[gnome-tour] Fix missing translatable strings

[Bilal Elmoussaoui <bilelmoussaoui src gnome org>]

commit e4e9163df24e1da976d759fc8dd5ca1bd669d479
Author: Bilal Elmoussaoui <bil elmoussaoui gmail com>
Date:   Tue Aug 18 18:59:27 2020 +0200

    Fix missing translatable strings
    
    closes #19

 data/resources.gresource.xml | 1 -
 po/meson.build               | 8 +++++++-
 src/utils.rs                 | 2 +-
 src/widgets/pages/welcome.rs | 5 +++--
 src/widgets/window.rs        | 5 +++--
 5 files changed, 14 insertions(+), 7 deletions(-)
---
diff --git a/data/resources.gresource.xml b/data/resources.gresource.xml
index 19c7242..688446a 100644
--- a/data/resources.gresource.xml
+++ b/data/resources.gresource.xml
@@ -2,7 +2,6 @@
 <gresources>
   <gresource prefix="/org/gnome/Tour/">
       <file compressed="true" alias="style.css">resources/style.css</file>
-      <file alias="welcome.mp4">resources/assets/welcome.mp4</file>
       <file compressed="true" alias="activities.svg">resources/assets/activities.svg</file>
       <file compressed="true" alias="calendar.svg">resources/assets/calendar.svg</file>
       <file compressed="true" alias="search.svg">resources/assets/search.svg</file>
diff --git a/po/meson.build b/po/meson.build
index 57d1266..bfc35fd 100644
--- a/po/meson.build
+++ b/po/meson.build
@@ -1 +1,7 @@
-i18n.gettext(gettext_package, preset: 'glib')
+i18n.gettext(
+  gettext_package,
+  args: [
+    '--keyword=i18n_f'
+  ],
+  preset: 'glib'
+)
diff --git a/src/utils.rs b/src/utils.rs
index e47f286..c3eb8fe 100644
--- a/src/utils.rs
+++ b/src/utils.rs
@@ -17,7 +17,7 @@ where
 pub fn i18n_f(format: &str, args: &[&str]) -> String {
     let s = gettext(format);
     let mut parts = s.split("{}");
-    let mut output = parts.next().unwrap_or("").to_string();
+    let mut output = parts.next().unwrap_or_default().to_string();
     for (p, a) in parts.zip(args.iter()) {
         output += &(a.to_string() + &p.to_string());
     }
diff --git a/src/widgets/pages/welcome.rs b/src/widgets/pages/welcome.rs
index 82f58fe..53b4f4b 100644
--- a/src/widgets/pages/welcome.rs
+++ b/src/widgets/pages/welcome.rs
@@ -1,5 +1,6 @@
 #[cfg(feature = "video")]
 use crate::config;
+use crate::utils::i18n_f;
 use gettextrs::gettext;
 #[cfg(feature = "video")]
 use gio::FileExt;
@@ -140,8 +141,8 @@ impl WelcomePageWidget {
 
         let name = glib::get_os_info("NAME").unwrap_or_else(|| "GNOME".into());
         let version = glib::get_os_info("VERSION").unwrap_or_else(|| "3.36".into());
-
-        let title = gtk::Label::new(Some(&gettext(format!("Welcome to {} {}", name, version))));
+        // Translators: The following string is formated as "Welcome to GNOME 3.36" for example
+        let title = gtk::Label::new(Some(&i18n_f("Welcome to {} {}", &[&name, &version])));
         title.set_margin_top(36);
         title.get_style_context().add_class("large-title");
         title.show();
diff --git a/src/widgets/window.rs b/src/widgets/window.rs
index b42d193..91902e3 100644
--- a/src/widgets/window.rs
+++ b/src/widgets/window.rs
@@ -1,4 +1,4 @@
-use crate::utils;
+use crate::utils::i18n_f;
 use gettextrs::gettext;
 use gtk::prelude::*;
 use std::cell::RefCell;
@@ -97,7 +97,8 @@ impl Window {
         let name = glib::get_os_info("NAME").unwrap_or_else(|| "GNOME".into());
         let last_page = ImagePageWidget::new(
             "/org/gnome/Tour/ready-to-go.svg",
-            utils::i18n_f("That's it! We hope that you enjoy {}.", &[&name]),
+            // Translators: The following string is formated as "We hope that you enjoy GNOME"
+            i18n_f("That's it! We hope that you enjoy {}.", &[&name]),
             gettext("To get more advice and tips, see the Help app."),
         );
         last_page.widget.get_style_context().add_class("last-page");