rootvector2 opened a new pull request, #728: URL: https://github.com/apache/commons-collections/pull/728
`AbstractSortedMapDecorator.nextKey` walks `tailMap(key)` and discards the first element to step over `key` itself, but never checks that `key` is present. When `key` is absent that first element is the successor, so it gets dropped and the wrong key comes back; when `key` is at or past the end `tailMap` is empty and `it.next()` throws `NoSuchElementException` instead of returning `null`. `DualTreeBidiMap.nextKey` repeats the same `tailMap().iterator().next()` shape and fails the same two ways, since its `isEmpty()` guard only covers a fully empty map. Return `null` when the map does not contain `key`, matching the documented `null if no match` contract and every other `nextKey` in the library (`AbstractLinkedMap`, `ListOrderedMap`, `TreeBidiMap`, `PatriciaTrie` all return `null` for an absent key); the skip-first logic then runs only for a present key, the case it was written for. `FixedSizeSortedMap` and `UnmodifiableSortedMap` inherit the decorator fix. Found by auditing the `OrderedMap.nextKey` implementations against the contract. - [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. -- 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]
