golang.org/x/net/html.ParseFragmentWithOptions initializes its form
pointer based on whether the context element or any of its ancestors
is a form element. If the context has a form ancestor, nested form tags
are discarded per HTML parsing rules.
Previously, cachedParseHtmlWithContext keyed cached fragments strictly
by context tag name. When a selection contained targets both inside and
outside forms sharing the same tag name, the first visited target cached
its parsed fragment, leading to incorrect parsing for subsequent targets
under the other form-ancestor state.
Differentiate the fragment cache key by appending a form-ancestor
indicator when context or any of its ancestors is a form element.
Fixes#614
Node caching was still using the node type instead of the node name in a
few places. Updated those to also use the node name as the cache key.
ReplaceWithHtml and PrependHtml inserted parsed nodes in the wrong
order. Kept track of the correct parent to fix this.
Use correct parent flag for SetHtml
* SetHml remains unchanged, see comment on the isParent param of
eachNodeHtml
* Removed unused functions
* Added documentation on eachNodeHtml
* Fixed node parsing cache keys and added test
* Refactored some tests for clarity
AdamMagued