macos: add key binding for equalizing split sizes

src/Surface.zig

@@ -2458,6 +2458,12 @@ pub fn performBindingAction(self: *Surface, action: input.Binding.Action) !bool
             } else log.warn("runtime doesn't implement resizeSplit", .{});
         },
 
+        .equalize_splits => {
+            if (@hasDecl(apprt.Surface, "equalizeSplits")) {
+                self.rt_surface.equalizeSplits();
+            } else log.warn("runtime doesn't implement equalizeSplits", .{});
+        },
+
         .toggle_split_zoom => {
             if (@hasDecl(apprt.Surface, "toggleSplitZoom")) {
                 self.rt_surface.toggleSplitZoom();

src/apprt/embedded.zig

@@ -95,6 +95,9 @@ pub const App = struct {
         /// Resize the current split.
         resize_split: ?*const fn (SurfaceUD, input.SplitResizeDirection, u16) callconv(.C) void = null,
 
+        /// Equalize all splits in the current window
+        equalize_splits: ?*const fn (SurfaceUD) callconv(.C) void = null,
+
         /// Zoom the current split.
         toggle_split_zoom: ?*const fn (SurfaceUD) callconv(.C) void = null,
 
@@ -396,6 +399,15 @@ pub const Surface = struct {
         func(self.opts.userdata, direction, amount);
     }
 
+    pub fn equalizeSplits(self: *const Surface) void {
+        const func = self.app.opts.equalize_splits orelse {
+            log.info("runtime embedder does not support equalize splits", .{});
+            return;
+        };
+
+        func(self.opts.userdata);
+    }
+
     pub fn toggleSplitZoom(self: *const Surface) void {
         const func = self.app.opts.toggle_split_zoom orelse {
             log.info("runtime embedder does not support split zoom", .{});
@@ -1388,6 +1400,11 @@ pub const CAPI = struct {
         ptr.resizeSplit(direction, amount);
     }
 
+    /// Equalize the size of all splits in the current window.
+    export fn ghostty_surface_split_equalize(ptr: *Surface) void {
+        ptr.equalizeSplits();
+    }
+
     /// Invoke an action on the surface.
     export fn ghostty_surface_binding_action(
         ptr: *Surface,

src/config/Config.zig

@@ -1016,6 +1016,11 @@ pub fn default(alloc_gpa: Allocator) Allocator.Error!Config {
             .{ .key = .right, .mods = .{ .super = true, .ctrl = true } },
             .{ .resize_split = .{ .right, 10 } },
         );
+        try result.keybind.set.put(
+            alloc,
+            .{ .key = .equal, .mods = .{ .shift = true, .alt = true } },
+            .{ .equalize_splits = {} },
+        );
 
         // Inspector, matching Chromium
         try result.keybind.set.put(

src/input/Binding.zig

@@ -197,6 +197,9 @@ pub const Action = union(enum) {
     /// direction
     resize_split: SplitResizeParameter,
 
+    /// Equalize all splits in the current window
+    equalize_splits: void,
+
     /// Show, hide, or toggle the terminal inspector for the currently
     /// focused terminal.
     inspector: InspectorMode,