meson: dist pot file in tarball

Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-ugly/-/merge_requests/69>

meson.build

@@ -268,6 +268,7 @@ if find_program('xgettext', required : get_option('nls')).found()
   subdir('po')
 endif
 subdir('docs')
+subdir('scripts')
 
 # Set release date
 if gst_version_nano == 0

scripts/dist-translations.py

@@ -0,0 +1,42 @@
+#!/usr/bin/env python3
+#
+# Copyright (C) 2020 Tim-Philipp Müller <tim centricular net>
+#
+# This library is free software; you can redistribute it and/or
+# modify it under the terms of the GNU Library General Public
+# License as published by the Free Software Foundation; either
+# version 2 of the License, or (at your option) any later version.
+#
+# This library is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+# Library General Public License for more details.
+#
+# You should have received a copy of the GNU Library General Public
+# License along with this library; if not, write to the
+# Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
+# Boston, MA 02110-1301, USA.
+
+import os
+import subprocess
+import shutil
+import tempfile
+
+if __name__ == "__main__":
+    dist_root = os.environ['MESON_DIST_ROOT']
+    build_root = os.environ['MESON_BUILD_ROOT']
+    source_root = os.environ['MESON_SOURCE_ROOT']
+    pwd = os.environ['PWD']
+    tmpdir = tempfile.gettempdir()
+
+    module = os.path.basename(os.path.normpath(source_root))
+
+    # Generate pot file
+    print('Generating pot file ...')
+    subprocess.run(['ninja', '-C', build_root, module + '-1.0-pot'], check=True)
+
+    # Dist pot file in tarball
+    print('Copying pot file into dist staging directory ...')
+    pot_src = os.path.join(source_root, 'po', module + '-1.0.pot')
+    dist_po_dir = os.path.join(dist_root, 'po')
+    shutil.copy2(pot_src, dist_po_dir)

scripts/meson.build

@@ -0,0 +1,4 @@
+# dist scripts
+if not meson.is_subproject()
+  meson.add_dist_script('dist-translations.py')
+endif