[gobject-introspection] build: use proper dylib versioning on macOS

[Philip Chimento <pchimento src gnome org>]

commit d08b5019099a6375563ede434d29038e6916256e
Author: Tom Schoonjans <Tom Schoonjans diamond ac uk>
Date:   Tue Sep 10 12:49:04 2019 +0100

    build: use proper dylib versioning on macOS

 girepository/meson.build | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)
---
diff --git a/girepository/meson.build b/girepository/meson.build
index 0183153e..204659fe 100644
--- a/girepository/meson.build
+++ b/girepository/meson.build
@@ -163,6 +163,15 @@ if cc.get_id() != 'msvc'
   ])
 endif
 
+lib_version = '1.0.0'
+lib_version_arr = lib_version.split('.')
+lib_version_major = lib_version_arr[0].to_int()
+lib_version_minor = lib_version_arr[1].to_int()
+lib_version_micro = lib_version_arr[2].to_int()
+
+osx_current = lib_version_major + 1
+lib_osx_version = [osx_current, '@0@.@1@'.format(osx_current, lib_version_minor)]
+
 girepo_lib = shared_library('girepository-1.0',
   sources: girepo_sources,
   include_directories : configinc,
@@ -170,7 +179,8 @@ girepo_lib = shared_library('girepository-1.0',
           custom_c_args,
   dependencies: [glib_dep, gobject_dep, gmodule_dep,
                  gio_dep, girepo_internals_dep],
-  version: '1.0.0',
+  version: lib_version,
+  darwin_versions: lib_osx_version,
   install: true,
 )