Enable clippy::useless_conversion (#8767)

This PR enables the
[`clippy::useless_conversion`](https://rust-lang.github.io/rust-clippy/master/index.html#/useless_conversion)
rule and fixes the outstanding violations.

Release Notes:

- N/A

crates/editor/src/display_map.rs

@@ -502,7 +502,7 @@ impl DisplaySnapshot {
 
     /// Returns text chunks starting at the end of the given display row in reverse until the start of the file
     pub fn reverse_text_chunks(&self, display_row: u32) -> impl Iterator<Item = &str> {
-        (0..=display_row).into_iter().rev().flat_map(|row| {
+        (0..=display_row).rev().flat_map(|row| {
             self.block_snapshot
                 .chunks(row..row + 1, false, Highlights::default())
                 .map(|h| h.text)
@@ -1455,10 +1455,8 @@ pub mod tests {
             }"#
         .unindent();
 
-        let theme = SyntaxTheme::new_test(vec![
-            ("mod.body", Hsla::red().into()),
-            ("fn.name", Hsla::blue().into()),
-        ]);
+        let theme =
+            SyntaxTheme::new_test(vec![("mod.body", Hsla::red()), ("fn.name", Hsla::blue())]);
         let language = Arc::new(
             Language::new(
                 LanguageConfig {
@@ -1545,10 +1543,8 @@ pub mod tests {
             }"#
         .unindent();
 
-        let theme = SyntaxTheme::new_test(vec![
-            ("mod.body", Hsla::red().into()),
-            ("fn.name", Hsla::blue().into()),
-        ]);
+        let theme =
+            SyntaxTheme::new_test(vec![("mod.body", Hsla::red()), ("fn.name", Hsla::blue())]);
         let language = Arc::new(
             Language::new(
                 LanguageConfig {
@@ -1616,10 +1612,8 @@ pub mod tests {
     async fn test_chunks_with_text_highlights(cx: &mut gpui::TestAppContext) {
         cx.update(|cx| init_test(cx, |_| {}));
 
-        let theme = SyntaxTheme::new_test(vec![
-            ("operator", Hsla::red().into()),
-            ("string", Hsla::green().into()),
-        ]);
+        let theme =
+            SyntaxTheme::new_test(vec![("operator", Hsla::red()), ("string", Hsla::green())]);
         let language = Arc::new(
             Language::new(
                 LanguageConfig {

crates/editor/src/element.rs

@@ -2004,7 +2004,7 @@ impl EditorElement {
             let text_width = bounds.size.width - gutter_dimensions.width;
             let overscroll = size(em_width, px(0.));
             let _snapshot = {
-                editor.set_visible_line_count((bounds.size.height / line_height).into(), cx);
+                editor.set_visible_line_count(bounds.size.height / line_height, cx);
 
                 let editor_width = text_width - gutter_dimensions.margin - overscroll.width - em_width;
                 let wrap_width = match editor.soft_wrap_mode(cx) {
@@ -2037,7 +2037,7 @@ impl EditorElement {
             // The scroll position is a fractional point, the whole number of which represents
             // the top of the window in terms of display rows.
             let start_row = scroll_position.y as u32;
-            let height_in_lines = f32::from(bounds.size.height / line_height);
+            let height_in_lines = bounds.size.height / line_height;
             let max_row = snapshot.max_point().row();
 
             // Add 1 to ensure selections bleed off screen
@@ -2262,7 +2262,7 @@ impl EditorElement {
             });
 
             let scroll_max = point(
-                f32::from((scroll_width - text_size.width) / em_width).max(0.0),
+                ((scroll_width - text_size.width) / em_width).max(0.0),
                 max_row as f32,
             );
 
@@ -2722,11 +2722,8 @@ impl EditorElement {
                         };
 
                         let scroll_position = position_map.snapshot.scroll_position();
-                        let x = f32::from(
-                            (scroll_position.x * max_glyph_width - delta.x) / max_glyph_width,
-                        );
-                        let y =
-                            f32::from((scroll_position.y * line_height - delta.y) / line_height);
+                        let x = (scroll_position.x * max_glyph_width - delta.x) / max_glyph_width;
+                        let y = (scroll_position.y * line_height - delta.y) / line_height;
                         let scroll_position =
                             point(x, y).clamp(&point(0., 0.), &position_map.scroll_max);
                         editor.scroll(scroll_position, axis, cx);
@@ -3268,7 +3265,7 @@ impl PositionMap {
         let position = position - text_bounds.origin;
         let y = position.y.max(px(0.)).min(self.size.height);
         let x = position.x + (scroll_position.x * self.em_width);
-        let row = (f32::from(y / self.line_height) + scroll_position.y) as u32;
+        let row = ((y / self.line_height) + scroll_position.y) as u32;
 
         let (column, x_overshoot_after_line_end) = if let Some(line) = self
             .line_layouts

crates/editor/src/rust_analyzer_ext.rs

@@ -62,7 +62,6 @@ pub fn expand_macro_recursively(
             project
                 .read(cx)
                 .language_servers_for_buffer(buffer.read(cx), cx)
-                .into_iter()
                 .find_map(|(adapter, server)| {
                     if adapter.name.0.as_ref() == "rust-analyzer" {
                         Some((

crates/editor/src/scroll/autoscroll.rs

@@ -62,7 +62,7 @@ impl Editor {
         line_height: Pixels,
         cx: &mut ViewContext<Editor>,
     ) -> bool {
-        let visible_lines = f32::from(viewport_height / line_height);
+        let visible_lines = viewport_height / line_height;
         let display_map = self.display_map.update(cx, |map, cx| map.snapshot(cx));
         let mut scroll_position = self.scroll_manager.scroll_position(&display_map);
         let max_scroll_top = if matches!(self.mode, EditorMode::AutoHeight { .. }) {
@@ -241,11 +241,10 @@ impl Editor {
         let scroll_right = scroll_left + viewport_width;
 
         if target_left < scroll_left {
-            self.scroll_manager.anchor.offset.x = (target_left / max_glyph_width).into();
+            self.scroll_manager.anchor.offset.x = target_left / max_glyph_width;
             true
         } else if target_right > scroll_right {
-            self.scroll_manager.anchor.offset.x =
-                ((target_right - viewport_width) / max_glyph_width).into();
+            self.scroll_manager.anchor.offset.x = (target_right - viewport_width) / max_glyph_width;
             true
         } else {
             false