Stop message.el from loading about 40 libraries it doesn't always need.

The general approach is to autoload rather than require, and to
require in the specific functions rather than the file.  (Bug#5642)

* url/url.el: Move mailcap require earlier in the file.

* gnus/gmm-utils.el: Don't require wid-edit.
(widget-create-child-value, widget-convert, widget-default-get):
Autoload.

* gnus/gnus-util.el: Don't require time-date, netrc.
(message-fetch-field, gnus-group-name-decode): Declare rather than
autoloading.
(gnus-fetch-field): Require message.
(gnus-decode-newsgroups): Require gnus-group.

* gnus/ietf-drums.el: Don't require time-date.

* gnus/message.el: Don't require hashcash, canlock, ecomplete.
Do require mail-utils.  Require nnheader only when compiling.
(smtpmail-default-smtp-server): Remove declaration.
(message-send-mail-function): Check smtpmail-default-smtp-server
is bound rather than requiring smtpmail.
(message-auto-save-directory, message-insert-signature): Use
expand-file-name rather than nnheader-concat.
(nnheader-insert-file-contents): Autoload.
(hashcash-wait-async): Declare.
(message-send-mail): Only call gnus-setup-posting-charset if
gnus-group-posting-charset-alist is bound.  Require hashcash if needed.
(message-send-mail-with-sendmail): Require sendmail.
(canlock-password, canlock-password-for-verify): Declare.
(message-canlock-password): Require canlock.
(nnheader-get-report): Autoload.
(gnus-setup-posting-charset): Declare.
(message-send-news): Require gnus-msg.
(message-make-references, message-make-in-reply-to): Use mail-header-id
rather than the alias mail-header-message-id.
(ecomplete-add-item, ecomplete-save): Declare.
(message-put-addresses-in-ecomplete): Require ecomplete.
(ecomplete-display-matches): Autoload.

* gnus/mm-decode.el: Don't require mailcap, gnus-util.
(gnus-map-function, gnus-replace-in-string, gnus-read-shell-command)
(message-fetch-field, mailcap-parse-mailcaps, mailcap-mime-info):
Autoload.
(mailcap-mime-extensions): Declare.

* gnus/mm-encode.el: Don't require mailcap.
(mailcap-extension-to-mime): Autoload.

* gnus/mml-sec.el: Don't require password-cache.

* gnus/mml.el (gnus-setup-posting-charset): Declare rather than autoload.
(mailcap-parse-mimetypes, mailcap-mime-types): Declare.
(mml-minibuffer-read-type): Require mailcap.
(mml-preview): Require gnus-msg.

* gnus/mml1991.el: Require password-cache.
(password-cache-expiry): Remove declaration.

* gnus/mml2015.el: Require password-cache.
(password-cache-expiry): Remove declaration.

* gnus/nneething.el (mailcap): Require mailcap.

* gnus/nnheader.el: (declare-function): Add compatibility stub.
(message-remove-header): Declare rather than autoload.
(nnheader-replace-header): Require message.

* gnus/nnimap.el (declare-function): Add compatibility stub.
(netrc-parse, netrc-machine-user-or-password): Declare.
(nnimap-open-connection): Require netrc.

* gnus/nntp.el (declare-function): Add compatibility stub.
(netrc-parse, netrc-machine, netrc-get): Declare.
(nntp-send-authinfo): Require netrc.

* gnus/rfc2047.el: Don't require qp.
(quoted-printable-encode-region, quoted-printable-decode-string):
Autoload.

* gnus/sieve-mode.el: Don't require easymenu.
(easy-menu-add-item): Autoload it.

* gnus/spam-stat.el (time-to-number-of-days): Autoload it.

* password-cache.el (password-cache, password-cache-expiry):
Autoload.

1 files changed, 44 insertions, 15 deletions

diff --git a/lisp/gnus/message.el b/lisp/gnus/message.el
index d255e3410bd..abdc163bb16 100644
--- a/lisp/gnus/message.el
+++ b/lisp/gnus/message.el
@@ -34,11 +34,12 @@
 (eval-when-compile
   (require 'cl))
 
-(require 'hashcash)
-(require 'canlock)
 (require 'mailheader)
 (require 'gmm-utils)
-(require 'nnheader)
+(require 'mail-utils)
+;; Only for the trivial macros mail-header-from, mail-header-date
+;; mail-header-references, mail-header-subject, mail-header-id
+(eval-when-compile (require 'nnheader))
 ;; This is apparently necessary even though things are autoloaded.
 ;; Because we dynamically bind mail-abbrev-mode-regexp, we'd better
 ;; require mailabbrev here.
@@ -48,7 +49,6 @@
 (require 'mail-parse)
 (require 'mml)
 (require 'rfc822)
-(require 'ecomplete)
 
 (autoload 'mailclient-send-it "mailclient") ;; Emacs 22 or contrib/
 
@@ -655,8 +655,6 @@ Done before generating the new subject of a forward."
   :link '(custom-manual "(message)Canceling News")
   :type 'string)
 
-(defvar smtpmail-default-smtp-server)
-
 (defun message-send-mail-function ()
   "Return suitable value for the variable `message-send-mail-function'."
   (cond ((and (require 'sendmail)
@@ -665,14 +663,13 @@ Done before generating the new subject of a forward."
 	      (executable-find sendmail-program))
 	 'message-send-mail-with-sendmail)
 	((and (locate-library "smtpmail")
-	      (require 'smtpmail)
+	      (boundp 'smtpmail-default-smtp-server)
 	      smtpmail-default-smtp-server)
 	 'message-smtpmail-send-it)
 	((locate-library "mailclient")
 	 'message-send-mail-with-mailclient)
 	(t
-	 (lambda ()
-	   (error "Don't know how to send mail.  Please customize `message-send-mail-function'")))))
+	 (error "Don't know how to send mail.  Please customize `message-send-mail-function'"))))
 
 ;; Useful to set in site-init.el
 (defcustom message-send-mail-function
@@ -1282,7 +1279,7 @@ text and it replaces `self-insert-command' with the other command, e.g.
   :type '(repeat function))
 
 (defcustom message-auto-save-directory
-  (file-name-as-directory (nnheader-concat message-directory "drafts"))
+  (file-name-as-directory (expand-file-name "drafts" message-directory))
   "*Directory where Message auto-saves buffers if Gnus isn't running.
 If nil, Message won't auto-save."
   :group 'message-buffers
@@ -1958,6 +1955,8 @@ is used by default."
 		 (setq paren nil))))
 	(nreverse elems)))))
 
+(autoload 'nnheader-insert-file-contents "nnheader")
+
 (defun message-mail-file-mbox-p (file)
   "Say whether FILE looks like a Unix mbox file."
   (when (and (file-exists-p file)
@@ -3410,8 +3409,8 @@ Message buffers and is not meant to be called directly."
 				;; if message-signature-file contains a path.
 				(not (file-name-directory
 				      message-signature-file)))
-			   (nnheader-concat message-signature-directory
-					    message-signature-file)
+			   (expand-file-name message-signature-file
+					     message-signature-directory)
 			 message-signature-file))
 		 (file-exists-p signature-file))))
     (when signature
@@ -4414,6 +4413,8 @@ This function could be useful in `message-setup-hook'."
 	    (erase-buffer)))
       (kill-buffer tembuf))))
 
+(declare-function hashcash-wait-async "hashcash" (&optional buffer))
+
 (defun message-send-mail (&optional arg)
   (require 'mail-utils)
   (let* ((tembuf (message-generate-new-buffer-clone-locals " message temp"))
@@ -4421,14 +4422,26 @@ This function could be useful in `message-setup-hook'."
 	 (news (message-news-p))
 	 (mailbuf (current-buffer))
 	 (message-this-is-mail t)
+	 ;; gnus-setup-posting-charset is autoloaded in mml.el (FIXME
+	 ;; maybe it should not be), which this file requires.  Hence
+	 ;; the fboundp test is always true.  Loading it from gnus-msg
+	 ;; loads many Gnus files (Bug#5642).  If
+	 ;; gnus-group-posting-charset-alist hasn't been customized,
+	 ;; this is just going to return nil anyway.  FIXME it would
+	 ;; be good to improve this further, because even if g-g-p-c-a
+	 ;; has been customized, that is likely to just be for news.
+	 ;; Eg either move the definition from gnus-msg, or separate out
+	 ;; the mail and news parts.
 	 (message-posting-charset
-	  (if (fboundp 'gnus-setup-posting-charset)
+	  (if (and (fboundp 'gnus-setup-posting-charset)
+		   (boundp 'gnus-group-posting-charset-alist))
 	      (gnus-setup-posting-charset nil)
 	    message-posting-charset))
 	 (headers message-required-mail-headers))
     (when (and message-generate-hashcash
 	       (not (eq message-generate-hashcash 'opportunistic)))
       (message "Generating hashcash...")
+      (require 'hashcash)
       ;; Wait for calculations already started to finish...
       (hashcash-wait-async)
       ;; ...and do calculations not already done.  mail-add-payment
@@ -4550,6 +4563,7 @@ If you always want Gnus to send messages in one piece, set
 
 (defun message-send-mail-with-sendmail ()
   "Send off the prepared buffer with sendmail."
+  (require 'sendmail)
   (let ((errbuf (if message-interactive
 		    (message-generate-new-buffer-clone-locals
 		     " sendmail errors")
@@ -4713,10 +4727,14 @@ Do not use this for anything important, it is cryptographically weak."
 		  (prin1-to-string (recent-keys))
 		  (prin1-to-string (garbage-collect))))))
 
+(defvar canlock-password)
+(defvar canlock-password-for-verify)
+
 (defun message-canlock-password ()
   "The password used by message for cancel locks.
 This is the value of `canlock-password', if that option is non-nil.
 Otherwise, generate and save a value for `canlock-password' first."
+  (require 'canlock)
   (unless canlock-password
     (customize-save-variable 'canlock-password (message-canlock-generate))
     (setq canlock-password-for-verify canlock-password))
@@ -4727,7 +4745,12 @@ Otherwise, generate and save a value for `canlock-password' first."
     (message-canlock-password)
     (canlock-insert-header)))
 
+(autoload 'nnheader-get-report "nnheader")
+
+(declare-function gnus-setup-posting-charset "gnus-msg" (group))
+
 (defun message-send-news (&optional arg)
+  (require 'gnus-msg)
   (let* ((tembuf (message-generate-new-buffer-clone-locals " *message temp*"))
 	 (case-fold-search nil)
 	 (method (if (functionp message-post-method)
@@ -5466,7 +5489,7 @@ In posting styles use `(\"Expires\" (make-expires-date 30))'."
 (defun message-make-references ()
   "Return the References header for this message."
   (when message-reply-headers
-    (let ((message-id (mail-header-message-id message-reply-headers))
+    (let ((message-id (mail-header-id message-reply-headers))
 	  (references (mail-header-references message-reply-headers)))
       (if (or references message-id)
 	  (concat (or references "") (and references " ")
@@ -5478,7 +5501,7 @@ In posting styles use `(\"Expires\" (make-expires-date 30))'."
   (when message-reply-headers
     (let ((from (mail-header-from message-reply-headers))
 	  (date (mail-header-date message-reply-headers))
-	  (msg-id (mail-header-message-id message-reply-headers)))
+	  (msg-id (mail-header-id message-reply-headers)))
       (when from
 	(let ((name (mail-extract-address-components from)))
 	  (concat
@@ -8003,7 +8026,11 @@ From headers in the original article."
 	(not result)
       result)))
 
+(declare-function ecomplete-add-item "ecomplete" (type key text))
+(declare-function ecomplete-save "ecomplete" ())
+
 (defun message-put-addresses-in-ecomplete ()
+  (require 'ecomplete)
   (dolist (header '("to" "cc" "from" "reply-to"))
     (let ((value (message-field-value header)))
       (dolist (string (mail-header-parse-addresses value 'raw))
@@ -8014,6 +8041,8 @@ From headers in the original article."
 			    string))))
   (ecomplete-save))
 
+(autoload 'ecomplete-display-matches "ecomplete")
+
 (defun message-display-abbrev (&optional choose)
   "Display the next possible abbrev for the text before point."
   (interactive (list t))