python · hongweipeng · Nov 18, 2020 · Nov 18, 2020 · Nov 21, 2020 · Dec 3, 2020
diff --git a/Lib/enum.py b/Lib/enum.py
@@ -785,7 +785,7 @@ def __contains__(self, other):

    def __iter__(self):
        members, extra_flags = _decompose(self.__class__, self.value)
-        return (m for m in members if m._value_ != 0)
+        return (m for m in members if m._value_.bit_count() == 1)

    def __repr__(self):
        cls = self.__class__

diff --git a/Lib/test/test_enum.py b/Lib/test/test_enum.py
@@ -2413,6 +2413,17 @@ def test_member_iter(self):
        self.assertEqual(list(Color.BLUE), [Color.BLUE])
        self.assertEqual(list(Color.GREEN), [Color.GREEN])

+    def test_member_iter_one_bit(self):
+        class Foo(Flag):
+            NONE = 0
+            A = 1
+            B = 2
+            C = 4
+            AB = A | B
+            ABC = A | B | C
+
+        self.assertEqual(list(Foo.ABC), [Foo.C, Foo.B, Foo.A])
+
    def test_auto_number(self):
        class Color(Flag):
            red = auto()

diff --git a/Misc/NEWS.d/next/Library/2020-11-18-22-38-23.bpo-32218.hCjZSQ.rst b/Misc/NEWS.d/next/Library/2020-11-18-22-38-23.bpo-32218.hCjZSQ.rst
@@ -0,0 +1,2 @@
+Only keep the single-bit members for :meth:`enum.Flag.__iter__` in :mod:`enum`.
+Patch by Weipeng Hong.
Original file line number	Diff line number	Diff line change
		@@ -0,0 +1,2 @@
		Only keep the single-bit members for :meth:`enum.Flag.__iter__` in :mod:`enum`.
		Patch by Weipeng Hong.