gitweb/static/js/lib/common-lib.js

   1 // Copyright (C) 2007, Fredrik Kuivinen <frekui@gmail.com>
   2 //               2007, Petr Baudis <pasky@suse.cz>
   3 //          2008-2011, Jakub Narebski <jnareb@gmail.com>
   4
   5 /**
   6  * @fileOverview Generic JavaScript code (helper functions)
   7  * @license GPLv2 or later
   8  */
   9
  10
  11 /* ============================================================ */
  12 /* ............................................................ */
  13 /* Padding */
  14
  15 /**
  16  * pad INPUT on the left with STR that is assumed to have visible
  17  * width of single character (for example nonbreakable spaces),
  18  * to WIDTH characters
  19  *
  20  * example: padLeftStr(12, 3, '\u00A0') == '\u00A012'
  21  *          ('\u00A0' is nonbreakable space)
  22  *
  23  * @param {Number|String} input: number to pad
  24  * @param {Number} width: visible width of output
  25  * @param {String} str: string to prefix to string, defaults to '\u00A0'
  26  * @returns {String} INPUT prefixed with STR x (WIDTH - INPUT.length)
  27  */
  28 function padLeftStr(input, width, str) {
  29         var prefix = '';
  30         if (typeof str === 'undefined') {
  31                 ch = '\u00A0'; // using '&nbsp;' doesn't work in all browsers
  32         }
  33
  34         width -= input.toString().length;
  35         while (width > 0) {
  36                 prefix += str;
  37                 width--;
  38         }
  39         return prefix + input;
  40 }
  41
  42 /**
  43  * Pad INPUT on the left to WIDTH, using given padding character CH,
  44  * for example padLeft('a', 3, '_') is '__a'
  45  *             padLeft(4, 2) is '04' (same as padLeft(4, 2, '0'))
  46  *
  47  * @param {String} input: input value converted to string.
  48  * @param {Number} width: desired length of output.
  49  * @param {String} ch: single character to prefix to string, defaults to '0'.
  50  *
  51  * @returns {String} Modified string, at least SIZE length.
  52  */
  53 function padLeft(input, width, ch) {
  54         var s = input + "";
  55         if (typeof ch === 'undefined') {
  56                 ch = '0';
  57         }
  58
  59         while (s.length < width) {
  60                 s = ch + s;
  61         }
  62         return s;
  63 }
  64
  65
  66 /* ............................................................ */
  67 /* Handling browser incompatibilities */
  68
  69 /**
  70  * Create XMLHttpRequest object in cross-browser way
  71  * @returns XMLHttpRequest object, or null
  72  */
  73 function createRequestObject() {
  74         try {
  75                 return new XMLHttpRequest();
  76         } catch (e) {}
  77         try {
  78                 return window.createRequest();
  79         } catch (e) {}
  80         try {
  81                 return new ActiveXObject("Msxml2.XMLHTTP");
  82         } catch (e) {}
  83         try {
  84                 return new ActiveXObject("Microsoft.XMLHTTP");
  85         } catch (e) {}
  86
  87         return null;
  88 }
  89
  90
  91 /**
  92  * Insert rule giving specified STYLE to given SELECTOR at the end of
  93  * first CSS stylesheet.
  94  *
  95  * @param {String} selector: CSS selector, e.g. '.class'
  96  * @param {String} style: rule contents, e.g. 'background-color: red;'
  97  */
  98 function addCssRule(selector, style) {
  99         var stylesheet = document.styleSheets[0];
 100
 101         var theRules = [];
 102         if (stylesheet.cssRules) {     // W3C way
 103                 theRules = stylesheet.cssRules;
 104         } else if (stylesheet.rules) { // IE way
 105                 theRules = stylesheet.rules;
 106         }
 107
 108         if (stylesheet.insertRule) {    // W3C way
 109                 stylesheet.insertRule(selector + ' { ' + style + ' }', theRules.length);
 110         } else if (stylesheet.addRule) { // IE way
 111                 stylesheet.addRule(selector, style);
 112         }
 113 }
 114
 115
 116 /* ............................................................ */
 117 /* Support for legacy browsers */
 118
 119 /**
 120  * Provides getElementsByClassName method, if there is no native
 121  * implementation of this method.
 122  *
 123  * NOTE that there are limits and differences compared to native
 124  * getElementsByClassName as defined by e.g.:
 125  *   https://developer.mozilla.org/en/DOM/document.getElementsByClassName
 126  *   http://www.whatwg.org/specs/web-apps/current-work/multipage/dom.html#dom-getelementsbyclassname
 127  *   http://www.whatwg.org/specs/web-apps/current-work/multipage/dom.html#dom-document-getelementsbyclassname
 128  *
 129  * Namely, this implementation supports only single class name as
 130  * argument and not set of space-separated tokens representing classes,
 131  * it returns Array of nodes rather than live NodeList, and has
 132  * additional optional argument where you can limit search to given tags
 133  * (via getElementsByTagName).
 134  *
 135  * Based on
 136  *   http://code.google.com/p/getelementsbyclassname/
 137  *   http://www.dustindiaz.com/getelementsbyclass/
 138  *   http://stackoverflow.com/questions/1818865/do-we-have-getelementsbyclassname-in-javascript
 139  *
 140  * See also http://ejohn.org/blog/getelementsbyclassname-speed-comparison/
 141  *
 142  * @param {String} class: name of _single_ class to find
 143  * @param {String} [taghint] limit search to given tags
 144  * @returns {Node[]} array of matching elements
 145  */
 146 if (!('getElementsByClassName' in document)) {
 147         document.getElementsByClassName = function (classname, taghint) {
 148                 taghint = taghint || "*";
 149                 var elements = (taghint === "*" && document.all) ?
 150                                document.all :
 151                                document.getElementsByTagName(taghint);
 152                 var pattern = new RegExp("(^|\\s)" + classname + "(\\s|$)");
 153                 var matches= [];
 154                 for (var i = 0, j = 0, n = elements.length; i < n; i++) {
 155                         var el= elements[i];
 156                         if (el.className && pattern.test(el.className)) {
 157                                 // matches.push(el);
 158                                 matches[j] = el;
 159                                 j++;
 160                         }
 161                 }
 162                 return matches;
 163         };
 164 } // end if
 165
 166
 167 /* ............................................................ */
 168 /* unquoting/unescaping filenames */
 169
 170 /**#@+
 171  * @constant
 172  */
 173 var escCodeRe = /\\([^0-7]|[0-7]{1,3})/g;
 174 var octEscRe = /^[0-7]{1,3}$/;
 175 var maybeQuotedRe = /^\"(.*)\"$/;
 176 /**#@-*/
 177
 178 /**
 179  * unquote maybe C-quoted filename (as used by git, i.e. it is
 180  * in double quotes '"' if there is any escape character used)
 181  * e.g. 'aa' -> 'aa', '"a\ta"' -> 'a    a'
 182  *
 183  * @param {String} str: git-quoted string
 184  * @returns {String} Unquoted and unescaped string
 185  *
 186  * @globals escCodeRe, octEscRe, maybeQuotedRe
 187  */
 188 function unquote(str) {
 189         function unq(seq) {
 190                 var es = {
 191                         // character escape codes, aka escape sequences (from C)
 192                         // replacements are to some extent JavaScript specific
 193                         t: "\t",   // tab            (HT, TAB)
 194                         n: "\n",   // newline        (NL)
 195                         r: "\r",   // return         (CR)
 196                         f: "\f",   // form feed      (FF)
 197                         b: "\b",   // backspace      (BS)
 198                         a: "\x07", // alarm (bell)   (BEL)
 199                         e: "\x1B", // escape         (ESC)
 200                         v: "\v"    // vertical tab   (VT)
 201                 };
 202
 203                 if (seq.search(octEscRe) !== -1) {
 204                         // octal char sequence
 205                         return String.fromCharCode(parseInt(seq, 8));
 206                 } else if (seq in es) {
 207                         // C escape sequence, aka character escape code
 208                         return es[seq];
 209                 }
 210                 // quoted ordinary character
 211                 return seq;
 212         }
 213
 214         var match = str.match(maybeQuotedRe);
 215         if (match) {
 216                 str = match[1];
 217                 // perhaps str = eval('"'+str+'"'); would be enough?
 218                 str = str.replace(escCodeRe,
 219                         function (substr, p1, offset, s) { return unq(p1); });
 220         }
 221         return str;
 222 }
 223
 224 /* end of common-lib.js */