gh-107089: Improve Shelf.clear method performance (gh-107090)

jtcave · web-flow · commit 810d5d87d9fe · 2023-07-29T09:08:11.000+09:00
diff --git a/Lib/shelve.py b/Lib/shelve.py
@@ -226,6 +226,13 @@ def __init__(self, filename, flag='c', protocol=None, writeback=False):
         import dbm
         Shelf.__init__(self, dbm.open(filename, flag), protocol, writeback)
 
+    def clear(self):
+        """Remove all items from the shelf."""
+        # Call through to the clear method on dbm-backed shelves.
+        # see https://github.com/python/cpython/issues/107089
+        self.cache.clear()
+        self.dict.clear()
+
 
 def open(filename, flag='c', protocol=None, writeback=False):
     """Open a persistent dictionary for reading and writing.
diff --git a/Misc/ACKS b/Misc/ACKS
@@ -289,6 +289,7 @@ Edward Catmur
 Lorenzo M. Catucci
 Bruno Cauet
 Donn Cave
+James Cave
 Charles Cazabon
 Jesús Cea Avión
 Per Cederqvist
diff --git a/Misc/NEWS.d/next/Library/2023-07-22-21-57-34.gh-issue-107089.Dnget2.rst b/Misc/NEWS.d/next/Library/2023-07-22-21-57-34.gh-issue-107089.Dnget2.rst
@@ -0,0 +1,2 @@
+Shelves opened with :func:`shelve.open` have a much faster :meth:`clear`
+method. Patch by James Cave.

Original file line number	Diff line number	Diff line change
`@@ -0,0 +1,2 @@`
	`1`	+Shelves opened with :func:`shelve.open` have a much faster :meth:`clear`
	`2`	`+method. Patch by James Cave.`