XMLDB/simpletest/parser.php

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<?php
/**
* base include file for SimpleTest
* @package SimpleTest
* @subpackage MockObjects
* @version $Id: parser.php 1723 2008-04-08 00:34:10Z lastcraft $
*/
/**#@+
* Lexer mode stack constants
*/
foreach (array('LEXER_ENTER', 'LEXER_MATCHED',
'LEXER_UNMATCHED', 'LEXER_EXIT',
'LEXER_SPECIAL') as $i => $constant) {
if (! defined($constant)) {
define($constant, $i + 1);
}
}
/**#@-*/
/**
* Compounded regular expression. Any of
* the contained patterns could match and
* when one does, it's label is returned.
* @package SimpleTest
* @subpackage WebTester
*/
class ParallelRegex {
var $_patterns;
var $_labels;
var $_regex;
var $_case;
/**
* Constructor. Starts with no patterns.
* @param boolean $case True for case sensitive, false
* for insensitive.
* @access public
*/
function ParallelRegex($case) {
$this->_case = $case;
$this->_patterns = array();
$this->_labels = array();
$this->_regex = null;
}
/**
* Adds a pattern with an optional label.
* @param string $pattern Perl style regex, but ( and )
* lose the usual meaning.
* @param string $label Label of regex to be returned
* on a match.
* @access public
*/
function addPattern($pattern, $label = true) {
$count = count($this->_patterns);
$this->_patterns[$count] = $pattern;
$this->_labels[$count] = $label;
$this->_regex = null;
}
/**
* Attempts to match all patterns at once against
* a string.
* @param string $subject String to match against.
* @param string $match First matched portion of
* subject.
* @return boolean True on success.
* @access public
*/
function match($subject, &$match) {
if (count($this->_patterns) == 0) {
return false;
}
if (! preg_match($this->_getCompoundedRegex(), $subject, $matches)) {
$match = '';
return false;
}
$match = $matches[0];
for ($i = 1; $i < count($matches); $i++) {
if ($matches[$i]) {
return $this->_labels[$i - 1];
}
}
return true;
}
/**
* Compounds the patterns into a single
* regular expression separated with the
* "or" operator. Caches the regex.
* Will automatically escape (, ) and / tokens.
* @param array $patterns List of patterns in order.
* @access private
*/
function _getCompoundedRegex() {
if ($this->_regex == null) {
for ($i = 0, $count = count($this->_patterns); $i < $count; $i++) {
$this->_patterns[$i] = '(' . str_replace(
array('/', '(', ')'),
array('\/', '\(', '\)'),
$this->_patterns[$i]) . ')';
}
$this->_regex = "/" . implode("|", $this->_patterns) . "/" . $this->_getPerlMatchingFlags();
}
return $this->_regex;
}
/**
* Accessor for perl regex mode flags to use.
* @return string Perl regex flags.
* @access private
*/
function _getPerlMatchingFlags() {
return ($this->_case ? "msS" : "msSi");
}
}
/**
* States for a stack machine.
* @package SimpleTest
* @subpackage WebTester
*/
class SimpleStateStack {
var $_stack;
/**
* Constructor. Starts in named state.
* @param string $start Starting state name.
* @access public
*/
function SimpleStateStack($start) {
$this->_stack = array($start);
}
/**
* Accessor for current state.
* @return string State.
* @access public
*/
function getCurrent() {
return $this->_stack[count($this->_stack) - 1];
}
/**
* Adds a state to the stack and sets it
* to be the current state.
* @param string $state New state.
* @access public
*/
function enter($state) {
array_push($this->_stack, $state);
}
/**
* Leaves the current state and reverts
* to the previous one.
* @return boolean False if we drop off
* the bottom of the list.
* @access public
*/
function leave() {
if (count($this->_stack) == 1) {
return false;
}
array_pop($this->_stack);
return true;
}
}
/**
* Accepts text and breaks it into tokens.
* Some optimisation to make the sure the
* content is only scanned by the PHP regex
* parser once. Lexer modes must not start
* with leading underscores.
* @package SimpleTest
* @subpackage WebTester
*/
class SimpleLexer {
var $_regexes;
var $_parser;
var $_mode;
var $_mode_handlers;
var $_case;
/**
* Sets up the lexer in case insensitive matching
* by default.
* @param SimpleSaxParser $parser Handling strategy by
* reference.
* @param string $start Starting handler.
* @param boolean $case True for case sensitive.
* @access public
*/
function SimpleLexer(&$parser, $start = "accept", $case = false) {
$this->_case = $case;
$this->_regexes = array();
$this->_parser = &$parser;
$this->_mode = &new SimpleStateStack($start);
$this->_mode_handlers = array($start => $start);
}
/**
* Adds a token search pattern for a particular
* parsing mode. The pattern does not change the
* current mode.
* @param string $pattern Perl style regex, but ( and )
* lose the usual meaning.
* @param string $mode Should only apply this
* pattern when dealing with
* this type of input.
* @access public
*/
function addPattern($pattern, $mode = "accept") {
if (! isset($this->_regexes[$mode])) {
$this->_regexes[$mode] = new ParallelRegex($this->_case);
}
$this->_regexes[$mode]->addPattern($pattern);
if (! isset($this->_mode_handlers[$mode])) {
$this->_mode_handlers[$mode] = $mode;
}
}
/**
* Adds a pattern that will enter a new parsing
* mode. Useful for entering parenthesis, strings,
* tags, etc.
* @param string $pattern Perl style regex, but ( and )
* lose the usual meaning.
* @param string $mode Should only apply this
* pattern when dealing with
* this type of input.
* @param string $new_mode Change parsing to this new
* nested mode.
* @access public
*/
function addEntryPattern($pattern, $mode, $new_mode) {
if (! isset($this->_regexes[$mode])) {
$this->_regexes[$mode] = new ParallelRegex($this->_case);
}
$this->_regexes[$mode]->addPattern($pattern, $new_mode);
if (! isset($this->_mode_handlers[$new_mode])) {
$this->_mode_handlers[$new_mode] = $new_mode;
}
}
/**
* Adds a pattern that will exit the current mode
* and re-enter the previous one.
* @param string $pattern Perl style regex, but ( and )
* lose the usual meaning.
* @param string $mode Mode to leave.
* @access public
*/
function addExitPattern($pattern, $mode) {
if (! isset($this->_regexes[$mode])) {
$this->_regexes[$mode] = new ParallelRegex($this->_case);
}
$this->_regexes[$mode]->addPattern($pattern, "__exit");
if (! isset($this->_mode_handlers[$mode])) {
$this->_mode_handlers[$mode] = $mode;
}
}
/**
* Adds a pattern that has a special mode. Acts as an entry
* and exit pattern in one go, effectively calling a special
* parser handler for this token only.
* @param string $pattern Perl style regex, but ( and )
* lose the usual meaning.
* @param string $mode Should only apply this
* pattern when dealing with
* this type of input.
* @param string $special Use this mode for this one token.
* @access public
*/
function addSpecialPattern($pattern, $mode, $special) {
if (! isset($this->_regexes[$mode])) {
$this->_regexes[$mode] = new ParallelRegex($this->_case);
}
$this->_regexes[$mode]->addPattern($pattern, "_$special");
if (! isset($this->_mode_handlers[$special])) {
$this->_mode_handlers[$special] = $special;
}
}
/**
* Adds a mapping from a mode to another handler.
* @param string $mode Mode to be remapped.
* @param string $handler New target handler.
* @access public
*/
function mapHandler($mode, $handler) {
$this->_mode_handlers[$mode] = $handler;
}
/**
* Splits the page text into tokens. Will fail
* if the handlers report an error or if no
* content is consumed. If successful then each
* unparsed and parsed token invokes a call to the
* held listener.
* @param string $raw Raw HTML text.
* @return boolean True on success, else false.
* @access public
*/
function parse($raw) {
if (! isset($this->_parser)) {
return false;
}
$length = strlen($raw);
while (is_array($parsed = $this->_reduce($raw))) {
list($raw, $unmatched, $matched, $mode) = $parsed;
if (! $this->_dispatchTokens($unmatched, $matched, $mode)) {
return false;
}
if ($raw === '') {
return true;
}
if (strlen($raw) == $length) {
return false;
}
$length = strlen($raw);
}
if (! $parsed) {
return false;
}
return $this->_invokeParser($raw, LEXER_UNMATCHED);
}
/**
* Sends the matched token and any leading unmatched
* text to the parser changing the lexer to a new
* mode if one is listed.
* @param string $unmatched Unmatched leading portion.
* @param string $matched Actual token match.
* @param string $mode Mode after match. A boolean
* false mode causes no change.
* @return boolean False if there was any error
* from the parser.
* @access private
*/
function _dispatchTokens($unmatched, $matched, $mode = false) {
if (! $this->_invokeParser($unmatched, LEXER_UNMATCHED)) {
return false;
}
if (is_bool($mode)) {
return $this->_invokeParser($matched, LEXER_MATCHED);
}
if ($this->_isModeEnd($mode)) {
if (! $this->_invokeParser($matched, LEXER_EXIT)) {
return false;
}
return $this->_mode->leave();
}
if ($this->_isSpecialMode($mode)) {
$this->_mode->enter($this->_decodeSpecial($mode));
if (! $this->_invokeParser($matched, LEXER_SPECIAL)) {
return false;
}
return $this->_mode->leave();
}
$this->_mode->enter($mode);
return $this->_invokeParser($matched, LEXER_ENTER);
}
/**
* Tests to see if the new mode is actually to leave
* the current mode and pop an item from the matching
* mode stack.
* @param string $mode Mode to test.
* @return boolean True if this is the exit mode.
* @access private
*/
function _isModeEnd($mode) {
return ($mode === "__exit");
}
/**
* Test to see if the mode is one where this mode
* is entered for this token only and automatically
* leaves immediately afterwoods.
* @param string $mode Mode to test.
* @return boolean True if this is the exit mode.
* @access private
*/
function _isSpecialMode($mode) {
return (strncmp($mode, "_", 1) == 0);
}
/**
* Strips the magic underscore marking single token
* modes.
* @param string $mode Mode to decode.
* @return string Underlying mode name.
* @access private
*/
function _decodeSpecial($mode) {
return substr($mode, 1);
}
/**
* Calls the parser method named after the current
* mode. Empty content will be ignored. The lexer
* has a parser handler for each mode in the lexer.
* @param string $content Text parsed.
* @param boolean $is_match Token is recognised rather
* than unparsed data.
* @access private
*/
function _invokeParser($content, $is_match) {
if (($content === '') || ($content === false)) {
return true;
}
$handler = $this->_mode_handlers[$this->_mode->getCurrent()];
return $this->_parser->$handler($content, $is_match);
}
/**
* Tries to match a chunk of text and if successful
* removes the recognised chunk and any leading
* unparsed data. Empty strings will not be matched.
* @param string $raw The subject to parse. This is the
* content that will be eaten.
* @return array/boolean Three item list of unparsed
* content followed by the
* recognised token and finally the
* action the parser is to take.
* True if no match, false if there
* is a parsing error.
* @access private
*/
function _reduce($raw) {
if ($action = $this->_regexes[$this->_mode->getCurrent()]->match($raw, $match)) {
$unparsed_character_count = strpos($raw, $match);
$unparsed = substr($raw, 0, $unparsed_character_count);
$raw = substr($raw, $unparsed_character_count + strlen($match));
return array($raw, $unparsed, $match, $action);
}
return true;
}
}
/**
* Breaks HTML into SAX events.
* @package SimpleTest
* @subpackage WebTester
*/
class SimpleHtmlLexer extends SimpleLexer {
/**
* Sets up the lexer with case insensitive matching
* and adds the HTML handlers.
* @param SimpleSaxParser $parser Handling strategy by
* reference.
* @access public
*/
function SimpleHtmlLexer(&$parser) {
$this->SimpleLexer($parser, 'text');
$this->mapHandler('text', 'acceptTextToken');
$this->_addSkipping();
foreach ($this->_getParsedTags() as $tag) {
$this->_addTag($tag);
}
$this->_addInTagTokens();
}
/**
* List of parsed tags. Others are ignored.
* @return array List of searched for tags.
* @access private
*/
function _getParsedTags() {
return array('a', 'base', 'title', 'form', 'input', 'button', 'textarea', 'select',
'option', 'frameset', 'frame', 'label');
}
/**
* The lexer has to skip certain sections such
* as server code, client code and styles.
* @access private
*/
function _addSkipping() {
$this->mapHandler('css', 'ignore');
$this->addEntryPattern('<style', 'text', 'css');
$this->addExitPattern('</style>', 'css');
$this->mapHandler('js', 'ignore');
$this->addEntryPattern('<script', 'text', 'js');
$this->addExitPattern('</script>', 'js');
$this->mapHandler('comment', 'ignore');
$this->addEntryPattern('<!--', 'text', 'comment');
$this->addExitPattern('-->', 'comment');
}
/**
* Pattern matches to start and end a tag.
* @param string $tag Name of tag to scan for.
* @access private
*/
function _addTag($tag) {
$this->addSpecialPattern("</$tag>", 'text', 'acceptEndToken');
$this->addEntryPattern("<$tag", 'text', 'tag');
}
/**
* Pattern matches to parse the inside of a tag
* including the attributes and their quoting.
* @access private
*/
function _addInTagTokens() {
$this->mapHandler('tag', 'acceptStartToken');
$this->addSpecialPattern('\s+', 'tag', 'ignore');
$this->_addAttributeTokens();
$this->addExitPattern('/>', 'tag');
$this->addExitPattern('>', 'tag');
}
/**
* Matches attributes that are either single quoted,
* double quoted or unquoted.
* @access private
*/
function _addAttributeTokens() {
$this->mapHandler('dq_attribute', 'acceptAttributeToken');
$this->addEntryPattern('=\s*"', 'tag', 'dq_attribute');
$this->addPattern("\\\\\"", 'dq_attribute');
$this->addExitPattern('"', 'dq_attribute');
$this->mapHandler('sq_attribute', 'acceptAttributeToken');
$this->addEntryPattern("=\s*'", 'tag', 'sq_attribute');
$this->addPattern("\\\\'", 'sq_attribute');
$this->addExitPattern("'", 'sq_attribute');
$this->mapHandler('uq_attribute', 'acceptAttributeToken');
$this->addSpecialPattern('=\s*[^>\s]*', 'tag', 'uq_attribute');
}
}
/**
* Converts HTML tokens into selected SAX events.
* @package SimpleTest
* @subpackage WebTester
*/
class SimpleHtmlSaxParser {
var $_lexer;
var $_listener;
var $_tag;
var $_attributes;
var $_current_attribute;
/**
* Sets the listener.
* @param SimpleSaxListener $listener SAX event handler.
* @access public
*/
function SimpleHtmlSaxParser(&$listener) {
$this->_listener = &$listener;
$this->_lexer = &$this->createLexer($this);
$this->_tag = '';
$this->_attributes = array();
$this->_current_attribute = '';
}
/**
* Runs the content through the lexer which
* should call back to the acceptors.
* @param string $raw Page text to parse.
* @return boolean False if parse error.
* @access public
*/
function parse($raw) {
return $this->_lexer->parse($raw);
}
/**
* Sets up the matching lexer. Starts in 'text' mode.
* @param SimpleSaxParser $parser Event generator, usually $self.
* @return SimpleLexer Lexer suitable for this parser.
* @access public
* @static
*/
function &createLexer(&$parser) {
$lexer = &new SimpleHtmlLexer($parser);
return $lexer;
}
/**
* Accepts a token from the tag mode. If the
* starting element completes then the element
* is dispatched and the current attributes
* set back to empty. The element or attribute
* name is converted to lower case.
* @param string $token Incoming characters.
* @param integer $event Lexer event type.
* @return boolean False if parse error.
* @access public
*/
function acceptStartToken($token, $event) {
if ($event == LEXER_ENTER) {
$this->_tag = strtolower(substr($token, 1));
return true;
}
if ($event == LEXER_EXIT) {
$success = $this->_listener->startElement(
$this->_tag,
$this->_attributes);
$this->_tag = '';
$this->_attributes = array();
return $success;
}
if ($token != '=') {
$this->_current_attribute = strtolower(SimpleHtmlSaxParser::decodeHtml($token));
$this->_attributes[$this->_current_attribute] = '';
}
return true;
}
/**
* Accepts a token from the end tag mode.
* The element name is converted to lower case.
* @param string $token Incoming characters.
* @param integer $event Lexer event type.
* @return boolean False if parse error.
* @access public
*/
function acceptEndToken($token, $event) {
if (! preg_match('/<\/(.*)>/', $token, $matches)) {
return false;
}
return $this->_listener->endElement(strtolower($matches[1]));
}
/**
* Part of the tag data.
* @param string $token Incoming characters.
* @param integer $event Lexer event type.
* @return boolean False if parse error.
* @access public
*/
function acceptAttributeToken($token, $event) {
if ($this->_current_attribute) {
if ($event == LEXER_UNMATCHED) {
$this->_attributes[$this->_current_attribute] .=
SimpleHtmlSaxParser::decodeHtml($token);
}
if ($event == LEXER_SPECIAL) {
$this->_attributes[$this->_current_attribute] .=
preg_replace('/^=\s*/' , '', SimpleHtmlSaxParser::decodeHtml($token));
}
}
return true;
}
/**
* A character entity.
* @param string $token Incoming characters.
* @param integer $event Lexer event type.
* @return boolean False if parse error.
* @access public
*/
function acceptEntityToken($token, $event) {
}
/**
* Character data between tags regarded as
* important.
* @param string $token Incoming characters.
* @param integer $event Lexer event type.
* @return boolean False if parse error.
* @access public
*/
function acceptTextToken($token, $event) {
return $this->_listener->addContent($token);
}
/**
* Incoming data to be ignored.
* @param string $token Incoming characters.
* @param integer $event Lexer event type.
* @return boolean False if parse error.
* @access public
*/
function ignore($token, $event) {
return true;
}
/**
* Decodes any HTML entities.
* @param string $html Incoming HTML.
* @return string Outgoing plain text.
* @access public
* @static
*/
function decodeHtml($html) {
return html_entity_decode($html, ENT_QUOTES);
}
/**
* Turns HTML into text browser visible text. Images
* are converted to their alt text and tags are supressed.
* Entities are converted to their visible representation.
* @param string $html HTML to convert.
* @return string Plain text.
* @access public
* @static
*/
function normalise($html) {
$text = preg_replace('|<!--.*?-->|', '', $html);
$text = preg_replace('|<script[^>]*>.*?</script>|', '', $text);
$text = preg_replace('|<img[^>]*alt\s*=\s*"([^"]*)"[^>]*>|', ' \1 ', $text);
$text = preg_replace('|<img[^>]*alt\s*=\s*\'([^\']*)\'[^>]*>|', ' \1 ', $text);
$text = preg_replace('|<img[^>]*alt\s*=\s*([a-zA-Z_]+)[^>]*>|', ' \1 ', $text);
$text = preg_replace('|<[^>]*>|', '', $text);
$text = SimpleHtmlSaxParser::decodeHtml($text);
$text = preg_replace('|\s+|', ' ', $text);
return trim(trim($text), "\xA0"); // TODO: The \xAO is a &nbsp;. Add a test for this.
}
}
/**
* SAX event handler.
* @package SimpleTest
* @subpackage WebTester
* @abstract
*/
class SimpleSaxListener {
/**
* Sets the document to write to.
* @access public
*/
function SimpleSaxListener() {
}
/**
* Start of element event.
* @param string $name Element name.
* @param hash $attributes Name value pairs.
* Attributes without content
* are marked as true.
* @return boolean False on parse error.
* @access public
*/
function startElement($name, $attributes) {
}
/**
* End of element event.
* @param string $name Element name.
* @return boolean False on parse error.
* @access public
*/
function endElement($name) {
}
/**
* Unparsed, but relevant data.
* @param string $text May include unparsed tags.
* @return boolean False on parse error.
* @access public
*/
function addContent($text) {
}
}
?>