xdiff: add a bdiff hunk mode
xdiff generated hunks for the differences (ex. questionmarks in the
`@@ -?,? +?,? @@` part from `diff --git` output). However, bdiff generates
matched hunks instead.
This patch adds a `XDL_EMIT_BDIFFHUNK` flag used by the output function
`xdl_call_hunk_func`. Once set, xdiff will generate bdiff-like hunks
instead. That makes it easier to use xdiff as a drop-in replacement of bdiff.
Note that since `bdiff('', '')` returns `[(0, 0, 0, 0)]`, the shortcut path
`if (xscr)` is removed. I have checked functions called with `xscr` argument
(`xdl_mark_ignorable`, `xdl_call_hunk_func`, `xdl_emit_diff`,
`xdl_free_script`) work just fine with `xscr = NULL`.
Test Plan:
Will be tested in a later patch.
Differential Revision: https://phab.mercurial-scm.org/D2575
syntax: glob
*.elc
*.tmp
*.orig
*.rej
*~
*.mergebackup
*.o
*.so
*.dll
*.exe
*.pyd
*.pyc
*.pyo
*$py.class
*.swp
*.prof
*.zip
\#*\#
.\#*
tests/.coverage*
tests/.testtimes*
tests/.hypothesis
tests/hypothesis-generated
tests/annotated
tests/exceptions
tests/*.err
tests/htmlcov
build
contrib/chg/chg
contrib/hgsh/hgsh
contrib/vagrant/.vagrant
contrib/docker/debian-*
contrib/docker/ubuntu-*
dist
packages
doc/common.txt
doc/*.[0-9]
doc/*.[0-9].txt
doc/*.[0-9].gendoc.txt
doc/*.[0-9].{x,ht}ml
MANIFEST
MANIFEST.in
patches
mercurial/__modulepolicy__.py
mercurial/__version__.py
mercurial/hgpythonlib.h
mercurial.egg-info
.DS_Store
tags
cscope.*
.idea/*
.asv/*
i18n/hg.pot
locale/*/LC_MESSAGES/hg.mo
hgext/__index__.py
rust/target/
# Generated wheels
wheelhouse/
syntax: regexp
^\.pc/
^\.(pydev)?project
# hackable windows distribution additions
^hg-python
^hg.py$