push: rework the computation of fallbackheads to be correct
The previous computation tried to be smart but ended up being wrong. This was
caught by phase movement test while reworking the phase discovery logic to be
faster.
The previous logic was failing to catch case where the pushed set was not based
on a common heads (i.e. when the discovery seemed to have "over discovered"
content, outside the pushed set)
In the following graph, `e` is a common head and we `hg push -r f`. We need to
detect `c` as a fallback heads and we previous failed to do so::
e
|
d f
|/
c
|
b
|
a
The performance impact of the change seems minimal. On the most impacted
repository at hand (mozilla-try), the slowdown seems mostly mixed in the
overall noise `hg push` but seems to be in the hundred of milliseconds order of
magnitude. When using rust, we seems to be a bit faster, probably because we
leverage more accelaratd internals.
I added a couple of performance related common for further investigation later
on.
#!/bin/sh
#
# tcsh_completion_build.sh - script to generate tcsh completion
#
#
# Copyright (C) 2005 TK Soh.
#
# This is free software; you can redistribute it and/or modify it under
# the terms of the GNU General Public License as published by the Free
# Software Foundation; either version 2 of the License, or (at your
# option) any later version.
#
#
# Description
# -----------
# This script generates a tcsh source file to support completion
# of Mercurial commands and options.
#
# Instruction:
# -----------
# Run this script to generate the tcsh source file, and source
# the file to add command completion support for Mercurial.
#
# tcsh% tcsh_completion.sh FILE
# tcsh% source FILE
#
# If FILE is not specified, tcsh_completion will be generated.
#
# Bugs:
# ----
# 1. command specific options are not supported
# 2. hg commands must be specified immediately after 'hg'.
#
tcsh_file=${1-tcsh_completion}
hg_commands=`hg --debug help | \
sed -e '1,/^list of commands:/d' \
-e '/^enabled extensions:/,$d' \
-e '/^additional help topics:/,$d' \
-e '/^ [^ ]/!d; s/[,:]//g;' | \
xargs -n5 | \
sed -e '$!s/$/ \\\\/g; 2,$s/^ */ /g'`
hg_global_options=`hg -v help | \
sed -e '1,/global/d;/^ *-/!d; s/ [^- ].*//' | \
sed -e 's/ *$//; $!s/$/ \\\\/g; 2,$s/^ */ /g'`
hg_version=`hg version | sed -e '1q'`
script_name=`basename $0`
cat > $tcsh_file <<END
#
# tcsh completion for Mercurial
#
# This file has been auto-generated by $script_name for
# $hg_version
#
# Copyright (C) 2005 TK Soh.
#
# This is free software; you can redistribute it and/or modify it under
# the terms of the GNU General Public License as published by the Free
# Software Foundation; either version 2 of the License, or (at your
# option) any later version.
#
complete hg \\
'n/--cwd/d/' 'n/-R/d/' 'n/--repository/d/' \\
'C/-/($hg_global_options)/' \\
'p/1/($hg_commands)/'
END