String replace helper for Dustjs

dust-replace-helper.js

(function (dust) {

    /**
     * Polyfill to create String.trim() if it's not natively available
     */
    if (!String.prototype.trim) {
        (function(){
            // Make sure we trim BOM and NBSP
            var rtrim = /^[\s\uFEFF\xA0]+|[\s\uFEFF\xA0]+$/g;
            String.prototype.trim = function () {
                return this.replace(rtrim, "");
            }
        })();
    }

    /**
     * Processes the given string to escape special meta characters used within
     * Regular Expressions. This is used by the replace helper.
     */
    function escapeRegExp(string) {
        return string.replace(/([.*+?^=!:${}()|\[\]\/\\])/g, "\\$1");
    }

    /**
     * Performs a global search and replace within a string.
     * In the following example, we replace all periods in the
     * message string with dashes and we trim the result.
     *
     * {@replace str="{message}" search="." replace="-" trim="true" /}
     *
     * str - the input string within which the search and replace will be performed
     * search - the character or sequence to search
     * replace - the character or sequence used to replace
     * trim - when 'true', will trim the string before returning result.
     *
     */
    dust.helpers.replace = function (chunk, ctx, bodies, params) {

        var str = dust.helpers.tap(params.str, chunk, ctx);
        var search = dust.helpers.tap(params.search, chunk, ctx);
        var replace = dust.helpers.tap(params.replace, chunk, ctx);
        var trim = dust.helpers.tap(params.trim, chunk, ctx);

        if(trim && trim == 'true') {
            str = str.trim();
        }

        var result = str.replace(new RegExp(escapeRegExp(search), 'g'), replace);

        return chunk.write( result );

    }

})(typeof exports !== 'undefined' ? module.exports = require('dustjs-linkedin') : dust);