-
-
Notifications
You must be signed in to change notification settings - Fork 31.9k
gh-91581: Check result of utc_to_seconds #91582
New issue
Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.
By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.
Already on GitHub? Sign in to your account
Conversation
9113132
to
c22c81d
Compare
c22c81d
to
0242b88
Compare
There was a problem hiding this comment.
Choose a reason for hiding this comment
The reason will be displayed to describe this comment to others. Learn more.
If it does not have user-facing effect, it does not need a NEWS entry. If it changes the error message, it would be worth to add a test for this.
I would add tests for Dec 30, 1 BCE and Dec 31, 1 BCE. |
0242b88
to
7a0af95
Compare
Thanks for the review Serhiy!
It changes the error message but not in any way that I am prepared to make assertions about — this is a mostly cosmetic change for consistency. I'm not even sure that the error message is the same across the C and Python implementations. I generally like to add a NEWS entry for code changes anyway, in case the change had an unexpected effect and someone is looking for hints as to what might have caused the behavior change in the changelog.
Done, and when doing that I refactored the relevant tests to get us a lot closer to the actual limits we're expecting. This turned up some other issues around these edge cases, so I've added this comment to #91012. Fixing that should let us make these tests a lot cleaner. As part of the refactor I ended up tweaking the pure Python implementation of |
There was a problem hiding this comment.
Choose a reason for hiding this comment
The reason will be displayed to describe this comment to others. Learn more.
I have some questions and minor suggestions.
Misc/NEWS.d/next/Library/2022-04-15-13-16-25.gh-issue-91581.9OGsrN.rst
Outdated
Show resolved
Hide resolved
The `utc_to_seconds` call can fail, here's a minimal reproducer on Linux: TZ=UTC python -c "from datetime import *; datetime.fromtimestamp(253402300799 + 1)" The old behavior still raised an error in a similar way, but only because subsequent calculations happened to fail as well. Better to fail fast. This also refactors the tests to split out the `fromtimestamp` and `utcfromtimestamp` tests, and to get us closer to the actual desired limits of the functions. As part of this, we also changed the way we detect platforms where the same limits don't necessarily apply (e.g. Windows). As part of refactoring the tests to hit this condition explicitly (even though the user-facing behvior doesn't change in any way we plan to guarantee), I noticed that there was a difference in the places that `datetime.utcfromtimestamp` fails in the C and pure Python versions, which was fixed by skipping the "probe for fold" logic for UTC specifically — since UTC doesn't have any folds or gaps, we were never going to find a fold value anyway. This should prevent some failures in the pure python `utcfromtimestamp` method on timestamps close to 0001-01-01. There are two separate news entries for this because one is a potentially user-facing change, the other is an internal code correctness change that, if anything, changes some error messages. The two happen to be coupled because of the test refactoring, but they are probably best thought of as independent changes. Fixes pythonGH-91581
28d8ca1
to
55a77c1
Compare
Thanks @pganssle for the PR 🌮🎉.. I'm working now to backport this PR to: 3.9, 3.10, 3.11. |
…thonGH-91582) The `utc_to_seconds` call can fail, here's a minimal reproducer on Linux: TZ=UTC python -c "from datetime import *; datetime.fromtimestamp(253402300799 + 1)" The old behavior still raised an error in a similar way, but only because subsequent calculations happened to fail as well. Better to fail fast. This also refactors the tests to split out the `fromtimestamp` and `utcfromtimestamp` tests, and to get us closer to the actual desired limits of the functions. As part of this, we also changed the way we detect platforms where the same limits don't necessarily apply (e.g. Windows). As part of refactoring the tests to hit this condition explicitly (even though the user-facing behvior doesn't change in any way we plan to guarantee), I noticed that there was a difference in the places that `datetime.utcfromtimestamp` fails in the C and pure Python versions, which was fixed by skipping the "probe for fold" logic for UTC specifically — since UTC doesn't have any folds or gaps, we were never going to find a fold value anyway. This should prevent some failures in the pure python `utcfromtimestamp` method on timestamps close to 0001-01-01. There are two separate news entries for this because one is a potentially user-facing change, the other is an internal code correctness change that, if anything, changes some error messages. The two happen to be coupled because of the test refactoring, but they are probably best thought of as independent changes. Fixes pythonGH-91581 (cherry picked from commit 83c0247) Co-authored-by: Paul Ganssle <[email protected]>
GH-92745 is a backport of this pull request to the 3.11 branch. |
…thonGH-91582) The `utc_to_seconds` call can fail, here's a minimal reproducer on Linux: TZ=UTC python -c "from datetime import *; datetime.fromtimestamp(253402300799 + 1)" The old behavior still raised an error in a similar way, but only because subsequent calculations happened to fail as well. Better to fail fast. This also refactors the tests to split out the `fromtimestamp` and `utcfromtimestamp` tests, and to get us closer to the actual desired limits of the functions. As part of this, we also changed the way we detect platforms where the same limits don't necessarily apply (e.g. Windows). As part of refactoring the tests to hit this condition explicitly (even though the user-facing behvior doesn't change in any way we plan to guarantee), I noticed that there was a difference in the places that `datetime.utcfromtimestamp` fails in the C and pure Python versions, which was fixed by skipping the "probe for fold" logic for UTC specifically — since UTC doesn't have any folds or gaps, we were never going to find a fold value anyway. This should prevent some failures in the pure python `utcfromtimestamp` method on timestamps close to 0001-01-01. There are two separate news entries for this because one is a potentially user-facing change, the other is an internal code correctness change that, if anything, changes some error messages. The two happen to be coupled because of the test refactoring, but they are probably best thought of as independent changes. Fixes pythonGH-91581 (cherry picked from commit 83c0247) Co-authored-by: Paul Ganssle <[email protected]>
GH-92746 is a backport of this pull request to the 3.10 branch. |
…thonGH-91582) The `utc_to_seconds` call can fail, here's a minimal reproducer on Linux: TZ=UTC python -c "from datetime import *; datetime.fromtimestamp(253402300799 + 1)" The old behavior still raised an error in a similar way, but only because subsequent calculations happened to fail as well. Better to fail fast. This also refactors the tests to split out the `fromtimestamp` and `utcfromtimestamp` tests, and to get us closer to the actual desired limits of the functions. As part of this, we also changed the way we detect platforms where the same limits don't necessarily apply (e.g. Windows). As part of refactoring the tests to hit this condition explicitly (even though the user-facing behvior doesn't change in any way we plan to guarantee), I noticed that there was a difference in the places that `datetime.utcfromtimestamp` fails in the C and pure Python versions, which was fixed by skipping the "probe for fold" logic for UTC specifically — since UTC doesn't have any folds or gaps, we were never going to find a fold value anyway. This should prevent some failures in the pure python `utcfromtimestamp` method on timestamps close to 0001-01-01. There are two separate news entries for this because one is a potentially user-facing change, the other is an internal code correctness change that, if anything, changes some error messages. The two happen to be coupled because of the test refactoring, but they are probably best thought of as independent changes. Fixes pythonGH-91581 (cherry picked from commit 83c0247) Co-authored-by: Paul Ganssle <[email protected]>
GH-92748 is a backport of this pull request to the 3.9 branch. |
…-91582) The `utc_to_seconds` call can fail, here's a minimal reproducer on Linux: TZ=UTC python -c "from datetime import *; datetime.fromtimestamp(253402300799 + 1)" The old behavior still raised an error in a similar way, but only because subsequent calculations happened to fail as well. Better to fail fast. This also refactors the tests to split out the `fromtimestamp` and `utcfromtimestamp` tests, and to get us closer to the actual desired limits of the functions. As part of this, we also changed the way we detect platforms where the same limits don't necessarily apply (e.g. Windows). As part of refactoring the tests to hit this condition explicitly (even though the user-facing behvior doesn't change in any way we plan to guarantee), I noticed that there was a difference in the places that `datetime.utcfromtimestamp` fails in the C and pure Python versions, which was fixed by skipping the "probe for fold" logic for UTC specifically — since UTC doesn't have any folds or gaps, we were never going to find a fold value anyway. This should prevent some failures in the pure python `utcfromtimestamp` method on timestamps close to 0001-01-01. There are two separate news entries for this because one is a potentially user-facing change, the other is an internal code correctness change that, if anything, changes some error messages. The two happen to be coupled because of the test refactoring, but they are probably best thought of as independent changes. Fixes GH-91581 (cherry picked from commit 83c0247) Co-authored-by: Paul Ganssle <[email protected]>
…-91582) The `utc_to_seconds` call can fail, here's a minimal reproducer on Linux: TZ=UTC python -c "from datetime import *; datetime.fromtimestamp(253402300799 + 1)" The old behavior still raised an error in a similar way, but only because subsequent calculations happened to fail as well. Better to fail fast. This also refactors the tests to split out the `fromtimestamp` and `utcfromtimestamp` tests, and to get us closer to the actual desired limits of the functions. As part of this, we also changed the way we detect platforms where the same limits don't necessarily apply (e.g. Windows). As part of refactoring the tests to hit this condition explicitly (even though the user-facing behvior doesn't change in any way we plan to guarantee), I noticed that there was a difference in the places that `datetime.utcfromtimestamp` fails in the C and pure Python versions, which was fixed by skipping the "probe for fold" logic for UTC specifically — since UTC doesn't have any folds or gaps, we were never going to find a fold value anyway. This should prevent some failures in the pure python `utcfromtimestamp` method on timestamps close to 0001-01-01. There are two separate news entries for this because one is a potentially user-facing change, the other is an internal code correctness change that, if anything, changes some error messages. The two happen to be coupled because of the test refactoring, but they are probably best thought of as independent changes. Fixes GH-91581 (cherry picked from commit 83c0247) Co-authored-by: Paul Ganssle <[email protected]>
…-91582) (GH-92748) The `utc_to_seconds` call can fail, here's a minimal reproducer on Linux: TZ=UTC python -c "from datetime import *; datetime.fromtimestamp(253402300799 + 1)" The old behavior still raised an error in a similar way, but only because subsequent calculations happened to fail as well. Better to fail fast. This also refactors the tests to split out the `fromtimestamp` and `utcfromtimestamp` tests, and to get us closer to the actual desired limits of the functions. As part of this, we also changed the way we detect platforms where the same limits don't necessarily apply (e.g. Windows). As part of refactoring the tests to hit this condition explicitly (even though the user-facing behvior doesn't change in any way we plan to guarantee), I noticed that there was a difference in the places that `datetime.utcfromtimestamp` fails in the C and pure Python versions, which was fixed by skipping the "probe for fold" logic for UTC specifically — since UTC doesn't have any folds or gaps, we were never going to find a fold value anyway. This should prevent some failures in the pure python `utcfromtimestamp` method on timestamps close to 0001-01-01. There are two separate news entries for this because one is a potentially user-facing change, the other is an internal code correctness change that, if anything, changes some error messages. The two happen to be coupled because of the test refactoring, but they are probably best thought of as independent changes. Fixes GH-91581 (cherry picked from commit 83c0247) Co-authored-by: Paul Ganssle <[email protected]>
…thonGH-91582) (pythonGH-92748) The `utc_to_seconds` call can fail, here's a minimal reproducer on Linux: TZ=UTC python -c "from datetime import *; datetime.fromtimestamp(253402300799 + 1)" The old behavior still raised an error in a similar way, but only because subsequent calculations happened to fail as well. Better to fail fast. This also refactors the tests to split out the `fromtimestamp` and `utcfromtimestamp` tests, and to get us closer to the actual desired limits of the functions. As part of this, we also changed the way we detect platforms where the same limits don't necessarily apply (e.g. Windows). As part of refactoring the tests to hit this condition explicitly (even though the user-facing behvior doesn't change in any way we plan to guarantee), I noticed that there was a difference in the places that `datetime.utcfromtimestamp` fails in the C and pure Python versions, which was fixed by skipping the "probe for fold" logic for UTC specifically — since UTC doesn't have any folds or gaps, we were never going to find a fold value anyway. This should prevent some failures in the pure python `utcfromtimestamp` method on timestamps close to 0001-01-01. There are two separate news entries for this because one is a potentially user-facing change, the other is an internal code correctness change that, if anything, changes some error messages. The two happen to be coupled because of the test refactoring, but they are probably best thought of as independent changes. Fixes pythonGH-91581 (cherry picked from commit 83c0247) Co-authored-by: Paul Ganssle <[email protected]>
This result could fail. On Linux here's a minimal reproducer:
The old behavior still raised an error in a similar way, but only because subsequent calculations happened to fail as well. Better to fail fast.
Fixes GH-91581