emacs: deal with unused lexical arguments and variables

The previous commit switched to lexical-binding but without dealing
with the new warnings about unused lexical arguments and variables.

This commit deals with most of them, in most cases by either removing
leftover bindings that are actually unnecessary, or by marking certain
arguments as "known to be unused" by prefixing their names with "_".

In the case of the functions named `notmuch-show-insert-...' the
amount of silencing that is required is a bit extreme and we might
want to investigate if there is a better way.

In the case of `notmuch-mua-mail', ignoring CONTINUE means that we do
not fully follow the intended behavior described in `compose-mail's
doc-string.

1 files changed, 19 insertions, 19 deletions

diff --git a/emacs/notmuch-show.el b/emacs/notmuch-show.el
index 72e21d94..48374b38 100644
--- a/emacs/notmuch-show.el
+++ b/emacs/notmuch-show.el
@@ -517,7 +517,7 @@ message at DEPTH in the current thread."
   'face 'message-mml
   :supertype 'notmuch-button-type)
 
-(defun notmuch-show-insert-part-header (nth content-type declared-type
+(defun notmuch-show-insert-part-header (_nth content-type declared-type
 					    &optional name comment)
   (let ((base-label (concat (and name (concat name ": "))
 			    declared-type
@@ -624,7 +624,7 @@ will return nil if the CID is unknown or cannot be retrieved."
   (setq mm-html-inhibit-images nil))
 
 (defvar w3m-current-buffer) ;; From `w3m.el'.
-(defun notmuch-show--cid-w3m-retrieve (url &rest args)
+(defun notmuch-show--cid-w3m-retrieve (url &rest _args)
   ;; url includes the cid: prefix and is URL encoded (see RFC 2392).
   (let* ((cid (url-unhex-string (substring url 4)))
 	 (content-and-type
@@ -640,7 +640,7 @@ will return nil if the CID is unknown or cannot be retrieved."
   (mapcar (lambda (inner-part) (plist-get inner-part :content-type))
 	  (plist-get part :content)))
 
-(defun notmuch-show-insert-part-multipart/alternative (msg part content-type nth depth button)
+(defun notmuch-show-insert-part-multipart/alternative (msg part _content-type _nth depth _button)
   (let ((chosen-type (car (notmuch-multipart/alternative-choose
 			   msg (notmuch-show-multipart/*-to-list part))))
 	(inner-parts (plist-get part :content))
@@ -659,7 +659,7 @@ will return nil if the CID is unknown or cannot be retrieved."
       (indent-rigidly start (point) 1)))
   t)
 
-(defun notmuch-show-insert-part-multipart/related (msg part content-type nth depth button)
+(defun notmuch-show-insert-part-multipart/related (msg part _content-type _nth depth _button)
   (let ((inner-parts (plist-get part :content))
 	(start (point)))
     ;; Render the primary part.  FIXME: Support RFC 2387 Start header.
@@ -672,7 +672,7 @@ will return nil if the CID is unknown or cannot be retrieved."
       (indent-rigidly start (point) 1)))
   t)
 
-(defun notmuch-show-insert-part-multipart/signed (msg part content-type nth depth button)
+(defun notmuch-show-insert-part-multipart/signed (msg part _content-type _nth depth button)
   (when button
     (button-put button 'face 'notmuch-crypto-part-header))
   ;; Insert a button detailing the signature status.
@@ -688,7 +688,7 @@ will return nil if the CID is unknown or cannot be retrieved."
       (indent-rigidly start (point) 1)))
   t)
 
-(defun notmuch-show-insert-part-multipart/encrypted (msg part content-type nth depth button)
+(defun notmuch-show-insert-part-multipart/encrypted (msg part _content-type _nth depth button)
   (when button
     (button-put button 'face 'notmuch-crypto-part-header))
   ;; Insert a button detailing the encryption status.
@@ -706,10 +706,10 @@ will return nil if the CID is unknown or cannot be retrieved."
       (indent-rigidly start (point) 1)))
   t)
 
-(defun notmuch-show-insert-part-application/pgp-encrypted (msg part content-type nth depth button)
+(defun notmuch-show-insert-part-application/pgp-encrypted (_msg _part _content-type _nth _depth _button)
   t)
 
-(defun notmuch-show-insert-part-multipart/* (msg part content-type nth depth button)
+(defun notmuch-show-insert-part-multipart/* (msg part _content-type _nth depth _button)
   (let ((inner-parts (plist-get part :content))
 	(start (point)))
     ;; Show all of the parts.
@@ -720,7 +720,7 @@ will return nil if the CID is unknown or cannot be retrieved."
       (indent-rigidly start (point) 1)))
   t)
 
-(defun notmuch-show-insert-part-message/rfc822 (msg part content-type nth depth button)
+(defun notmuch-show-insert-part-message/rfc822 (msg part _content-type _nth depth _button)
   (let* ((message (car (plist-get part :content)))
 	 (body (car (plist-get message :body)))
 	 (start (point)))
@@ -737,7 +737,7 @@ will return nil if the CID is unknown or cannot be retrieved."
       (indent-rigidly start (point) 1)))
   t)
 
-(defun notmuch-show-insert-part-text/plain (msg part content-type nth depth button)
+(defun notmuch-show-insert-part-text/plain (msg part _content-type _nth depth button)
   ;; For backward compatibility we want to apply the text/plain hook
   ;; to the whole of the part including the part button if there is
   ;; one.
@@ -751,7 +751,7 @@ will return nil if the CID is unknown or cannot be retrieved."
 	(run-hook-with-args 'notmuch-show-insert-text/plain-hook msg depth))))
   t)
 
-(defun notmuch-show-insert-part-text/calendar (msg part content-type nth depth button)
+(defun notmuch-show-insert-part-text/calendar (msg part _content-type _nth _depth _button)
   (insert (with-temp-buffer
 	    (insert (notmuch-get-bodypart-text msg part notmuch-show-process-crypto))
 	    ;; notmuch-get-bodypart-text does no newline conversion.
@@ -775,8 +775,8 @@ will return nil if the CID is unknown or cannot be retrieved."
   t)
 
 ;; For backwards compatibility.
-(defun notmuch-show-insert-part-text/x-vcalendar (msg part content-type nth depth button)
-  (notmuch-show-insert-part-text/calendar msg part content-type nth depth button))
+(defun notmuch-show-insert-part-text/x-vcalendar (msg part _content-type _nth depth _button)
+  (notmuch-show-insert-part-text/calendar msg part nil nil depth nil))
 
 (when (version< emacs-version "25.3")
   ;; https://bugs.gnu.org/28350
@@ -792,7 +792,7 @@ will return nil if the CID is unknown or cannot be retrieved."
     ;; the first time).
     (require 'enriched)
     (cl-letf (((symbol-function 'enriched-decode-display-prop)
-	       (lambda (start end &optional param) (list start end))))
+	       (lambda (start end &optional _param) (list start end))))
       (notmuch-show-insert-part-*/* msg part content-type nth depth button))))
 
 (defun notmuch-show-get-mime-type-of-application/octet-stream (part)
@@ -850,7 +850,7 @@ will return nil if the CID is unknown or cannot be retrieved."
     (shr-insert-document dom)
     t))
 
-(defun notmuch-show-insert-part-*/* (msg part content-type nth depth button)
+(defun notmuch-show-insert-part-*/* (msg part content-type _nth _depth _button)
   ;; This handler _must_ succeed - it is the handler of last resort.
   (notmuch-mm-display-part-inline msg part content-type notmuch-show-process-crypto)
   t)
@@ -970,13 +970,13 @@ The function should take two parameters, PART and HIDE, and
 should return non-NIL if a header button should be inserted for
 this part.")
 
-(defun notmuch-show-insert-header-p (part hide)
+(defun notmuch-show-insert-header-p (part _hide)
   ;; Show all part buttons except for the first part if it is text/plain.
   (let ((mime-type (notmuch-show-mime-type part)))
     (not (and (string= mime-type "text/plain")
 	      (<= (plist-get part :id) 1)))))
 
-(defun notmuch-show-reply-insert-header-p-never (part hide)
+(defun notmuch-show-reply-insert-header-p-never (_part _hide)
   nil)
 
 (defun notmuch-show-reply-insert-header-p-trimmed (part hide)
@@ -1759,7 +1759,7 @@ marked as unread, i.e. the tag changes in
     (apply 'notmuch-show-tag-message
 	   (notmuch-tag-change-list notmuch-show-mark-read-tags unread))))
 
-(defun notmuch-show-seen-current-message (start end)
+(defun notmuch-show-seen-current-message (_start _end)
   "Mark the current message read if it is open.
 
 We only mark it read once: if it is changed back then that is a
@@ -1777,7 +1777,7 @@ user decision and we should not override it."
     ;; We need to redisplay to get window-start and window-end correct.
     (redisplay)
     (save-excursion
-      (condition-case err
+      (condition-case nil
 	  (funcall notmuch-show-mark-read-function (window-start) (window-end))
 	((debug error)
 	 (unless notmuch-show--seen-has-errored