Generalize common_prefix for AsStr inputs.

Signed-off-by: Jason Volk <jason@zemos.net>

src/core/utils/string.rs

@@ -93,15 +93,19 @@ where
 /// ```
 #[must_use]
 #[allow(clippy::string_slice)]
-pub fn common_prefix<'a>(choice: &'a [&str]) -> &'a str {
+pub fn common_prefix<T: AsRef<str>>(choice: &[T]) -> &str {
 	choice.first().map_or(EMPTY, move |best| {
-		choice.iter().skip(1).fold(*best, |best, choice| {
-			&best[0..choice
-				.char_indices()
-				.zip(best.char_indices())
-				.take_while(|&(a, b)| a == b)
-				.count()]
-		})
+		choice
+			.iter()
+			.skip(1)
+			.fold(best.as_ref(), |best, choice| {
+				&best[0..choice
+					.as_ref()
+					.char_indices()
+					.zip(best.char_indices())
+					.take_while(|&(a, b)| a == b)
+					.count()]
+			})
 	})
 }
 

src/core/utils/string/tests.rs

@@ -16,7 +16,7 @@ fn common_prefix_empty() {
 
 #[test]
 fn common_prefix_none() {
-	let input = [];
+	let input: [&str; 0] = [];
 	let output = super::common_prefix(&input);
 	assert_eq!(output, "");
 }