contrib/Makefile.python

extdiff: allow a preconfigured merge-tool to be invoked

There are three ways to configure an extdiff tool:

    1) cmd.tool = (/path/to/exe optional)
    2) tool = (path/to/exe optional)
    3) tool = sometool someargs

Previously, if no executable is specified in the first two forms, the named tool
must be in $PATH, or the invocation fails.  Since the [merge-tools] section
already has the path to the diff executable, and/or the registry keys to find
the executable on Windows, reuse that configuration for forms 1 and 2 instead of
failing.  We already fallback to [diff-tools] and then [merge-tools] for program
arguments if they aren't specified in the [extdiff] section.

Since this additional lookup only occurs if an executable is not on the $PATH
for the named tool, this is backwards compatible.  For now, we assume the user
knows what he is doing if a path is provided.

This change allows a configuration file like this (assuming beyondcompare3 is
configured in merge-tools), instead of hardcoding system specific a path:

    [extdiff]
    beyondcompare3 =

PYTHONVER=2.7.8
PYTHONNAME=python-
PREFIX=$(HOME)/bin/prefix-$(PYTHONNAME)$(PYTHONVER)
SYMLINKDIR=$(HOME)/bin

help:
	@echo
	@echo 'Make a custom installation of a Python version'
	@echo
	@echo 'Common make parameters:'
	@echo '  PYTHONVER=...    [$(PYTHONVER)]'
	@echo '  PREFIX=...       [$(PREFIX)]'
	@echo '  SYMLINKDIR=...   [$(SYMLINKDIR) creating $(PYTHONNAME)$(PYTHONVER)]'
	@echo
	@echo 'Common make targets:'
	@echo '  python    - install Python $$PYTHONVER in $$PREFIX'
	@echo '  symlink   - create a $$SYMLINKDIR/$(PYTHONNAME)$$PYTHONVER symlink'
	@echo
	@echo 'Example: create a temporary Python installation:'
	@echo '  $$ make -f Makefile.python python PYTHONVER=2.4 PREFIX=/tmp/p24'
	@echo '  $$ /tmp/p24/bin/python -V'
	@echo '  Python 2.4'
	@echo
	@echo 'Some external libraries are required for building Python: zlib bzip2 openssl.'
	@echo 'Make sure their development packages are installed systemwide.'
# fedora: yum install zlib-devel bzip2-devel openssl-devel
# debian: apt-get install zlib1g-dev libbz2-dev libssl-dev
	@echo
	@echo 'To build a nice collection of interesting Python versions:'
	@echo '  $$ for v in 2.{4{,.2,.3},5{,.6},6{,.1,.2,.9},7{,.8}}; do'
	@echo '    make -f Makefile.python symlink PYTHONVER=$$v || break; done'
	@echo 'To run a Mercurial test on all these Python versions:'
	@echo '  $$ for py in `cd ~/bin && ls $(PYTHONNAME)2.*`; do'
	@echo '    echo $$py; $$py run-tests.py test-http.t; echo; done'
	@echo

export LANGUAGE=C
export LC_ALL=C

python: $(PREFIX)/bin/python docutils
	printf 'import sys, zlib, bz2, docutils\nif sys.version_info >= (2,6):\n import ssl' | $(PREFIX)/bin/python

PYTHON_SRCDIR=Python-$(PYTHONVER)
PYTHON_SRCFILE=$(PYTHON_SRCDIR).tgz

$(PREFIX)/bin/python:
	[ -f $(PYTHON_SRCFILE) ] || wget http://www.python.org/ftp/python/$(PYTHONVER)/$(PYTHON_SRCFILE) || [ -f $(PYTHON_SRCFILE) ]
	rm -rf $(PYTHON_SRCDIR)
	tar xf $(PYTHON_SRCFILE)
	# Ubuntu disables SSLv2 the hard way, disable it on old Pythons too
	-sed -i 's,self.*SSLv2_method(),0;//\0,g' $(PYTHON_SRCDIR)/Modules/_ssl.c
	# Find multiarch system libraries on Ubuntu with Python 2.4.x
	# http://lipyrary.blogspot.dk/2011/05/how-to-compile-python-on-ubuntu-1104.html
	-sed -i "s|lib_dirs = .* \[|\0'/usr/lib/`dpkg-architecture -qDEB_HOST_MULTIARCH`',|g" $(PYTHON_SRCDIR)/setup.py
	# Find multiarch system libraries on Ubuntu and disable fortify error when setting argv
	LDFLAGS="-L/usr/lib/`dpkg-architecture -qDEB_HOST_MULTIARCH`"; \
	BASECFLAGS=-U_FORTIFY_SOURCE; \
	export LDFLAGS BASECFLAGS; \
	cd $(PYTHON_SRCDIR) && ./configure --prefix=$(PREFIX) && make all SVNVERSION=pwd && make install
	printf 'import sys, zlib, bz2\nif sys.version_info >= (2,6):\n import ssl' | $(PREFIX)/bin/python
	rm -rf $(PYTHON_SRCDIR)

DOCUTILSVER=0.12
DOCUTILS_SRCDIR=docutils-$(DOCUTILSVER)
DOCUTILS_SRCFILE=$(DOCUTILS_SRCDIR).tar.gz

docutils: $(PREFIX)/bin/python
	@$(PREFIX)/bin/python -c 'import docutils' || ( set -ex; \
	[ -f $(DOCUTILS_SRCFILE) ] || wget http://downloads.sourceforge.net/project/docutils/docutils/$(DOCUTILSVER)/$(DOCUTILS_SRCFILE) || [ -f $(DOCUTILS_SRCFILE) ]; \
	rm -rf $(DOCUTILS_SRCDIR); \
	tar xf $(DOCUTILS_SRCFILE); \
	cd $(DOCUTILS_SRCDIR) && $(PREFIX)/bin/python setup.py install --prefix=$(PREFIX); \
	$(PREFIX)/bin/python -c 'import docutils'; \
	rm -rf $(DOCUTILS_SRCDIR); )

symlink: python $(SYMLINKDIR)
	ln -sf $(PREFIX)/bin/python $(SYMLINKDIR)/$(PYTHONNAME)$(PYTHONVER)

.PHONY: help python docutils symlink