This also comes with some small cleanups regarding
XPath::Evaluator#node_matches?. This change removes the need to, every time,
also use can_match_node?() to prevent NoMethodError errors from popping up.
The previous commit was nonsense as I didn't understand XPath's "following" axis
properly. This commit introduces proper tests and a note for future me so that I
can implement it properly.
When parsing a bare node test such as "A" this is now parsed as following:
(axis "child" (test nil "A"))
Instead of this:
(test nil "A")
According to the XPath specification both are identical and this simplifies some
of the code in the XPath evaluator.
Upon further investigation this change turned out to be useless. Nokogiri/libxml
does not allow the use of long axes without tests, instead it ends up
lexing/parsing such a value as a simple node test.
This reverts commit f699b0d097.
An axes such as "." is the same as "self::node()". To simplify things on
parser/evaluator level we'll emit the corresponding tokens for a "node()"
function call for these axes.
Instead of using a raw Hash Oga now uses the XML::Attribute class for storing
information about element attributes.
Attributes are stored as an Array of XML::Attribute instances. This allows the
attributes to be more easily modified. If they were stored as a Hash you'd not
only have to update the attributes themselves but also the Hash that contains
them.
While using an Array has a slight runtime cost in most cases the amount of
attributes is small enough that this doesn't really pose a problem. If webscale
performance is desired at some point in the future Oga could most likely cache
the lookup of an attribute. This however is something for the future.
This method can be used to retrieve the text of the given node only. In other
words, unlike Element#text it does not contain the text of any child nodes.
This method uses a loop to traverse upwards the DOM tree in order to find the
root document/element. While this might have an impact on performance I don't
expect Oga itself to call this method very often. The benefit is that Node
instances don't require users to manually pass the top level document as an
argument.