javascript/util.js

   1 // Copyright 2011 Google Inc. All Rights Reserved.
   2
   3 /**
   4  * @fileoverview Some basic, useful utility functions.
   5  */
   6
   7 /**
   8  * Pours the data in template string.
   9  * @param {Object} datObject The data object to be filled in template string.
  10  * @return {string} The new string created from template string and filled
  11  *     with the given data.
  12  */
  13 String.prototype.supplant = function(datObject) {
  14   return this.replace(/{([^{}]*)}/g,
  15     function(match, firstSubMatch) {
  16       var replace = datObject[firstSubMatch];
  17       return (typeof replace === 'string' || typeof replace === 'number') ?
  18           replace : match;
  19     });
  20 };
  21
  22 /**
  23  * Queries the DOM.
  24  * @param {string} selector Selector to execute.
  25  * @param {HTMLElement=} context HTMLElement to query (optional).
  26  * @return {Array.<HTMLElement>} Array of matched elements (non-live).
  27  */
  28 function $(selector, context) {
  29   if (!(context && context instanceof HTMLElement)) {
  30     context = document;
  31   }
  32   return Array.prototype.slice.call(context.querySelectorAll(selector));
  33 }
  34
  35 /**
  36  * Provides units for time, given in hours, as hours or days.
  37  * @param {number} time The time, in hours.
  38  * @return {Object} The time and units of time (pluralized and localized).
  39  */
  40 function getUnitsForTime(time) {
  41   var units = 'hour';
  42   if (time >= 24) {
  43     units = 'day';
  44     time = time / 24;
  45   }
  46   units = chrome.i18n.getMessage(units + (time === 1 ? '' : 's') + 'String');
  47   return {
  48     time: time,
  49     units: units
  50   };
  51 }