relnotes/6.7

clone: properly exclude rev-branch-cache from post clone cache warming

When adding "CACHE_REV_BRANCH" to "CACHES_ALL" in e51161b12c7e, I did not
expected it to impact the clone steps. However the "CACHES_POST_CLONE" set is
created rather creatively. (we should fix that, but not on stable)

The benchmark caught a quite significant slowdown one hardlink and ssh-stream
clones. Such slow down can be reduced to around ~5% by fully warming the cache
before the clone. However keeping this expensive step away from the clone
operation fully fix the slowdown and preserve the initial intend.


Example slowdow for hardlink clone

### benchmark.name                               = hg.command.clone
  # bin-env-vars.hg.flavor                       = default
  # bin-env-vars.hg.py-re2-module                = default
  # benchmark.variants.explicit-rev              = none
  # benchmark.variants.issue6528                 = default
  # benchmark.variants.protocol                  = local-hardlink
  # benchmark.variants.pulled-delta-reuse-policy = default
  # benchmark.variants.resource-usage            = default
  # benchmark.variants.validate                  = default
 ## data-env-vars.name = netbeans-2018-08-01-zstd-sparse-revlog
6.8.2:  19.799752
6.9rc0: 29.017493  (+46.55%, +9.22)
after:  19.929341

 ## data-env-vars.name = mercurial-public-2018-08-01-zstd-sparse-revlog
6.8.2:  0.468020
6.9rc0: 1.701294 (+263.51%, +1.23)
after:  0.471934

 ## data-env-vars.name = pypy-2024-03-22-zstd-sparse-revlog
6.8.2:  2.397564
6.9rc0: 5.666641 (+137.41%, +3.28)
after:  2.428085

= Mercurial 6.7.4 =

Exceptional release following a critical regression causing possible data loss
in certain conditions:

 * inline-changelog: fix a critical bug in write_pending that delete data (3cf9e52f5e27)
 * inline-changelog: fix pending transaction visibility when splitting (1721d983dd6d)

Other changes in this release:

 * exchange: fix locking to actually be scoped
 * chistedit: change action for the correct item
 * rust-status: sort the failed matches when printing them
 * hooks: add a prewlock and a prelock hooks
 * bookmark: fix remote bookmark deletion when the push is raced

= Mercurial 6.7.3 =

/!\ This release contains a bug causing possible data loss, use 6.7.4 instead.

 * setup: display return code information about failed `hg` call
 * bundle-spec: properly identify changegroup-less bundle
 * bundle-spec: properly parse boolean configuration as boolean
 * matchers: fix the bug in rust PatternMatcher that made it cut off early
 * match: fix the "visitdir" method on "rootfilesin" matchers
 * match: fix the rust-side bug in visit_children_set for rootfilesin matchers
 * match: strengthen visit_children_set invariant, Recursive means "all files"
 * wireprotoserver: ensure that output stream gets flushed on exception
 * re2: make errors quiet
 * dirstate-v2: add check of parent/child nodes being related when writing
 * dirstate-v2: check that root nodes are at the root before writing
 * rust-cpython: don't swallow the dirstate error message
 * rust: blanket implementation of Graph for Graph references
 * Various fixes to `admin::verify`

= Mercurial 6.7.2 =

/!\ This release contains a bug causing possible data loss, use 6.7.4 instead.

Exceptional release following a large performance regression when cloning.

We are setting up automated benchmarks to reduce the likelihood of regressions
of the sort from happening in the future.

 * phases: avoid a potentially costly dictionary interation in some case
 * phases: update the phase set as we go during retract boundary
 * bundle2: make the "hgtagsfnodes" part advisory

= Mercurial 6.7.1 =

/!\ This release contains a bug causing possible data loss, use 6.7.4 instead.

Exceptional release following a crash found in delta code that can be triggered
with complex repository shapes.

 * delta-search: fix crash caused by unbound variable
 * sshpeer: fix path when handling invalid url exception
 * subrepo: fix normalizing paths with scheme

= Mercurial 6.7 =

/!\ This release contains a bug causing possible data loss, use 6.7.4 instead.

As usual, a *lot* of patches don't make it to this list.

== New Features ==

 * JSON templates can now use structured diffstat data
 * Support rhg status --rev --rev
 * The index for REVLOGv1 now has a Rust implementation
 * Improved `hg censor`'s output
 * censor: add a command flag to skip the head checks
 * censor: accept multiple revision in a single call
 * usage: add a `usage.repository-role` config
 * branchmap: use mmap for faster revbranchcache loading
 * crecord: enable search hotkeys (issue6834)
 * hg-core: separate timestamp and extra methods
 * annotate: limit output to range of lines
 * unbundle: faster computation of changed heads
 * Large improvements of some of the phases code (23950e39281f)
 * rust-filepatterns: export glob_to_re function

== New Experimental Features ==

 * Introduce `hg admin::chainsaw-update` for automation and *advanced* users

== Bug Fixes ==

 * templatekw: fix inconsistency of diffstat with diff.merge
 * The endless stream of Python 3 cleanups continues
 * Improved setup.py robustness
 * Improved test suite robustness
 * add: don't attempt to add back removed files unless explicitly listed
 * statprof: handle `lineno == None` in more cases
 * rust: fix cargo doc for hg-cpython
 * rust-python-index: don't panic on a corrupted index when calling from Python
 * debugindexstats: handle the lack of Rust support better
 * matchers: use correct method for finding index in vector
 * narrow: strip trailing `/` from manifest dir before matching it
 * cext: fix potential memory leaks of list items appended with PyList_Append
 * doc: document that labels must have a dot in them to have an effect
 * debugformat: fix formatting for compression level
 * obsutil: sort metadata before comparing in geteffectflag()
 * crecord: drop calls to `curses.endwin()`
 * rust-index: don't use mutable borrow for head-diff computation
 * rust-index: don't use mutable borrow to computed filtered heads


== Backwards Compatibility Changes ==

Users of the Rust extensions and/or `rhg` should be aware that the new Rust
index can result in a performance degradation for push/pull on repositories
*not* using `persistent-nodemap` (see `hg help config.format.use-persistent-nodemap`).

If this is something that matters to you, please reach out to us as this is not
an insurmountable obstacle. This is a choice base on the assumption that
there are few people in this situation and our time should be spent on more
pressing matters.

== Internal API Changes ==

 * 62913:498017baa34b "cleanup: remove some code scheduled to be removed after 5.9"
 * 62914:88ef80210d67 "cleanup: drop `dirstate.is_changing_parent` deprecated since 6.5"
 * 62915:591845f89ada "cleanup: drop `path.pushloc` deprecated since 6.5"
 * 62916:d8f65fc72e7b "cleanup: drop deprecated config attribute on the revlog class"
 * 62917:5c9c41273367 "cleanup: turn `pathsuboption` deprecation warning into an error"
 * 62918:7b837fabc990 "cleanup: turn `wrappedfunction` deprecation warning into an error"
 * 62919:eda075d7b2ac "cleanup: turn `wrapfunction` deprecation warning into an error"
 * 62920:c845479fc64d "cleanup: drop the `bytes` compatibility for attribute related function"
 * 63464:dcaa2df1f688 "changelog: never inline changelog"
 * 63465:a93e52f0b6ff "changelog: disallow delayed write on inline changesets"
 * 63825:79cd29d598af "dirstate: make the `transaction` argument of `setbranch` mandatory"

== Miscellaneous ==

 * perf: support --template on perf::phases
 * perf: add a --as-push option to perf::unbundle
 * debug: add a debug::unbundle command that simulate the unbundle from a push
 * Lots of refactorings to prepare for performance improvements and remove tech debt