Introduce error handling

src/error.rs

@@ -0,0 +1,31 @@
+use std :: { * , any :: * , future :: * } ;
+
+
+
+# [ derive (Debug) ] pub enum ZoodexError {
+	CollectionFileError ,
+}
+
+pub type Result <Success> = result :: Result < Success , ZoodexError > ;
+
+impl From < Box < dyn Any + Send > > for ZoodexError {
+	fn from ( error : Box < dyn Any + Send > ) -> Self {
+		* error . downcast () . unwrap ()
+	}
+}
+
+pub async fn async_result_context <
+	AsyncFunction : Future < Output = Result <Success> > ,
+	SuccessHandler : Fn (Success) ,
+	FailureHandler : Fn (ZoodexError) ,
+	Success ,
+> (
+	function : AsyncFunction ,
+	on_success : SuccessHandler ,
+	on_failure : FailureHandler ,
+) {
+	match function . await {
+		Ok (value) => on_success (value) ,
+		Err (error) => on_failure (error) ,
+	} ;
+}

src/main.rs

@@ -1,4 +1,5 @@
 mod collection ;
+mod error ;
 mod persistence ;
 mod ui ;
 mod utility ;
@@ -8,7 +9,7 @@ use {
 	libadwaita :: { * , prelude :: * } ,
 } ;
 
-use crate :: { persistence :: * , ui :: * } ;
+use crate :: { error :: * , persistence :: * , ui :: * } ;
 
 
 
@@ -25,10 +26,14 @@ fn on_activate ( app : & Application ) {
 	ui . show_window () ;
 
 	spawn_future_local ( async move {
-		let collection = spawn_blocking ( ||
-			read_collection_file () . unwrap ()
-		) . await . unwrap () ;
-
+		async_result_context ( async {
+			let collection = spawn_blocking ( || read_collection_file () )
+				. await ? ? ;
 			ui . render_collection (collection) ;
+
+			Ok (())
+		} , |_| () , |error| {
+			ui . close_window () ;
+		} ) . await ;
 	} ) ;
 }

src/persistence.rs

@@ -1,6 +1,6 @@
-use { fallible_iterator :: * , rusqlite :: * } ;
+use { fallible_iterator :: * , rusqlite :: { Connection , Error :: * } } ;
 
-use crate :: collection :: * ;
+use crate :: { collection :: * , error :: { * , ZoodexError :: * } } ;
 
 
 
@@ -49,3 +49,12 @@ pub fn read_collection_file () -> Result <Collection> {
 		series : series . collect () ? ,
 	} )
 }
+
+impl From < rusqlite :: Error > for ZoodexError {
+	fn from ( error : rusqlite :: Error ) -> Self {
+		match error {
+			SqliteFailure ( _ , _ ) => CollectionFileError ,
+			_ => panic ! () ,
+		}
+	}
+}

src/ui/mod.rs

@@ -48,6 +48,8 @@ impl UI {
 
 	pub fn show_window ( & self ) { self . window . set_visible (true) }
 
+	pub fn close_window ( & self ) { self . window . close () }
+
 	pub fn render_collection ( & self , collection : Collection ) {
 		self . films_component . set_films ( collection . films ) ;
 		self . series_component . set_series ( collection . series ) ;