On Thu, 3 Sep 2026 13:42:06 GMT, Viktor Klang <[email protected]> wrote:
>> ## Summary >> >> [`JDK-8223933`](https://bugs.openjdk.org/browse/JDK-8223933) >> >> `Stream.distinct()` must remove duplicates according to `Object.equals`. On >> sorted streams it only compared each element to the previous one, which >> fails when `compareTo` is inconsistent with `equals`, so duplicates can >> still be emitted. >> >> ## Fix >> Keep the sorted-path consecutive check, and also track emitted elements in a >> `HashSet` so uniqueness always follows `equals`. Add a regression test for >> the reported case and for equals-duplicates in different sort groups. >> >> --------- >> - [x] I confirm that I make this contribution in accordance with the >> [OpenJDK Interim AI Policy](https://openjdk.org/legal/ai). > > Just weighing in: I suspect that this isn't really solvable without risking > breakage. If `sorted()` is to also enforce that `prev.compareTo(next)` is > aligned with the result of `prev.equals(next)` then usages that are currently > working will cease to work: > > > jshell> (new BigDecimal("0.0")).compareTo(new BigDecimal("0.00")) > $1 ==> 0 > > jshell> (new BigDecimal("0.0")).equals(new BigDecimal("0.00")) > $2 ==> false > > > If instead a distinct() following a sorted() always re-processes the entire > Stream, then it would risk changing the output of existing Stream usages > (silently). 🤔 @viktorklang-ora right. Honestly, I would leave it as is. ------------- PR Comment: https://git.openjdk.org/jdk/pull/32670#issuecomment-5527123361
