bpo-43475: Fix worst case collision behavior for NaN instances (GH-25493)
diff --git a/Doc/library/stdtypes.rst b/Doc/library/stdtypes.rst
index 68b6050..b83d0d8 100644
--- a/Doc/library/stdtypes.rst
+++ b/Doc/library/stdtypes.rst
@@ -692,10 +692,9 @@
as ``-hash(-x)``. If the resulting hash is ``-1``, replace it with
``-2``.
-- The particular values ``sys.hash_info.inf``, ``-sys.hash_info.inf``
- and ``sys.hash_info.nan`` are used as hash values for positive
- infinity, negative infinity, or nans (respectively). (All hashable
- nans have the same hash value.)
+- The particular values ``sys.hash_info.inf`` and ``-sys.hash_info.inf``
+ are used as hash values for positive
+ infinity or negative infinity (respectively).
- For a :class:`complex` number ``z``, the hash values of the real
and imaginary parts are combined by computing ``hash(z.real) +
@@ -740,7 +739,7 @@
"""Compute the hash of a float x."""
if math.isnan(x):
- return sys.hash_info.nan
+ return super().__hash__()
elif math.isinf(x):
return sys.hash_info.inf if x > 0 else -sys.hash_info.inf
else:
diff --git a/Doc/library/sys.rst b/Doc/library/sys.rst
index e431d1b..fe1cca1 100644
--- a/Doc/library/sys.rst
+++ b/Doc/library/sys.rst
@@ -855,7 +855,7 @@
+---------------------+--------------------------------------------------+
| :const:`inf` | hash value returned for a positive infinity |
+---------------------+--------------------------------------------------+
- | :const:`nan` | hash value returned for a nan |
+ | :const:`nan` | (this attribute is no longer used) |
+---------------------+--------------------------------------------------+
| :const:`imag` | multiplier used for the imaginary part of a |
| | complex number |