[polari] app: Add --version CLI option

[Florian Müllner <fmuellner src gnome org>]

commit 9f4d573edff92dcd2922b3a1426da19506d1a2eb
Author: Florian Müllner <fmuellner gnome org>
Date:   Wed Mar 15 12:08:57 2017 +0100

    app: Add --version CLI option
    
    It's sometimes convenient to check the version without running the
    program to open the about dialog, so add support for the standard
    --version option.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=780272

 src/application.js |    9 +++++++++
 1 files changed, 9 insertions(+), 0 deletions(-)
---
diff --git a/src/application.js b/src/application.js
index aad845a..d73f6fe 100644
--- a/src/application.js
+++ b/src/application.js
@@ -43,6 +43,9 @@ const Application = new Lang.Class({
         this.add_main_option('start-client', 0,
                              GLib.OptionFlags.NONE, GLib.OptionArg.NONE,
                              _("Start Telepathy client"), null);
+        this.add_main_option('version', 0,
+                             GLib.OptionFlags.NONE, GLib.OptionArg.NONE,
+                             _("Print version and exit"), null);
         this.connect('handle-local-options', (o, dict) => {
             try {
                 this.register(null);
@@ -56,6 +59,12 @@ const Application = new Lang.Class({
                 return 0;
             }
 
+            v = dict.lookup_value('version', null);
+            if (v && v.get_boolean()) {
+                print("Polari %s".format(pkg.version));
+                return 0;
+            }
+
             return -1;
         });
     },