[PATCH v3 6/6] line-range-highlight: copy URL to clipboard on click

[john at keeping.me.uk (John Keeping)]

On Sun, Jun 24, 2018 at 11:06:45PM +0800, Andy Green wrote:
> On June 24, 2018 9:39:35 PM GMT+08:00, John Keeping <john at keeping.me.uk> wrote:
> >On Sun, Jun 24, 2018 at 08:00:08PM +0800, Andy Green wrote:
> >> On June 24, 2018 7:42:33 PM GMT+08:00, John Keeping
> ><john at keeping.me.uk> wrote:
> >> >On Sun, Jun 24, 2018 at 10:44:54AM +0800, Andy Green wrote:
> >> >> Since the only reason to click on the line number links
> >> >> is to get the corresponding #URL to share, this patch
> >> >> makes that process more convenient by copying the
> >> >> highlit area, be it a single line or a range, to the
> >> >> clipboard on each click of the line number links.
> >> >
> >> >As a user, I'd find this surprising and probably quite annoying.
> >> >
> >> >I strongly prefer that software not overwrite the clipboard contents
> >> >without an explicit request to do so.  A quick survey suggests none
> >of
> >> >GitHub, Gitlab or repo.or.cz (GitWeb) behave in this way.
> >> 
> >> Is there another possible intention behind clicking on the line
> >number
> >> links I am missing?
> >
> >One I can think of (given your recent patches) is to highlight a line
> >when pointing it out to someone else looking at the same display.  I
> >have definitely used this with other web interfaces in the past.
> 
> Well, ok, so he can click on it to show his buddy.  He gets the URL in
> his clipboard.  But his buddy is there he doesn't need it.

And what about the piece of code that was cut into the clipboard just
before the interruption?

> >> If not, literally the only reason to click on them is because you
> >> intend to copy the #URL to the clipboard.
> >> 
> >> Then that is "an explicit request", isn't it?
> >
> >In the X11 world there are separate selection buffers for selecting
> >text
> >and for Ctrl-C/V behaviour [1].  It might not be unreasonable to set
> >PRIMARY to the URL, but setting CLIPBOARD is clearly wrong.
> >
> >My use of "explicit" above is consistent with the use in this spec,
> >unless the user has selected Copy, or pressed Ctrl-C there is no
> >expectation that the clipboard will be overwritten.
> >
> >Certainly for an X11 user overwriting CLIPBOARD when clicking a
> 
> The browser has no idea about that.  Cgit isn't an X11 beast, it feeds
> crossplatform browsers.
> 
> If the browser copies anything to the clipboard by js api, it's always
> the ^C ^V one since the js stuff only has the concept of that one.  So
> in the case the user wants this behaviour, the surprising thing would
> be on some platforms it went in some other "clipboard" (this is not
> possible in js afaik).  The user would be nonplussed if it could and
> then he was sat in front of a windows browser.  So I think the
> observations about that lead nowhere.
> 
> >hyperlink fails the principle of least surprise, and I think that
> 
> Well, I used it and I liked it.  It felt pretty natural.  But an extra
> click won't kill me.
> 
> >applies to all users because this isn't how web pages work: on any
> >other
> >page, if I want to copy a link I right-click and copy the link.  I
> >don't
> >expect the clipboard to be overwritten just because I clicked a
> >hyperlink.
> 
> On github it pops up a sticky popup with an ellipsis because you
> "clicked a hyperlink" in the same conditions.  (Clicking that brings a
> js menu with a copy entry).  Users can handle variation, at least if
> it's indicating to them what's happening and why, and is useful.  At
> least it doesn't seem to have held github back...

That's fine, it doesn't overwrite the clipboard with no notice (and
right-click still works).  My point isn't "we can't provide a new way to
copy to the clipboard", it's "we can't overwrite the clipboard behind
the user's back".

> The link we want to copy is not the ...#nXXX link in the a href when
> there is a range up.  I never tried to intercept "Copy Link", maybe it
> could be done.  But at least the default menu won't do as it is in
> this case.
> 
> I think no point for the two-step menu like github since the only
> option we plan to show atm is Copy (the other useful option is switch
> to blame at that line).  How about a popup that appears on the left
> for a few secs with a copy type icon, or "Copy", in it, that fades
> away if not used?  It's one extra click but still one less than
> github.

This sounds good.  Copying the line range link is clearly useful and
this way the user knows that it's an option and controls when it
happens.

> >[1]
> >https://specifications.freedesktop.org/clipboards-spec/clipboards-0.1.txt
> >
> >> >> Signed-off-by: Andy Green <andy at warmcat.com>
> >> >> ---
> >> >>  cgit.js |   36 ++++++++++++++++++++++++++++++++----
> >> >>  1 file changed, 32 insertions(+), 4 deletions(-)
> >> >> 
> >> >> diff --git a/cgit.js b/cgit.js
> >> >> index 2cfad29..e2c3799 100644
> >> >> --- a/cgit.js
> >> >> +++ b/cgit.js
> >> >> @@ -89,8 +89,29 @@ function cgit_line_range_highlight()
> >> >>  		e.scrollIntoView(true);
> >> >>  }
> >> >>  
> >> >> +function cgit_copy_clipboard(value)
> >> >> +{
> >> >> +	var inp = document.createElement("textarea");
> >> >> +	var e = document.getElementById("linenumber_td");
> >> >> +
> >> >> +	inp.type = "text";
> >> >> +	inp.value = value;
> >> >> +	/* hidden style stops it working for clipboard */
> >> >> +	inp.setAttribute('readonly', '');
> >> >> +	inp.style.position = "absolute";
> >> >> +	inp.style.left = "-1000px";
> >> >> +
> >> >> +	e.appendChild(inp);
> >> >> +
> >> >> +	inp.select();
> >> >> +
> >> >> +	document.execCommand("copy");
> >> >> +
> >> >> +	inp.remove();
> >> >> +}
> >> >> +
> >> >>  function cgit_line_range_click(e) {
> >> >> -	var t = e.target.id;
> >> >> +	var t = e.target.id, cp;
> >> >>  
> >> >>  	cgit_line_range_override = null;
> >> >>  
> >> >> @@ -101,13 +122,13 @@ function cgit_line_range_click(e) {
> >> >>  	 * is called, and override it there.
> >> >>  	 */
> >> >>  
> >> >> -	if (window.location.hash && window.location.hash.indexOf("-") <
> >0)
> >> >> +	if (window.location.hash && window.location.hash.indexOf("-") <
> >0)
> >> >{
> >> >>  		if (parseInt(window.location.hash.substring(2)) <
> >> >>  		    parseInt(t.substring(1))) /* forwards */
> >> >> -			cgit_line_range_override =
> >> >> +			cp = cgit_line_range_override =
> >> >>  				window.location + '-' + t.substring(1);
> >> >>  		else /* backwards */
> >> >> -			cgit_line_range_override =
> >> >> +			cp = cgit_line_range_override =
> >> >>  				window.location.href.substring(0,
> >> >>  					window.location.href.length -
> >> >>  					window.location.hash.length) +
> >> >> @@ -115,6 +136,13 @@ function cgit_line_range_click(e) {
> >> >>  					window.location.href.substring(
> >> >>  						window.location.href.length -
> >> >>  						window.location.hash.length + 2);
> >> >> +	} else
> >> >> +		cp = window.location.href.substring(0,
> >> >> +                                       
> >window.location.href.length
> >> >-
> >> >> +                                       
> >window.location.hash.length)
> >> >+
> >> >> +			'#n' + t.substring(1);
> >> >> +
> >> >> +	cgit_copy_clipboard(cp);
> >> >>  }
> >> >>  
> >> >>  /* line range highlight */
> >> >> 
> >> >> _______________________________________________
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> >> >> https://lists.zx2c4.com/mailman/listinfo/cgit
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