perf: prefer into_iter() over clone()

src/flatten.rs

@@ -85,7 +85,7 @@ fn get_opened_nothing_opened_is_top_level() {
     let opened = HashSet::new();
     let result = flatten(&opened, &items);
     let result_text = result
-        .iter()
+        .into_iter()
         .map(|flattened| flattened.item.identifier)
         .collect::<Vec<_>>();
     assert_eq!(result_text, ["a", "b", "h"]);
@@ -99,7 +99,7 @@ fn get_opened_wrong_opened_is_only_top_level() {
     opened.insert(vec!["b", "d"]);
     let result = flatten(&opened, &items);
     let result_text = result
-        .iter()
+        .into_iter()
         .map(|flattened| flattened.item.identifier)
         .collect::<Vec<_>>();
     assert_eq!(result_text, ["a", "b", "h"]);
@@ -112,7 +112,7 @@ fn get_opened_one_is_opened() {
     opened.insert(vec!["b"]);
     let result = flatten(&opened, &items);
     let result_text = result
-        .iter()
+        .into_iter()
         .map(|flattened| flattened.item.identifier)
         .collect::<Vec<_>>();
     assert_eq!(result_text, ["a", "b", "c", "d", "g", "h"]);
@@ -126,7 +126,7 @@ fn get_opened_all_opened() {
     opened.insert(vec!["b", "d"]);
     let result = flatten(&opened, &items);
     let result_text = result
-        .iter()
+        .into_iter()
         .map(|flattened| flattened.item.identifier)
         .collect::<Vec<_>>();
     assert_eq!(result_text, ["a", "b", "c", "d", "e", "f", "g", "h"]);

src/state.rs

@@ -112,8 +112,7 @@ where
     pub fn select_first(&mut self, items: &[Item<Identifier>]) -> bool {
         let identifier = items
             .first()
-            .map(|item| vec![item.identifier.clone()])
-            .unwrap_or_default();
+            .map_or(Vec::new(), |item| vec![item.identifier.clone()]);
         self.select(identifier)
     }
 
@@ -123,9 +122,9 @@ where
     pub fn select_last(&mut self, items: &[Item<Identifier>]) -> bool {
         let visible = self.flatten(items);
         let new_identifier = visible
+            .into_iter()
             .last()
-            .map(|flattened| flattened.identifier.clone())
-            .unwrap_or_default();
+            .map_or(Vec::new(), |flattened| flattened.identifier);
         self.select(new_identifier)
     }
 
@@ -138,9 +137,9 @@ where
         let visible = self.flatten(items);
         let new_index = new_index.min(visible.len().saturating_sub(1));
         let new_identifier = visible
-            .get(new_index)
-            .map(|flattened| flattened.identifier.clone())
-            .unwrap_or_default();
+            .into_iter()
+            .nth(new_index)
+            .map_or(Vec::new(), |flattened| flattened.identifier);
         self.select(new_identifier)
     }
 
@@ -178,9 +177,9 @@ where
             .position(|flattened| flattened.identifier == current_identifier);
         let new_index = change_function(current_index).min(visible.len().saturating_sub(1));
         let new_identifier = visible
-            .get(new_index)
-            .map(|flattened| flattened.identifier.clone())
-            .unwrap_or_default();
+            .into_iter()
+            .nth(new_index)
+            .map_or(Vec::new(), |flattened| flattened.identifier);
         self.select(new_identifier)
     }