Make goto-line keep a separate input history per buffer

* lisp/simple.el (goto-line-history): New history variable.
(goto-line): Use new (buffer-local) variable as input
history (Bug#38282).
* lisp/subr.el (read-number-history): New history variable.
(read-number): Use the new variable as default input history.
* doc/lispref/minibuf.texi (Minibuffer History): Document
read-number-history and goto-line-history variables.
* etc/NEWS: Announce changes.

doc/lispref/minibuf.texi

@@ -645,6 +645,15 @@ A history list for variable-name arguments read by
 @code{read-variable}.
 @end defvar
 
+@defvar read-number-history
+A history list for numbers read by @code{read-number}.
+@end defvar
+
+@defvar goto-line-history
+A history list for arguments to @code{goto-line}.  This variable is
+buffer local.
+@end defvar
+
 @c Less common: coding-system-history, input-method-history,
 @c command-history, grep-history, grep-find-history,
 @c read-envvar-name-history, setenv-history, yes-or-no-p-history.

etc/NEWS

@@ -65,6 +65,17 @@ GNU General Public License for more details.
 You should have received a copy of the GNU General Public License
 along with GNU Emacs.  If not, see <https://www.gnu.org/licenses/>.
 
++++
+** 'read-number' now has its own history variable.
+Additionally, the function now accepts a HIST argument which can be
+used to specify a custom history variable.
+
++++
+** Input history for 'goto-line' is now local to every buffer.
+Each buffer will keep a separate history of line numbers used with
+'goto-line'.  This should help making faster the process of finding
+line numbers that were previously jumped to.
+
 
 Local variables:
 coding: utf-8

lisp/simple.el

@@ -1212,6 +1212,10 @@ that uses or sets the mark."
 
 ;; Counting lines, one way or another.
 
+(defvar goto-line-history nil
+  "History of values entered with `goto-line'.")
+(make-variable-buffer-local 'goto-line-history)
+
 (defun goto-line (line &optional buffer)
   "Go to LINE, counting from line 1 at beginning of buffer.
 If called interactively, a numeric prefix argument specifies
@@ -1256,7 +1260,8 @@ rather than line counts."
 	       "")))
        ;; Read the argument, offering that number (if any) as default.
        (list (read-number (format "Goto line%s: " buffer-prompt)
-                          (list default (line-number-at-pos)))
+                          (list default (line-number-at-pos))
+                          'goto-line-history)
 	     buffer))))
   ;; Switch to the desired buffer, one way or another.
   (if buffer

lisp/subr.el

@@ -2518,10 +2518,15 @@ by doing (clear-string STRING)."
               ;; And of course, don't keep the sensitive data around.
               (erase-buffer))))))))
 
-(defun read-number (prompt &optional default)
+(defvar read-number-history nil
+  "The default history for the `read-number' function.")
+
+(defun read-number (prompt &optional default hist)
   "Read a numeric value in the minibuffer, prompting with PROMPT.
 DEFAULT specifies a default value to return if the user just types RET.
 The value of DEFAULT is inserted into PROMPT.
+HIST specifies a history list variable.  See `read-from-minibuffer'
+for details of the HIST argument.
 This function is used by the `interactive' code letter `n'."
   (let ((n nil)
 	(default1 (if (consp default) (car default) default)))
@@ -2535,7 +2540,7 @@ This function is used by the `interactive' code letter `n'."
     (while
 	(progn
 	  (let ((str (read-from-minibuffer
-		      prompt nil nil nil nil
+		      prompt nil nil nil (or hist 'read-number-history)
 		      (when default
 			(if (consp default)
 			    (mapcar 'number-to-string (delq nil default))