(adjust_window_trailing_edge): Correctly distinguish

series vs parallel cases, even when window has no parent.

1 files changed, 20 insertions, 11 deletions

diff --git a/src/window.c b/src/window.c
index 9b303a05002..72fbc58e32a 100644
--- a/src/window.c
+++ b/src/window.c
@@ -4275,18 +4275,30 @@ adjust_window_trailing_edge (window, delta, horiz_flag)
 
   while (1)
     {
+      Lisp_Object first_parallel = Qnil;
+
       p = XWINDOW (window);
       parent = p->parent;
 
-      /* Make sure there is a following window.  */
-      if (NILP (parent)
-          && (horiz_flag ? 1
-              : NILP (XWINDOW (window)->next)))
+      if (NILP (XWINDOW (window)->next))
         {
           Fset_window_configuration (old_config);
           error ("No other window following this one");
         }
 
+      /* See if this level has windows in parallel in the specified
+         direction.  If so, set FIRST_PARALLEL to the first one.  */
+      if (horiz_flag)
+        {
+          if (! NILP (parent) && !NILP (XWINDOW (parent)->vchild))
+            first_parallel = XWINDOW (parent)->vchild;
+        }
+      else
+        {
+          if (! NILP (parent) && !NILP (XWINDOW (parent)->hchild))
+            first_parallel = XWINDOW (parent)->hchild;
+        }
+
       /* Don't make this window too small.  */
       if (XINT (CURSIZE (window)) + delta
           < (horiz_flag ? window_min_width : window_min_height))
@@ -4304,12 +4316,11 @@ adjust_window_trailing_edge (window, delta, horiz_flag)
                XINT (CURSIZE (window)) + delta);
 
       /* If this window has following siblings in the desired dimension,
-         make them smaller.
+         make them smaller, and exit the loop.
+
          (If we reach the top of the tree and can never do this,
          we will fail and report an error, above.)  */
-      if (horiz_flag
-          ? !NILP (XWINDOW (parent)->hchild)
-          : !NILP (XWINDOW (parent)->vchild))
+      if (NILP (first_parallel))
         {
           if (!NILP (XWINDOW (window)->next))
             {
@@ -4331,9 +4342,7 @@ adjust_window_trailing_edge (window, delta, horiz_flag)
       else
         /* Here we have a chain of parallel siblings, in the other dimension.
            Change the size of the other siblings.  */
-        for (child = (horiz_flag
-                      ? XWINDOW (parent)->vchild
-                      : XWINDOW (parent)->hchild);
+        for (child = first_parallel;
              ! NILP (child);
              child = XWINDOW (child)->next)
           if (! EQ (child, window))