relnotes/6.3

merge: add a config to allow conflict-free merge of changes on adjacent lines

This change adds a config to make it no longer a conflict to merge changes
made on adjacent lines.

The reason these changes are considered a conflict is that there's no
region of text at the relevant position (sync region) that's kept unchanged
by both sides of the merge.

The problem can be solved by making the sync regions being a bit more
powerful: we can keep a 0-length sync region if we find that
a block unchanged by one side is ajacent to a block unchanged by the
other side.

Since these 0-length sync regions are emitted using the ~same algorithm
as the normal non-empty sync regions, this change involves no arbitrary
decisions and I expect it to work pretty well.

0-length sync regions do create an ambiguity in a special case where two
pairs of adjacent regions "meet" at the same point. This corresponds to
an insertion made at the same place by the two sides of the merge, and
this still results in a conflict.

= Mercurial 6.3.3 =

 * tests: filter out PEP 657 error locations in tracebacks (issue6780)
 * tests: optional PEP 657 error location in test-extension.t (issue6781)
 * tests: optional PEP 657 error location in test-lfs-serve-access.t (issue6782)
 * histedit: byteify the help for the multifold action
 * sparse: fix a py2 based usage of `map()`
 * convert: stop passing str to the dateutil API in darcs
 * convert: turn the last str regex into bytes in cvs.py (issue6789)
 * convert: change socket mode from b'r+' to 'rwb' in cvs.py (issue6789)
 * convert: replace repr() by pycompat.byterepr() in cvsps.py (issue6789)
 * tests: os module is frozen in Python 3.11 (issue6786)
 * hgweb: unbyteify the 100-continue check
 * resourceutil: start using importlib.resources.files() when possible
 * revset: the `random` sort should not depend on sys.maxsize (issue6770)
 * tests: make sure pygments can detect python script without extension
 * convert: brz 3.3.0 moved NoSuchFile exception to breezy.transport
 * tests: pygments 2.14+ highlight whitespace in python code
 * hghave: make different has_pyoxidizer functions have different names
 * hghave: refactor checks for pygments versions using checkvers()
 * rust-narrow: fix loop that never loops
 * scmutil: make checknewlabel() allow "_" in otherwise numeric names (issue6737)
 * bundlerepo: enforce the requirements declared by the underlying repository
 * setup: make the version computation process more resistant
 * fix: add more information to the debug output
 * tag: disallow tagging the working directory
 * dirstate: handle missing backup file on restoration
 * dirstate-v2: complain early on docket name collision
 * rust: upgrade minimum `rayon` dependency
 * setup: support building from an ongoing merge
 * rust: add debug log about skipping dirstate update
 * rust-dirstate: trace append/no append to help debugging
 * dirstate-v2: don't mmap the data file when on NFS
 * run-tests: make it possible to nest conditionals
 * dirstate: add some debug output when writing the dirstate
 * testing: introduce util function to synchronize concurrent commands on files
 * dirstate: add a way to test races happening during status
 * dirstate: use more than a bool to control append behavior
 * dirstate-v2: add devel config option to control write behavior
 * rhg: fix race when a fixup file is deleted on disk
 * rhg: fix race when an ambiguous file is deleted on disk
 * dirstate: deal with read-race for pure python code
 * dirstate: deal with read-race for python code using rust object
 * dirstate: deal with read-race for pure rust code path (rhg)
 * dirstate: set identity whenever we read the dirstate's v2 docket
 * rust-dirstate-v2: don't write dirstate if data file has changed
 * rhg: remember the inode of .hg/dirstate

= Mercurial 6.3.2 =

 * [ecfc84b956a8] tests: expect the message from 1baf0fffd82f in test-hghave.t (issue6762)
 * [5c095119bff4] tests: add the missing space to test-hghave.t (issue6762)
 * [2c346c1c75ec] tests: use an all too familiar executable in test-run-tests.t (issue6661)
 * [13c0e3b4fd35] tests: use `test -f` instead of `ls` to see if a file is present (issue6662)
 * [8ced4ca30ea1] bisect: correct message about aborting an in-progress bisect (issue6527)
 * filemerge: fix crash when using filesets in [partial-merge-tools]
 * help: fix a py3 error interpolating Set into b'%s'
 * match: make the FLAG_RE pattern a raw string
 * python-compat: adapt to Python 3.11 BC breakage with `random.sample`
 * rust-status: fix thread count ceiling
 * hg: show the correct message when cloning an LFS repo with extension disabled
 * extensions: process disabled external paths when `hgext` package is in-memory
 * emitrevision: consider ancestors revision to emit as available base
 * make: add a target for building pyoxidizer tests on macOS
 * run-tests: support --pyoxidized on macOS
 * packaging: add dependencies to the PyOxidizer build on macOS
 * Miscellaneous test fixes

= Mercurial 6.3.1 =

 * memory-usage: fix `hg log --follow --rev R F` space complexity (dcb2581e33be)
 * Improve portability and robustness of test harness
 * hg-core: relax dependencies pinning
 * matcher: fix issues regex flag contained in pattern (issue6759)
 * matcher: do not prepend '.*' to pattern using ^ after flags
 * packaging: refresh dependency hashes (issue6750)
 * cffi: fix a bytes vs str issue on macOS when listing directories
 * commit: properly consider file include and exclude options when closing branch
 * dirstate-v2: do not put the dirstate data file in a transaction

= Mercurial 6.3 =

== New Features ==

 * testlib: add `--raw-sha1` option to `f`
 * rhg: add `config.rhg` helptext
 * config: add alias from `hg help rhg` to `hg help rust`
 * rhg: add a config option to fall back immediately
 * bundle: introduce a --exact option
 * perf-bundle: add a new command to benchmark bundle creation time
 * perf-bundle: accept --rev arguments
 * perf-bundle: accept --type argument
 * perf-unbundle: add a perf command to time the unbundle operation
 * perf: introduce a benchmark for delta-find
 * contrib: add support for rhel9
 * phase-shelve: Implement a 'shelve.store' experimental config
 * debug-delta-find: introduce a quiet mode
 * sort-revset: introduce a `random` variant
 * phase: introduce a dedicated requirement for the `archived` phase
 * rebase: add boolean config item rebase.store-source
 * rhg: make [rhg status -v] work when it needs no extra output
 * rhg: support "!" syntax for disabling extensions
 * rhg: add debugrhgsparse command to help figure out bugs in rhg
 * rhg: add sparse support
 * rhg-status: add support for narrow clones
 * templates: add filter to reverse list
 * contrib: add pull_logger extension
 * revset: handle wdir() in `roots()`
 * revset: handle wdir() in `sort(..., -topo)`
 * rhg: support tweakdefaults
 * rhg: parallellize computation of [unsure_is_modified]

== Default Format Change ==

These changes affect newly created repositories (or new clones) done with
Mercurial 6.3.

== New Experimental Features ==

== Bug Fixes ==

 * shelve: demonstrate that the state is different across platforms (issue6735)
 * shelve: in test for trailing whitespace, strip commit (issue6735)
 * shelve: remove strip and rely on prior state (issue6735)
 * tests: fix http-bad-server expected errors for python 3.10 (issue6643)
 * status: let `--no-copies` override `ui.statuscopies`
 * releasenotes: use re.MULTILINE mode when checking admonitions
 * rhg: fallback to slow path on invalid patterns in hgignore
 * Fix a bunch of leftover str/bytes issues from Python 3 migration
 * keepalive: ensure `close_all()` actually closes all cached connections
 * lfs: fix blob corruption when tranferring with workers on posix
 * lfs: avoid closing connections when the worker doesn't fork
 * dirstate-v2: update constant that wasn't kept in sync
 * dirstate-v2: fix edge case where entries aren't sorted
 * upgrade: no longer keep all revlogs in memory at any point
 * rust-status: save new dircache even if just invalidated
 * dirstate-v2: hash the source of the ignore patterns as well
 * rhg: fallback when encountering ellipsis revisions
 * shelve: handle empty parents and nodestoremove in shelvedstate (issue6748)
 * profile: prevent a crash when line number is unknown
 * tags-fnode-cache: do not repeatedly open the filelog in a loop
 * tags-fnode-cache: skip building a changectx in getfnode
 * rust: create wrapper struct to reduce `regex` contention issues

== Backwards Compatibility Changes ==

 * chg worker processes will now correctly load per-repository configuration
   when given a both a relative `--repository` path and an alternate working
   directory via `--cwd`. A side-effect of this change is that these workers
   will now return an error if hg cannot find the current working directory,
   even when a different directory is specified via `--cwd`.
 * phase: rename the requirement for internal-phase from `internal-phase` to `use-internal-phase` (see 74fb1842f8b962cf03d7cd5b841dbcf2ae065587)

== Internal API Changes ==

== Miscellaneous ==

 * sslutil: use proper attribute to select python 3.7+
 * typing: suppress a few pyi-errors with more recent pytype
 * ci: bump pytype to 2022.03.29
 * bundlespec: add documentation about existing option
 * subrepo: avoid opening console window for non-native subrepos on Windows
 * setup: unconditionally enable the `long-paths-support` option on Windows
 * setup: use the full executable manifest from `python.exe`
 * tests: work around libmagic bug in svn subrepo tests
 * packagelib: use python3 by default
 * Improve `hg bisect` performance
 * perf: properly process formatter option in perf::unbundle
 * compare-disco: miscellaneous display improvements
 * fsmonitor: better compatibility with newer Pythons
 * revlog: finer computation of "issnapshot"
 * rhg: don't fallback if `strip` or `rebase` are activated
 * perf: make perf::bundle compatible before 61ba04693d65
 * perf: make perf::bundle compatible down to 5.2
 * perf-unbundle: improve compatibility
 * run-tests: display the time it took to install Mercurial
 * mergetools: don't let meld open all changed files on startup
 * dirstate-v2: skip evaluation of hgignore regex on cached directories