relnotes/5.4

statprof: separate functions and "line", assume 4 digit line numbers

Previously, the profile output looked like this (I've removed many lines that
are mostly inconsequential):

```
| 100.0%  0.02s  hg:             <module>          line 43:  dispatch.run()
| 100.0%  0.02s  dispatch.py:    run               line 115:  status = dispatch(req)
| 100.0%  0.02s  dispatch.py:    _runcatchfunc     line 432:  return _dispatch(req)
 \ 50.0%  0.01s  dispatch.py:    _dispatch         line 1228:  return runcommand(
   | 50.0%  0.01s  dispatch.py:    runcommand      line 883:  ret = _runcommand(ui, optio...
   | 50.0%  0.01s  dispatch.py:    _runcommand     line 1240:  return cmdfunc()
   | 50.0%  0.01s  localrepo.py:   __getitem__     line 1670:  quick_access = self._quick_...
   | 50.0%  0.01s  localrepo.py:   _quick_access_changeidline 1650:  return self._quick_access_c...
   | 50.0%  0.01s  localrepo.py:   __get__         line 179:  return getattr(unfi, self.n...
   | 50.0%  0.01s  util.py:        __get__         line 1747:  result = self.func(obj)
   | 50.0%  0.01s  localrepo.py:   _quick_access_changeid_wcline  1611:  cl = self.unfiltered().chan...
   | 50.0%  0.01s  localrepo.py:   __get__         line 110:  return super(_basefilecache...
   | 50.0%  0.01s  util.py:        __getattribute__line 245:  self.__spec__.loader.exec_m...
   | 50.0%  0.01s  <frozen importlib._bootstrap_external>: exec_moduleline            783:
   | 50.0%  0.01s  <frozen importlib._bootstrap>: _call_with_frames_removedline                 219:
   | 50.0%  0.01s  changelog.py:   <module>        line 376:  class changelog(revlog.revl...
   | 50.0%  0.01s  util.py:        __getattribute__line 245:  self.__spec__.loader.exec_m...
   | 50.0%  0.01s  <frozen importlib._bootstrap_external>: exec_moduleline            779:
   | 50.0%  0.01s  <frozen importlib._bootstrap_external>: get_codeline         868:
   | 50.0%  0.01s  <frozen importlib._bootstrap_external>: path_statsline           1012:
   | 50.0%  0.01s  <frozen importlib._bootstrap_external>: _path_statline           87:
```

This has a few problems, though I'm only addressing some of them.

1.  If the stuff before "line ###" is long, there's no separation between the
    function name and the "line" string.
2.  If the stuff before "line ###" is really long, there's excessive separation
    between the "line" string and the line number.
3.  We frequently have 4-digit line numbers, the code on the right wasn't
    dynamically indented and ended up quite messy looking.

To solve these problems, I've added a ", " prefix before "line" iff it would
otherwise not have any separation such as spaces. I've added a 'max' so that we
never use a negative width (which is the cause of problem #2 above), and I've
added a default assumption of 4 digit line numbers (but again using a 'max' so
this shouldn't cause problems if we go beyond that.

With these changes, it now looks like this:

```
| 100.0%  0.02s  hg:             <module>          line 43:   dispatch.run()
| 100.0%  0.02s  dispatch.py:    run               line 115:  status = dispatch(req)
| 100.0%  0.02s  dispatch.py:    _runcatchfunc     line 432:  return _dispatch(req)
 \ 50.0%  0.01s  dispatch.py:    _dispatch         line 1228: return runcommand(
   | 50.0%  0.01s  dispatch.py:    runcommand      line 883:  ret = _runcommand(ui, optio...
   | 50.0%  0.01s  dispatch.py:    _runcommand     line 1240: return cmdfunc()
   | 50.0%  0.01s  localrepo.py:   __getitem__     line 1670: quick_access = self._quick_...
   | 50.0%  0.01s  localrepo.py:   _quick_access_changeid, line 1650: return self._quick_access_c...
   | 50.0%  0.01s  localrepo.py:   __get__         line 179:  return getattr(unfi, self.n...
   | 50.0%  0.01s  util.py:        __get__         line 1747: result = self.func(obj)
   | 50.0%  0.01s  localrepo.py:   _quick_access_changeid_wc, line 1611: cl = self.unfiltered().chan...
   | 50.0%  0.01s  localrepo.py:   __get__         line 110:  return super(_basefilecache...
   | 50.0%  0.01s  util.py:        __getattribute__, line 245:  self.__spec__.loader.exec_m...
   | 50.0%  0.01s  <frozen importlib._bootstrap_external>: exec_module, line 783:
   | 50.0%  0.01s  <frozen importlib._bootstrap>: _call_with_frames_removed, line 219:
   | 50.0%  0.01s  changelog.py:   <module>        line 376:  class changelog(revlog.revl...
   | 50.0%  0.01s  util.py:        __getattribute__, line 245:  self.__spec__.loader.exec_m...
   | 50.0%  0.01s  <frozen importlib._bootstrap_external>: exec_module, line 779:
   | 50.0%  0.01s  <frozen importlib._bootstrap_external>: get_code, line 868:
   | 50.0%  0.01s  <frozen importlib._bootstrap_external>: path_stats, line 1012:
   | 50.0%  0.01s  <frozen importlib._bootstrap_external>: _path_stat, line 87:
```

Differential Revision: https://phab.mercurial-scm.org/D9511

== New Features ==

 * `hg purge`/`hg clean` can now delete ignored files instead of
   untracked files, with the new -i flag.

 * `hg pull` now has a `--confirm` flag to prompt before applying changes.
   Config option `pull.confirm` is also added for that.

 * `hg log` now defaults to using an '%' symbol for commits involved
    in unresolved merge conflicts. That includes unresolved conflicts
    caused by e.g. `hg update --merge` and `hg graft`. '@' still takes
    precedence, so what used to be marked '@' still is.

 * New `conflictlocal()` and `conflictother()` revsets return the
   commits that are being merged, when there are conflicts. Also works
   for conflicts caused by e.g. `hg graft`.

 * `hg copy --forget` can be used to unmark a file as copied.

 * The `format.revlog-compression` configuration entry now accept a list. The
   first available option will be used. for example setting::

     [format]
     revlog-compression=zstd, zlib

   Will use `zstd` compression for new repositories is available, and will
   simply fall back to `zlib` if not.

 * `hg debugmergestate` output is now templated, which may be useful
   e.g. for IDEs that want to help the user resolve merge conflicts.


== New Experimental Features ==

 * `hg copy` now supports a `--at-rev` argument to mark files as
   copied in the specified commit. It only works with `--after` for
   now (i.e., it's only useful for marking files copied using non-hg
   `cp` as copied).

 * Use `hg copy --forget --at-rev REV` to unmark already committed
   copies.

== Bug Fixes  ==

 * Fix server exception when concurrent pushes delete the same bookmark

 * Prevent pushes of divergent bookmarks (foo@remote)

 * The push error "remote repository changed while pushing - please
   try again" now only happens when a concurrent push changed related
   heads (instead of when a concurrent pushed any revision).


== Backwards Compatibility Changes ==

 * When `hg rebase` pauses for merge conflict resolution, the working
   copy will no longer have the rebased node as a second parent. You
   can use the new `conflictparents()` revset for finding the other
   parent during a conflict.

 * `hg rebase` now accepts repeated `--source` and `--base`
   arguments. For example, `hg rebase --source 'A + B'` is equivalent
   to `hg rebase --source A --source B`. This is a
   backwards-incompatible change because it will break overriding an
   alias `myrebase = rebase --source A` by `hg myrebase --source B`
   (it will now rebase `(A + B)::` instead of `B::`).

 * `hg recover` does not verify the validity of the whole repository
   anymore. You can pass `--verify` or call `hg verify` if necessary.

 * `hg debugmergestate` output format changed. Let us know if that is
   causing you problems and we'll roll it back.

 * Resolved merge conflicts are now cleared by `hg commit` even if the
   working copy has no changes.


== Internal API Changes ==

 * The deprecated `ui.progress()` has now been deleted. Please use
   `ui.makeprogress()` instead.

 * `hg.merge()` now takes a `ctx` instead of the previous `repo` and
   `node` arguments.

 * `hg.merge()` has lost its `abort` argument. Please call
   `hg.abortmerge()` directly instead.

 * `hg.merge()` has lost its `mergeforce` argument. It should have
   only ever been called with the same value as the `force` argument.

 * The `*others` argument of `cmdutil.check_incompatible_arguments()`
   changed from being varargs argument to being a single collection.