Bug 12273 – REGRESSION: File input value invisible after removing and re-appending

• Component: Forms
• Status: RESOLVED FIXED

[Jeremy Nicoll]

The current version of Safari does not reset the value of a file input object if it is reassigned to another form object like so:

  var f = document.getElementById('upload_file_ele');
  f.parentNode.removeChild(f);
  document.getElementById('form2').appendChild(f);

However, the latest nightly of WebKit resets the value so that the file input will read "No file selected."  This will cause issues for me in the future as I am developing an AJAX script that depends on the behavior of Safari as it currently stands because it monitors the upload of each file individually, and I have to assign each file input to a seperate form object in order to do so.  There is a similar behavior which is present in the latest versions of Safari and Webkit which are not present in Firefox or Opera, in which if the cloneNode(true) method is invoked on a file input element then the value is not cloned.  This was the first way I tried to solve my before-mentioned problem.

[David Kilzer (:ddkilzer)]

Jeremy, please attach a stand-alone test case of this issue to this bug.  Thanks!

[Jeremy Nicoll]

  Just to clarify, the desired behavior is that the value of the fine input element NOT be cleared when cloned or moved to another parent.

Scenario 1 (works in Safari, not in latest Webkit):

<script type="text/javascript">
	function press_this () {
		var f = document.getElementById('upload_1');
		f.parentNode.removeChild(f);
		document.getElementById('form2').appendChild(f);
	}
</script>

<form action="test.php" method="POST" enctype="multipart/form-data">
	<input type="file" name="upload" id="upload_1"/>
</form>

<input type="button" onclick="press_this();"/>
<form action="test.php" method="POST" id="form2" enctype="multipart/form-data">

</form>	
---------------------------------------
If you select a file, and then press the button, the selected file is gone in the element.


Scenario 2 (works in neither):

<script type="text/javascript">
	function press_this () {
		var f = document.getElementById('upload_1');
		var f2 = f.cloneNode(true);
		document.getElementById('form2').appendChild(f2);
	}
</script>

<form action="test.php" method="POST" enctype="multipart/form-data">
	<input type="file" name="upload" id="upload_1"/>
</form>

<input type="button" onclick="press_this();"/>
<form action="test.php" method="POST" id="form2" enctype="multipart/form-data">

</form>	
--------------------------------
   The selected value is not copied with cloneNode() in either Safari or the Webkit nightly.

[Alexey Proskuryakov]

Confirming the first case as a regression (->P1).

The second case is somewhat more questionable, since IE 7 also doesn't clone the file input value. It's likely that we will need to discuss it separately, may I ask you to file a new bug for it?

[David Kilzer (:ddkilzer)]

(In reply to comment #3)
> The second case is somewhat more questionable, since IE 7 also doesn't clone
> the file input value. It's likely that we will need to discuss it separately,
> may I ask you to file a new bug for it?

See Bug 12279.

[David Kilzer (:ddkilzer)]

(In reply to comment #4)
> (In reply to comment #3)
> > The second case is somewhat more questionable, since IE 7 also doesn't clone
> > the file input value. It's likely that we will need to discuss it separately,
> > may I ask you to file a new bug for it?
> See Bug 12279.

Bah!  See Bug 12285 instead.

[Darin Adler]

Created attachment 12474 [details]
scenario 1 as mentioned below

[Darin Adler]

Looking with the DOM inspector shows that the file input value is there after removing and appending. It's just not being displayed. I think if you upload the form you'll see the same thing. So retitling the bug for the actual symptom.

[Darin Adler]

Created attachment 12475 [details]
patch with change log

[Darin Adler]

*** Bug 12285 has been marked as a duplicate of this bug. ***

Comment on attachment 12475 [details]
patch with change log

Amusing:
- * Copyright (C) 2006 Apple Computer, Inc.
+ * Copyright (C) 2006, 2007 Apple Inc.
[...]
+ * 3.  Neither the name of Apple Computer, Inc. ("Apple") nor the names of

[Adam Roben (:aroben)]

Comment on attachment 12475 [details]
patch with change log

+        private instead, and made a coupld function members const.

Typo: "coupld"

r=me. Thanks for cleaning this up!

[David Kilzer (:ddkilzer)]

Added keyword to make this easier to find.

[Jeremy Nicoll]

Thank you for all your hard work!

[Sam Weinig]

Is a regression test possible for this patch?

[Darin Adler]

(In reply to comment #14)
> Is a regression test possible for this patch?

Not without adding something to WebCore and/or DumpRenderTree. For security reasons, you can't set an <input type=file> from JavaScript.

[Darin Adler]

Committed revision 19035.