bug#26725: patch for mouse.el

bug#26725: patch for mouse.el

[Tak Kunihiro]

[-- Attachment #1: Type: Text/Plain, Size: 271 bytes --]

Drag and drop a file is already supported by Emacs.  This patch
extends drag and drop to region (text).

In other word, this patch lets you `cut and paste' in a buffer only
using mouse.  When destination is other windows, drag and drop a
region will be `copy and paste'.

[-- Attachment #2: mouse.el.patch --]
[-- Type: Text/X-Patch, Size: 4807 bytes --]

--- mouse.252.el	2017-05-01 13:45:39.735936700 +0900
+++ mouse.el	2017-05-01 13:59:11.102725500 +0900
@@ -688,12 +688,19 @@
 Highlight the drag area as you move the mouse.
 This must be bound to a button-down mouse event.
 In Transient Mark mode, the highlighting remains as long as the mark
-remains active.  Otherwise, it remains until the next input event."
-  (interactive "e")
-  ;; Give temporary modes such as isearch a chance to turn off.
-  (run-hooks 'mouse-leave-buffer-hook)
-  (mouse-drag-track start-event))
+remains active.  Otherwise, it remains until the next input event.
 
+When the region already exists and `mouse-drag-and-drop-region'
+is non-nil, this moves text on a region to point where mouse is
+dragged over to."
+  (interactive "e")
+  (if (and mouse-drag-and-drop-region
+           (not (member 'triple (event-modifiers start-event)))
+           (mouse-on-region-p (event-start start-event)))
+      (mouse-drag-region-pasting start-event)
+    ;; Give temporary modes such as isearch a chance to turn off.
+    (run-hooks 'mouse-leave-buffer-hook)
+    (mouse-drag-track start-event)))
 
 (defun mouse-posn-property (pos property)
   "Look for a property at click position.
@@ -1911,6 +1918,94 @@
 		  t (called-interactively-p 'interactive)))))))))
 
 \f
+;; Drag and drop support.
+(defcustom mouse-drag-and-drop-region nil
+  "If non-nil, dragging mouse of the region moves text."
+  :type 'boolean
+  :version "26.1"
+  :group 'mouse)
+
+(defun mouse-on-region-p (position &optional start end)
+  "Return if POSITION is in between START and END in the current buffer.
+When START and END are nil but there is active region, those of
+active region is fed."
+  (when (region-active-p)
+    (setq start (or start (region-beginning)))
+    (setq end (or end (region-end))))
+  (let ((point (posn-point position)))
+    (and
+     (numberp start)
+     (numberp end)
+     (numberp point)
+     (<= start point)
+     (<= point end))))
+
+(defun mouse-drag-region-pasting (event)
+  "Move text on a region to point where mouse is dragged over to.
+The transportation of text is also referred as `drag and drop'.
+When text is dragged over to different buffer, the text is copied
+instead of cut.  This works similar to
+`mouse-drag-secondary-moving' but expects region on launch and
+specifies point later, by mouse.
+
+To try this function, evaluate the following line.
+	(global-set-key [down-mouse-3] \\='mouse-drag-region-pasting)
+Then have a region and grab-and-drag it by mouse to point to move
+to."
+  (interactive "e")
+  (require 'tooltip)
+  (let ((start (region-beginning))
+        (end (region-end))
+        (point (point))
+        (buffer (current-buffer))
+        (window (selected-window))
+        value-selection)
+    (track-mouse
+      ;; when event was click instead of drag, skip loop
+      (while (progn
+               (setq event (read-event))
+               (mouse-movement-p event))
+        (unless value-selection ; initialization
+          (delete-overlay mouse-secondary-overlay)
+          (setq value-selection (buffer-substring start end))
+          (move-overlay mouse-secondary-overlay start end)) ; (deactivate-mark)
+        (ignore-errors (deactivate-mark) ; care existing region in other window
+                       (mouse-set-point event)
+                       (tooltip-show value-selection)))
+      (tooltip-hide))
+    ;; Do not modify buffer when "event was click",
+    ;; "drag negligible", or "drag to read-only".
+    (if (or (mouse-on-region-p (event-end event) start end)
+            buffer-read-only)
+        (cond
+         ;; drag negligible or drag to read-only, restore region
+         (value-selection
+          (select-window window) ; case miss drag to other window
+          (goto-char point)
+          (setq deactivate-mark nil)
+          (activate-mark))
+         ;; event was click
+         (t
+          (deactivate-mark)
+          (mouse-set-point event)))
+      ;; insert text
+      (push-mark)
+      (insert value-selection) ; revise buffer
+      (when (not (equal (mark) (point))) ; on success
+        (setq deactivate-mark nil)
+        (activate-mark)) ; activate region on new place
+      ;; take out initial region
+      (if (equal (current-buffer) buffer) ; same buffer
+          (let (deactivate-mark)
+            (kill-region (overlay-start mouse-secondary-overlay)
+                         (overlay-end mouse-secondary-overlay)))
+        (let ((window1 (selected-window))) ; beyond buffer
+          (select-window window)
+          (goto-char point) ; restore point to where it was
+          (select-window window1))))
+    (delete-overlay mouse-secondary-overlay)))
+\f
+
 ;;; Bindings for mouse commands.
 
 (global-set-key [down-mouse-1]	'mouse-drag-region)

bug#26725: patch for mouse.el

[Tak Kunihiro]

Is this patch NG?

I think `drag-and-drop text' using mouse gives modern flavor to Emacs,
and idea should be good.

Would you tell me how this patch is NG, if so?

bug#26725: patch for mouse.el

[Eli Zaretskii]

> Date: Sun, 07 May 2017 07:06:21 +0900 (JST)
> From: Tak Kunihiro <tkk@misasa.okayama-u.ac.jp>
> Cc: tkk@misasa.okayama-u.ac.jp
> 
> Is this patch NG?
> 
> I think `drag-and-drop text' using mouse gives modern flavor to Emacs,
> and idea should be good.
> 
> Would you tell me how this patch is NG, if so?

Sorry, I didn't yet have time to look into your patch (and hoped
someone else might, meanwhile...)

bug#26725: patch for mouse.el

[Tak Kunihiro]

>> Is this patch NG?
>> 
>> I think `drag-and-drop text' using mouse gives modern flavor to Emacs,
>> and idea should be good.
>> 
>> Would you tell me how this patch is NG, if so?
> 
> Sorry, I didn't yet have time to look into your patch (and hoped
> someone else might, meanwhile...)

I see.  No problem.  Please take you time, and eventually give me
response.

bug#26725: patch for mouse.el

[Eli Zaretskii]

> Date: Mon, 01 May 2017 14:43:08 +0900 (JST)
> From: Tak Kunihiro <tkk@misasa.okayama-u.ac.jp>
> Cc: tkk@misasa.okayama-u.ac.jp
> 
> Drag and drop a file is already supported by Emacs.  This patch
> extends drag and drop to region (text).

Thanks.  Some comments below.

> +When the region already exists and `mouse-drag-and-drop-region'
> +is non-nil, this moves text on a region to point where mouse is
               ^^^^^^^^^^^^^^^^^^^^^^^^^^^
"this moves the entire region of text"

> +(defcustom mouse-drag-and-drop-region nil
> +  "If non-nil, dragging mouse of the region moves text."

"If non-nil, dragging the mouse drags the region, when that exists.

> +(defun mouse-on-region-p (position &optional start end)
> +  "Return if POSITION is in between START and END in the current buffer.
> +When START and END are nil but there is active region, those of
> +active region is fed."
> +  (when (region-active-p)
> +    (setq start (or start (region-beginning)))
> +    (setq end (or end (region-end))))
> +  (let ((point (posn-point position)))
> +    (and
> +     (numberp start)
> +     (numberp end)
> +     (numberp point)
> +     (<= start point)
> +     (<= point end))))

This algorithm will fail with bidirectional text, where buffer
positions don't increase monotonically with screen coordinates.  How
about testing the face of the character under mouse instead?

> +(defun mouse-drag-region-pasting (event)

The function's name is confusing.  Why not name it like the defcustom?

> +  "Move text on a region to point where mouse is dragged over to.
                ^^
"in"

> +The transportation of text is also referred as `drag and drop'.
> +When text is dragged over to different buffer, the text is copied
                               ^
"a" is missing here.

> +instead of cut.

"instead of being cur".

>                      This works similar to
> +`mouse-drag-secondary-moving' but expects region on launch and
> +specifies point later, by mouse.

I'd lose this sentence, it doesn't add anything to the doc string.

> +To try this function, evaluate the following line.
> +	(global-set-key [down-mouse-3] \\='mouse-drag-region-pasting)
> +Then have a region and grab-and-drag it by mouse to point to move
> +to."

I think this is inappropriate for a doc string.

Please add a NEWS entry and some minimal documentation in the user
manual.

bug#26725: patch for mouse.el

[Tak Kunihiro]

[-- Attachment #1: Type: Text/Plain, Size: 3425 bytes --]

Thank you for the comments.  I revised English as suggested.

>> +(defun mouse-on-region-p (position &optional start end)
>> +  "Return if POSITION is in between START and END in the current buffer.
>> +When START and END are nil but there is active region, those of
>> +active region is fed."
>> +  (when (region-active-p)
>> +    (setq start (or start (region-beginning)))
>> +    (setq end (or end (region-end))))
>> +  (let ((point (posn-point position)))
>> +    (and
>> +     (numberp start)
>> +     (numberp end)
>> +     (numberp point)
>> +     (<= start point)
>> +     (<= point end))))
>
> This algorithm will fail with bidirectional text, where buffer
> positions don't increase monotonically with screen coordinates.  How
> about testing the face of the character under mouse instead?

I revised the code using following statements.  Accordingly,
`mouse-on-region-p' is not necessary anymore.

(equal (mouse-posn-property (event-start start-event) 'face) 'region)
(equal (mouse-posn-property (event-start start-event) 'face) 'secondary-selecton)

>> +(defun mouse-drag-region-pasting (event)
>
> The function's name is confusing.  Why not name it like the defcustom?

I changed the name from `mouse-drag-region-pasting' to
`mouse-drag-and-drop-region'.

> Please add a NEWS entry and some minimal documentation in the user
> manual.

I add ChangeLog, NEWS, and Info as shown below.  I think that all
concerns were resolved for now.


# ChangeLog

2017-05-16  Tak Kunihiro  <tkk@misasa.okayama-u.ac.jp>

	Support drag and drop region by the mouse (Bug#26725)

	* doc/emacs/frames.texi (Drag and Drop): Document support of drag
    and drop region by the mouse.
	* lisp/mouse.el (mouse-drag-region): Call mouse-drag-and-drop-region
    when start-event is against region.
    (mouse-drag-and-drop-region): Move the region by dragging the mouse.

# NEWS

** Support drag and drop text by the mouse.
You can start drag-and-drop text by customizing 'mouse-drag-and-drop-region'.

# Info

diff --git a/site-lisp/frames.252.texi b/site-lisp/frames.texi
index 1611bd1..da140a6 100755
--- a/site-lisp/frames.252.texi
+++ b/site-lisp/frames.texi
@@ -1046,12 +1046,17 @@ Window Dividers, elisp, The Emacs Lisp Reference Manual}.
 @cindex drag and drop

   In most graphical desktop environments, Emacs has basic support for
-@dfn{drag and drop} operations.  For instance, dropping text onto an
-Emacs frame inserts the text where it is dropped.  Dropping a file
-onto an Emacs frame visits that file.  As a special case, dropping the
-file on a Dired buffer moves or copies the file (according to the
-conventions of the application it came from) into the directory
-displayed in that buffer.
+@dfn{drag and drop} operations.  For instance, dragging region can move
+the entire region of text to point where mouse is dragged over to.
+Dropping text onto an Emacs frame inserts the text where it is dropped.
+Dropping a file onto an Emacs frame visits that file.  As a special
+case, dropping the file on a Dired buffer moves or copies the file
+(according to the conventions of the application it came from) into the
+directory displayed in that buffer.
+
+@vindex mouse-drag-and-drop-region
+  If you prefer to move the entire region of text by mouse, customize
+the variable @code{mouse-drag-and-drop-region}.

 @vindex dnd-open-file-other-window
   Dropping a file normally visits it in the window you drop it on.  If

[-- Attachment #2: mouse.el.patch --]
[-- Type: Text/X-Patch, Size: 4355 bytes --]

diff --git a/mouse.252.el b/mouse.el
index 3336e2b..b8cc92c 100755
--- a/mouse.252.el
+++ b/mouse.el
@@ -688,12 +688,19 @@ Upon exit, point is at the far edge of the newly visible text."
 Highlight the drag area as you move the mouse.
 This must be bound to a button-down mouse event.
 In Transient Mark mode, the highlighting remains as long as the mark
-remains active.  Otherwise, it remains until the next input event."
-  (interactive "e")
-  ;; Give temporary modes such as isearch a chance to turn off.
-  (run-hooks 'mouse-leave-buffer-hook)
-  (mouse-drag-track start-event))
+remains active.  Otherwise, it remains until the next input event.
 
+When the region already exists and `mouse-drag-and-drop-region'
+is non-nil, this moves the entire region of text to point where
+mouse is dragged over to."
+  (interactive "e")
+  (if (and mouse-drag-and-drop-region
+           (not (member 'triple (event-modifiers start-event)))
+           (equal (mouse-posn-property (event-start start-event) 'face) 'region))
+      (mouse-drag-and-drop-region start-event)
+    ;; Give temporary modes such as isearch a chance to turn off.
+    (run-hooks 'mouse-leave-buffer-hook)
+    (mouse-drag-track start-event)))
 
 (defun mouse-posn-property (pos property)
   "Look for a property at click position.
@@ -1911,6 +1918,76 @@ choose a font."
 		  t (called-interactively-p 'interactive)))))))))
 
 \f
+;; Drag and drop support.
+(defcustom mouse-drag-and-drop-region nil
+  "If non-nil, dragging the mouse drags the region, when that exists."
+  :type 'boolean
+  :version "26.1"
+  :group 'mouse)
+
+(defun mouse-drag-and-drop-region (event)
+  "Move text in a region to point where mouse is dragged over to.
+The transportation of text is also referred as `drag and drop'.
+When text is dragged over to a different buffer, the text is
+copied instead of being cut."
+  (interactive "e")
+  (require 'tooltip)
+  (let ((start (region-beginning))
+        (end (region-end))
+        (point (point))
+        (buffer (current-buffer))
+        (window (selected-window))
+        value-selection
+        face-under-mouse)
+    (track-mouse
+      ;; When event was click instead of drag, skip loop
+      (while (progn
+               (setq event (read-event))
+               (mouse-movement-p event))
+        (unless value-selection ; initialization
+          (delete-overlay mouse-secondary-overlay)
+          (setq value-selection (buffer-substring start end))
+          (move-overlay mouse-secondary-overlay start end)) ; (deactivate-mark)
+        (ignore-errors (deactivate-mark) ; care existing region in other window
+                       (mouse-set-point event)
+                       (tooltip-show value-selection)))
+      (tooltip-hide))
+    ;; Do not modify buffer when "event was click",
+    ;; "drag negligible", or "drag to read-only".
+    (setq face-under-mouse (mouse-posn-property (event-end event) 'face))
+    (if (or (equal face-under-mouse 'region)
+            (equal face-under-mouse 'secondary-selecton)
+            buffer-read-only)
+        ;; Do not modify buffer under mouse
+        (cond
+         ;; drag negligible or drag to read-only, restore region
+         (value-selection
+          (select-window window) ; case miss drag to other window
+          (goto-char point)
+          (setq deactivate-mark nil)
+          (activate-mark))
+         ;; event was click
+         (t
+          (deactivate-mark)
+          (mouse-set-point event)))
+      ;; Modify buffer under mouse by inserting text
+      (push-mark)
+      (insert value-selection)
+      (when (not (equal (mark) (point))) ; on success
+        (setq deactivate-mark nil)
+        (activate-mark)) ; activate region on new place
+      ;; Take care initial region
+      (if (equal (current-buffer) buffer) ; same buffer
+          (let (deactivate-mark) ; remove text
+            (kill-region (overlay-start mouse-secondary-overlay)
+                         (overlay-end mouse-secondary-overlay)))
+        (let ((window1 (selected-window))) ; beyond buffer
+          (select-window window)
+          (goto-char point) ; restore point to where it was
+          (select-window window1))))
+    (delete-overlay mouse-secondary-overlay)))
+\f
+
 ;;; Bindings for mouse commands.
 
 (global-set-key [down-mouse-1]	'mouse-drag-region)

bug#26725: patch for mouse.el

[Tak Kunihiro]

Let me withdraw the last patch.
I found a problem with following statement.

(equal (mouse-posn-property (event-end event) 'face) 'secondary-selecton)

bug#26725: patch for mouse.el

[Tak Kunihiro]

[-- Attachment #1: Type: Text/Plain, Size: 4043 bytes --]

Thank you for the comments.

* English

I revised English as suggested.


* Algorithm in detection of clicking region

>> +(defun mouse-on-region-p (position &optional start end)
>> +  "Return if POSITION is in between START and END in the current buffer.
>> +When START and END are nil but there is active region, those of
>> +active region is fed."
>> +  (when (region-active-p)
>> +    (setq start (or start (region-beginning)))
>> +    (setq end (or end (region-end))))
>> +  (let ((point (posn-point position)))
>> +    (and
>> +     (numberp start)
>> +     (numberp end)
>> +     (numberp point)
>> +     (<= start point)
>> +     (<= point end))))
>
> This algorithm will fail with bidirectional text, where buffer
> positions don't increase monotonically with screen coordinates.  How
> about testing the face of the character under mouse instead?

I revised the code using following statements.  Accordingly,
`mouse-on-region-p' is deleted.

(equal (mouse-posn-property (event-end event) 'face) 'region)
(member 'secondary-selection(mapcar (lambda (xxx) (overlay-get xxx 'face))
                            (overlays-at (posn-point (event-end event)))))


* Name of function

>> +(defun mouse-drag-region-pasting (event)
>
> The function's name is confusing.  Why not name it like the defcustom?

I changed the name from `mouse-drag-region-pasting' to
`mouse-drag-and-drop-region'.  As a consequence, variable and function
have the same name.  I suppose it is OK.


* NEWS, ChangeLog, and Info

> Please add a NEWS entry and some minimal documentation in the user
> manual.

I add ChangeLog, NEWS, and Info as shown below.


* Copy on Drag and Drop with meta key pressed

I found that sometimes I want to copy on drop (instead of cut) even
when source buffer and destination buffer are the same.

I added a logic to let me do so.  When modifier key is pressed on
drop, the function does not delete the original region.

The modifier key is specified by the variable
`mouse-drag-and-drop-region' that is used as flag.  I did not create a
new variable.




# ChangeLog

2017-05-20  Tak Kunihiro  <tkk@misasa.okayama-u.ac.jp>

	Support drag and drop region by the mouse (Bug#26725)

	* doc/emacs/frames.texi (Drag and Drop): Document support of drag
    and drop region by the mouse.
	* lisp/mouse.el (mouse-drag-region): Call mouse-drag-and-drop-region
    when start-event is against region.
    (mouse-drag-and-drop-region): Move the region by dragging the mouse.

# NEWS

** Support drag and drop text by the mouse.
You can start drag-and-drop text by customizing 'mouse-drag-and-drop-region'.

# Info

diff --git a/site-lisp/frames.252.texi b/site-lisp/frames.texi
index 1611bd1..da140a6 100755
--- a/site-lisp/frames.252.texi
+++ b/site-lisp/frames.texi
@@ -1046,12 +1046,17 @@ Window Dividers, elisp, The Emacs Lisp Reference Manual}.
 @cindex drag and drop

   In most graphical desktop environments, Emacs has basic support for
-@dfn{drag and drop} operations.  For instance, dropping text onto an
-Emacs frame inserts the text where it is dropped.  Dropping a file
-onto an Emacs frame visits that file.  As a special case, dropping the
-file on a Dired buffer moves or copies the file (according to the
-conventions of the application it came from) into the directory
-displayed in that buffer.
+@dfn{drag and drop} operations.  For instance, dragging region can move
+the entire region of text to point where mouse is dragged over to.
+Dropping text onto an Emacs frame inserts the text where it is dropped.
+Dropping a file onto an Emacs frame visits that file.  As a special
+case, dropping the file on a Dired buffer moves or copies the file
+(according to the conventions of the application it came from) into the
+directory displayed in that buffer.
+
+@vindex mouse-drag-and-drop-region
+  If you prefer to move the entire region of text by mouse, customize
+the variable @code{mouse-drag-and-drop-region}.

 @vindex dnd-open-file-other-window
   Dropping a file normally visits it in the window you drop it on.  If



[-- Attachment #2: mouse.el.patch --]
[-- Type: Text/X-Patch, Size: 4831 bytes --]

diff --git a/mouse.252.el b/mouse.el
index 3336e2b..66142f4 100755
--- a/mouse.252.el
+++ b/mouse.el
@@ -688,12 +688,19 @@ Upon exit, point is at the far edge of the newly visible text."
 Highlight the drag area as you move the mouse.
 This must be bound to a button-down mouse event.
 In Transient Mark mode, the highlighting remains as long as the mark
-remains active.  Otherwise, it remains until the next input event."
-  (interactive "e")
-  ;; Give temporary modes such as isearch a chance to turn off.
-  (run-hooks 'mouse-leave-buffer-hook)
-  (mouse-drag-track start-event))
+remains active.  Otherwise, it remains until the next input event.
 
+When the region already exists and the variable
+`mouse-drag-and-drop-region' is non-nil, this moves the entire
+region of text to point where mouse is dragged over to."
+  (interactive "e")
+  (if (and mouse-drag-and-drop-region
+           (not (member 'triple (event-modifiers start-event)))
+           (equal (mouse-posn-property (event-start start-event) 'face) 'region))
+      (mouse-drag-and-drop-region start-event)
+    ;; Give temporary modes such as isearch a chance to turn off.
+    (run-hooks 'mouse-leave-buffer-hook)
+    (mouse-drag-track start-event)))
 
 (defun mouse-posn-property (pos property)
   "Look for a property at click position.
@@ -1911,6 +1918,81 @@ choose a font."
 		  t (called-interactively-p 'interactive)))))))))
 
 \f
+;; Drag and drop support.
+(defcustom mouse-drag-and-drop-region nil
+  "If non-nil, dragging the mouse drags the region, when that exists.
+When the modifier key is specified, dropping with the modifier
+key pressed copies the text instead of cuts."
+  :type 'symbol
+  :version "26.1"
+  :group 'mouse)
+
+(defun mouse-drag-and-drop-region (event)
+  "Move text in a region to point where mouse is dragged over to.
+The transportation of text is also referred as `drag and drop'.
+When text is dragged over to a different buffer, the text is
+copied instead of being cut."
+  (interactive "e")
+  (require 'tooltip)
+  (let ((start (region-beginning))
+        (end (region-end))
+        (point (point))
+        (buffer (current-buffer))
+        (window (selected-window))
+        value-selection)
+    (track-mouse
+      ;; When event was click instead of drag, skip loop
+      (while (progn
+               (setq event (read-event))
+               (mouse-movement-p event))
+        (unless value-selection ; initialization
+          (delete-overlay mouse-secondary-overlay)
+          (setq value-selection (buffer-substring start end))
+          (move-overlay mouse-secondary-overlay start end)) ; (deactivate-mark)
+        (ignore-errors (deactivate-mark) ; care existing region in other window
+                       (mouse-set-point event)
+                       (tooltip-show value-selection)))
+      (tooltip-hide))
+    ;; Do not modify buffer under mouse when "event was click",
+    ;;                                       "drag negligible", or
+    ;;                                       "drag to read-only".
+    (if (or (equal (mouse-posn-property (event-end event) 'face) 'region) ; "event was click"
+            (member 'secondary-selection ; "drag negligible"
+                    (mapcar (lambda (xxx) (overlay-get xxx 'face))
+                            (overlays-at (posn-point (event-end event)))))
+            buffer-read-only)
+        ;; Do not modify buffer under mouse
+        (cond
+         ;; "drag negligible" or "drag to read-only", restore region
+         (value-selection
+          (select-window window) ; case miss drag to other window
+          (goto-char point)
+          (setq deactivate-mark nil)
+          (activate-mark))
+         ;; "event was click"
+         (t
+          (deactivate-mark)
+          (mouse-set-point event)))
+      ;; Modify buffer under mouse by inserting text
+      (push-mark)
+      (insert value-selection)
+      (when (not (equal (mark) (point))) ; on success insert
+        (setq deactivate-mark nil)
+        (activate-mark)) ; have region on destination
+      ;; Take care initial region on source
+      (if (equal (current-buffer) buffer) ; when same buffer
+          (let (deactivate-mark) ; remove text
+            (unless (member mouse-drag-and-drop-region (event-modifiers event))
+              (kill-region (overlay-start mouse-secondary-overlay)
+                           (overlay-end mouse-secondary-overlay))))
+        (let ((window1 (selected-window))) ; when beyond buffer
+          (select-window window)
+          (goto-char point) ; restore point on source window
+          (activate-mark) ; restore region
+          (select-window window1))))
+    (delete-overlay mouse-secondary-overlay)))
+\f
+
 ;;; Bindings for mouse commands.
 
 (global-set-key [down-mouse-1]	'mouse-drag-region)

bug#26725: patch for mouse.el

[Eli Zaretskii]

> Date: Fri, 19 May 2017 11:07:43 +0900 (JST)
> Cc: 26725@debbugs.gnu.org, tkk@misasa.okayama-u.ac.jp,
>  tkk@misasa.okayama-u.ac.jp
> From: Tak Kunihiro <tkk@misasa.okayama-u.ac.jp>
> 
> Thank you for the comments.
> 
> * English
> 
> I revised English as suggested.
> 
> 
> * Algorithm in detection of clicking region
> 
> >> +(defun mouse-on-region-p (position &optional start end)
> >> +  "Return if POSITION is in between START and END in the current buffer.
> >> +When START and END are nil but there is active region, those of
> >> +active region is fed."
> >> +  (when (region-active-p)
> >> +    (setq start (or start (region-beginning)))
> >> +    (setq end (or end (region-end))))
> >> +  (let ((point (posn-point position)))
> >> +    (and
> >> +     (numberp start)
> >> +     (numberp end)
> >> +     (numberp point)
> >> +     (<= start point)
> >> +     (<= point end))))
> >
> > This algorithm will fail with bidirectional text, where buffer
> > positions don't increase monotonically with screen coordinates.  How
> > about testing the face of the character under mouse instead?
> 
> I revised the code using following statements.  Accordingly,
> `mouse-on-region-p' is deleted.
> 
> (equal (mouse-posn-property (event-end event) 'face) 'region)
> (member 'secondary-selection(mapcar (lambda (xxx) (overlay-get xxx 'face))
>                             (overlays-at (posn-point (event-end event)))))
> 
> 
> * Name of function
> 
> >> +(defun mouse-drag-region-pasting (event)
> >
> > The function's name is confusing.  Why not name it like the defcustom?
> 
> I changed the name from `mouse-drag-region-pasting' to
> `mouse-drag-and-drop-region'.  As a consequence, variable and function
> have the same name.  I suppose it is OK.
> 
> 
> * NEWS, ChangeLog, and Info
> 
> > Please add a NEWS entry and some minimal documentation in the user
> > manual.
> 
> I add ChangeLog, NEWS, and Info as shown below.
> 
> 
> * Copy on Drag and Drop with meta key pressed
> 
> I found that sometimes I want to copy on drop (instead of cut) even
> when source buffer and destination buffer are the same.
> 
> I added a logic to let me do so.  When modifier key is pressed on
> drop, the function does not delete the original region.
> 
> The modifier key is specified by the variable
> `mouse-drag-and-drop-region' that is used as flag.  I did not create a
> new variable.

Thanks, pushed to master.