# Mercurial 6.4 (2023-03-23)

## Mercurial 6.4.5 

- re2: fix reporting of availability in `hg debuginstall`
- ui: fix crash in `hg paths` when pulled-delta-reuse-policy is in use
- path: display proper user facing value for pulled-delta-reuse-policy

## Mercurial 6.4.4 

- clonebundles: filter out invalid schemes instead of failing on them
- doc: format argument for date uses strftime format string (issue6818)
- test: make test-contrib-perf.t more robust
- revlog: fix a bug in revlog splitting
- bundles: clarify streaming v2 bundle usage
- delta-find: fix pulled-delta-reuse-policy=forced behavior
- dirstate: fall back to v1 if reading v2 failed
- revlog: avoid possible collision between directory and temporary index

## Mercurial 6.4.3 

- chg: declare environ (issue6812)
- chg: set CHGHG before connecting to command server
- delta-find: never do anything fancy when general delta is off
- delta-find: add a simple safeguard to prevent bad non-general-delta
- debug-delta: add minimal documentation for `devel.bundle-delta` option
- fix: highlight the required configuration and behavior of the fixer tools
- rhg: don't print copy source when --no-status is passed
- rhg: correctly relativize copy source path
- repo-upgrade: write new requirement before upgrading the dirstate
- backup: fix issue when the backup end up in a different directory

## Mercurial 6.4.2 

Exceptional bugfix release due to a corruption bug that happens when using
clonebundles on repositories with large files.

- revlog-split: make sure the self._indexfile attribute is reset (issue6811)


## Mercurial 6.4.1 

- rhg: fix a bug in path encoding
- rhg: don't crash on empty directory names in path_encode, just in case
- commands: correct documentation of hg serve’s --ipv6 options
- run-tests: remove obsolete coverage check and packaging import (issue6805)
- chg: populate CHGHG if not set
- match: sort patterns before compiling them into a regex
- match: match explicit file using a set
- rebase: do not cleanup the working copy when --dry-run is used (issue6802)
- sslutil: set context security level for legacy tls testing (issue6760)



## Mercurial 6.4 

### New Features 

- There is a new internal merge tool called `internal:union-other-first`.
   It works like `internal:union` but add other side on top of local.
- Pullbundles are enabled by default
- delta-find: add a way to control the number of bases tested at the same time
- changelog-v2: add a configuration to disable rank computation
- debug: add an option to display statistic about a bundling operation
- debug: add an option to display statistic about a unbundling operation
- delta-find: add a delta-reuse policy that blindly accepts incoming deltas
- debug: add debug-revlog-stats command
- dirstate: add narrow support to `verify`
- verify: also check dirstate
- commit: add --draft option to use draft phase
- amend: add a --draft option to set phase to draft
- debug: add a config to abort update early
- rhg: implement checkexec to support weird filesystems
- debugshell: allow commands to be specified as a CLI argument
- rhg-files: add support for narrow when specifying a revision
- rust-narrow: enable narrow support for plain `rhg files`

### Bug Fixes 

Aside from the following (unordered) commits which made it through a manual filter, there are a bunch of typing improvements and fixes, removal of deprecated code and general code cleanup.

- lfs: improve an exception message for blob corruption detected on transfer
- revlog: use the user facing filename as the display_id for filelogs
- rust-status: query fs traversal metadata lazily
- shelve: add Shelf.changed_files for resolving changed files in a plugin
- demandimport: ensure lazyloaderex sets loader attributes (issue6725)
- typing: fix a syntax error in mercurial/cext/bdiff.pyi
- cffi: fix a bytes vs str issue on macOS when listing directories
- changelog-v2: fix the docket `struct`
- schemes: fix a broken check for drive letter conflicts
- worker: avoid reading 1 byte at a time from the OS pipe
- rust-narrow: fix loop that never loops
- setup: Ensure target directory exists with building rust extension
- dirstate: invalidate changes when parent-change fails
- dirstate: warn about non-explicitly rolledback parent-change
- dirstate: write dirstate on successful exit of changing_parents context
- largefile: make sure we hold the lock when updating the second dirstate
- dirstate: enforce holding the lock while doing any changes
- run-tests: stop ignoring venv-installed packages
- transaction: run abort callback in all cases
- transaction: quietly rollback if no other changes than temporary files
- debugrebuilddirstate: double check that no transaction is open
- dirstate: do not write an empty dirstate just for backup
- locking: take the `wlock` for the full `hg add` duration
- locking: take the `wlock` for the full `hg remove` duration
- locking: take the `wlock` for the full `hg forget` duration
- locking: take the `wlock` for the full `hg addremove` duration
- locking: grab the wlock before touching the dirstate in `perfdirstatewrite`
- locking: hold the wlock for the full duration of the "keyword demo"
- mq: properly take the wlock during the full qfold operation
- dirstate: invalidate the dirstate change on transaction failure
- status: fix post status writing
- status: fix post status invalidation
- dirstate: avoid transaction backup/restore if we do not hold the lock
- rollback: explicitly skip dirstate rollback when applicable
- dirstate-guard: remove the feature
- dirstate: make `restorebackup` more robust when it is a noop
- dirstate: generalize the dirstate's invalidation on transaction abort
- dirstate: detect potential fishy transaction patterns while changing
- mq: write the dirstate before stripping
- dirstate: explicitly backup the datafile
- localrepo: enforce a clean dirstate when the transaction open
- localrepo: "blindly" do a dirstate backup at the end of the transaction
- dirstate: remove the dedicated backup logic
- rhg: fix a bug in path_encode
- dirstate: invalidate on all exceptions
- large-files: make sure we write newly initialized standin file early
- dirstate: warn if dirty when starting an edition
- dirstate: track that changes are pending in a transaction
- dirstate: distinct transaction callback from largefile
- automv: lock the repository before searching for renames
- dirstate: only reload the dirstate when it may have changed
- dirstate: cleanup the `_map` property cache
- status: invalidate dirstate  on LockError
- dirstate: check that dirstate is clean at the initial context opening
- dirstate: have `running_status` write the dirstate when holding the lock
- dirstate: have `running_status` warn when exiting with a dirty dirstate
- narrow: widden the lock context in `tracking`
- narrow: enforce that narrow spec is written within a transaction
- transaction: no longer explicitly cache phaseroots
- transaction: no longer explicitly cache bookmarks
- transaction: use the standard transaction mechanism to backup branch
- bundlerepo: handle changegroup induced phase movement in the associated method
- bundlerepo: apply phase data stored in the bundle instead of assuming `draft`
- config-item: declare undeclared path suboption
- narrow: read pending file when applicable
- rust: fix building on macOS (issue6801)
- run-tests: fix a crash when using the coverage options
- undo-files: also remove the undo.backupfiles
- undo-files: cleanup backup when cleaning undos
- undo-files: clean existing files up before writing new one
- undo-files: cleanup legacy files when applicable
- dirstate-v2: fix an incorrect handling of readdir errors
- rust: update zstd dependency
- rust: upgrade `rayon` dependency
- dirstate: fix the bug in [status] dealing with committed&ignored directories
- dirstate: fix a potential traceback when in `copy` and `rename`
- histedit: fix diff colors
- cext: fix for PyLong refactoring in CPython 3.12
- py3: fix for Python 3.12 emitting SyntaxWarning on invalid escape sequences
- statprof: with Python 3.12, lineno is (more) often None
- transaction: properly clean up backup file outside of .hg/store/
- transaction: raise on backup restoration error
- revlog: improve the robustness of the splitting process
- debugdeltachain: stop summing the same chain over and over
- url: don't ignore timeout for https connections
- py3: fix for Python 3.12 emitting SyntaxWarning on invalid escape sequences
- tests: accept a test output change in [tests/test-serve.t]
- rust: fix thread cap (for real this time)
- dirstate: try refreshing the changelog when parent are unknown
- hooks: invalidate the repo after the hooks

### Backwards Compatibility Changes 
- rust: upgrade supported Rust toolchain version
- rust: move all crates in the main workspace to edition 2021
- hg-core: upgrade `zstd` dependency
- hg-core: upgrade `clap` dependency
- hg-core: upgrade all remaining dependencies
- hg-cpython: upgrade dependencies
- rhg: upgrade `clap` dependency
- rhg: upgrade the remainder of the dependencies

### Internal API Changes 

- Many APIs around the dirstate have been made much stricter with regards to
   locking and transaction handling
- Some dirstate APIs have been renamed/removed
- In both cases, you should get loud complaints in your tests if you do
   something wrong.

### Miscellaneous 

- pullbundle support no longer requires setting a server-side option,
   providing a .hg/pullbundles.manifest according to the syntax specified in
   'hg help -e clonebundles' is enough.
- debug-delta-find: add a --source option
- delta-find: add debug information about reuse of cached data
- delta-find: set the default candidate chunk size to 10
- attr: vendor 22.1.0
- configitems: add a default value for "merge-tools.xxx.regappend"
- debugrevlog: display total stored information
- emitrevision: if we need to compute a delta on the fly, try p1 or p2 first
- emitrevision: consider ancestors revision to emit as available base
- find-delta: pass the cache-delta usage policy alongside the cache-delta
- delta-find: use a smarter object for snapshot caching
- delta-find: use sets instead of list in the snapshot cache
- delta-find: make sure we only use newer full snapshot as candidate
- delta-find: use a single snapshot cache when applying a group to an object
- bundleoperation: optionnaly record the `remote` that produced the bundle
- bundle: when forcing acceptance of incoming delta also accept snapshot
- bundle: emit full snapshot as is, without doing a redelta
- pathutil: slightly faster path audit in the common case
- merge: don't pay for pathconflicts if there are none
- merge: short-circuit the _checkfs loop upon getting ENOENT
- merge: disable the whole filesystem access loop if [_realfs] is false
- merge: cache the fs checks made during [_checkunknownfiles]
- rust: use `logging_timer` instead of `micro_timer`
- rust: run `cargo clippy`
- makefile: add `cargo clippy` to tests if cargo is available
- heptapod-ci: add `clippy` to the CI
- convert: use a priority queue for sorting commits, to make sorting faster
- delta-find: adjust the default candidate group chunk size
- delta-find: declare the "paths..*:pulled-delta-reuse-policy option
