gistfile1.js

(function (exports) {
  var shortCodeRegex = /\{\{\s*(.+?)\}\}/g,
    hasWhitespaceRegex = /\s+/;

  /**
   * @param {string} input - Parsed string
   * @param {object} [context] - context object defining shortcodes
   * @param {object} [callContext] - call context for any functions called within any shortcode replacement
   *
   * Supported Inputs:
   *    {{Count_ForSale_Total}}
   *    {{Count_ForSale_Total test="argument"}}
   *    {{Test_Func test="argument" nice="dude" }}
   *
   * Not Supported Inputs:
   *    {{Count_ForSale_Total test=arguments}}
   */
  exports.replace = function doShortCodeReplace(input, context, callContext) {
    callContext = callContext || this;

    return input.replace(shortCodeRegex, function (wholeMatch, shortCode, index) {
      var result,
        typeofResult,
        codeArguments,
        codeKey,
        tmpCodeArguments,
        matchedCodeArguments,
        argumentsRegex,
        hasWhitespace;

      hasWhitespace = hasWhitespaceRegex.test(shortCode);

      // test for no whitespace before checking context hash
      if (!hasWhitespace) {

        // grab value from keyed hash
        result = context[shortCode];
        typeofResult = typeof result;

        // check if valid
        if (typeofResult === 'undefined') {

          return '{{! Invalid Shortcode : "' + shortCode + '" }}';
        }

        // short-circuit processing, no need to continue if not a function
        if (typeofResult !== 'function') {

          return result;
        }
      } else {

        // if whitespace exists, start processing for arguments
        result = shortCode;
      }

      // check if has arguments
      if (hasWhitespace) {

        argumentsRegex = /(\S+)=["']?((?:.(?!["']?\s+(?:\S+)=|[$"']))+.)["']?/g;

        result = result.split(' ');
        codeKey = result.shift();
        tmpCodeArguments = result.join(' ');

        // grab value from keyed hash
        result = context[codeKey];
        typeofResult = typeof result;

        if (typeofResult !== 'function') {

          return result;
        }

        codeArguments = {};

        while ((matchedCodeArguments = argumentsRegex.exec(tmpCodeArguments)) != null) {

          codeArguments[matchedCodeArguments[1]] = matchedCodeArguments[2];
        }

        if (Object.keys(codeArguments).length < 1) {

          return '{{! Invalid Shortcode : "' + shortCode + '" : Invalid arguments format given (no matches) }}';
        }

        return safeFunctionCall(result, callContext, codeArguments);
      }

      return result;
    });
  }

  /**
    Pass through function to safely call function and not disqualifying from compilation
  **/
  function safeFunctionCall(func, context, options) {
    try {
      return func.call(context, options);
    } catch (err) {
      var _toString = err.toString;
      err.toString = function () {
        return '{{! ' + _toString.call(err) + ' }}';
      }
      return err;
    }
  }

})(exports);


/***** EXAMPLE *****/
var context = {
    Count_ForSale_Total: 123456,
    Count_ForRent_Total: 9876,
    Test_Func: function (options) {
      return 'Test Function: ' + JSON.stringify(options);
    }
  };

console.log(exports.replace('{{  Count_ForSale_Total}} For Sale Homes and {{Test_Func test="dude" neat="oh" sweet="man"  }} For Rent Homes', context));