diff --git a/Lib/copy.py b/Lib/copy.py index a69bc4e78c20b3..7a1907d75494d7 100644 --- a/Lib/copy.py +++ b/Lib/copy.py @@ -121,6 +121,11 @@ def deepcopy(x, memo=None, _nil=[]): See the module's __doc__ string for more info. """ + cls = type(x) + + if cls in _atomic_types: + return x + d = id(x) if memo is None: memo = {} @@ -129,14 +134,12 @@ def deepcopy(x, memo=None, _nil=[]): if y is not _nil: return y - cls = type(x) - copier = _deepcopy_dispatch.get(cls) if copier is not None: y = copier(x, memo) else: if issubclass(cls, type): - y = _deepcopy_atomic(x, memo) + y = x # atomic copy else: copier = getattr(x, "__deepcopy__", None) if copier is not None: @@ -167,26 +170,12 @@ def deepcopy(x, memo=None, _nil=[]): _keep_alive(x, memo) # Make sure x lives at least as long as d return y +_atomic_types = {types.NoneType, types.EllipsisType, types.NotImplementedType, + int, float, bool, complex, bytes, str, types.CodeType, type, range, + types.BuiltinFunctionType, types.FunctionType, weakref.ref, property} + _deepcopy_dispatch = d = {} -def _deepcopy_atomic(x, memo): - return x -d[types.NoneType] = _deepcopy_atomic -d[types.EllipsisType] = _deepcopy_atomic -d[types.NotImplementedType] = _deepcopy_atomic -d[int] = _deepcopy_atomic -d[float] = _deepcopy_atomic -d[bool] = _deepcopy_atomic -d[complex] = _deepcopy_atomic -d[bytes] = _deepcopy_atomic -d[str] = _deepcopy_atomic -d[types.CodeType] = _deepcopy_atomic -d[type] = _deepcopy_atomic -d[range] = _deepcopy_atomic -d[types.BuiltinFunctionType] = _deepcopy_atomic -d[types.FunctionType] = _deepcopy_atomic -d[weakref.ref] = _deepcopy_atomic -d[property] = _deepcopy_atomic def _deepcopy_list(x, memo, deepcopy=deepcopy): y = [] diff --git a/Misc/NEWS.d/next/Library/2024-01-18-21-44-23.gh-issue-114264.DBKn29.rst b/Misc/NEWS.d/next/Library/2024-01-18-21-44-23.gh-issue-114264.DBKn29.rst new file mode 100644 index 00000000000000..069ac68b4f3a95 --- /dev/null +++ b/Misc/NEWS.d/next/Library/2024-01-18-21-44-23.gh-issue-114264.DBKn29.rst @@ -0,0 +1 @@ +Improve performance of :func:`copy.deepcopy` by adding a fast path for atomic types.