bdiff: use Python memory allocator in fixws
Python has its own memory allocation APIs. For allocations
<= 512 bytes, it allocates memory from arenas. This means that
average small allocations don't call the system allocator, which
makes them faster. Also, arena allocations cut down on memory
fragmentation, which can matter for performance in long-running
processes.
Another advantage of using the Python memory allocator is that
allocations are tracked by Python. This is a bigger deal in
Python 3, as modern versions of Python have some decent built-in
tools for examining memory usage, leaks, etc.
This patch converts a trivial malloc() + free() in the bdiff code
to use the Python allocator APIs. Since the object being
operated on is a line, chances are it will use an arena. So,
this could have a net positive impact on performance (although
I didn't measure it).
$ cat > patchtool.py <<EOF
> import sys
> print 'Using custom patch'
> if '--binary' in sys.argv:
> print '--binary found !'
> EOF
$ echo "[ui]" >> $HGRCPATH
$ echo "patch=python ../patchtool.py" >> $HGRCPATH
$ hg init a
$ cd a
$ echo a > a
$ hg commit -Ama -d '1 0'
adding a
$ echo b >> a
$ hg commit -Amb -d '2 0'
$ cd ..
This test checks that:
- custom patch commands with arguments actually work
- patch code does not try to add weird arguments like
--binary when custom patch commands are used. For instance
--binary is added by default under win32.
check custom patch options are honored
$ hg --cwd a export -o ../a.diff tip
$ hg clone -r 0 a b
adding changesets
adding manifests
adding file changes
added 1 changesets with 1 changes to 1 files
updating to branch default
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ hg --cwd b import -v ../a.diff
applying ../a.diff
Using custom patch
applied to working directory
Issue2417: hg import with # comments in description
Prepare source repo and patch:
$ rm $HGRCPATH
$ hg init c
$ cd c
$ printf "a\rc" > a
$ hg ci -A -m 0 a -d '0 0'
$ printf "a\rb\rc" > a
$ cat << eof > log
> first line which can't start with '# '
> # second line is a comment but that shouldn't be a problem.
> A patch marker like this was more problematic even after d7452292f9d3:
> # HG changeset patch
> # User lines looks like this - but it _is_ just a comment
> eof
$ hg ci -l log -d '0 0'
$ hg export -o p 1
$ cd ..
Clone and apply patch:
$ hg clone -r 0 c d
adding changesets
adding manifests
adding file changes
added 1 changesets with 1 changes to 1 files
updating to branch default
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ cd d
$ hg import ../c/p
applying ../c/p
$ hg log -v -r 1
changeset: 1:cd0bde79c428
tag: tip
user: test
date: Thu Jan 01 00:00:00 1970 +0000
files: a
description:
first line which can't start with '# '
# second line is a comment but that shouldn't be a problem.
A patch marker like this was more problematic even after d7452292f9d3:
# HG changeset patch
# User lines looks like this - but it _is_ just a comment
$ cd ..