feat: add NSAccessibility AXBoundsForRange patch for macOS Zoom cursor tracking

2026-02-22 23:31:08 +01:00
parent d404c84963
commit e6d6fc62fd
1 changed files with 130 additions and 0 deletions
--- a/patches/0001-ns-implement-AXBoundsForRange-for-macOS-Zoom-cursor-.patch
+++ b/patches/0001-ns-implement-AXBoundsForRange-for-macOS-Zoom-cursor-.patch
@@ -0,0 +1,130 @@
+From 23fd2004cb00908a37ad44d0c41a1ca223eb7c55 Mon Sep 17 00:00:00 2001
+From: Daneel <daneel@sukany.cz>
+Date: Sun, 22 Feb 2026 23:21:32 +0100
+Subject: [PATCH] ns: implement AXBoundsForRange for macOS Zoom cursor tracking
+
+Add NSAccessibilityBoundsForRangeParameterizedAttribute support to
+EmacsView so that macOS Zoom and other accessibility tools can track
+the text cursor position.
+
+This implements accessibilityAttributeValue:forParameter: on EmacsView,
+storing the cursor rect in ns_draw_window_cursor and converting it to
+screen coordinates on demand.
+
+Changes:
+- Add lastAccessibilityCursorRect ivar to EmacsView (nsterm.h)
+- Store cursor rect in ns_draw_window_cursor (nsterm.m)
+- Implement accessibilityParameterizedAttributeNames
+- Implement accessibilityAttributeValue:forParameter: for BoundsForRange
+- Implement accessibilityIsIgnored, accessibilityFocusedUIElement, accessibilityRole
+- EmacsView reports as NSAccessibilityTextAreaRole
+
+See also: https://github.com/nicowillis/Ghostty/issues/4053
+---
+ src/nsterm.h |  3 +++
+ src/nsterm.m | 68 ++++++++++++++++++++++++++++++++++++++++++++++++++++
+ 2 files changed, 71 insertions(+)
+
+diff --git a/src/nsterm.h b/src/nsterm.h
+index 7c1ee4c..6c1ff34 100644
+--- a/src/nsterm.h
+++ b/src/nsterm.h
+@@ -485,6 +485,9 @@ enum ns_return_frame_mode
+   struct frame *emacsframe;
+   int scrollbarsNeedingUpdate;
+   NSRect ns_userRect;
+#ifdef NS_IMPL_COCOA
+  NSRect lastAccessibilityCursorRect;
+#endif
+ }
+ 
+ /* AppKit-side interface.  */
+diff --git a/src/nsterm.m b/src/nsterm.m
+index 932d209..c900d71 100644
+--- a/src/nsterm.m
+++ b/src/nsterm.m
+@@ -3232,6 +3232,15 @@ Note that CURSOR_WIDTH is meaningful only for (h)bar cursors.
+   /* Prevent the cursor from being drawn outside the text area.  */
+   r = NSIntersectionRect (r, ns_row_rect (w, glyph_row, TEXT_AREA));
+ 
+#ifdef NS_IMPL_COCOA
+  /* Store cursor rect for accessibility (AXBoundsForRange).  */
+  {
+    EmacsView *view = FRAME_NS_VIEW (f);
+    if (view)
+      view->lastAccessibilityCursorRect = r;
+  }
+#endif
+
+   ns_focus (f, NULL, 0);
+ 
+   NSGraphicsContext *ctx = [NSGraphicsContext currentContext];
+@@ -9474,6 +9483,65 @@ - (int) fullscreenState
+   return fs_state;
+ }
+ 
+#ifdef NS_IMPL_COCOA
+/* Accessibility support for macOS Zoom and other assistive tools.
+   Implements AXBoundsForRange so that cursor tracking works.  */
+
+- (BOOL)accessibilityIsIgnored
+{
+  return NO;
+}
+
+- (id)accessibilityFocusedUIElement
+{
+  return self;
+}
+
+- (NSString *)accessibilityRole
+{
+  return NSAccessibilityTextAreaRole;
+}
+
+- (NSArray *)accessibilityParameterizedAttributeNames
+{
+  NSArray *superAttrs = [super accessibilityParameterizedAttributeNames];
+  if (superAttrs == nil)
+    superAttrs = @[];
+  return [superAttrs arrayByAddingObjectsFromArray:
+	    @[NSAccessibilityBoundsForRangeParameterizedAttribute]];
+}
+
+- (id)accessibilityAttributeValue:(NSString *)attribute
+		     forParameter:(id)parameter
+{
+  if ([attribute isEqualToString:
+	 NSAccessibilityBoundsForRangeParameterizedAttribute])
+    {
+      NSRect viewRect = lastAccessibilityCursorRect;
+
+      /* lastAccessibilityCursorRect is in EmacsView coordinates
+	 (flipped: y=0 at top).  convertRect:toView:nil handles
+	 the flipped-to-unflipped conversion automatically for
+	 flipped views, so no manual flip is needed.  */
+
+      if (viewRect.size.width < 1)
+	viewRect.size.width = 1;
+      if (viewRect.size.height < 1)
+	viewRect.size.height = 8;
+
+      NSWindow *win = [self window];
+      if (win == nil)
+	return [NSValue valueWithRect:NSZeroRect];
+
+      NSRect windowRect = [self convertRect:viewRect toView:nil];
+      NSRect screenRect = [win convertRectToScreen:windowRect];
+
+      return [NSValue valueWithRect:screenRect];
+    }
+  return [super accessibilityAttributeValue:attribute forParameter:parameter];
+}
+#endif /* NS_IMPL_COCOA */
+
+ @end  /* EmacsView */
+ 
+ 
+-- 
+2.43.0
+