meson: wire up development environments

The Meson build system is able to wire up development environments. The
intent is to make build artifacts of the project available. This is
typically used to export e.g. paths to linkable libraries, which isn't
all that interesting in our context given that we don't have an official
library interface.

But what we can use this mechanism for is to expose the built Git
executables as well as the build directory. This allows users to play
around with the built Git version in the devenv, and allows them to
execute our test scripts directly with the built distribution.

Wire up this feature, which can then be used via `meson devenv` in the
build directory.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/meson.build b/meson.build
index 4053024dadeb0aafc067784b976ed3bd96171181..ab4f229436d3070de692a24c3a196a79d214b46f 100644 (file)
--- a/meson.build
+++ b/meson.build
@@ -1939,6 +1939,14 @@ configure_file(
   configuration: build_options_config,
 )
 
+# Development environments can be used via `meson devenv -C <builddir>`. This
+# allows you to execute test scripts directly with the built Git version and
+# puts the built version of Git in your PATH.
+devenv = environment()
+devenv.set('GIT_BUILD_DIR', meson.current_build_dir())
+devenv.prepend('PATH', meson.current_build_dir() / 'bin-wrappers')
+meson.add_devenv(devenv)
+
 summary({
   'curl': curl.found(),
   'expat': expat.found(),