As it was discussed in this forum thread and reported in XRENDERING-670, we have an inconsistency between CKEditor and XWiki syntax: CKEditor allows adding a link to an image when that image has a caption but this cannot be represented in XWiki syntax.
My proposal is to represent this as
[[~[~[Caption Content~>~>image:Sandbox.WebHome@XWikiLogo.png~]~]>>doc:Sandbox.TestPage2]]
in XWiki syntax, so basically we would nest the captioned image in a link. The idea is to only recognize this if the captioned image is the only content of the link, otherwise this will be treated as a regular link and the caption will be lost. Similarly, only if the figure contains just a link with a nested image, it is transformed into this XWiki syntax.
I don’t like how this is further reversing the nesting of the elements, but given the current syntax and the current parser (which shouldn’t be changed for backwards compatibility reasons), this seems the only logical and somehow nice syntax.
An alternative would be to store the information of the link in attributes of the image (there could be an attribute for the reference and a prefix to store all other attributes), but this seems much less logical and would probably require a lot more extra code.
The escaping on the nested image syntax is required, as otherwise the parser doesn’t recognize it (the parser doesn’t accept nested links, the link label is parsed in a sub-parser after removing one level of escaping).
My proposal is to implement this for 15.5 and also backport it to 14.10.x. I would either backport it directly if the fix looks simple enough or wait until 15.5 has been out for at least two weeks to ensure some testing happened.
Any opinions, also on the question of backporting?