alhudz opened a new pull request, #1709: URL: https://github.com/apache/commons-lang/pull/1709
Thanks for your contribution to [Apache Commons](https://commons.apache.org/)! Your help is appreciated! Before you push a pull request, review this list: - [x] Read the [contribution guidelines](CONTRIBUTING.md) for this project. - [ ] Read the [ASF Generative Tooling Guidance](https://www.apache.org/legal/generative-tooling.html) if you use Artificial Intelligence (AI). - [ ] I used AI to create any part of, or all of, this pull request. Which AI tool was used to create this pull request, and to what extent did it contribute? - [x] Run a successful build using the default [Maven](https://maven.apache.org/) goal with `mvn`; that's `mvn` on the command line by itself. - [x] Write unit tests that match behavioral changes, where the tests fail if the changes to the runtime are not applied. This may not always be possible, but it is a best practice. - [x] Write a pull request description that is detailed enough to understand what the pull request does, how, and why. - [x] Each commit in the pull request should have a meaningful subject line and body. Note that a maintainer may squash commits during the merge process. --- `Fraction.add`/`subtract` go through `addSub`, whose `d1 == 1` fast path (coprime denominators) builds the result numerator with `mulAndCheck(numerator, fraction.denominator)` and `mulAndCheck(fraction.numerator, denominator)`. Those cross products overflow an `int` even when the reduced result is comfortably in range, so `Fraction.getFraction(Integer.MAX_VALUE, 2).add(Fraction.getFraction(-Integer.MAX_VALUE, 1))` throws `ArithmeticException: overflow: mul`. Expected `-2147483647/2`, actual an exception. The sibling `d1 != 1` branch already computes the numerator in wider precision and only rejects the final reduced value. Compute the two cross products and their sum/difference in `long` (both denominators are positive and below `2^31`, so the intermediate values cannot overflow `long`) and reject only when the resulting numerator does not fit an `int`, matching the wider branch. Keeping it inside `addSub` covers `add`, `subtract` and `divideBy`. The two helpers `addAndCheck`/`subAndCheck` were only used by this branch and are removed. Regression cases added to `FractionTest` fail with `overflow: mul` before the change. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
