agent: Improve edit file tool card (#29448)

⚠️ Work in progress until all of the to-dos are knocked out:

- [x] Disable soft-wrapping
- [x] Make it foldable only after a certain number of lines
- [x] Display tool status errors
- [x] Fix horizontal scroll now that we've disabled soft-wrap
- [ ] Don't render unnecessary extra lines (will be added later, on a
follow-up PR)

Release Notes:

- N/A

---------

Co-authored-by: Agus Zubiaga <hi@aguz.me>
Co-authored-by: Michael Sloan <mgsloan@gmail.com>

crates/editor/src/editor.rs

@@ -871,7 +871,6 @@ pub struct Editor {
     show_breadcrumbs: bool,
     show_gutter: bool,
     show_scrollbars: bool,
-    disable_scrolling: bool,
     disable_expand_excerpt_buttons: bool,
     show_line_numbers: Option<bool>,
     use_relative_line_numbers: Option<bool>,
@@ -1668,7 +1667,6 @@ impl Editor {
             blink_manager: blink_manager.clone(),
             show_local_selections: true,
             show_scrollbars: true,
-            disable_scrolling: false,
             mode,
             show_breadcrumbs: EditorSettings::get_global(cx).toolbar.breadcrumbs,
             show_gutter: mode.is_full(),
@@ -16487,11 +16485,6 @@ impl Editor {
         cx.notify();
     }
 
-    pub fn disable_scrolling(&mut self, cx: &mut Context<Self>) {
-        self.disable_scrolling = true;
-        cx.notify();
-    }
-
     pub fn set_show_line_numbers(&mut self, show_line_numbers: bool, cx: &mut Context<Self>) {
         self.show_line_numbers = Some(show_line_numbers);
         cx.notify();

crates/editor/src/element.rs

@@ -5678,9 +5678,7 @@ impl EditorElement {
     }
 
     fn paint_mouse_listeners(&mut self, layout: &EditorLayout, window: &mut Window, cx: &mut App) {
-        if !self.editor.read(cx).disable_scrolling {
-            self.paint_scroll_wheel_listener(layout, window, cx);
-        }
+        self.paint_scroll_wheel_listener(layout, window, cx);
 
         window.on_mouse_event({
             let position_map = layout.position_map.clone();

crates/editor/src/scroll.rs

@@ -184,9 +184,6 @@ impl ScrollManager {
         window: &mut Window,
         cx: &mut Context<Editor>,
     ) {
-        if self.forbid_vertical_scroll {
-            return;
-        }
         let (new_anchor, top_row) = if scroll_position.y <= 0. {
             (
                 ScrollAnchor {
@@ -258,10 +255,16 @@ impl ScrollManager {
         window: &mut Window,
         cx: &mut Context<Editor>,
     ) {
-        if self.forbid_vertical_scroll {
-            return;
-        }
-        self.anchor = anchor;
+        let adjusted_anchor = if self.forbid_vertical_scroll {
+            ScrollAnchor {
+                offset: gpui::Point::new(anchor.offset.x, self.anchor.offset.y),
+                anchor: self.anchor.anchor,
+            }
+        } else {
+            anchor
+        };
+
+        self.anchor = adjusted_anchor;
         cx.emit(EditorEvent::ScrollPositionChanged { local, autoscroll });
         self.show_scrollbars(window, cx);
         self.autoscroll_request.take();
@@ -404,11 +407,12 @@ impl Editor {
         window: &mut Window,
         cx: &mut Context<Self>,
     ) {
+        let mut delta = scroll_delta;
         if self.scroll_manager.forbid_vertical_scroll {
-            return;
+            delta.y = 0.0;
         }
         let display_map = self.display_map.update(cx, |map, cx| map.snapshot(cx));
-        let position = self.scroll_manager.anchor.scroll_position(&display_map) + scroll_delta;
+        let position = self.scroll_manager.anchor.scroll_position(&display_map) + delta;
         self.set_scroll_position_taking_display_map(position, true, false, display_map, window, cx);
     }
 
@@ -418,10 +422,12 @@ impl Editor {
         window: &mut Window,
         cx: &mut Context<Self>,
     ) {
+        let mut position = scroll_position;
         if self.scroll_manager.forbid_vertical_scroll {
-            return;
+            let current_position = self.scroll_position(cx);
+            position.y = current_position.y;
         }
-        self.set_scroll_position_internal(scroll_position, true, false, window, cx);
+        self.set_scroll_position_internal(position, true, false, window, cx);
     }
 
     /// Scrolls so that `row` is at the top of the editor view.
@@ -480,8 +486,15 @@ impl Editor {
         self.edit_prediction_preview
             .set_previous_scroll_position(None);
 
+        let adjusted_position = if self.scroll_manager.forbid_vertical_scroll {
+            let current_position = self.scroll_manager.anchor.scroll_position(&display_map);
+            gpui::Point::new(scroll_position.x, current_position.y)
+        } else {
+            scroll_position
+        };
+
         self.scroll_manager.set_scroll_position(
-            scroll_position,
+            adjusted_position,
             &display_map,
             local,
             autoscroll,