From: Semyon Pupkov <mail@semyonpupkov.com>
Date: Sat, 11 May 2024 12:41:06 +0000 (-0400)
Subject: Optimize has_intersection func
X-Git-Tag: rel_2_0_31~21^2
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=ca7d2e9a482fd0b983c6df3db3ce0b2f4111af1f;p=thirdparty%2Fsqlalchemy%2Fsqlalchemy.git

Optimize has_intersection func

<!-- Provide a general summary of your proposed changes in the Title field above -->

Optimize `has_intersection` function.  It uses in few places, but even so it might be optimized. New version:
1. Does not allocate new set
2. A bit of performance speedup
```
from sqlalchemy import util

import timeit
import functools

a = {1, 2, 3}
b = [2, 3, 4]

t1 = timeit.Timer(functools.partial(util.has_intersection, a, b))
t2 = timeit.Timer(functools.partial(util.has_intersection2, a, b))

print("old", t1.timeit())
print("new", t2.timeit())

old 0.37196154199773446
new 0.29704541599494405

old 0.37331208398973104
new 0.29647241700149607
```

### Description
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### Checklist
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This pull request is:

- [x] A documentation / typographical / small typing error fix
	- Good to go, no issue or tests are needed
- [ ] A short code fix
	- please include the issue number, and create an issue if none exists, which
	  must include a complete example of the issue.  one line code fixes without an
	  issue and demonstration will not be accepted.
	- Please include: `Fixes: #<issue number>` in the commit message
	- please include tests.   one line code fixes without tests will not be accepted.
- [ ] A new feature implementation
	- please include the issue number, and create an issue if none exists, which must
	  include a complete example of how the feature would look.
	- Please include: `Fixes: #<issue number>` in the commit message
	- please include tests.

**Have a nice day!**

Closes: #11378
Pull-request: https://github.com/sqlalchemy/sqlalchemy/pull/11378
Pull-request-sha: 258bf1af7c73c83502eb49240a996f5846c6a0a9

Change-Id: Ic1ec1448641304eba4751f55f1e3c2b217f7f352
(cherry picked from commit 5b43687da6820884c75531e89d6347bf285a3b2c)
---

diff --git a/lib/sqlalchemy/util/_collections.py b/lib/sqlalchemy/util/_collections.py
index e3a8ad834a..9755f8d99e 100644
--- a/lib/sqlalchemy/util/_collections.py
+++ b/lib/sqlalchemy/util/_collections.py
@@ -16,6 +16,7 @@ import typing
 from typing import Any
 from typing import Callable
 from typing import cast
+from typing import Container
 from typing import Dict
 from typing import FrozenSet
 from typing import Generic
@@ -425,15 +426,14 @@ def to_list(x: Any, default: Optional[List[Any]] = None) -> List[Any]:
         return list(x)
 
 
-def has_intersection(set_, iterable):
+def has_intersection(set_: Container[Any], iterable: Iterable[Any]) -> bool:
     r"""return True if any items of set\_ are present in iterable.
 
     Goes through special effort to ensure __hash__ is not called
     on items in iterable that don't support it.
 
     """
-    # TODO: optimize, write in C, etc.
-    return bool(set_.intersection([i for i in iterable if i.__hash__]))
+    return any(i in set_ for i in iterable if i.__hash__)
 
 
 def to_set(x):