[json-glib: 1/2] Make xgettext optional

[Emmanuele Bassi <ebassi src gnome org>]

commit 31998d84cb241a4c6343c97afc06ee24e60db032
Author: Xavier Claessens <xavier claessens collabora com>
Date:   Sat Oct 27 07:29:40 2018 -0400

    Make xgettext optional
    
    This copies the same logic and option from glib.

 meson.build       | 7 ++++++-
 meson_options.txt | 3 +++
 2 files changed, 9 insertions(+), 1 deletion(-)
---
diff --git a/meson.build b/meson.build
index aeea9cf..f6b72d4 100644
--- a/meson.build
+++ b/meson.build
@@ -152,7 +152,12 @@ python3 = import('python').find_installation()
 gen_installed_test = files('build-aux/gen-installed-test.py')
 
 subdir('json-glib')
-subdir('po')
+
+# xgettext is optional (on Windows for instance)
+if find_program('xgettext', required : get_option('nls')).found()
+  subdir('po')
+endif
+
 subdir('doc')
 
 if not meson.is_subproject()
diff --git a/meson_options.txt b/meson_options.txt
index 068a03f..5a96998 100644
--- a/meson_options.txt
+++ b/meson_options.txt
@@ -10,3 +10,6 @@ option('man',
 option('tests',
        type: 'boolean', value: true,
        description: 'Build the tests')
+option('nls',
+       type: 'feature', value: 'auto', yield: true,
+       description: 'Enable native language support (translations)')