Make desktop notifications feature (dbus) optional

With this I can make a statically linked executable with

    $ cargo build --target=x86_64-unknown-linux-musl \
        --no-default-features --features tls-rustls

The generated executable does not support generating desktop
notifications and uses rustls instead of libssl.

(#65)

libtiny_tui/Cargo.toml

@@ -4,12 +4,16 @@ version = "0.1.0"
 description = "A terminal UI for tiny"
 edition = "2018"
 
+[features]
+default = ["desktop-notifications"]
+desktop-notifications = ["notify-rust"]
+
 [dependencies]
 env_logger = "0.7"
 futures = "0.3.1"
 libtiny_ui = { path = "../libtiny_ui" }
 log = "0.4"
-notify-rust = "3"
+notify-rust = { version = "3", optional = true }
 serde = { version = "1.0.8", features = ["derive"] }
 serde_yaml = "0.7.1"
 tempfile = "3.0.3"

libtiny_tui/src/notifier.rs

@@ -1,4 +1,6 @@
 use crate::{utils::remove_irc_control_chars, MsgTarget};
+
+#[cfg(feature = "desktop-notifications")]
 use notify_rust::Notification;
 
 /// Destktop notification handler
@@ -12,11 +14,15 @@ pub(crate) enum Notifier {
     Messages,
 }
 
+#[cfg(feature = "desktop-notifications")]
 fn notify(summary: &str, body: &str) {
     // TODO: Report errors somehow
     let _ = Notification::new().summary(summary).body(body).show();
 }
 
+#[cfg(not(feature = "desktop-notifications"))]
+fn notify(_summary: &str, _body: &str) {}
+
 impl Notifier {
     pub(crate) fn notify_privmsg(
         &mut self,

tiny/Cargo.toml

@@ -9,17 +9,18 @@ description = "An IRC client"
 edition = "2018"
 
 [features]
-default = ["tls-native"]
+default = ["tls-native", "desktop-notifications"]
 tls-native = ["libtiny_client/tls-native"]
 tls-rustls = ["libtiny_client/tls-rustls"]
+desktop-notifications = ["libtiny_tui/desktop-notifications"]
 
 [dependencies]
 dirs = "1.0.2"
 env_logger = "0.7"
 futures = "0.3.1"
 libtiny_client = { path = "../libtiny_client", default-features = false }
 libtiny_logger = { path = "../libtiny_logger" }
-libtiny_tui = { path = "../libtiny_tui" }
+libtiny_tui = { path = "../libtiny_tui", default-features = false }
 libtiny_ui = { path = "../libtiny_ui" }
 libtiny_wire = { path = "../libtiny_wire" }
 log = "0.4"