Obsolete gnus-remove-if and gnus-remove-if-not

Use seq-remove and seq-filter, respectively, instead.

* lisp/gnus/gnus-util.el: Remove functions and replace with
  define-obsolete-function-alias calls.
* lisp/gnus/gnus.el: Require seq here.
* lisp/gnus/gnus-art.el (gnus-mime-view-part-as-type):
* lisp/gnus/gnus-icalendar.el (gnus-icalendar-event--get-attendee-names):
* lisp/gnus/gnus-score.el (gnus-summary-score-effect):
* lisp/gnus/gnus-sum.el (gnus-read-move-group-name):
* lisp/gnus/gnus-topic.el (gnus-group-prepare-topics):
* lisp/gnus/gnus-win.el (gnus-get-buffer-window):
* lisp/gnus/nnmail.el (nnmail-purge-split-history):
* lisp/gnus/nnmaildir.el (nnmaildir-request-scan):
* lisp/gnus/nnrss.el (nnrss-make-hash-index): Replace calls in all
  these locations.

lisp/gnus/gnus-art.el

@@ -5219,7 +5219,7 @@ available media-types."
 	    (gnus-completing-read
 	     "View as MIME type"
 	     (if pred
-		 (gnus-remove-if-not pred (mailcap-mime-types))
+		 (seq-filter pred (mailcap-mime-types))
 	       (mailcap-mime-types))
 	     nil nil nil
 	     (car default)))))

lisp/gnus/gnus-icalendar.el

@@ -169,7 +169,7 @@
 
 (defun gnus-icalendar-event--get-attendee-names (ical)
   (let* ((event (car (icalendar--all-events ical)))
-         (attendee-props (gnus-remove-if-not
+         (attendee-props (seq-filter
                           (lambda (p) (eq (car p) 'ATTENDEE))
                           (caddr event))))
 
@@ -180,7 +180,7 @@
 	  (or (plist-get (cadr prop) 'CN)
 	      (replace-regexp-in-string "^.*MAILTO:" "" (caddr prop))))
 	 (attendees-by-type (type)
-			    (gnus-remove-if-not
+			    (seq-filter
 			     (lambda (p) (string= (attendee-role p) type))
 			     attendee-props))
 	 (attendee-names-by-type

lisp/gnus/gnus-score.el

@@ -921,7 +921,7 @@ EXTRA is the possible non-standard header."
   (interactive (list (gnus-completing-read "Header"
                                            (mapcar
                                             'car
-                                            (gnus-remove-if-not
+                                            (seq-filter
                                              (lambda (x) (fboundp (nth 2 x)))
                                              gnus-header-index))
                                            t)

lisp/gnus/gnus-sum.el

@@ -12270,21 +12270,27 @@ save those articles instead."
 		  (if (> (length articles) 1)
 		      (format "these %d articles" (length articles))
 		    "this article")))
+	 valid-names
 	 (to-newsgroup
-          (cond
-           ((null split-name)
-            (gnus-group-completing-read
-             prom
-             (gnus-remove-if-not 'gnus-valid-move-group-p gnus-active-hashtb t)
-             nil prefix nil default))
-           ((= 1 (length split-name))
-            (gnus-group-completing-read
-             prom
-	     (gnus-remove-if-not 'gnus-valid-move-group-p gnus-active-hashtb t)
-             nil prefix 'gnus-group-history (car split-name)))
-           (t
-            (gnus-completing-read
-             prom (nreverse split-name) nil nil 'gnus-group-history))))
+	  (progn
+	    (mapatoms (lambda (g)
+			(when (gnus-valid-move-group-p g)
+			  (push g valid-names)))
+		      gnus-active-hashtb)
+            (cond
+             ((null split-name)
+              (gnus-group-completing-read
+               prom
+               valid-names
+               nil prefix nil default))
+             ((= 1 (length split-name))
+              (gnus-group-completing-read
+               prom
+	       valid-names
+               nil prefix 'gnus-group-history (car split-name)))
+             (t
+              (gnus-completing-read
+               prom (nreverse split-name) nil nil 'gnus-group-history)))))
          (to-method (gnus-server-to-method (gnus-group-method to-newsgroup)))
 	 encoded)
     (when to-newsgroup

lisp/gnus/gnus-topic.el

@@ -460,7 +460,7 @@ If LOWEST is non-nil, list all newsgroups of level LOWEST or higher."
 	(unless gnus-killed-hashtb
 	  (gnus-make-hashtable-from-killed))
 	(gnus-group-prepare-flat-list-dead
-	 (gnus-remove-if (lambda (group)
+	 (seq-remove (lambda (group)
 			   (or (gnus-group-entry group)
 			       (gnus-gethash group gnus-killed-hashtb)))
 			 not-in-list)

lisp/gnus/gnus-util.el

@@ -1117,41 +1117,9 @@ ARG is passed to the first function."
        (with-current-buffer gnus-group-buffer
 	 (eq major-mode 'gnus-group-mode))))
 
-(defun gnus-remove-if (predicate sequence &optional hash-table-p)
-  "Return a copy of SEQUENCE with all items satisfying PREDICATE removed.
-SEQUENCE should be a list, a vector, or a string.  Returns always a list.
-If HASH-TABLE-P is non-nil, regards SEQUENCE as a hash table."
-  (let (out)
-    (if hash-table-p
-	(mapatoms (lambda (symbol)
-		    (unless (funcall predicate symbol)
-		      (push symbol out)))
-		  sequence)
-      (unless (listp sequence)
-	(setq sequence (append sequence nil)))
-      (while sequence
-	(unless (funcall predicate (car sequence))
-	  (push (car sequence) out))
-	(setq sequence (cdr sequence))))
-    (nreverse out)))
+(define-obsolete-function-alias 'gnus-remove-if 'seq-remove "27.1")
 
-(defun gnus-remove-if-not (predicate sequence &optional hash-table-p)
-  "Return a copy of SEQUENCE with all items not satisfying PREDICATE removed.
-SEQUENCE should be a list, a vector, or a string.  Returns always a list.
-If HASH-TABLE-P is non-nil, regards SEQUENCE as a hash table."
-  (let (out)
-    (if hash-table-p
-	(mapatoms (lambda (symbol)
-		    (when (funcall predicate symbol)
-		      (push symbol out)))
-		  sequence)
-      (unless (listp sequence)
-	(setq sequence (append sequence nil)))
-      (while sequence
-	(when (funcall predicate (car sequence))
-	  (push (car sequence) out))
-	(setq sequence (cdr sequence))))
-    (nreverse out)))
+(define-obsolete-function-alias 'gnus-remove-if-not 'seq-filter "27.1")
 
 (defun gnus-grep-in-list (word list)
   "Find if a WORD matches any regular expression in the given LIST."

lisp/gnus/gnus-win.el

@@ -513,7 +513,7 @@ should have point."
 	      (memq frame '(t 0 visible)))
 	 (car
 	  (let ((frames (frames-on-display-list)))
-	    (gnus-remove-if (lambda (win) (not (memq (window-frame win)
+	    (seq-remove (lambda (win) (not (memq (window-frame win)
 						     frames)))
 			    (get-buffer-window-list buffer nil frame)))))
 	(t

lisp/gnus/gnus.el

@@ -33,6 +33,7 @@
 (require 'wid-edit)
 (require 'mm-util)
 (require 'nnheader)
+(require 'seq)
 
 ;; These are defined afterwards with gnus-define-group-parameter
 (defvar gnus-ham-process-destinations)

lisp/gnus/nnmail.el

@@ -2034,7 +2034,7 @@ If TIME is nil, then return the cutoff time for oldness instead."
   "Remove all instances of GROUP from `nnmail-split-history'."
   (let ((history nnmail-split-history))
     (while history
-      (setcar history (gnus-remove-if (lambda (e) (string= (car e) group))
+      (setcar history (seq-remove (lambda (e) (string= (car e) group))
 				      (car history)))
       (pop history))
     (setq nnmail-split-history (delq nil nnmail-split-history))))

lisp/gnus/nnmaildir.el

@@ -915,7 +915,7 @@ This variable is set by `nnmaildir-request-article'.")
 	    (setq dirs (funcall srv-ls srv-dir nil "\\`[^.]" 'nosort)
 		  dirs (if (zerop (length target-prefix))
 			   dirs
-			 (gnus-remove-if
+			 (seq-remove
 			  (lambda (dir)
 			    (and (>= (length dir) (length target-prefix))
 				 (string= (substring dir 0

lisp/gnus/nnrss.el

@@ -625,7 +625,7 @@ which RSS 2.0 allows."
 ;;; Snarf functions
 (defun nnrss-make-hash-index (item)
   (gnus-message 9 "nnrss: Making hash index of %s" (gnus-prin1-to-string item))
-  (setq item (gnus-remove-if
+  (setq item (seq-remove
 	      (lambda (field)
 		(when (listp field)
 		  (memq (car field) nnrss-ignore-article-fields)))