/jssource/Minifier.php
PHP | 459 lines | 251 code | 61 blank | 147 comment | 48 complexity | 715c5d44e0fc304857e1f466fc20533e MD5 | raw file
- <?php
- /**
- * JShrink
- *
- * Copyright (c) 2009-2012, Robert Hafner <tedivm@tedivm.com>.
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- *
- * * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *
- * * Redistributions in binary form must reproduce the above copyright
- * notice, this list of conditions and the following disclaimer in
- * the documentation and/or other materials provided with the
- * distribution.
- *
- * * Neither the name of Robert Hafner nor the names of his
- * contributors may be used to endorse or promote products derived
- * from this software without specific prior written permission.
- *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
- * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
- * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
- * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
- * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
- * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
- * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
- * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
- * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
- * POSSIBILITY OF SUCH DAMAGE.
- *
- * @package JShrink
- * @author Robert Hafner <tedivm@tedivm.com>
- * @copyright 2009-2012 Robert Hafner <tedivm@tedivm.com>
- * @license http://www.opensource.org/licenses/bsd-license.php BSD License
- * @link https://github.com/tedivm/JShrink
- * @version Release: 0.4
- */
- // Some changes done by Akshay Joshi to preserve compatibility with PHP 5.2.
- /**
- * Minifier
- *
- * Usage - Minifier::minify($js);
- * Usage - Minifier::minify($js, $options);
- * Usage - Minifier::minify($js, array('flaggedComments' => false));
- *
- * @version 0.4
- * @package JShrink
- * @author Robert Hafner <tedivm@tedivm.com>
- * @license http://www.opensource.org/licenses/bsd-license.php BSD License
- */
- class Minifier
- {
- /**
- * The input javascript to be minified.
- *
- * @var string
- */
- protected $input;
- /**
- * The location of the character (in the input string) that is next to be processed.
- *
- * @var int
- */
- protected $index = 0;
- /**
- * The first of the characters currently being looked at.
- *
- * @var string
- */
- protected $a = '';
- /**
- * The next character being looked at (after a);
- *
- * @var string
- */
- protected $b = '';
- /**
- * This character is only active when certain look ahead actions take place.
- *
- * @var string
- */
- protected $c;
- /**
- * Contains the options for the current minification process.
- *
- * @var array
- */
- protected $options;
- /**
- * Contains the default options for minification. This array is merged with the one passed in by the user to create
- * the request specific set of options (stored in the $options attribute).
- *
- * @var array
- */
- static protected $defaultOptions = array('flaggedComments' => true);
- /**
- * Contains a copy of the JShrink object used to run minification. This is only used internally, and is only stored
- * for performance reasons. There is no internal data shared between minification requests.
- */
- static protected $jshrink;
- /**
- * Minifier::minify takes a string containing javascript and removes unneeded characters in order to shrink the code
- * without altering it's functionality.
- */
- static public function minify($js, $options = array())
- {
- try{
- ob_start();
- $currentOptions = array_merge(self::$defaultOptions, $options);
- if(!isset(self::$jshrink))
- self::$jshrink = new Minifier();
- self::$jshrink->breakdownScript($js, $currentOptions);
- return ob_get_clean();
- }catch(Exception $e){
- if(isset(self::$jshrink))
- self::$jshrink->clean();
- ob_end_clean();
- throw $e;
- }
- }
- /**
- * Processes a javascript string and outputs only the required characters, stripping out all unneeded characters.
- *
- * @param string $js The raw javascript to be minified
- * @param array $currentOptions Various runtime options in an associative array
- */
- protected function breakdownScript($js, $currentOptions)
- {
- // reset work attributes in case this isn't the first run.
- $this->clean();
- $this->options = $currentOptions;
- $js = str_replace("\r\n", "\n", $js);
- $this->input = str_replace("\r", "\n", $js);
- $this->input = preg_replace('/\h/u', ' ', $this->input);
- $this->a = $this->getReal();
- // the only time the length can be higher than 1 is if a conditional comment needs to be displayed
- // and the only time that can happen for $a is on the very first run
- while(strlen($this->a) > 1)
- {
- echo $this->a;
- $this->a = $this->getReal();
- }
- $this->b = $this->getReal();
- while($this->a !== false && !is_null($this->a) && $this->a !== '')
- {
- // now we give $b the same check for conditional comments we gave $a before we began looping
- if(strlen($this->b) > 1)
- {
- echo $this->a . $this->b;
- $this->a = $this->getReal();
- $this->b = $this->getReal();
- continue;
- }
- switch($this->a)
- {
- // new lines
- case "\n":
- // if the next line is something that can't stand alone preserve the newline
- if($this->b != '' && strpos('(-+{[@', $this->b) !== false)
- {
- echo $this->a;
- $this->saveString();
- break;
- }
- // if its a space we move down to the string test below
- if($this->b === ' ')
- break;
- // otherwise we treat the newline like a space
- case ' ':
- if(self::isAlphaNumeric($this->b))
- echo $this->a;
- $this->saveString();
- break;
- default:
- switch($this->b)
- {
- case "\n":
- if(strpos('}])+-"\'', $this->a) !== false)
- {
- echo $this->a;
- $this->saveString();
- break;
- }else{
- if(self::isAlphaNumeric($this->a))
- {
- echo $this->a;
- $this->saveString();
- }
- }
- break;
- case ' ':
- if(!self::isAlphaNumeric($this->a))
- break;
- default:
- // check for some regex that breaks stuff
- if($this->a == '/' && ($this->b == '\'' || $this->b == '"'))
- {
- $this->saveRegex();
- continue;
- }
- echo $this->a;
- $this->saveString();
- break;
- }
- }
- // do reg check of doom
- $this->b = $this->getReal();
- if(($this->b == '/' && strpos('(,=:[!&|?', $this->a) !== false))
- $this->saveRegex();
- }
- $this->clean();
- }
- /**
- * Returns the next string for processing based off of the current index.
- *
- * @return string
- */
- protected function getChar()
- {
- if(isset($this->c))
- {
- $char = $this->c;
- unset($this->c);
- }else{
- $tchar = substr($this->input, $this->index, 1);
- if(isset($tchar) && $tchar !== false)
- {
- $char = $tchar;
- $this->index++;
- }else{
- return false;
- }
- }
- if($char !== "\n" && ord($char) < 32)
- return ' ';
- return $char;
- }
- /**
- * This function gets the next "real" character. It is essentially a wrapper around the getChar function that skips
- * comments. This has signifigant peformance benefits as the skipping is done using native functions (ie, c code)
- * rather than in script php.
- *
- * @return string Next 'real' character to be processed.
- */
- protected function getReal()
- {
- $startIndex = $this->index;
- $char = $this->getChar();
- if($char == '/')
- {
- $this->c = $this->getChar();
- if($this->c == '/')
- {
- $thirdCommentString = substr($this->input, $this->index, 1);
- // kill rest of line
- $char = $this->getNext("\n");
- if($thirdCommentString == '@')
- {
- $endPoint = ($this->index) - $startIndex;
- unset($this->c);
- $char = "\n" . substr($this->input, $startIndex, $endPoint);// . "\n";
- }else{
- $char = $this->getChar();
- $char = $this->getChar();
- }
- }elseif($this->c == '*'){
- $this->getChar(); // current C
- $thirdCommentString = $this->getChar();
- if($thirdCommentString == '@')
- {
- // conditional comment
- // we're gonna back up a bit and and send the comment back, where the first
- // char will be echoed and the rest will be treated like a string
- $this->index = $this->index-2;
- return '/';
- }elseif($this->getNext('*/')){
- // kill everything up to the next */
- $this->getChar(); // get *
- $this->getChar(); // get /
- $char = $this->getChar(); // get next real character
- // if YUI-style comments are enabled we reinsert it into the stream
- if($this->options['flaggedComments'] && $thirdCommentString == '!')
- {
- $endPoint = ($this->index - 1) - $startIndex;
- echo "\n" . substr($this->input, $startIndex, $endPoint) . "\n";
- }
- }else{
- $char = false;
- }
- if($char === false)
- throw new RuntimeException('Stray comment. ' . $this->index);
- // if we're here c is part of the comment and therefore tossed
- if(isset($this->c))
- unset($this->c);
- }
- }
- return $char;
- }
- /**
- * Pushes the index ahead to the next instance of the supplied string. If it is found the first character of the
- * string is returned.
- *
- * @return string|false Returns the first character of the string if found, false otherwise.
- */
- protected function getNext($string)
- {
- $pos = strpos($this->input, $string, $this->index);
- if($pos === false)
- return false;
- $this->index = $pos;
- return substr($this->input, $this->index, 1);
- }
- /**
- * When a javascript string is detected this function crawls for the end of it and saves the whole string.
- *
- */
- protected function saveString()
- {
- $this->a = $this->b;
- if($this->a == "'" || $this->a == '"') // is the character a quote
- {
- // save literal string
- $stringType = $this->a;
- while(1)
- {
- echo $this->a;
- $this->a = $this->getChar();
- switch($this->a)
- {
- case $stringType:
- break 2;
- case "\n":
- throw new RuntimeException('Unclosed string. ' . $this->index);
- break;
- case '\\':
- echo $this->a;
- $this->a = $this->getChar();
- }
- }
- }
- }
- /**
- * When a regular expression is detected this funcion crawls for the end of it and saves the whole regex.
- */
- protected function saveRegex()
- {
- echo $this->a . $this->b;
- while(($this->a = $this->getChar()) !== false)
- {
- if($this->a == '/')
- break;
- if($this->a == '\\')
- {
- echo $this->a;
- $this->a = $this->getChar();
- }
- if($this->a == "\n")
- throw new RuntimeException('Stray regex pattern. ' . $this->index);
- echo $this->a;
- }
- $this->b = $this->getReal();
- }
- /**
- * Resets attributes that do not need to be stored between requests so that the next request is ready to go.
- */
- protected function clean()
- {
- unset($this->input);
- $this->index = 0;
- $this->a = $this->b = '';
- unset($this->c);
- unset($this->options);
- }
- /**
- * Checks to see if a character is alphanumeric.
- *
- * @return bool
- */
- static protected function isAlphaNumeric($char)
- {
- return preg_match('/^[\w\$]$/', $char) === 1 || $char == '/';
- }
- }