workspace: Fix dock/panel resizing (#50947)

Anthony Eid created 1 month ago

Before the panel resize wouldn't take into account the width of the
sidebar and the right dock could push the left dock on resize too.

Before you mark this PR as ready for review, make sure that you have:
- [ ] Added a solid test coverage and/or screenshots from doing manual
testing
- [x] Done a self-review taking into account security and performance
aspects
- [x] Aligned any UI changes with the [UI
checklist](https://github.com/zed-industries/zed/blob/main/CONTRIBUTING.md#uiux-checklist)


Co-authored-by: Cameron \<[e-mail]\>

Release Notes:

- N/A

Change summary

crates/workspace/src/workspace.rs | 20 ++++++++++++++++----
1 file changed, 16 insertions(+), 4 deletions(-)

Detailed changes

crates/workspace/src/workspace.rs

@@ -7085,7 +7085,17 @@ impl Workspace {
     }
 
     fn resize_left_dock(&mut self, new_size: Pixels, window: &mut Window, cx: &mut App) {
-        let size = new_size.min(self.bounds.right() - RESIZE_HANDLE_SIZE);
+        let workspace_width = self.bounds.size.width;
+        let mut size = new_size.min(workspace_width - RESIZE_HANDLE_SIZE);
+
+        self.right_dock.read_with(cx, |right_dock, cx| {
+            let right_dock_size = right_dock
+                .active_panel_size(window, cx)
+                .unwrap_or(Pixels::ZERO);
+            if right_dock_size + size > workspace_width {
+                size = workspace_width - right_dock_size
+            }
+        });
 
         self.left_dock.update(cx, |left_dock, cx| {
             if WorkspaceSettings::get_global(cx)
@@ -7100,13 +7110,14 @@ impl Workspace {
     }
 
     fn resize_right_dock(&mut self, new_size: Pixels, window: &mut Window, cx: &mut App) {
-        let mut size = new_size.max(self.bounds.left() - RESIZE_HANDLE_SIZE);
+        let workspace_width = self.bounds.size.width;
+        let mut size = new_size.min(workspace_width - RESIZE_HANDLE_SIZE);
         self.left_dock.read_with(cx, |left_dock, cx| {
             let left_dock_size = left_dock
                 .active_panel_size(window, cx)
                 .unwrap_or(Pixels::ZERO);
-            if left_dock_size + size > self.bounds.right() {
-                size = self.bounds.right() - left_dock_size
+            if left_dock_size + size > workspace_width {
+                size = workspace_width - left_dock_size
             }
         });
         self.right_dock.update(cx, |right_dock, cx| {
@@ -7667,6 +7678,7 @@ impl Render for Workspace {
                                             {
                                                 workspace.previous_dock_drag_coordinates =
                                                     Some(e.event.position);
+
                                                 match e.drag(cx).0 {
                                                     DockPosition::Left => {
                                                         workspace.resize_left_dock(