1708670 - nsIEditor.pasteTransferable won't insert image/png if nsITransaferable uses nsIInputStream

Status: RESOLVED FIXED

(Core :: DOM: Editor, defect, P2)

Description

[Makoto Kato [:m_kato]]

I found this when I tried to use pasteTransferable for image keyboard support (https://developer.android.com/guide/topics/text/image-keyboard).

pasteTransferable initializes DataTransfer when using nsITransferable parameter.

https://searchfox.org/mozilla-central/rev/1ed1bb14eed9b3f27a94513387608436ea74c247/editor/libeditor/HTMLEditorDataTransfer.cpp#2083

But when mime type is image/png, this is recognized as KIND_FILE at here. So if using nsIInputStream, this fetches all data at
here. Then, when InsertObject tries fetching data from nsIInputStream, this stream of image/png is already EOF. So at finally, we cannot insert PNG image.

Comment 1

[Makoto Kato [:m_kato]]

Attachment: Bug 1708670 - nsIEditor.pasteTransferable won't insert image/png if nsITransaferable uses nsIInputStream. r=masayuki!

editor.pastedTransferable cannot insert image/png when using nsITransaferable.

Although pastedTransferable stores DataTransfer in stack, when mime type is
image/png, DataTransfer fetches all data in
DataTransferItem::FillInExternalData then stores it as KIND_FILE.
It means that nsIInputStream in nsITransferable is already EOF.

So we should use InsertFromDataTransfer when internal data moves to
DataTransfer.

Comment 2

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/4da3a6002a66
nsIEditor.pasteTransferable won't insert image/png if nsITransaferable uses nsIInputStream. r=masayuki

Comment 3

[Cristian Brindusan [:cbrindusan]]

https://hg.mozilla.org/mozilla-central/rev/4da3a6002a66