Adds NOT search operator

src/app/index/query.rs

@@ -54,6 +54,7 @@ pub enum Literal {
 pub enum BoolOp {
 	And,
 	Or,
+	Not,
 }
 
 #[derive(Debug, Eq, PartialEq)]
@@ -128,7 +129,12 @@ pub fn make_parser() -> impl Parser<char, Expr, Error = Simple<char>> {
 		let filter = choice((text_cmp, number_cmp, fuzzy));
 		let atom = choice((filter, expr.delimited_by(just('('), just(')'))));
 
-		let bool_op = choice((just("&&").to(BoolOp::And), just("||").to(BoolOp::Or))).padded();
+		let bool_op = choice((
+			just("&&").to(BoolOp::And),
+			just("||").to(BoolOp::Or),
+			just("!!").to(BoolOp::Not),
+		))
+		.padded();
 
 		let combined = atom
 			.clone()

src/app/index/search.rs

@@ -119,6 +119,8 @@ impl Search {
 		match (left, op, right) {
 			(Some(l), BoolOp::And, Some(r)) => l.intersection(&r).cloned().collect(),
 			(Some(l), BoolOp::Or, Some(r)) => l.union(&r).cloned().collect(),
+			(Some(l), BoolOp::Not, Some(r)) => l.difference(&r).cloned().collect(),
+			(None, BoolOp::Not, _) => IntSet::default(),
 			(Some(l), _, None) => l,
 			(None, _, Some(r)) => r,
 			(None, _, None) => IntSet::default(),
@@ -605,6 +607,28 @@ mod test {
 		assert!(songs.contains(&PathBuf::from("whales in space.mp3")));
 	}
 
+	#[test]
+	fn can_use_not_operator() {
+		let ctx = setup_test(vec![
+			scanner::Song {
+				virtual_path: PathBuf::from("whale.mp3"),
+				..Default::default()
+			},
+			scanner::Song {
+				virtual_path: PathBuf::from("space.mp3"),
+				..Default::default()
+			},
+			scanner::Song {
+				virtual_path: PathBuf::from("whales in space.mp3"),
+				..Default::default()
+			},
+		]);
+
+		let songs = ctx.search("whale !! space");
+		assert_eq!(songs.len(), 1);
+		assert!(songs.contains(&PathBuf::from("whale.mp3")));
+	}
+
 	#[test]
 	fn results_are_sorted() {
 		let ctx = setup_test(vec![