vim: Add Smart Relative Line Number (#16567)

Closes #16514

Release Notes:

- Added Vim: absolute numbering in any mode except `insert` mode

---------

Co-authored-by: Conrad Irwin <conrad.irwin@gmail.com>

crates/vim/src/vim.rs

@@ -23,8 +23,8 @@ use editor::{
     Anchor, Bias, Editor, EditorEvent, EditorMode, ToPoint,
 };
 use gpui::{
-    actions, impl_actions, Action, AppContext, EventEmitter, KeyContext, KeystrokeEvent, Render,
-    View, ViewContext, WeakView,
+    actions, impl_actions, Action, AppContext, Entity, EventEmitter, KeyContext, KeystrokeEvent,
+    Render, View, ViewContext, WeakView,
 };
 use insert::NormalBefore;
 use language::{CursorShape, Point, Selection, SelectionGoal, TransactionId};
@@ -228,8 +228,21 @@ impl Vim {
         }
 
         let mut was_enabled = Vim::enabled(cx);
+        let mut was_toggle = VimSettings::get_global(cx).toggle_relative_line_numbers;
         cx.observe_global::<SettingsStore>(move |editor, cx| {
             let enabled = Vim::enabled(cx);
+            let toggle = VimSettings::get_global(cx).toggle_relative_line_numbers;
+            if enabled && was_enabled && (toggle != was_toggle) {
+                if toggle {
+                    let is_relative = editor
+                        .addon::<VimAddon>()
+                        .map(|vim| vim.view.read(cx).mode != Mode::Insert);
+                    editor.set_relative_line_number(is_relative, cx)
+                } else {
+                    editor.set_relative_line_number(None, cx)
+                }
+            }
+            was_toggle = VimSettings::get_global(cx).toggle_relative_line_numbers;
             if was_enabled == enabled {
                 return;
             }
@@ -296,6 +309,7 @@ impl Vim {
         editor.set_autoindent(true);
         editor.selections.line_mode = false;
         editor.unregister_addon::<VimAddon>();
+        editor.set_relative_line_number(None, cx)
     }
 
     /// Register an action on the editor.
@@ -424,6 +438,17 @@ impl Vim {
         // Sync editor settings like clip mode
         self.sync_vim_settings(cx);
 
+        if VimSettings::get_global(cx).toggle_relative_line_numbers {
+            if self.mode != self.last_mode {
+                if self.mode == Mode::Insert || self.last_mode == Mode::Insert {
+                    self.update_editor(cx, |vim, editor, cx| {
+                        let is_relative = vim.mode != Mode::Insert;
+                        editor.set_relative_line_number(Some(is_relative), cx)
+                    });
+                }
+            }
+        }
+
         if leave_selections {
             return;
         }
@@ -616,6 +641,24 @@ impl Vim {
 
         cx.emit(VimEvent::Focused);
         self.sync_vim_settings(cx);
+
+        if VimSettings::get_global(cx).toggle_relative_line_numbers {
+            if let Some(old_vim) = Vim::globals(cx).focused_vim() {
+                if old_vim.entity_id() != cx.view().entity_id() {
+                    old_vim.update(cx, |vim, cx| {
+                        vim.update_editor(cx, |_, editor, cx| {
+                            editor.set_relative_line_number(None, cx)
+                        });
+                    });
+
+                    self.update_editor(cx, |vim, editor, cx| {
+                        let is_relative = vim.mode != Mode::Insert;
+                        editor.set_relative_line_number(Some(is_relative), cx)
+                    });
+                }
+            }
+        }
+        Vim::globals(cx).focused_vim = Some(cx.view().downgrade());
     }
 
     fn blurred(&mut self, cx: &mut ViewContext<Self>) {
@@ -1039,6 +1082,7 @@ pub enum UseSystemClipboard {
 
 #[derive(Deserialize)]
 struct VimSettings {
+    pub toggle_relative_line_numbers: bool,
     pub use_system_clipboard: UseSystemClipboard,
     pub use_multiline_find: bool,
     pub use_smartcase_find: bool,
@@ -1047,6 +1091,7 @@ struct VimSettings {
 
 #[derive(Clone, Default, Serialize, Deserialize, JsonSchema)]
 struct VimSettingsContent {
+    pub toggle_relative_line_numbers: Option<bool>,
     pub use_system_clipboard: Option<UseSystemClipboard>,
     pub use_multiline_find: Option<bool>,
     pub use_smartcase_find: Option<bool>,