rootvector2 opened a new pull request, #717: URL: https://github.com/apache/commons-collections/pull/717
`AbstractMultiValuedMap.WrappedCollection.addAll` stores a freshly created backing collection in the map before running the add that fills it, so `get(key).addAll(emptyCollection)` reports no change yet leaves `key` mapped to an empty collection. `AbstractListValuedMap.WrappedList.add(int, value)` has the same shape and leaves an empty list behind when the index is out of range and the insert throws. Both break the invariant every remove path keeps, that a key never maps to an empty collection; found by comparing these `get(key)` mutators against `put(K, V)`. `put(K, V)` already does this right, adding to the new collection first and storing it only once the add changed something. The wrapped `addAll` and indexed `add` now follow that order, so a no-op argument or a rejected index leaves the backing map untouched. - [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]
