Fix substitute-command-keys for global binding lookup

The previous change forgot to account for the (rare) case of doing a
lookup for a global binding when a specific keymap is in force.

* lisp/help.el (substitute-command-keys): Redo lookup in global map if
lookup in specific map fails.
*
test/lisp/help-tests.el (help-tests-substitute-command-keys/keymap-change):
Add testcase for specific map overriding advertised-binding.

1 files changed, 5 insertions, 1 deletions

diff --git a/test/lisp/help-tests.el b/test/lisp/help-tests.el
index 6f1dcfa5b6b..0fcaacb6443 100644
--- a/test/lisp/help-tests.el
+++ b/test/lisp/help-tests.el
@@ -181,8 +181,12 @@ M-g M-c		switch-to-completions
 
 (ert-deftest help-tests-substitute-command-keys/keymap-change ()
   (with-substitute-command-keys-test
+   ;; Global binding should be found even if specifying a specific map
    (test "\\<minibuffer-local-must-match-map>\\[abort-recursive-edit]" "C-]")
-   (test "\\<emacs-lisp-mode-map>\\[eval-defun]" "C-M-x")))
+   (test "\\<emacs-lisp-mode-map>\\[eval-defun]" "C-M-x")
+   ;; Specific map overrides advertised-binding
+   (test "\\<undo-repeat-map>\\[undo]" "u")
+   (test "\\[undo]" "C-x u")))
 
 (defvar-keymap help-tests-remap-map
   :full t