
+        _slotsByClass[type(self)] = frozenSlots
+        return frozenSlots
 
 
 class EqualSlottedObjectMixin(SlottedObjectMixin):

music21/pitch.py

@@ -1057,13 +1057,8 @@ class Accidental(prebase.ProtoM21Object, style.StyleMixin):
 
     # INITIALIZER #
 
-    def __init__(  # pylint: disable=super-init-not-called
-        self,
-        specifier: int|str|float = 'natural',
-    ) -> None:
-        # StyleMixin.__init__, inlined for speed; keep in sync
-        self._style = None
-        self._editorial = None
+    def __init__(self, specifier: int|str|float = 'natural') -> None:
+        super().__init__()
         # managed by properties
         self._displayType = 'normal'
         # normal, always, never, if-absolutely-necessary,