From 10a9ce1ed282e29bbc65065956689ebf5bad0919 Mon Sep 17 00:00:00 2001
From: Michael Grant <mgrant@grant.org>
Date: Fri, 20 Mar 2026 07:59:25 +0000
Subject: [PATCH] Prohibit swapping 2 floating panes, that doesn't make sense.

---
 cmd-swap-pane.c | 12 ++++++++++++
 layout.c        |  4 ++++
 2 files changed, 16 insertions(+)

diff --git a/cmd-swap-pane.c b/cmd-swap-pane.c
index 7271e50e..f0238e24 100644
--- a/cmd-swap-pane.c
+++ b/cmd-swap-pane.c
@@ -79,6 +79,11 @@ cmd_swap_pane_exec(struct cmd *self, struct cmdq_item *item)
 	if (src_wp == dst_wp)
 		goto out;
 
+	if ((src_wp->flags & PANE_FLOATING) && (dst_wp->flags & PANE_FLOATING)) {
+		cmdq_error(item, "cannot swap two floating panes");
+		return (CMD_RETURN_ERROR);
+	}
+
 	server_client_remove_pane(src_wp);
 	server_client_remove_pane(dst_wp);
 
@@ -99,6 +104,13 @@ cmd_swap_pane_exec(struct cmd *self, struct cmdq_item *item)
 	dst_lc->wp = src_wp;
 	src_wp->layout_cell = dst_lc;
 
+	/* Swap PANE_FLOATING flag to keep each pane consistent with its new
+	 * layout cell (floating cells have parent == NULL). */
+	if ((src_wp->flags ^ dst_wp->flags) & PANE_FLOATING) {
+		src_wp->flags ^= PANE_FLOATING;
+		dst_wp->flags ^= PANE_FLOATING;
+	}
+
 	src_wp->window = dst_w;
 	options_set_parent(src_wp->options, dst_w->options);
 	src_wp->flags |= (PANE_STYLECHANGED|PANE_THEMECHANGED);
diff --git a/layout.c b/layout.c
index ca85a7af..c2811f1e 100644
--- a/layout.c
+++ b/layout.c
@@ -301,6 +301,8 @@ layout_cell_is_top(struct window *w, struct layout_cell *lc)
 
 	while (lc != w->layout_root) {
 		next = lc->parent;
+		if (next == NULL)
+			return (0);
 		if (next->type == LAYOUT_TOPBOTTOM &&
 		    lc != TAILQ_FIRST(&next->cells))
 			return (0);
@@ -317,6 +319,8 @@ layout_cell_is_bottom(struct window *w, struct layout_cell *lc)
 
 	while (lc != w->layout_root) {
 		next = lc->parent;
+		if (next == NULL)
+			return (0);
 		if (next->type == LAYOUT_TOPBOTTOM &&
 		    lc != TAILQ_LAST(&next->cells, layout_cells))
 			return (0);