Modify erc-mode-map in module definitions

* lisp/erc/erc-button.el (erc-button-mode, erc-button-enable,
erc-button-disable): Replace call to `erc-button-setup' with one to
`erc--modify-local-map'.  This means `erc-button-setup' is now dead
code from a client perspective.
* lisp/erc/erc-goodies.el (erc-irccontrols-enable,
erc-irccontrols-disable, erc-irccontrols-mode): Bind
`erc-toggle-interpret-controls' in module definition so it's only
available when the module is active.
* lisp/erc/erc-log.el (erc-log-mode, erc-log-enable, erc-log-disable):
Move top-level `define-key' into module definition.
* lisp/erc/erc-match.el (erc-match-mode, erc-match-enable,
erc-match-disable): Move top-level `define-key' into module
definition.
* lisp/erc/erc.el (erc-mode-map): Remove C-c C-c binding for
`erc-toggle-interpret-controls'.
(erc--modify-local-map): Add helper for global modules to use when
modifying `erc-mode-map'.
* test/lisp/erc/erc-tests.el (erc--modify-local-map): Add test.
Ensure modifications to `erc-mode-map' on loading `erc' and via
`erc-mode-hook' still work.  (Bug#60954.)

5 files changed, 29 insertions, 13 deletions

diff --git a/lisp/erc/erc-button.el b/lisp/erc/erc-button.el
index c28dddefa0e..1be56f5dc21 100644
--- a/lisp/erc/erc-button.el
+++ b/lisp/erc/erc-button.el
@@ -55,11 +55,11 @@
   ((add-hook 'erc-insert-modify-hook #'erc-button-add-buttons 'append)
    (add-hook 'erc-send-modify-hook #'erc-button-add-buttons 'append)
    (add-hook 'erc-complete-functions #'erc-button-next-function)
-   (add-hook 'erc-mode-hook #'erc-button-setup))
+   (erc--modify-local-map t "<backtab>" #'erc-button-previous))
   ((remove-hook 'erc-insert-modify-hook #'erc-button-add-buttons)
    (remove-hook 'erc-send-modify-hook #'erc-button-add-buttons)
    (remove-hook 'erc-complete-functions #'erc-button-next-function)
-   (remove-hook 'erc-mode-hook #'erc-button-setup)))
+   (erc--modify-local-map nil "<backtab>" #'erc-button-previous)))
 
 ;;; Variables
 
@@ -233,6 +233,8 @@ constituents.")
   "Internal variable used to keep track of whether we've added the
 global-level ERC button keys yet.")
 
+;; Maybe deprecate this function and `erc-button-keys-added' if they
+;; continue to go unused for a another version (currently 5.6).
 (defun erc-button-setup ()
   "Add ERC mode-level button movement keys.  This is only done once."
   ;; Add keys.
diff --git a/lisp/erc/erc-goodies.el b/lisp/erc/erc-goodies.el
index 7ca155ef9d0..7ff5b1aecdf 100644
--- a/lisp/erc/erc-goodies.el
+++ b/lisp/erc/erc-goodies.el
@@ -377,9 +377,11 @@ The value `erc-interpret-controls-p' must also be t for this to work."
 (define-erc-module irccontrols nil
   "This mode enables the interpretation of IRC control chars."
   ((add-hook 'erc-insert-modify-hook #'erc-controls-highlight)
-   (add-hook 'erc-send-modify-hook #'erc-controls-highlight))
+   (add-hook 'erc-send-modify-hook #'erc-controls-highlight)
+   (erc--modify-local-map t "C-c C-c" #'erc-toggle-interpret-controls))
   ((remove-hook 'erc-insert-modify-hook #'erc-controls-highlight)
-   (remove-hook 'erc-send-modify-hook #'erc-controls-highlight)))
+   (remove-hook 'erc-send-modify-hook #'erc-controls-highlight)
+   (erc--modify-local-map nil "C-c C-c" #'erc-toggle-interpret-controls)))
 
 (defun erc-controls-interpret (str)
    "Return a copy of STR after dealing with IRC control characters.
diff --git a/lisp/erc/erc-log.el b/lisp/erc/erc-log.el
index 2cb9031640d..a44437ddcf7 100644
--- a/lisp/erc/erc-log.el
+++ b/lisp/erc/erc-log.el
@@ -230,7 +230,8 @@ also be a predicate function.  To only log when you are not set away, use:
    ;; append, so that 'erc-initialize-log-marker runs first
    (add-hook 'erc-connect-pre-hook #'erc-log-setup-logging 'append)
    (dolist (buffer (erc-buffer-list))
-     (erc-log-setup-logging buffer)))
+     (erc-log-setup-logging buffer))
+   (erc--modify-local-map t "C-c C-l" #'erc-save-buffer-in-logs))
   ;; disable
   ((remove-hook 'erc-insert-post-hook #'erc-save-buffer-in-logs)
    (remove-hook 'erc-send-post-hook #'erc-save-buffer-in-logs)
@@ -241,9 +242,8 @@ also be a predicate function.  To only log when you are not set away, use:
    (remove-hook 'erc-part-hook #'erc-conditional-save-buffer)
    (remove-hook 'erc-connect-pre-hook #'erc-log-setup-logging)
    (dolist (buffer (erc-buffer-list))
-     (erc-log-disable-logging buffer))))
-
-(define-key erc-mode-map "\C-c\C-l" #'erc-save-buffer-in-logs)
+     (erc-log-disable-logging buffer))
+   (erc--modify-local-map nil "C-c C-l" #'erc-save-buffer-in-logs)))
 
 ;;; functionality referenced from erc.el
 (defun erc-log-setup-logging (buffer)
diff --git a/lisp/erc/erc-match.el b/lisp/erc/erc-match.el
index 52ee5c855f3..7ec9078d493 100644
--- a/lisp/erc/erc-match.el
+++ b/lisp/erc/erc-match.el
@@ -52,8 +52,10 @@ they are hidden or highlighted.  This is controlled via the variables
 `erc-current-nick-highlight-type'.  For all these highlighting types,
 you can decide whether the entire message or only the sending nick is
 highlighted."
-  ((add-hook 'erc-insert-modify-hook #'erc-match-message 'append))
-  ((remove-hook 'erc-insert-modify-hook #'erc-match-message)))
+  ((add-hook 'erc-insert-modify-hook #'erc-match-message 'append)
+   (erc--modify-local-map t "C-c C-k" #'erc-go-to-log-matches-buffer))
+  ((remove-hook 'erc-insert-modify-hook #'erc-match-message)
+   (erc--modify-local-map nil "C-c C-k" #'erc-go-to-log-matches-buffer)))
 
 ;; Remaining customizations
 
@@ -647,8 +649,6 @@ See `erc-log-match-format'."
 					(get-buffer (car buffer-cons))))))
     (switch-to-buffer buffer-name)))
 
-(define-key erc-mode-map "\C-c\C-k" #'erc-go-to-log-matches-buffer)
-
 (defun erc-hide-fools (match-type _nickuserhost _message)
  "Hide foolish comments.
 This function should be called from `erc-text-matched-hook'."
diff --git a/lisp/erc/erc.el b/lisp/erc/erc.el
index 017f72476b1..60fe0480412 100644
--- a/lisp/erc/erc.el
+++ b/lisp/erc/erc.el
@@ -1209,7 +1209,6 @@ which the local user typed."
     (define-key map [home] #'erc-bol)
     (define-key map "\C-c\C-a" #'erc-bol)
     (define-key map "\C-c\C-b" #'erc-switch-to-buffer)
-    (define-key map "\C-c\C-c" #'erc-toggle-interpret-controls)
     (define-key map "\C-c\C-d" #'erc-input-action)
     (define-key map "\C-c\C-e" #'erc-toggle-ctcp-autoresponse)
     (define-key map "\C-c\C-f" #'erc-toggle-flood-control)
@@ -1233,6 +1232,19 @@ which the local user typed."
     map)
   "ERC keymap.")
 
+(defun erc--modify-local-map (mode &rest bindings)
+  "Modify `erc-mode-map' on behalf of a global module.
+Add or remove `key-valid-p' BINDINGS when toggling MODE."
+  (declare (indent 1))
+  (while (pcase-let* ((`(,key ,def . ,rest) bindings)
+                      (existing (keymap-lookup erc-mode-map key)))
+           (if mode
+               (when (or (not existing) (eq existing #'undefined))
+                 (keymap-set erc-mode-map key def))
+             (when (eq existing def)
+               (keymap-unset erc-mode-map key t)))
+           (setq bindings rest))))
+
 ;; Faces
 
 ; Honestly, I have a horrible sense of color and the "defaults" below