Fix clippy::println_empty_string, clippy::while_let_on_iterator, clippy::while_let_on_iterator lint style violations (#36613)

Related: #36577

Release Notes:

- N/A

crates/editor/src/display_map/block_map.rs

@@ -3183,9 +3183,9 @@ mod tests {
             // so we special case row 0 to assume a leading '\n'.
             //
             // Linehood is the birthright of strings.
-            let mut input_text_lines = input_text.split('\n').enumerate().peekable();
+            let input_text_lines = input_text.split('\n').enumerate().peekable();
             let mut block_row = 0;
-            while let Some((wrap_row, input_line)) = input_text_lines.next() {
+            for (wrap_row, input_line) in input_text_lines {
                 let wrap_row = wrap_row as u32;
                 let multibuffer_row = wraps_snapshot
                     .to_point(WrapPoint::new(wrap_row, 0), Bias::Left)

crates/editor/src/editor.rs

@@ -11021,7 +11021,7 @@ impl Editor {
                 let mut col = 0;
                 let mut changed = false;
 
-                while let Some(ch) = chars.next() {
+                for ch in chars.by_ref() {
                     match ch {
                         ' ' => {
                             reindented_line.push(' ');
@@ -11077,7 +11077,7 @@ impl Editor {
                 let mut first_non_indent_char = None;
                 let mut changed = false;
 
-                while let Some(ch) = chars.next() {
+                for ch in chars.by_ref() {
                     match ch {
                         ' ' => {
                             // Keep track of spaces. Append \t when we reach tab_size

crates/editor/src/indent_guides.rs

@@ -164,8 +164,8 @@ pub fn indent_guides_in_range(
     let end_anchor = snapshot.buffer_snapshot.anchor_after(end_offset);
 
     let mut fold_ranges = Vec::<Range<Point>>::new();
-    let mut folds = snapshot.folds_in_range(start_offset..end_offset).peekable();
-    while let Some(fold) = folds.next() {
+    let folds = snapshot.folds_in_range(start_offset..end_offset).peekable();
+    for fold in folds {
         let start = fold.range.start.to_point(&snapshot.buffer_snapshot);
         let end = fold.range.end.to_point(&snapshot.buffer_snapshot);
         if let Some(last_range) = fold_ranges.last_mut()

crates/editor/src/items.rs

@@ -103,9 +103,9 @@ impl FollowableItem for Editor {
                         multibuffer = MultiBuffer::new(project.read(cx).capability());
                         let mut sorted_excerpts = state.excerpts.clone();
                         sorted_excerpts.sort_by_key(|e| e.id);
-                        let mut sorted_excerpts = sorted_excerpts.into_iter().peekable();
+                        let sorted_excerpts = sorted_excerpts.into_iter().peekable();
 
-                        while let Some(excerpt) = sorted_excerpts.next() {
+                        for excerpt in sorted_excerpts {
                             let Ok(buffer_id) = BufferId::new(excerpt.buffer_id) else {
                                 continue;
                             };