Using the benchmark xpath/evaluator/node_matches_bench.rb the results
prior to this commit were as following for 3 cases:
name only: 737633 i/s
namespace wildcard: 612196 i/s
name wildcard: 516030 i/s
With this commit said numbers have changed to the following:
name only: 746086 i/s
namespace wildcard: 1097168 i/s
name wildcard: 1151255 i/s
This results in the following increase of performance for each case:
name only: 1,011x (insignificant)
namespace wildcard: 1,79x
name wildcard: 2,23x
In the benchmark xpath/evaluator/big_xml_average_bench.rb the difference
isn't really noticable as said benchmark only queries elements by names,
of which the performance hasn't really improved.
This ensures that HTML such as this:
<li>foo
<li>bar
is parsed as this:
<li>foo</li>
<li>bar</li>
and not as this:
<li>
foo
<li>bar</li>
</li>
Fixes#97
This makes it easier to automatically insert preceding tokens when
starting a new element as we now have access to the name. Previously
on_element_start would be invoked first which doesn't receive an
argument.
The XML/HTML lexer is now capable of processing most invalid XML/HTML
(that I can think of at least). This is achieved by inserting missing
closing tags (where needed) and/or ignoring excessive closing tags. For
example, HTML such as this:
<a></a></p>
Results in the following tokens:
[:T_ELEM_START, nil, 1]
[:T_ELEM_NAME, 'a', 1]
[:T_ELEM_CLOSE, nil, 1]
In turn this HTML:
<a>
Results in these tokens:
[:T_ELEM_START, nil, 1]
[:T_ELEM_NAME, 'a', 1]
[:T_ELEM_CLOSE, nil, 1]
Fixes#84
Previously a single Ragel machine was used for processing HTML
script and style tags. This had the unfortunate side-effect that the
following was not parsed correctly (while being valid HTML):
<script>
var foo = "</style>";
</script>
The same applied to style tags:
<style>
/* </script> */
</style>
By using separate machines we can work around the above issue. The
downside is that this can produce multiple T_TEXT nodes, which have to
be stitched back together in the parser.
This adds lexing support for HTML/XML such as:
<foo bar="""></foo>
While technically invalid, some websites (e.g. yahoo.com) contain HTML
just like this.
The lexer handles this as following:
1. When we're in the "element_head" machine, do business as usual until
we bump into a "=".
2. Call (using Ragel's "fcall") the machine to use for processing the
attribute value (if any).
3. In this machine quoted strings are processed. The moment a string has
been processed the lexer jumps right back in to the "element_head"
machine. This ensures that any stray quotes are ignored instead of
being processed as extra attribute values (eventually leading to
parsing errors due to unbalanced quotes).
Similar to comments (ea8b4aa92f) and CDATA
tags (8acc7fc743) processing instructions
are now lexed in separate chunks _with_ proper support for streaming
input.
Related issue: #93
Instead of using a single token (T_CDATA) for a CDATA tag the lexer now
uses 3 tokens:
1. T_CDATA_START
2. T_CDATA_BODY
3. T_CDATA_END
The T_CDATA_BODY token can occur multiple times and is turned into a
single value in the XML parser. This is similar to the way strings are
lexed.
By changing the way CDATA tags are lexed Oga can now lex CDATA tags
containing newlines when using an IO as input. For example, this would
previously fail:
Oga.parse_xml(StringIO.new("<![CDATA[\nfoo]]>"))
Because IO input reads input per line the input for the lexer would be
as following:
"<![CDATA[\n"
"foo]]>"
Related issues: #93
This cache is flushed whenever Element#register_namespace is called.
When this cache is flushed it's also recursively flushed for all child
elements. This makes calls to Element#register_namespace a bit more
expensive but in turn calls to Element#available_namespaces will be a
lot faster.
The results of these methods is now cached until a Node is moved into
another NodeSet. This reduces the time spent in the
xpath/evaluator/big_xml_average_bench.rb benchmark from roughly 10
seconds to roughly 5 seconds per iteration.
In HTML the text of a script/style tag should be left untouched, no
entities must be converted. Doing so would break Javascript such as the
following:
foo&&bar;
Such code is often the result of minifiers doing their dirty business.
This was broken by introducing the process of lazy decoding of XML/HTML
entities. The new setup works similar to how XML::Text#text decodes any
entities that may be present.
Fixes#91
When querying an XML document that explicitly defines the default XML
namespace the XPath evaluator now correctly matches all nodes within
that namespace if no namespace prefix is given in the query. Previously
this would always return an empty set.
Yorick Peterse
Andrei Botalov