Support for xml:space="preserve"

[xavier]

It appears that Saxy doesn't support the xml:space="preserve" attribute and fails to emit character data for an element containing only whitespace.

Here's a test which illustrates the issue and the expected behavior:

test "parses elements with xml:space=\"preserve\"" do
  buffer = "<foo xml:space=\"preserve\">   </foo>"

  assert {:ok, state} = parse(buffer)
  events = Enum.reverse(state.user_state)

  assert [{:start_element, {"foo", [{"xml:space", "preserve"}]}} | events] = events
  assert [{:characters, "   "} | events] = events
  assert [{:end_element, "foo"} | events] = events
  assert [{:end_document, {}} | events] = events

  assert events == []
end

Note that this is a trivial case as the behavior dictated by xml:space is supposed to be inherited by child nodes.

I had a look at parser/element.ex and it seems like supporting such stateful behavior might be challenging.
Perhaps could we work around the issue by allowing some level of customization of whitespace handling as an option to the parse functions?

[qcam]

Thanks for the report! It seems like it's a bug if Saxy doesn't emit the :characters event for this case. White spaces won't be trimmed by the parser and it's up to the application to decide what to do with it.

I will take a look into this.