From 4cbd8fbde30937df7cebd6037d5b76016cd56e04 Mon Sep 17 00:00:00 2001
From: CJ van den Berg <cj@vdbonline.com>
Date: Mon, 23 Feb 2026 21:48:41 +0100
Subject: [PATCH] fix: prevent endless looping on tab bar widget updates

Now that Widget addresses do not have to be stable we can greatly simplfy
and in the process eliminate the potential for update looping.

The closes #520
---
 src/tui/status/tabs.zig | 38 +++++++++++++-------------------------
 1 file changed, 13 insertions(+), 25 deletions(-)

diff --git a/src/tui/status/tabs.zig b/src/tui/status/tabs.zig
index 2d76eaf..2807ec2 100644
--- a/src/tui/status/tabs.zig
+++ b/src/tui/status/tabs.zig
@@ -159,12 +159,13 @@ pub const TabBar = struct {
 
     pub fn update(self: *Self) void {
         const drag_source, const drag_btn = tui.get_drag_source();
-        self.update_tabs(drag_source) catch {};
+        const tab_update = self.update_tabs(drag_source) catch true;
         self.splits_list_widget.resize(Widget.Box.from(self.plane));
         self.splits_list_widget.update();
+        if (!tab_update) return;
         for (self.splits_list.widgets.items) |*split_widgetstate| if (split_widgetstate.widget.dynamic_cast(WidgetList)) |split|
             for (split.widgets.items) |*widgetstate| if (widgetstate.widget.dynamic_cast(Tab.ButtonType)) |btn| if (btn.drag_pos) |_|
-                tui.update_drag_source(&widgetstate.widget, drag_btn);
+                tui.update_drag_source(widgetstate.widget, drag_btn);
         tui.refresh_hover(@src());
     }
 
@@ -313,53 +314,42 @@ pub const TabBar = struct {
             if (tab.widget.dynamic_cast(Tab.ButtonType)) |btn|
                 if (btn.drag_pos) |_| break true;
         } else false;
-        if (!dragging and !buffers_changed and self.splits_list.widgets.items.len > 0) return;
+        if (!dragging and !buffers_changed and self.splits_list.widgets.items.len > 0) return false;
         try self.update_tab_widgets(drag_source);
+        return true;
     }
 
-    fn update_tab_widgets(self: *Self, drag_source: ?*Widget) !void {
+    fn update_tab_widgets(self: *Self, drag_source_: ?Widget) !void {
+        tp.trace(tp.channel.debug, .{"update_tab_widgets"});
         const mv = tui.mainview() orelse @panic("tabs no main view");
         const buffer_manager = tui.get_buffer_manager() orelse @panic("tabs no buffer manager");
-        var prev_widget_count: usize = 0;
 
-        for (self.splits_list.widgets.items) |*split_widgetstate| if (split_widgetstate.widget.dynamic_cast(WidgetList)) |split| {
-            prev_widget_count += 1;
-            for (split.widgets.items) |_| prev_widget_count += 1;
-        };
-
-        for (self.splits_list.widgets.items) |*split_widget| if (split_widget.widget.dynamic_cast(WidgetList)) |split| {
-            for (split.widgets.items) |*widget|
-                if (&widget.widget == drag_source) tui.reset_drag_context();
-        };
+        if (drag_source_) |drag_source|
+            for (self.splits_list.widgets.items) |*split_widget| if (split_widget.widget.dynamic_cast(WidgetList)) |split| {
+                for (split.widgets.items) |widget|
+                    if (widget.widget.ptr == drag_source.ptr) tui.reset_drag_context();
+            };
         while (self.splits_list.pop()) |split_widget| if (split_widget.dynamic_cast(WidgetList)) |split| {
             while (split.pop()) |widget| if (widget.dynamic_cast(Tab.ButtonType) == null)
                 widget.deinit(self.splits_list.allocator);
             split.deinit(self.splits_list.allocator);
         };
 
-        for (self.tabs) |*tab| if (buffer_manager.buffer_from_ref(tab.buffer_ref)) |buffer| {
-            tab.view = buffer.get_last_view() orelse 0;
-        };
-
         const views = mv.get_view_count();
 
-        var widget_count: usize = 0;
         for (0..views) |view| {
             var first = true;
             var view_widget_list = try WidgetList.createH(self.allocator, self.splits_list.plane, "split", .dynamic);
             try self.splits_list.add(view_widget_list.widget());
-            widget_count += 1;
-            for (self.tabs) |tab| {
+            for (self.tabs) |*tab| {
                 const tab_view = tab.view orelse 0;
                 if (tab_view != view) continue;
                 if (first) {
                     first = false;
                 } else {
                     try view_widget_list.add(try self.make_spacer(view_widget_list.plane));
-                    widget_count += 1;
                 }
                 try view_widget_list.add(tab.widget);
-                widget_count += 1;
                 if (tab.widget.dynamic_cast(Tab.ButtonType)) |btn| {
                     if (buffer_manager.buffer_from_ref(tab.buffer_ref)) |buffer| {
                         try btn.update_label(Tab.name_from_buffer(buffer));
@@ -369,8 +359,6 @@ pub const TabBar = struct {
             }
             try view_widget_list.add(try self.make_drop_target(view));
         }
-        if (prev_widget_count != widget_count)
-            tui.refresh_hover(@src());
     }
 
     fn update_tab_buffers(self: *Self) !bool {