relnotes/5.3

dirstate-v2: Add storage space for nanoseconds precision in file mtimes

For now the sub-second component is always set to zero for tracked files and
symlinks. (The mtime of directories for the `readdir`-skipping optimization
is a different code path and already uses the full precision available.)

This extra storage uses the space previously freed by replacing the 32-bit
`mode` field by two bits in the existing `flags` field, so the overall size
of nodes is unchanged. (This space had been left as padding for this purpose.)

Also move things around in the node layout and documentation to have less
duplication. Now that they have the same representation, directory mtime and
file mtime are kept in the same field. (Only either one can exist for a given
node.)

Differential Revision: https://phab.mercurial-scm.org/D11655

== 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).