On Tue, 14 Mar 2023 22:16:45 GMT, Justin Lu <j...@openjdk.org> wrote:
> This PR fixes the bug which occurred when `Calendar.roll(WEEK_OF_YEAR)` > rolled into a minimal first week with an invalid `WEEK_OF_YEAR` and > `DAY_OF_WEEK` combo. > > For example, Rolling _Monday, 30 December 2019_ by 1 week produced _Monday, > 31 December 2018_, which is incorrect. This is because `WEEK_OF_YEAR` is > rolled from 52 to 1, and the original `DAY_OF_WEEK` is 1. However, there is > no Monday in week 1 of 2019. This is exposed when a future method calls > `Calendar.complete()`, which eventually calculates a `fixedDate` with the > invalid `WEEK_OF_YEAR` and `DAY_OF_WEEK` combo. > > To prevent this, a check is added for rolls into week 1, which determines if > the first week is minimal. If it is indeed minimal, then it is checked if > `DAY_OF_WEEK` exists in that week, if not, `WEEK_OF_YEAR` must be incremented > by one. > > After the fix, Rolling _Monday, 30 December 2019_ by 1 week produces _Monday, > 7 January 2019_ This pull request has now been integrated. Changeset: a324fa26 Author: Justin Lu <j...@openjdk.org> Committer: Naoto Sato <na...@openjdk.org> URL: https://git.openjdk.org/jdk/commit/a324fa2639d29f0c5b2928e7f15ec67e396c2648 Stats: 188 lines in 2 files changed: 186 ins; 0 del; 2 mod 8225641: Calendar.roll(int field) does not work correctly for WEEK_OF_YEAR Reviewed-by: naoto ------------- PR: https://git.openjdk.org/jdk/pull/13031
