relnotes/5.3

phases: sparsify phase lists

When the internal and archived phase was added, allphase became a large,
sparsely populated list. This dramatically increased the number of
lookup operations for public relations in `phasecache.phase`. As a first
step, define allphases and related lists explicitly to contain only the
actual phases. Make phasenames a dictionary and create corresponding
dictionaries for mapping phase names back to numbers. Adjust various
list to be sparse as well with the exception of phaseroots and phasesets
members of phasecache. Keep those as a separate step as it involves
changes to the C module.

Differential Revision: https://phab.mercurial-scm.org/D8697

== New Features ==

 * Windows will process hgrc files in %PROGRAMDATA%\Mercurial\hgrc.d.


== New Experimental Features ==


== Bug Fixes  ==

 * The `indent()` template function was documented to not indent empty lines,
   but it still indented the first line even if it was empty. It no longer does
   that.

== Backwards Compatibility Changes ==


== Internal API Changes ==

 * Matcher instances no longer have a `explicitdir` property. Consider
   rewriting your code to use `repo.wvfs.isdir()` and/or
   `ctx.hasdir()` instead. Also, the `traversedir` property is now
   also called when only `explicitdir` used to be called. That may
   mean that you can simply remove the use of `explicitdir` if you
   were already using `traversedir`.

 * The `revlog.nodemap` object have been merged into the `revlog.index` object.
   * `n in revlog.nodemap` becomes `revlog.index.has_node(n)`,
   * `revlog.nodemap[n]` becomes `revlog.index.rev(n)`,
   * `revlog.nodemap.get(n)` becomes `revlog.index.get_rev(n)`.

 * `copies.duplicatecopies()` was renamed to
   `copies.graftcopies()`. Its arguments changed from revision numbers
   to context objects. It also lost its `repo` and `skip` arguments
   (they should no longer be needed).