[elpa] externals/exwm cff02333e2 01/14: Don't assume that exwm--connection is non-nil

[ELPA Syncer]

branch: externals/exwm
commit cff02333e282c692aa685d57cc2b7c32419fffe2
Author: Nacho Barrientos <nacho.barrientos@cern.ch>
Commit: Adrián Medraño Calvo <adrian@medranocalvo.com>

    Don't assume that exwm--connection is non-nil
    
    `exwm-input--exit` could be called (via `exwm-exit`) from `exwm-init`
    in case of error when initialising EXWM. It could happen that the bit
    that failed when exwm-init is executed was the call to `xcb:connect`,
    hence `exwm--connection` would be nil when errors are handled (and
    `exwm-exit` is called).
    
    Without this patch, in the case above, the user will see a crash as
    there's no method allowing a nil XCB connection object:
    
      Debugger entered--Lisp error:
      (cl-no-applicable-method xcb:-+request nil #<xcb:SetInputFocus ...
    
    even worse, not even giving the chance to the `warn` call in
    `exwm-init`'s error handler to actually inform the user about the
    actual problem ("[XELB] Connection timeout", for instance).
    
    * exwm-input.el (exwm-input--exit): Check `exwm--connection' is
    set before trying to send requests.
---
 exwm-input.el | 13 +++++++------
 1 file changed, 7 insertions(+), 6 deletions(-)

diff --git a/exwm-input.el b/exwm-input.el
index 79bc78ef0f..2c65116aa3 100644
--- a/exwm-input.el
+++ b/exwm-input.el
@@ -1215,12 +1215,13 @@ One use is to access the keymap bound to KEYS (as 
prefix keys) in char-mode."
   (when exwm-input--update-focus-timer
     (cancel-timer exwm-input--update-focus-timer))
   ;; Make input focus working even without a WM.
-  (xcb:+request exwm--connection
-      (make-instance 'xcb:SetInputFocus
-                     :revert-to xcb:InputFocus:PointerRoot
-                     :focus exwm--root
-                     :time xcb:Time:CurrentTime))
-  (xcb:flush exwm--connection))
+  (when exwm--connection
+    (xcb:+request exwm--connection
+        (make-instance 'xcb:SetInputFocus
+                       :revert-to xcb:InputFocus:PointerRoot
+                       :focus exwm--root
+                       :time xcb:Time:CurrentTime))
+    (xcb:flush exwm--connection)))