From dc86c4cc0ba230c632b10cefb22b9fec1cd1d046 Mon Sep 17 00:00:00 2001
From: Juri Linkov <juri@linkov.net>
Date: Wed, 23 Sep 2020 22:39:32 +0300
Subject: [PATCH] New command goto-line-relative (bug#5042, bug#9917)
* lisp/simple.el (goto-line-read-args): New function with code from goto-line.
(goto-line): New arg RELATIVE. Also use 'widen-automatically' to
leave all lines accessible in the narrowed buffer.
(goto-line-relative): New command.
* lisp/info.el (Info-mode-map): Remap 'goto-line' to 'goto-line-relative'.
* doc/emacs/basic.texi (Moving Point):
* doc/emacs/display.texi (Optional Mode Line): Mention goto-line-relative.
---
doc/emacs/basic.texi | 5 ++-
doc/emacs/display.texi | 7 ++--
etc/NEWS | 7 ++++
lisp/info.el | 1 +
lisp/simple.el | 86 ++++++++++++++++++++++++++++--------------
5 files changed, 73 insertions(+), 33 deletions(-)
diff --git a/doc/emacs/basic.texi b/doc/emacs/basic.texi
index 444b2469cf1..cde7b475d95 100644
--- a/doc/emacs/basic.texi
+++ b/doc/emacs/basic.texi
@@ -311,13 +311,16 @@ Position 1 is the beginning of the buffer.
@kindex M-g M-g
@kindex M-g g
@findex goto-line
+@findex goto-line-relative
Read a number @var{n} and move point to the beginning of line number
@var{n} (@code{goto-line}). Line 1 is the beginning of the buffer. If
point is on or just after a number in the buffer, that is the default
for @var{n}. Just type @key{RET} in the minibuffer to use it. You can
also specify @var{n} by giving @kbd{M-g M-g} a numeric prefix argument.
@xref{Select Buffer}, for the behavior of @kbd{M-g M-g} when you give it
-a plain prefix argument.
+a plain prefix argument. Alternatively, you can use the command
+@code{goto-line-relative} to move point to the line relative to the
+accessible portion of the narrowed buffer.
@item M-g @key{TAB}
@kindex M-g TAB
diff --git a/doc/emacs/display.texi b/doc/emacs/display.texi
index e7b8745a044..6f1bc802b85 100644
--- a/doc/emacs/display.texi
+++ b/doc/emacs/display.texi
@@ -1452,9 +1452,10 @@ the displayed column number to count from one, you may set
@cindex narrowing, and line number display
If you have narrowed the buffer (@pxref{Narrowing}), the displayed
line number is relative to the accessible portion of the buffer.
-Thus, it isn't suitable as an argument to @code{goto-line}. (Use
-@code{what-line} command to see the line number relative to the whole
-file.)
+Thus, it isn't suitable as an argument to @code{goto-line}. (The
+command @code{what-line} shows the line number relative to the whole
+file.) You can use @code{goto-line-relative} command to move point to
+the line relative to the accessible portion of the narrowed buffer.
@vindex line-number-display-limit
If the buffer is very large (larger than the value of
diff --git a/etc/NEWS b/etc/NEWS
index a4c823072c9..fe2f5c37821 100644
--- a/etc/NEWS
+++ b/etc/NEWS
@@ -171,6 +171,13 @@ 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.
++++
+** New command 'goto-line-relative' to use in a narrowed buffer.
+It moves point to the line relative to the accessible portion of the
+narrowed buffer. 'M-g M-g' in Info is rebound to this command.
+When 'widen-automatically' is non-nil, 'goto-line' widens the narrowed
+buffer to be able to move point to the inaccessible portion.
+
+++
** When 'suggest-key-bindings' is non-nil, the completion list of 'M-x'
shows equivalent key bindings for all commands that have them.
diff --git a/lisp/info.el b/lisp/info.el
index e4f75b481fe..20633fd0598 100644
--- a/lisp/info.el
+++ b/lisp/info.el
@@ -4053,6 +4053,7 @@ If FORK is non-nil, it is passed to `Info-goto-node'."
(define-key map "^" 'Info-up)
(define-key map "," 'Info-index-next)
(define-key map "\177" 'Info-scroll-down)
+ (define-key map [remap goto-line] 'goto-line-relative)
(define-key map [mouse-2] 'Info-mouse-follow-nearest-node)
(define-key map [follow-link] 'mouse-face)
(define-key map [XF86Back] 'Info-history-back)
diff --git a/lisp/simple.el b/lisp/simple.el
index d7486e51ddc..825fec380cb 100644
--- a/lisp/simple.el
+++ b/lisp/simple.el
@@ -1231,7 +1231,39 @@ that uses or sets the mark."
"History of values entered with `goto-line'.")
(make-variable-buffer-local 'goto-line-history)
-(defun goto-line (line &optional buffer)
+(defun goto-line-read-args (&optional relative)
+ "Read arguments for `goto-line' related commands."
+ (if (and current-prefix-arg (not (consp current-prefix-arg)))
+ (list (prefix-numeric-value current-prefix-arg))
+ ;; Look for a default, a number in the buffer at point.
+ (let* ((default
+ (save-excursion
+ (skip-chars-backward "0-9")
+ (if (looking-at "[0-9]")
+ (string-to-number
+ (buffer-substring-no-properties
+ (point)
+ (progn (skip-chars-forward "0-9")
+ (point)))))))
+ ;; Decide if we're switching buffers.
+ (buffer
+ (if (consp current-prefix-arg)
+ (other-buffer (current-buffer) t)))
+ (buffer-prompt
+ (if buffer
+ (concat " in " (buffer-name buffer))
+ "")))
+ ;; Read the argument, offering that number (if any) as default.
+ (list (read-number (format "Goto%s line%s: "
+ (if (= (point-min) 1) ""
+ ;; In a narrowed buffer.
+ (if relative " relative" " absolute"))
+ buffer-prompt)
+ (list default (line-number-at-pos))
+ 'goto-line-history)
+ buffer))))
+
+(defun goto-line (line &optional buffer relative)
"Go to LINE, counting from line 1 at beginning of buffer.
If called interactively, a numeric prefix argument specifies
LINE; without a numeric prefix argument, read LINE from the
@@ -1241,6 +1273,13 @@ If optional argument BUFFER is non-nil, switch to that buffer and
move to line LINE there. If called interactively with \\[universal-argument]
as argument, BUFFER is the most recently selected other buffer.
+If optional argument RELATIVE is non-nil, counting starts at the beginning
+of the accessible portion of the (potentially narrowed) buffer.
+
+If the variable `widen-automatically' is non-nil, cancel narrowing and
+leave all lines accessible. If `widen-automatically' is nil, just move
+point to the edge of visible portion and don't change the buffer bounds.
+
Prior to moving point, this function sets the mark (without
activating it), unless Transient Mark mode is enabled and the
mark is already active.
@@ -1252,32 +1291,7 @@ What you probably want instead is something like:
If at all possible, an even better solution is to use char counts
rather than line counts."
(declare (interactive-only forward-line))
- (interactive
- (if (and current-prefix-arg (not (consp current-prefix-arg)))
- (list (prefix-numeric-value current-prefix-arg))
- ;; Look for a default, a number in the buffer at point.
- (let* ((default
- (save-excursion
- (skip-chars-backward "0-9")
- (if (looking-at "[0-9]")
- (string-to-number
- (buffer-substring-no-properties
- (point)
- (progn (skip-chars-forward "0-9")
- (point)))))))
- ;; Decide if we're switching buffers.
- (buffer
- (if (consp current-prefix-arg)
- (other-buffer (current-buffer) t)))
- (buffer-prompt
- (if buffer
- (concat " in " (buffer-name buffer))
- "")))
- ;; 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))
- 'goto-line-history)
- buffer))))
+ (interactive (goto-line-read-args))
;; Switch to the desired buffer, one way or another.
(if buffer
(let ((window (get-buffer-window buffer)))
@@ -1286,13 +1300,27 @@ rather than line counts."
;; Leave mark at previous position
(or (region-active-p) (push-mark))
;; Move to the specified line number in that buffer.
- (save-restriction
- (widen)
+ (if (and (not relative) (not widen-automatically))
+ (save-restriction
+ (widen)
+ (goto-char (point-min))
+ (if (eq selective-display t)
+ (re-search-forward "[\n\C-m]" nil 'end (1- line))
+ (forward-line (1- line))))
+ (unless relative (widen))
(goto-char (point-min))
(if (eq selective-display t)
(re-search-forward "[\n\C-m]" nil 'end (1- line))
(forward-line (1- line)))))
+(defun goto-line-relative (line &optional buffer)
+ "Go to LINE, counting from line at (point-min).
+The line number is relative to the accessible portion of the narrowed
+buffer. The argument BUFFER is the same as in the function `goto-line'."
+ (declare (interactive-only forward-line))
+ (interactive (goto-line-read-args t))
+ (goto-line line buffer t))
+
(defun count-words-region (start end &optional arg)
"Count the number of words in the region.
If called interactively, print a message reporting the number of
--
2.39.5