editor: Add indent guides. (#1426)

<img width="1070" height="1006" alt="image"
src="https://github.com/user-attachments/assets/a456b055-b45f-45ae-84b0-452a952cc19c"
/>

crates/story/examples/editor.rs

@@ -46,6 +46,7 @@ pub struct Example {
     language_state: Entity<DropdownState<Vec<SharedString>>>,
     language: Lang,
     line_number: bool,
+    indent_guides: bool,
     need_update: bool,
     soft_wrap: bool,
     lsp_store: ExampleLspStore,
@@ -671,6 +672,7 @@ impl Example {
             let mut editor = InputState::new(window, cx)
                 .code_editor(default_language.0.name().to_string())
                 .line_number(true)
+                .indent_guides(true)
                 .tab_size(TabSize {
                     tab_size: 4,
                     hard_tabs: false,
@@ -725,6 +727,7 @@ impl Example {
             language_state,
             language: default_language.0,
             line_number: true,
+            indent_guides: true,
             need_update: false,
             soft_wrap: false,
             lsp_store,
@@ -804,6 +807,19 @@ impl Example {
         cx.notify();
     }
 
+    fn toggle_indent_guides(
+        &mut self,
+        _: &ClickEvent,
+        window: &mut Window,
+        cx: &mut Context<Self>,
+    ) {
+        self.indent_guides = !self.indent_guides;
+        self.editor.update(cx, |state, cx| {
+            state.set_indent_guides(self.indent_guides, window, cx);
+        });
+        cx.notify();
+    }
+
     fn lint_document(&mut self, cx: &mut Context<Self>) {
         let language = self.language.name().to_string();
         let lsp_store = self.lsp_store.clone();
@@ -985,6 +1001,14 @@ impl Render for Example {
                                             .label("Soft Wrap")
                                             .selected(self.soft_wrap)
                                             .on_click(cx.listener(Self::toggle_soft_wrap))
+                                    })
+                                    .child({
+                                        Button::new("indent-guides")
+                                            .ghost()
+                                            .xsmall()
+                                            .label("Indent Guides")
+                                            .selected(self.indent_guides)
+                                            .on_click(cx.listener(Self::toggle_indent_guides))
                                     }),
                             )
                             .child({

crates/ui/src/input/element.rs

@@ -712,6 +712,7 @@ pub(super) struct PrepaintState {
     search_match_paths: Vec<(Path<Pixels>, bool)>,
     document_color_paths: Vec<(Path<Pixels>, Hsla)>,
     hover_definition_hitbox: Option<Hitbox>,
+    indent_guides_path: Option<Path<Pixels>>,
     bounds: Bounds<Pixels>,
 }
 
@@ -1083,6 +1084,7 @@ impl Element for TextElement {
         };
 
         let hover_definition_hitbox = self.layout_hover_definition_hitbox(state, window, cx);
+        let indent_guides_path = self.layout_indent_guides(state, &last_layout);
 
         PrepaintState {
             bounds,
@@ -1097,6 +1099,7 @@ impl Element for TextElement {
             hover_highlight_path,
             hover_definition_hitbox,
             document_color_paths,
+            indent_guides_path,
         }
     }
 
@@ -1189,6 +1192,11 @@ impl Element for TextElement {
             }
         }
 
+        // Paint indent guides
+        if let Some(path) = prepaint.indent_guides_path.take() {
+            window.paint_path(path, cx.theme().secondary);
+        }
+
         // Paint selections
         if window.is_window_active() {
             let secondary_selection = cx.theme().selection.saturation(0.1);

crates/ui/src/input/indent.rs

@@ -0,0 +1,391 @@
+use gpui::{
+    point, px, Context, EntityInputHandler as _, Path, PathBuilder, Pixels, SharedString, Window,
+};
+use ropey::RopeSlice;
+
+use crate::{
+    input::{
+        element::TextElement, mode::InputMode, Indent, IndentInline, InputState, LastLayout,
+        Outdent, OutdentInline,
+    },
+    RopeExt,
+};
+
+#[derive(Debug, Copy, Clone)]
+pub struct TabSize {
+    /// Default is 2
+    pub tab_size: usize,
+    /// Set true to use `\t` as tab indent, default is false
+    pub hard_tabs: bool,
+}
+
+impl Default for TabSize {
+    fn default() -> Self {
+        Self {
+            tab_size: 2,
+            hard_tabs: false,
+        }
+    }
+}
+
+impl TabSize {
+    pub(super) fn to_string(&self) -> SharedString {
+        if self.hard_tabs {
+            "\t".into()
+        } else {
+            " ".repeat(self.tab_size).into()
+        }
+    }
+
+    /// Count the indent size of the line in spaces.
+    pub fn indent_count(&self, line: &RopeSlice) -> usize {
+        let mut count = 0;
+        for ch in line.chars() {
+            match ch {
+                '\t' => count += self.tab_size,
+                ' ' => count += 1,
+                _ => break,
+            }
+        }
+
+        count
+    }
+}
+
+impl InputMode {
+    #[inline]
+    pub(super) fn is_indentable(&self) -> bool {
+        matches!(
+            self,
+            InputMode::MultiLine { .. } | InputMode::CodeEditor { .. }
+        )
+    }
+
+    #[inline]
+    pub(super) fn has_indent_guides(&self) -> bool {
+        match self {
+            InputMode::CodeEditor { indent_guides, .. } => *indent_guides,
+            _ => false,
+        }
+    }
+
+    #[inline]
+    pub(super) fn tab_size(&self) -> TabSize {
+        match self {
+            InputMode::MultiLine { tab, .. } => *tab,
+            InputMode::CodeEditor { tab, .. } => *tab,
+            _ => TabSize::default(),
+        }
+    }
+}
+
+impl TextElement {
+    pub(super) fn layout_indent_guides(
+        &self,
+        state: &InputState,
+        last_layout: &LastLayout,
+    ) -> Option<Path<Pixels>> {
+        if !state.mode.has_indent_guides() {
+            return None;
+        }
+
+        let tab_size = state.mode.tab_size();
+        let line_height = last_layout.line_height;
+        let visible_range = last_layout.visible_range.clone();
+        let mut builder = PathBuilder::stroke(px(1.));
+        let mut offset_y =
+            last_layout.visible_top + state.scroll_handle.offset().y + (line_height * 2 - px(3.));
+        let mut last_indents = vec![];
+        for ix in visible_range {
+            let line = state.text.slice_line(ix);
+            let line_layout = last_layout.line(ix).expect("line layout should exist");
+            let mut current_indents = vec![];
+            if line.len() > 0 {
+                let indent_count = tab_size.indent_count(&line);
+                for offset in (0..indent_count).step_by(tab_size.tab_size) {
+                    let mut pos = line_layout
+                        .position_for_index(offset, line_height)
+                        .unwrap_or(point(px(0.), px(0.)));
+
+                    pos.x += last_layout.line_number_width;
+                    pos.y += offset_y;
+
+                    builder.move_to(pos);
+                    builder.line_to(point(pos.x, pos.y + line_height));
+                    current_indents.push(pos.x);
+                }
+            } else if last_indents.len() > 0 {
+                for x in &last_indents {
+                    let pos = point(*x, offset_y);
+                    builder.move_to(pos);
+                    builder.line_to(point(pos.x, pos.y + line_height));
+                }
+                current_indents = last_indents.clone();
+            }
+
+            offset_y += line_layout.wrapped_lines.len() * line_height;
+            last_indents = current_indents;
+        }
+
+        let path = builder.build().unwrap();
+        Some(path)
+    }
+}
+
+impl InputState {
+    /// Set whether to show indent guides in code editor mode, default is true.
+    ///
+    /// Only for [`InputMode::CodeEditor`] mode.
+    pub fn indent_guides(mut self, indent_guides: bool) -> Self {
+        debug_assert!(self.mode.is_code_editor());
+        if let InputMode::CodeEditor {
+            indent_guides: l, ..
+        } = &mut self.mode
+        {
+            *l = indent_guides;
+        }
+        self
+    }
+
+    /// Set indent guides in code editor mode.
+    ///
+    /// Only for [`InputMode::CodeEditor`] mode.
+    pub fn set_indent_guides(
+        &mut self,
+        indent_guides: bool,
+        _: &mut Window,
+        cx: &mut Context<Self>,
+    ) {
+        debug_assert!(self.mode.is_code_editor());
+        if let InputMode::CodeEditor {
+            indent_guides: l, ..
+        } = &mut self.mode
+        {
+            *l = indent_guides;
+        }
+        cx.notify();
+    }
+
+    /// Set the tab size for the input.
+    ///
+    /// Only for [`InputMode::MultiLine`] and [`InputMode::CodeEditor`] mode.
+    pub fn tab_size(mut self, tab: TabSize) -> Self {
+        debug_assert!(self.mode.is_multi_line() || self.mode.is_code_editor());
+        match &mut self.mode {
+            InputMode::MultiLine { tab: t, .. } => *t = tab,
+            InputMode::CodeEditor { tab: t, .. } => *t = tab,
+            _ => {}
+        }
+        self
+    }
+
+    pub(super) fn indent_inline(
+        &mut self,
+        _: &IndentInline,
+        window: &mut Window,
+        cx: &mut Context<Self>,
+    ) {
+        self.indent(false, window, cx);
+    }
+
+    pub(super) fn indent_block(&mut self, _: &Indent, window: &mut Window, cx: &mut Context<Self>) {
+        self.indent(true, window, cx);
+    }
+
+    pub(super) fn outdent_inline(
+        &mut self,
+        _: &OutdentInline,
+        window: &mut Window,
+        cx: &mut Context<Self>,
+    ) {
+        self.outdent(false, window, cx);
+    }
+
+    pub(super) fn outdent_block(
+        &mut self,
+        _: &Outdent,
+        window: &mut Window,
+        cx: &mut Context<Self>,
+    ) {
+        self.outdent(true, window, cx);
+    }
+
+    pub(super) fn indent(&mut self, block: bool, window: &mut Window, cx: &mut Context<Self>) {
+        if !self.mode.is_indentable() {
+            cx.propagate();
+            return;
+        };
+
+        let tab_indent = self.mode.tab_size().to_string();
+        let selected_range = self.selected_range;
+        let mut added_len = 0;
+        let is_selected = !self.selected_range.is_empty();
+
+        if is_selected || block {
+            let start_offset = self.start_of_line_of_selection(window, cx);
+            let mut offset = start_offset;
+
+            let selected_text = self
+                .text_for_range(
+                    self.range_to_utf16(&(offset..selected_range.end)),
+                    &mut None,
+                    window,
+                    cx,
+                )
+                .unwrap_or("".into());
+
+            for line in selected_text.split('\n') {
+                self.replace_text_in_range_silent(
+                    Some(self.range_to_utf16(&(offset..offset))),
+                    &tab_indent,
+                    window,
+                    cx,
+                );
+                added_len += tab_indent.len();
+                // +1 for "\n", the `\r` is included in the `line`.
+                offset += line.len() + tab_indent.len() + 1;
+            }
+
+            if is_selected {
+                self.selected_range = (start_offset..selected_range.end + added_len).into();
+            } else {
+                self.selected_range =
+                    (selected_range.start + added_len..selected_range.end + added_len).into();
+            }
+        } else {
+            // Selected none
+            let offset = self.selected_range.start;
+            self.replace_text_in_range_silent(
+                Some(self.range_to_utf16(&(offset..offset))),
+                &tab_indent,
+                window,
+                cx,
+            );
+            added_len = tab_indent.len();
+
+            self.selected_range =
+                (selected_range.start + added_len..selected_range.end + added_len).into();
+        }
+    }
+
+    pub(super) fn outdent(&mut self, block: bool, window: &mut Window, cx: &mut Context<Self>) {
+        if !self.mode.is_indentable() {
+            cx.propagate();
+            return;
+        };
+
+        let tab_indent = self.mode.tab_size().to_string();
+        let selected_range = self.selected_range;
+        let mut removed_len = 0;
+        let is_selected = !self.selected_range.is_empty();
+
+        if is_selected || block {
+            let start_offset = self.start_of_line_of_selection(window, cx);
+            let mut offset = start_offset;
+
+            let selected_text = self
+                .text_for_range(
+                    self.range_to_utf16(&(offset..selected_range.end)),
+                    &mut None,
+                    window,
+                    cx,
+                )
+                .unwrap_or("".into());
+
+            for line in selected_text.split('\n') {
+                if line.starts_with(tab_indent.as_ref()) {
+                    self.replace_text_in_range_silent(
+                        Some(self.range_to_utf16(&(offset..offset + tab_indent.len()))),
+                        "",
+                        window,
+                        cx,
+                    );
+                    removed_len += tab_indent.len();
+
+                    // +1 for "\n"
+                    offset += line.len().saturating_sub(tab_indent.len()) + 1;
+                } else {
+                    offset += line.len() + 1;
+                }
+            }
+
+            if is_selected {
+                self.selected_range =
+                    (start_offset..selected_range.end.saturating_sub(removed_len)).into();
+            } else {
+                self.selected_range = (selected_range.start.saturating_sub(removed_len)
+                    ..selected_range.end.saturating_sub(removed_len))
+                    .into();
+            }
+        } else {
+            // Selected none
+            let start_offset = self.selected_range.start;
+            let offset = self.start_of_line_of_selection(window, cx);
+            let offset = self.offset_from_utf16(self.offset_to_utf16(offset));
+            // FIXME: To improve performance
+            if self
+                .text
+                .slice(offset..self.text.len())
+                .to_string()
+                .starts_with(tab_indent.as_ref())
+            {
+                self.replace_text_in_range_silent(
+                    Some(self.range_to_utf16(&(offset..offset + tab_indent.len()))),
+                    "",
+                    window,
+                    cx,
+                );
+                removed_len = tab_indent.len();
+                let new_offset = start_offset.saturating_sub(removed_len);
+                self.selected_range = (new_offset..new_offset).into();
+            }
+        }
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use ropey::RopeSlice;
+
+    use super::TabSize;
+
+    #[test]
+    fn test_tab_size() {
+        let tab = TabSize {
+            tab_size: 2,
+            hard_tabs: false,
+        };
+        assert_eq!(tab.to_string(), "  ");
+        let tab = TabSize {
+            tab_size: 4,
+            hard_tabs: false,
+        };
+        assert_eq!(tab.to_string(), "    ");
+
+        let tab = TabSize {
+            tab_size: 2,
+            hard_tabs: true,
+        };
+        assert_eq!(tab.to_string(), "\t");
+        let tab = TabSize {
+            tab_size: 4,
+            hard_tabs: true,
+        };
+        assert_eq!(tab.to_string(), "\t");
+    }
+
+    #[test]
+    fn test_tab_size_indent_count() {
+        let tab = TabSize {
+            tab_size: 4,
+            hard_tabs: false,
+        };
+        assert_eq!(tab.indent_count(&RopeSlice::from("abc")), 0);
+        assert_eq!(tab.indent_count(&RopeSlice::from("  abc")), 2);
+        assert_eq!(tab.indent_count(&RopeSlice::from("    abc")), 4);
+        assert_eq!(tab.indent_count(&RopeSlice::from("\tabc")), 4);
+        assert_eq!(tab.indent_count(&RopeSlice::from("  \tabc")), 6);
+        assert_eq!(tab.indent_count(&RopeSlice::from(" \t abc  ")), 6);
+        assert_eq!(tab.indent_count(&RopeSlice::from("abc")), 0);
+    }
+}

crates/ui/src/input/mod.rs

@@ -3,6 +3,7 @@ mod change;
 mod clear_button;
 mod cursor;
 mod element;
+mod indent;
 mod lsp;
 mod mask_pattern;
 mod mode;
@@ -18,9 +19,9 @@ mod text_wrapper;
 
 pub(crate) use clear_button::*;
 pub use cursor::*;
+pub use indent::TabSize;
 pub use lsp::*;
 pub use mask_pattern::MaskPattern;
-pub use mode::TabSize;
 pub use number_input::{NumberInput, NumberInputEvent, StepAction};
 pub use otp_input::*;
 pub use state::*;

crates/ui/src/input/mode.rs

@@ -8,34 +8,7 @@ use tree_sitter::InputEdit;
 use super::text_wrapper::TextWrapper;
 use crate::highlighter::DiagnosticSet;
 use crate::highlighter::SyntaxHighlighter;
-use crate::input::RopeExt as _;
-
-#[derive(Debug, Copy, Clone)]
-pub struct TabSize {
-    /// Default is 2
-    pub tab_size: usize,
-    /// Set true to use `\t` as tab indent, default is false
-    pub hard_tabs: bool,
-}
-
-impl Default for TabSize {
-    fn default() -> Self {
-        Self {
-            tab_size: 2,
-            hard_tabs: false,
-        }
-    }
-}
-
-impl TabSize {
-    pub(super) fn to_string(&self) -> SharedString {
-        if self.hard_tabs {
-            "\t".into()
-        } else {
-            " ".repeat(self.tab_size).into()
-        }
-    }
-}
+use crate::input::{RopeExt as _, TabSize};
 
 #[derive(Default, Clone)]
 pub enum InputMode {
@@ -56,6 +29,7 @@ pub enum InputMode {
         /// Show line number
         line_number: bool,
         language: SharedString,
+        indent_guides: bool,
         highlighter: Rc<RefCell<Option<SyntaxHighlighter>>>,
         diagnostics: DiagnosticSet,
     },
@@ -155,15 +129,6 @@ impl InputMode {
         }
     }
 
-    #[inline]
-    pub(super) fn tab_size(&self) -> Option<&TabSize> {
-        match self {
-            InputMode::MultiLine { tab, .. } => Some(tab),
-            InputMode::CodeEditor { tab, .. } => Some(tab),
-            _ => None,
-        }
-    }
-
     pub(super) fn update_highlighter(
         &mut self,
         selected_range: &Range<usize>,
@@ -237,33 +202,3 @@ impl InputMode {
         }
     }
 }
-
-#[cfg(test)]
-mod tests {
-    use super::TabSize;
-
-    #[test]
-    fn test_tab_size() {
-        let tab = TabSize {
-            tab_size: 2,
-            hard_tabs: false,
-        };
-        assert_eq!(tab.to_string(), "  ");
-        let tab = TabSize {
-            tab_size: 4,
-            hard_tabs: false,
-        };
-        assert_eq!(tab.to_string(), "    ");
-
-        let tab = TabSize {
-            tab_size: 2,
-            hard_tabs: true,
-        };
-        assert_eq!(tab.to_string(), "\t");
-        let tab = TabSize {
-            tab_size: 4,
-            hard_tabs: true,
-        };
-        assert_eq!(tab.to_string(), "\t");
-    }
-}

crates/ui/src/input/state.rs

@@ -19,13 +19,8 @@ use sum_tree::Bias;
 use unicode_segmentation::*;
 
 use super::{
-    blink_cursor::BlinkCursor,
-    change::Change,
-    element::TextElement,
-    mask_pattern::MaskPattern,
-    mode::{InputMode, TabSize},
-    number_input,
-    text_wrapper::TextWrapper,
+    blink_cursor::BlinkCursor, change::Change, element::TextElement, mask_pattern::MaskPattern,
+    mode::InputMode, number_input, text_wrapper::TextWrapper, TabSize,
 };
 use crate::actions::{SelectDown, SelectLeft, SelectRight, SelectUp};
 use crate::input::{
@@ -468,6 +463,7 @@ impl InputState {
             language,
             highlighter: Rc::new(RefCell::new(None)),
             line_number: true,
+            indent_guides: true,
             diagnostics: DiagnosticSet::new(&Rope::new()),
         };
         self.searchable = true;
@@ -505,19 +501,6 @@ impl InputState {
         cx.notify();
     }
 
-    /// Set the tab size for the input.
-    ///
-    /// Only for [`InputMode::MultiLine`] and [`InputMode::CodeEditor`] mode.
-    pub fn tab_size(mut self, tab: TabSize) -> Self {
-        debug_assert!(self.mode.is_multi_line() || self.mode.is_code_editor());
-        match &mut self.mode {
-            InputMode::MultiLine { tab: t, .. } => *t = tab,
-            InputMode::CodeEditor { tab: t, .. } => *t = tab,
-            _ => {}
-        }
-        self
-    }
-
     /// Set the number of rows for the multi-line Textarea.
     ///
     /// This is only used when `multi_line` is set to true.
@@ -992,7 +975,11 @@ impl InputState {
     /// Get start line of selection start or end (The min value).
     ///
     /// This is means is always get the first line of selection.
-    fn start_of_line_of_selection(&mut self, window: &mut Window, cx: &mut Context<Self>) -> usize {
+    pub(super) fn start_of_line_of_selection(
+        &mut self,
+        window: &mut Window,
+        cx: &mut Context<Self>,
+    ) -> usize {
         if self.mode.is_single_line() {
             return 0;
         }
@@ -1165,169 +1152,6 @@ impl InputState {
         });
     }
 
-    pub(super) fn indent_inline(
-        &mut self,
-        _: &IndentInline,
-        window: &mut Window,
-        cx: &mut Context<Self>,
-    ) {
-        self.indent(false, window, cx);
-    }
-
-    pub(super) fn indent_block(&mut self, _: &Indent, window: &mut Window, cx: &mut Context<Self>) {
-        self.indent(true, window, cx);
-    }
-
-    pub(super) fn outdent_inline(
-        &mut self,
-        _: &OutdentInline,
-        window: &mut Window,
-        cx: &mut Context<Self>,
-    ) {
-        self.outdent(false, window, cx);
-    }
-
-    pub(super) fn outdent_block(
-        &mut self,
-        _: &Outdent,
-        window: &mut Window,
-        cx: &mut Context<Self>,
-    ) {
-        self.outdent(true, window, cx);
-    }
-
-    pub(super) fn indent(&mut self, block: bool, window: &mut Window, cx: &mut Context<Self>) {
-        let Some(tab_size) = self.mode.tab_size() else {
-            cx.propagate();
-            return;
-        };
-
-        let tab_indent = tab_size.to_string();
-        let selected_range = self.selected_range;
-        let mut added_len = 0;
-        let is_selected = !self.selected_range.is_empty();
-
-        if is_selected || block {
-            let start_offset = self.start_of_line_of_selection(window, cx);
-            let mut offset = start_offset;
-
-            let selected_text = self
-                .text_for_range(
-                    self.range_to_utf16(&(offset..selected_range.end)),
-                    &mut None,
-                    window,
-                    cx,
-                )
-                .unwrap_or("".into());
-
-            for line in selected_text.split('\n') {
-                self.replace_text_in_range_silent(
-                    Some(self.range_to_utf16(&(offset..offset))),
-                    &tab_indent,
-                    window,
-                    cx,
-                );
-                added_len += tab_indent.len();
-                // +1 for "\n", the `\r` is included in the `line`.
-                offset += line.len() + tab_indent.len() + 1;
-            }
-
-            if is_selected {
-                self.selected_range = (start_offset..selected_range.end + added_len).into();
-            } else {
-                self.selected_range =
-                    (selected_range.start + added_len..selected_range.end + added_len).into();
-            }
-        } else {
-            // Selected none
-            let offset = self.selected_range.start;
-            self.replace_text_in_range_silent(
-                Some(self.range_to_utf16(&(offset..offset))),
-                &tab_indent,
-                window,
-                cx,
-            );
-            added_len = tab_indent.len();
-
-            self.selected_range =
-                (selected_range.start + added_len..selected_range.end + added_len).into();
-        }
-    }
-
-    pub(super) fn outdent(&mut self, block: bool, window: &mut Window, cx: &mut Context<Self>) {
-        let Some(tab_size) = self.mode.tab_size() else {
-            cx.propagate();
-            return;
-        };
-
-        let tab_indent = tab_size.to_string();
-        let selected_range = self.selected_range;
-        let mut removed_len = 0;
-        let is_selected = !self.selected_range.is_empty();
-
-        if is_selected || block {
-            let start_offset = self.start_of_line_of_selection(window, cx);
-            let mut offset = start_offset;
-
-            let selected_text = self
-                .text_for_range(
-                    self.range_to_utf16(&(offset..selected_range.end)),
-                    &mut None,
-                    window,
-                    cx,
-                )
-                .unwrap_or("".into());
-
-            for line in selected_text.split('\n') {
-                if line.starts_with(tab_indent.as_ref()) {
-                    self.replace_text_in_range_silent(
-                        Some(self.range_to_utf16(&(offset..offset + tab_indent.len()))),
-                        "",
-                        window,
-                        cx,
-                    );
-                    removed_len += tab_indent.len();
-
-                    // +1 for "\n"
-                    offset += line.len().saturating_sub(tab_indent.len()) + 1;
-                } else {
-                    offset += line.len() + 1;
-                }
-            }
-
-            if is_selected {
-                self.selected_range =
-                    (start_offset..selected_range.end.saturating_sub(removed_len)).into();
-            } else {
-                self.selected_range = (selected_range.start.saturating_sub(removed_len)
-                    ..selected_range.end.saturating_sub(removed_len))
-                    .into();
-            }
-        } else {
-            // Selected none
-            let start_offset = self.selected_range.start;
-            let offset = self.start_of_line_of_selection(window, cx);
-            let offset = self.offset_from_utf16(self.offset_to_utf16(offset));
-            // FIXME: To improve performance
-            if self
-                .text
-                .slice(offset..self.text.len())
-                .to_string()
-                .starts_with(tab_indent.as_ref())
-            {
-                self.replace_text_in_range_silent(
-                    Some(self.range_to_utf16(&(offset..offset + tab_indent.len()))),
-                    "",
-                    window,
-                    cx,
-                );
-                removed_len = tab_indent.len();
-                let new_offset = start_offset.saturating_sub(removed_len);
-                self.selected_range = (new_offset..new_offset).into();
-            }
-        }
-    }
-
     pub(super) fn clean(&mut self, window: &mut Window, cx: &mut Context<Self>) {
         self.replace_text("", window, cx);
         self.selected_range = (0..0).into();