Creating releases

In addition to development, almost all projects provide periodical source releases. These are standalone packages (usually either in tar or zip format) of the source code. They do not contain any revision control metadata, only the source code. Meson provides a simple way of generating these, with the meson dist command.

Meson provides a simple way of generating these. It consists of a single command (available since 0.52.0):

meson dist

or alternatively (on older Meson versions with ninja backend):

ninja dist

This creates a file called projectname-version.tar.xz in the build tree subdirectory meson-dist. This archive contains the full contents of the latest commit in revision control including all the submodules (recursively). All revision control metadata is removed. Meson then takes this archive and tests that it works by doing a full compile + test + install cycle. If all these pass, Meson will then create a SHA-256 checksum file next to the archive.

Modifying the dist directory before creating the archive

Modification to the checked out files like generating files or setting version info can be done with dist scripts:

meson.add_dist_script('distscript.sh')

Autotools dist VS Meson dist

Meson behaviour is different from Autotools. The Autotools "dist" target packages up the current source tree. Meson packages the latest revision control commit. The reason for this is that it prevents developers from doing accidental releases where the distributed archive does not match any commit in revision control (especially the one tagged for the release).

Include subprojects in your release

The meson dist command has --include-subprojects command line option. When enabled, the source tree of all subprojects used by the current build will also be included in the final tarball. This is useful to distribute self contained tarball that can be built offline (i.e. --wrap-mode=nodownload).

Skip build and test with --no-tests

The meson dist command has a --no-tests option to skip build and tests steps of generated packages. It can be used to not waste time for example when done in CI that already does its own testing.

So with --no-tests you can tell Meson "Do not build and test generated packages.".

Use --allow-dirty to override error when git repository contains uncommitted changes

Since 0.62.0 Instead of emitting a warning when a repository contains uncommitted changes, Meson will produce an error message notifying the user and immediately exit. If --allow-dirty is given as an option to meson dist, a warning will be emitted instead and Meson will proceed as usual.

Release a subproject separately

Since 0.57.0 the meson dist command can now create a distribution tarball for a subproject in the same git repository as the main project. This can be useful if parts of the project (e.g. libraries) can be built and distributed separately. In that case they can be moved into subprojects/mysub and running meson dist in that directory will now create a tarball containing only the source code from that subdir and not the rest of the main project or other subprojects.

For example:

git clone https://github.com/myproject
cd myproject/subprojects/mysubproject
meson setup builddir
meson dist -C builddir

This produces builddir/meson-dist/mysubproject-1.0.tar.xz tarball.

Cement a version obtained from VCS

Since 1.4.0 the meson dist command enables rewriting the build configuration of the distribution tarball. This is needed when the configuration depends on metadata from revision control such as in the following example.

meson.build:

project('tig', 'c',
  version : run_command('version.sh', 'get-vcs').stdout().strip())

meson.add_dist_script('version.sh', 'set-dist', meson.project_version())

version.sh:

#!/bin/sh

if [ "$1" = "get-vcs" ]; then
  git -C "$MESON_SOURCE_ROOT" describe --always --dirty
elif [ "$1" = "set-dist" ]; then
  $MESONREWRITE --sourcedir="$MESON_PROJECT_DIST_ROOT" kwargs set project / version "$2"
else
  exit 1
fi