[fractal] Prefer to use `is_empty()`

[Daniel Garcia Moreno <danigm src gnome org>]

commit 37fd93b32f4507ec8c5bbf8bcf17e15846f666b9
Author: Yuki Okushi <huyuumi dev gmail com>
Date:   Thu Aug 13 19:53:25 2020 +0900

    Prefer to use `is_empty()`

 fractal-gtk/src/app/connect/account.rs   | 4 ++--
 fractal-gtk/src/appop/account.rs         | 4 ++--
 fractal-gtk/src/appop/state.rs           | 2 +-
 fractal-gtk/src/widgets/address.rs       | 2 +-
 fractal-gtk/src/widgets/autocomplete.rs  | 2 +-
 fractal-gtk/src/widgets/room_settings.rs | 4 ++--
 6 files changed, 9 insertions(+), 9 deletions(-)
---
diff --git a/fractal-gtk/src/app/connect/account.rs b/fractal-gtk/src/app/connect/account.rs
index c3a7773e..2caea2f9 100644
--- a/fractal-gtk/src/app/connect/account.rs
+++ b/fractal-gtk/src/app/connect/account.rs
@@ -167,7 +167,7 @@ impl App {
                         if new != verify {
                             matching = false;
                         }
-                        if new != "" && verify != "" && old != "" {
+                        if !new.is_empty() && !verify.is_empty() && !old.is_empty() {
                             empty = false;
                         }
                     }
@@ -216,7 +216,7 @@ impl App {
         destruction_entry.connect_property_text_notify(
             clone!(@strong destruction_btn => move |w| {
                 if let Some(text) = w.get_text() {
-                    if text != "" {
+                    if !text.is_empty() {
                         destruction_btn.set_sensitive(true);
                         return;
                     }
diff --git a/fractal-gtk/src/appop/account.rs b/fractal-gtk/src/appop/account.rs
index 136f8f7a..136c0c3c 100644
--- a/fractal-gtk/src/appop/account.rs
+++ b/fractal-gtk/src/appop/account.rs
@@ -104,7 +104,7 @@ impl AppOp {
 
         entry.connect_property_text_notify(move |w| {
             if let Some(text) = w.get_text() {
-                if text != "" {
+                if !text.is_empty() {
                     button.set_sensitive(true);
                     return;
                 }
@@ -682,7 +682,7 @@ impl AppOp {
 
         if let Some(old) = old_password.get_text() {
             if let Some(new) = new_password.get_text() {
-                if old != "" && new != "" {
+                if !old.is_empty() && !new.is_empty() {
                     password_btn.set_sensitive(false);
                     password_btn_stack.set_visible_child_name("spinner");
                     thread::spawn(move || {
diff --git a/fractal-gtk/src/appop/state.rs b/fractal-gtk/src/appop/state.rs
index 019e9bf7..6a062a9b 100644
--- a/fractal-gtk/src/appop/state.rs
+++ b/fractal-gtk/src/appop/state.rs
@@ -69,7 +69,7 @@ impl AppOp {
             _ => "",
         };
 
-        if widget_focus != "" {
+        if !widget_focus.is_empty() {
             self.ui
                 .builder
                 .get_object::<gtk::Widget>(widget_focus)
diff --git a/fractal-gtk/src/widgets/address.rs b/fractal-gtk/src/widgets/address.rs
index 883d229c..d8da0020 100644
--- a/fractal-gtk/src/widgets/address.rs
+++ b/fractal-gtk/src/widgets/address.rs
@@ -137,7 +137,7 @@ impl<'a> Address<'a> {
         let medium = self.medium.clone();
         self.entry.connect_property_text_notify(move |w| {
             if let Some(text) = w.get_text() {
-                if text != "" {
+                if !text.is_empty() {
                     /* FIXME: use better validation */
                     match medium {
                         AddressType::Email => {
diff --git a/fractal-gtk/src/widgets/autocomplete.rs b/fractal-gtk/src/widgets/autocomplete.rs
index 02b1a6e0..697da8ab 100644
--- a/fractal-gtk/src/widgets/autocomplete.rs
+++ b/fractal-gtk/src/widgets/autocomplete.rs
@@ -154,7 +154,7 @@ impl Autocomplete {
                         let end = buffer.get_end_iter();
 
                         match buffer.get_text(&start, &end, false) {
-                            Some(ref t) if t == "" => {
+                            Some(ref t) if t.is_empty() => {
                                 own.borrow_mut().autocomplete_enter();
                             }
                             None => {
diff --git a/fractal-gtk/src/widgets/room_settings.rs b/fractal-gtk/src/widgets/room_settings.rs
index 45410482..fde79787 100644
--- a/fractal-gtk/src/widgets/room_settings.rs
+++ b/fractal-gtk/src/widgets/room_settings.rs
@@ -515,7 +515,7 @@ impl RoomSettings {
         let room = &self.room;
         let old_name = room.name.clone()?;
         let new_name = new_name?;
-        if new_name != "" && new_name != old_name {
+        if !new_name.is_empty() && new_name != old_name {
             return Some(new_name);
         }
 
@@ -526,7 +526,7 @@ impl RoomSettings {
         let room = &self.room;
         let old_name = room.topic.clone()?;
         let new_name = new_name?;
-        if new_name != "" && new_name != old_name {
+        if !new_name.is_empty() && new_name != old_name {
             return Some(new_name);
         }