rust: Add type annotation to fix inference on Rust Nightly When compiling with Rust Nightly, the im-rs crate silently makes use of the experimental language feature for trait impl specialization. This apperently changes public its APIs in subtle ways such that type inference of some user code can fail where it succeeds when specialization is disabled. This made Mercurial’s Rust unit tests have compilation errors on Nightly. I have not managed to find the exactl root cause, but I wrote down my findings so far at https://github.com/bodil/im-rs/issues/188 This adds type annotation to make unit tests rely less on type inference and work around the issue. Differential Revision: https://phab.mercurial-scm.org/D10742

recover: only apply last journal record per file (issue6423) This got broken in 2019 when the size check was introduced. It is most noticable when dealing with transactions that involve an inline to non-inline revlog storage transaction. It wasn't seen as much at the time because the in-memory journal actually de-duplicated the entry implicity, but since 63edc384d3b7 the on-disk journal is used for rollback as well as recover. Differential Revision: https://phab.mercurial-scm.org/D10726

revlog: update data file record before index rename When migrating from inline to non-inline data storage, the data file is recorded initially as zero sized so that it is removed on failure. But the record has to be updated before the index is renamed, otherwise data is lost on rollback. Differential Revision: https://phab.mercurial-scm.org/D10725