Fix frame focus redirection with shared minibuffer windows (Bug#24500)

* src/frame.c (do_switch_frame): Redirect frame focus also when
the frame switched to has its minibuffer window on the selected
frame.
* src/window.c (candidate_window_p): To qualify as candidate
it's not sufficient for the window's frame to just share the
minibuffer window - it must be active as well.

2 files changed, 10 insertions, 3 deletions

diff --git a/src/frame.c b/src/frame.c
index 45559b0be98..a1c2199d044 100644
--- a/src/frame.c
+++ b/src/frame.c
@@ -1160,7 +1160,12 @@ do_switch_frame (Lisp_Object frame, int track, int for_deletion, Lisp_Object nor
       if (FRAMEP (xfocus))
         {
           focus = FRAME_FOCUS_FRAME (XFRAME (xfocus));
-          if (FRAMEP (focus) && XFRAME (focus) == SELECTED_FRAME ())
+          if ((FRAMEP (focus) && XFRAME (focus) == SELECTED_FRAME ())
+              /* Redirect frame focus also when FRAME has its minibuffer
+                 window on the selected frame (see Bug#24500).  */
+              || (NILP (focus)
+                  && EQ (FRAME_MINIBUF_WINDOW (XFRAME (frame)),
+                         sf->selected_window)))
             Fredirect_frame_focus (xfocus, frame);
         }
     }
diff --git a/src/window.c b/src/window.c
index 753ebc16fbf..acbefcdad16 100644
--- a/src/window.c
+++ b/src/window.c
@@ -2377,8 +2377,10 @@ candidate_window_p (Lisp_Object window, Lisp_Object owindow,
             == FRAME_TERMINAL (XFRAME (selected_frame)));
     }
   else if (WINDOWP (all_frames))
-    candidate_p = (EQ (FRAME_MINIBUF_WINDOW (f), all_frames)
-                   || EQ (XWINDOW (all_frames)->frame, w->frame)
+    /*  To qualify as candidate, it's not sufficient for WINDOW's frame
+        to just share the minibuffer window - it must be active as well
+        (see Bug#24500).  */
+    candidate_p = (EQ (XWINDOW (all_frames)->frame, w->frame)
                    || EQ (XWINDOW (all_frames)->frame, FRAME_FOCUS_FRAME (f)));
   else if (FRAMEP (all_frames))
     candidate_p = EQ (all_frames, w->frame);