Improve tech preview version computation

This did not work on the SDK builder: the version got set to an empty
string. I'm not sure why, but my guess is the command was not executed
from the source root. Meson documentation says the execution directory
is undefined, so let's make sure to get that right, at least.

2 files changed, 16 insertions, 1 deletions

diff --git a/compute-tech-preview-version.sh b/compute-tech-preview-version.sh
new file mode 100755
index 000000000..9db2f77c9
--- /dev/null
+++ b/compute-tech-preview-version.sh
@@ -0,0 +1,10 @@
+#!/bin/sh
+
+# This script is a not-very-elaborate workaround for the fact that Meson's
+# run_command() executes commands in an unspecified directory. All we need to
+# do here is ensure we run git describe in the source directory.
+#
+# It would be nice if we didn't need to use a script for something so simple.
+
+cd $MESON_SOURCE_ROOT
+git describe
diff --git a/meson.build b/meson.build
index 5f861b25c..483363122 100644
--- a/meson.build
+++ b/meson.build
@@ -41,7 +41,12 @@ tech_preview = get_option('tech_preview')
 conf.set10('TECH_PREVIEW', tech_preview)
 
 if tech_preview
-  conf.set_quoted('VERSION', run_command('git', 'describe').stdout().strip())
+  msg = 'Computing Epiphany Tech Preview version: '
+  res = run_command(join_paths(meson.source_root(), 'compute-tech-preview-version.sh'))
+  assert(res.returncode() == 0, msg + 'FAIL (script returned nonzero exit status)')
+  tech_preview_version = res.stdout().strip()
+  message(msg + tech_preview_version)
+  conf.set_quoted('VERSION', tech_preview_version)
 else
   conf.set_quoted('VERSION', meson.project_version())
 endif