git version

[elmarco]

Many projects rely on git generated version. git itself, and there is the popular http://git.savannah.gnu.org/cgit/autoconf.git/tree/build-aux/git-version-gen for autoconf. Other projects use similar scripts.

It would be great if meson had a 'git-version-gen' option in project()

[jpakkane]

This should do what you need.

[elmarco]

Interesting, but how does that help to specify the project version?

[jpakkane]

It can't. Project versions must be written by hand and be explicit. It must also work when Git is not installed. The common approach is to have a sensible version number in project and put the git hash in config.h or similar so you have access to both.

[elmarco]

It's not the same though, git-version-gen allows to generate incremental version for each commit, and avoid having hard-coded version duplication. It's not simply about the git hash.

[nirbheek]

I'm not sure I understand how that's not covered by the vcs_tag command. git commit ids change as soon as you do a rebase or any operation that rewrites history. Even cherry-pick rewrites the commit id. Could you please explain your use-case a bit more? What sort of versions does git-version-gen generate? How are they incremental?

[tp-m]

By default vcs_tag will output something using git describe such as 0.33.0-22-g58359c8 which basically means 22 commits after the 0.33.0 tag, with head at commit 5835...

[elmarco]

What is project() version used for? According to reference manual, it's just for later reference with meson.project_version(), but if you use vcs_tag you'll probably not use it.

Similarly what is the project name for? I can't even find a 'dist' target.

Is there a way to list available targets?

Btw, it would be quite helpeful if the reference manual had function declarations: project(project_name, language1, language2 ...)
optional keywords: version, subproject_dir, meson_version, default_options

Meson is quite confusing when coming from autofoo or even plain Makefile, and documentation has a lot to be desired.

A guess a more complete hello-world project (not just http://mesonbuild.com/samples.html or test cases in meson.git), including binary, static library, shared library, tests.. would help a lot.

[elmarco]

I wish there would be a meson version of GNU hello: http://git.savannah.gnu.org/cgit/hello.git

[jpakkane]

Project versions are used when importing subprojects. They allow you you specify version limits similar to dependency like this:

foo_sp = subproject('foo', version : '>=1.0.0')

The wiki has a more in-depth tutorial, which should be what you want.

The function declarations thing is a known issue. Unfortunately Github's wiki formatting is limited so it is hard to make it look similar to e.g. gtk-doc output.

[nirbheek]

Is there anything else you need here, @elmarco?

[elmarco]

@nirbheek I haven't tried recently, and I have not good knowledge of meson. Afaik, it's not possible to let the version be generated from git describe, like git-version-gen does.

[elmarco]

It's almost possible to use an approach similar to git-version-gen, since you should be able to run_command() like that:

version: run_command(['git-version-gen',
                      '$MESON_SOURCE_ROOT/.tarball_version']).stdout()

However, there is no easy way I can think of to ship .tarball_version... That file should be generated at dist time, and not kept in the build directory after dist, but should be included in dist.

[smcv]

However, there is no easy way I can think of to ship .tarball_version...

Resolving #2166 would provide one, I think?