Source build recipes: Unable to use upstream version number

[James Ascroft-Leigh]

Feature request:

When building "vanilla" packages from upstream it would be useful to be able to provide the version number for the new package later in the build process. For example for the wkhtmltopdf package, the version number upstream seems to come from this file:

http://github.com/antialize/wkhtmltopdf/blob/master/version.pri

Which currently looks like this:

MAJOR_VERSION=0
MINOR_VERSION=10
PATCH_VERSION=0
BUILD="beta5"

So I would like my PPA package to be numbered as 0.10.0~beta5-auto{time} for now. If upstream them commit a change to this file I'd like the next daily package to reflect the new upstream version number. This could be worked around by allowing the "run" instruction in recipes. Presumably if launchpad has infrastructure for safely building binary packages, it could use the same sandbox for safely building source packages.

Ideally the determination of the final binary package number would be delayed until at least the build dependencies are installed. This would allow me to use qmake to properly extract the version number parameters. My current "run" script has to make use of an ad-hoc parser and python's json module instead!

The recipe that I was unable to use:

# bzr-builder format 0.2 deb-version {debupstream}-autobuild{time}
lp:~jwal/wkhtmltopdf/master git-v1:8cec84731c7ff3c98aab802d11a8650d76e0799e
merge packaging lp:~jwal/wkhtmltopdf/minimal-packaging jascroftleigh@lucid-20100919165644-6483kwbo2xl7nyzb
run python debian/guess-version-number.py