build/js/Packer.js

   1 /*\r
   2         Packer version 3.0 (beta 5) - copyright 2004-2007, Dean Edwards\r
   3         http://www.opensource.org/licenses/mit-license\r
   4 */\r
   5 \r
   6 eval(base2.namespace);\r
   7 \r
   8 var IGNORE = RegGrp.IGNORE;\r
   9 var REMOVE = "";\r
  10 var SPACE = " ";\r
  11 var WORDS = /\w+/g;\r
  12 \r
  13 var Packer = Base.extend({\r
  14         minify: function(script) {\r
  15                 script = script.replace(Packer.CONTINUE, "");\r
  16                 script = Packer.clean.exec(script);\r
  17                 script = Packer.whitespace.exec(script);\r
  18                 script = Packer.clean.exec(script); // seem to grab a few more bytes on the second pass\r
  19                 return script;\r
  20         },\r
  21         \r
  22         pack: function(script, base62, shrink) {\r
  23                 script = this.minify(script);\r
  24                 if (shrink) script = this._shrinkVariables(script);\r
  25                 if (base62) script = this._base62Encode(script);        \r
  26                 return script;\r
  27         },\r
  28         \r
  29         _base62Encode: function(script) {\r
  30                 var words = new Words(script);\r
  31                 var encode = function(word) {\r
  32                         return words.fetch(word).encoded;\r
  33                 };\r
  34                 \r
  35                 /* build the packed script */\r
  36                 \r
  37                 var p = this._escape(script.replace(WORDS, encode));            \r
  38                 var a = Math.min(Math.max(words.count(), 2), 62);               \r
  39                 var c = words.count();          \r
  40                 var k = words;\r
  41                 var e = Packer["ENCODE" + (a > 10 ? a > 36 ? 62 : 36 : 10)];\r
  42                 var r = a > 10 ? "e(c)" : "c";\r
  43                 \r
  44                 // the whole thing\r
  45                 return format(Packer.UNPACK, p,a,c,k,e,r);\r
  46         },\r
  47         \r
  48         _escape: function(script) {\r
  49                 // single quotes wrap the final string so escape them\r
  50                 // also escape new lines required by conditional comments\r
  51                 return script.replace(/([\\'])/g, "\\$1").replace(/[\r\n]+/g, "\\n");\r
  52         },\r
  53         \r
  54         _shrinkVariables: function(script) {\r
  55                 // Windows Scripting Host cannot do regexp.test() on global regexps.\r
  56                 var global = function(regexp) {\r
  57                         // This function creates a global version of the passed regexp.\r
  58                         return new RegExp(regexp.source, "g");\r
  59                 };\r
  60                 \r
  61                 var data = []; // encoded strings and regular expressions\r
  62                 var store = function(string) {\r
  63                         var replacement = "#" + data.length;\r
  64                         data.push(string);\r
  65                         return replacement;\r
  66                 };\r
  67                 \r
  68                 // Base52 encoding (a-Z)\r
  69                 var encode52 = function(c) {\r
  70                         return (c < 52 ? '' : arguments.callee(parseInt(c / 52))) +\r
  71                                 ((c = c % 52) > 25 ? String.fromCharCode(c + 39) : String.fromCharCode(c + 97));\r
  72                 };\r
  73                                 \r
  74                 // identify blocks, particularly identify function blocks (which define scope)\r
  75                 var BLOCK = /(function\s*[\w$]*\s*\(\s*([^\)]*)\s*\)\s*)?(\{([^{}]*)\})/;\r
  76                 var VAR_ = /var\s+/g;\r
  77                 var VAR_NAME = /var\s+[\w$]{2,}/g; // > 1 char\r
  78                 var COMMA = /\s*,\s*/;\r
  79                 var blocks = []; // store program blocks (anything between braces {})\r
  80                 // encoder for program blocks\r
  81                 var encode = function(block, func, args) {\r
  82                         if (func) { // the block is a function block\r
  83                         \r
  84                                 // decode the function block (THIS IS THE IMPORTANT BIT)\r
  85                                 // We are retrieving all sub-blocks and will re-parse them in light\r
  86                                 // of newly shrunk variables\r
  87                                 block = decode(block);\r
  88                                 \r
  89                                 // create the list of variable and argument names \r
  90                                 var vars = match(block, VAR_NAME).join(",").replace(VAR_, "");\r
  91                                 var ids = Array2.combine(args.split(COMMA).concat(vars.split(COMMA)));\r
  92                                 \r
  93                                 // process each identifier\r
  94                                 var count = 0, shortId;\r
  95                                 forEach (ids, function(id) {\r
  96                                         id = rescape(trim(id));\r
  97                                         if (id) {\r
  98                                                 // find the next free short name (check everything in the current scope)\r
  99                                                 do shortId = encode52(count++);\r
 100                                                 while (new RegExp("[^\\w$.]" + shortId + "[^\\w$:]").test(block));\r
 101                                                 // replace the long name with the short name\r
 102                                                 var reg = new RegExp("([^\\w$.])" + id + "([^\\w$:])");\r
 103                                                 while (reg.test(block)) block = block.replace(global(reg), "$1" + shortId + "$2");\r
 104                                                 var reg = new RegExp("([^{,])" + id + ":", "g");\r
 105                                                 block = block.replace(reg, "$1" + shortId + ":");\r
 106                                         }\r
 107                                 });\r
 108                         }\r
 109                         var replacement = "~" + blocks.length;\r
 110                         blocks.push(block);\r
 111                         return replacement;\r
 112                 };\r
 113                 \r
 114                 // decoder for program blocks\r
 115                 var ENCODED = /~(\d+)/;\r
 116                 var decode = function(script) {\r
 117                         while (ENCODED.test(script)) {\r
 118                                 script = script.replace(global(ENCODED), function(match, index) {\r
 119                                         return blocks[index];\r
 120                                 });\r
 121                         }\r
 122                         return script;\r
 123                 };\r
 124                 \r
 125                 // encode strings and regular expressions\r
 126                 script = Packer.data.exec(script, store);\r
 127                 \r
 128                 // remove closures (this is for base2 namespaces only)\r
 129                 script = script.replace(/new function\(_\)\s*\{/g, "{;#;");\r
 130                 \r
 131                 // encode blocks, as we encode we replace variable and argument names\r
 132                 while (BLOCK.test(script)) {\r
 133                         script = script.replace(global(BLOCK), encode);\r
 134                 }\r
 135                 \r
 136                 // put the blocks back\r
 137                 script = decode(script);\r
 138                 \r
 139                 // put back the closure (for base2 namespaces only)\r
 140                 script = script.replace(/\{;#;/g, "new function(_){");\r
 141                 \r
 142                 // put strings and regular expressions back\r
 143                 script = script.replace(/#(\d+)/g, function(match, index) {             \r
 144                         return data[index];\r
 145                 });\r
 146                 \r
 147                 return script;\r
 148         }\r
 149 }, {\r
 150         CONTINUE: /\\\r?\n/g,\r
 151         \r
 152         ENCODE10: "String",\r
 153         ENCODE36: "function(c){return c.toString(a)}",\r
 154         ENCODE62: "function(c){return(c<a?'':e(parseInt(c/a)))+((c=c%a)>35?String.fromCharCode(c+29):c.toString(36))}",\r
 155         \r
 156         UNPACK: "eval(function(p,a,c,k,e,r){e=%5;if(!''.replace(/^/,String)){while(c--)r[%6]=k[c]" +\r
 157                 "||%6;k=[function(e){return r[e]}];e=function(){return'\\\\w+'};c=1};while(c--)if(k[c])p=p." +\r
 158                         "replace(new RegExp('\\\\b'+e(c)+'\\\\b','g'),k[c]);return p}('%1',%2,%3,'%4'.split('|'),0,{}))",\r
 159         \r
 160         init: function() {\r
 161                 this.data = reduce(this.data, new RegGrp, function(data, replacement, expression) {\r
 162                         data.store(this.javascript.exec(expression), replacement);\r
 163                         return data;\r
 164                 }, this);\r
 165                 this.clean = this.data.union(this.clean);\r
 166                 this.whitespace = this.data.union(this.whitespace);\r
 167         },\r
 168         \r
 169         clean: {\r
 170                 ";;;[^\\n]*": REMOVE, // triple semi-colons treated like line comments\r
 171                 "\\(\\s*;\\s*;\\s*\\)": "(;;)", // for (;;) loops\r
 172                 "throw[^};]+[};]": IGNORE, // a safari 1.3 bug\r
 173                 ";+\\s*([};])": "$1"\r
 174         },\r
 175         \r
 176         data: {\r
 177                 // strings\r
 178                 "STRING1": IGNORE,\r
 179                 'STRING2': IGNORE,\r
 180                 "CONDITIONAL": IGNORE, // conditional comments\r
 181                 "(COMMENT1)\\n\\s*(REGEXP)?": "\n$2",\r
 182                 "(COMMENT2)\\s*(REGEXP)?": " $3",\r
 183                 "COMMENT1$": REMOVE,\r
 184                 "([\\[(\\^=,{}:;&|!*?])\\s*(REGEXP)": "$1$2"\r
 185         },\r
 186         \r
 187         javascript: new RegGrp({\r
 188                 COMMENT1:    /\/\/[^\n]*/.source,\r
 189                 COMMENT2:    /\/\*[^*]*\*+([^\/][^*]*\*+)*\//.source,\r
 190                 CONDITIONAL: /\/\*@|@\*\/|\/\/@[^\n]*\n/.source,\r
 191                 REGEXP:      /\/(\\\/|[^*\/])(\\.|[^\/\n\\])*\//.source,\r
 192                 STRING1:     /'(\\.|[^'\\])*'/.source,\r
 193                 STRING2:     /"(\\.|[^"\\])*"/.source\r
 194         }),\r
 195         \r
 196         whitespace: {\r
 197                 "(\\d)\\s+(\\.\\s*[a-z\\$_\\[(])": "$1 $2", // http://dean.edwards.name/weblog/2007/04/packer3/#comment84066\r
 198                 "([+-])\\s+([+-])": "$1 $2", // c = a++ +b;\r
 199                 "\\b\\s+\\$\\s+\\b": " $ ", // var $ in\r
 200                 "\\$\\s+\\b": "$ ", // object$ in\r
 201                 "\\b\\s+\\$": " $", // return $object\r
 202                 "\\b\\s+\\b": SPACE,\r
 203                 "\\s+": REMOVE\r
 204         }\r
 205 });\r