dirstate-tree: optimize HashMap lookups with raw_entry_mut
This switches to using `HashMap` from the hashbrown crate,
in order to use its `raw_entry_mut` method.
The standard library’s `HashMap` is also based on this same crate,
but `raw_entry_mut` is not yet stable there:
https://github.com/rust-lang/rust/issues/56167
Using version 0.9 because 0.10 is yanked and 0.11 requires Rust 1.49
This replaces in `DirstateMap::get_or_insert_node` a call to
`HashMap<K, V>::entry` with `K = WithBasename<Cow<'on_disk, HgPath>>`.
`entry` takes and consumes an "owned" `key: K` parameter, in case a new entry
ends up inserted. This key is converted by `to_cow` from a value that borrows
the `'path` lifetime.
When this function is called by `Dirstate::new_v1`, `'path` is in fact
the same as `'on_disk` so `to_cow` can return an owned key that contains
`Cow::Borrowed`.
For other callers, `to_cow` needs to create a `Cow::Owned` and thus make
a costly heap memory allocation. This is wasteful if this key was already
present in the map. Even when inserting a new node this is typically the case
for its ancestor nodes (assuming most directories have numerous descendants).
Differential Revision: https://phab.mercurial-scm.org/D12317
#!/usr/bin/env python3
#
# runrst - register custom roles and run correct writer
#
# Copyright 2010 Olivia Mackall <olivia@selenic.com> and others
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.
"""usage: %s WRITER args...
where WRITER is the name of a Docutils writer such as 'html' or 'manpage'
"""
import sys
try:
import docutils.core as core
import docutils.nodes as nodes
import docutils.utils as utils
import docutils.parsers.rst.roles as roles
except ImportError:
sys.stderr.write(
"abort: couldn't generate documentation: docutils "
"module is missing\n"
)
sys.stderr.write(
"please install python-docutils or see "
"http://docutils.sourceforge.net/\n"
)
sys.exit(-1)
def role_hg(name, rawtext, text, lineno, inliner, options=None, content=None):
text = "hg " + utils.unescape(text)
linktext = nodes.literal(rawtext, text)
parts = text.split()
cmd, args = parts[1], parts[2:]
refuri = "hg.1.html#%s" % cmd
if cmd == 'help' and args:
if args[0] == 'config':
# :hg:`help config`
refuri = "hgrc.5.html"
elif args[0].startswith('config.'):
# :hg:`help config.SECTION...`
refuri = "hgrc.5.html#%s" % args[0].split('.', 2)[1]
elif len(args) >= 2 and args[0] == '-c':
# :hg:`help -c COMMAND ...` is equivalent to :hg:`COMMAND`
# (mainly for :hg:`help -c config`)
refuri = "hg.1.html#%s" % args[1]
else:
refuri = "hg.1.html#%s" % args[0]
node = nodes.reference(rawtext, '', linktext, refuri=refuri)
return [node], []
roles.register_local_role("hg", role_hg)
if __name__ == "__main__":
if len(sys.argv) < 2:
sys.stderr.write(__doc__ % sys.argv[0])
sys.exit(1)
writer = sys.argv[1]
del sys.argv[1]
core.publish_cmdline(writer_name=writer)