Bug 177715 – clipboardData.setData() fails on iOS with certain kind of selections.

• Component: HTML Editing
• Status: RESOLVED CONFIGURATION CHANGED

[Lucas Garron]

As documented in https://bugs.webkit.org/show_bug.cgi?id=156529 , Safari doesn't allow document.execCommand("copy") when there is no selection.
It is possible work around this but by creating a temporary selection: https://bugs.webkit.org/show_bug.cgi?id=156529#c4

However, this workaround is broken on iOS. After the temporary selection is selected, document.queryCommandEnabled("copy") returns true and a function registered using document.addEventListener("copy", ...) fires. *However*, `event.clipboardData.setData()` has no effect.

Consider the following sample:

    <script>
    document.addEventListener("copy", function(e) {
      e.clipboardData.setData("text/plain", "This is plain text.");
      console.log(e.clipboardData.getData("text/plain"));
      e.preventDefault();
    });

    function copy() {
      var sel = document.getSelection();
      var range = document.createRange();
      range.selectNodeContents(document.body);
      sel.removeAllRanges();
      sel.addRange(range);
      document.execCommand("copy");
      window.getSelection().removeAllRanges();
    }
    </script>
    <button onclick='copy()'>Copy text (plain)</button>

The `console.log(...)` line prints "This is plain text." on desktop Safari, but a blank string on iOS.
Consequently, the clipboard is emptied (even if it contained something before).

[Wenson Hsieh]

(In reply to Lucas Garron from comment #0)
> As documented in https://bugs.webkit.org/show_bug.cgi?id=156529 , Safari
> doesn't allow document.execCommand("copy") when there is no selection.
> It is possible work around this but by creating a temporary selection:
> https://bugs.webkit.org/show_bug.cgi?id=156529#c4
> 
> However, this workaround is broken on iOS. After the temporary selection is
> selected, document.queryCommandEnabled("copy") returns true and a function
> registered using document.addEventListener("copy", ...) fires. *However*,
> `event.clipboardData.setData()` has no effect.
> 
> Consider the following sample:
> 
>     <script>
>     document.addEventListener("copy", function(e) {
>       e.clipboardData.setData("text/plain", "This is plain text.");
>       console.log(e.clipboardData.getData("text/plain"));
>       e.preventDefault();
>     });
> 
>     function copy() {
>       var sel = document.getSelection();
>       var range = document.createRange();
>       range.selectNodeContents(document.body);
>       sel.removeAllRanges();
>       sel.addRange(range);
>       document.execCommand("copy");
>       window.getSelection().removeAllRanges();
>     }
>     </script>
>     <button onclick='copy()'>Copy text (plain)</button>
> 
> The `console.log(...)` line prints "This is plain text." on desktop Safari,
> but a blank string on iOS.
> Consequently, the clipboard is emptied (even if it contained something
> before).

This is working for me using ToT WebKit, on iOS 11.

I'm pretty sure Ryosuke and I fixed this with recent work around enhanced pasteboard/DataTransfer support in WebKit.

[Wenson Hsieh]

> This is working for me using ToT WebKit, on iOS 11.
> 
> I'm pretty sure Ryosuke and I fixed this with recent work around enhanced
> pasteboard/DataTransfer support in WebKit.

...more specifically: <https://trac.webkit.org/changeset/222228/webkit>.

[Alexey Proskuryakov]

Marking resolved per the above comment.

[Radar WebKit Bug Importer]

<rdar://problem/34769566>

[Lucas Garron]

Thanks for the response!

Is there a way for me to test the latest behaviour on a (non-beta) iOS device?

Thanks,
»Lucas

[Ryosuke Niwa]

(In reply to Lucas Garron from comment #5)
> Thanks for the response!
> 
> Is there a way for me to test the latest behaviour on a (non-beta) iOS
> device?

You'd have to build WebKit's iOS port on iOS simulator. Follow instructions on https://github.com/WebKit/webkit