File: highlight/js/highlight-accentfold.js

            /**
            Adds accent-folding highlighters to `Y.Highlight`.
            
            @module highlight
            @submodule highlight-accentfold
            **/
            
            /**
            @class Highlight
            @static
            **/
            
            var AccentFold = Y.Text.AccentFold,
                Escape     = Y.Escape,
            
                EMPTY_OBJECT = {},
            
            Highlight = Y.mix(Y.Highlight, {
                // -- Public Static Methods ------------------------------------------------
            
                /**
                Accent-folding version of `all()`.
            
                @method allFold
                @param {String} haystack String to apply highlighting to.
                @param {String|String[]} needles String or array of strings that should be
                  highlighted.
                @param {Object} [options] Options object.
                @param {Boolean} [options.startsWith=false] If `true`, matches must be
                    anchored to the beginning of the string.
                @return {String} Escaped and highlighted copy of _haystack_.
                @static
                **/
                allFold: function (haystack, needles, options) {
                    var template = Highlight._TEMPLATE,
                        results  = [],
                        startPos = 0,
                        chunk, i, len, match, result;
            
                    options = Y.merge({
                        // This tells Highlight.all() not to escape HTML, in order to ensure
                        // usable match offsets. The output of all() is discarded, and we
                        // perform our own escaping before returning the highlighted string.
                        escapeHTML: false,
            
                        // While the highlight regex operates on the accent-folded strings,
                        // this replacer will highlight the matched positions in the
                        // original string.
                        //
                        // Note: this implementation doesn't handle multi-character folds,
                        // like "æ" -> "ae". Doing so correctly would be prohibitively
                        // expensive both in terms of code size and runtime performance, so
                        // I've chosen to take the pragmatic route and just not do it at
                        // all. This is one of many reasons why accent folding is best done
                        // on the server.
                        replacer: function (match, p1, foldedNeedle, pos) {
                            var len;
            
                            // Ignore matches inside HTML entities.
                            if (p1 && !(/\s/).test(foldedNeedle)) {
                                return match;
                            }
            
                            len = foldedNeedle.length;
            
                            results.push([
                                haystack.substring(startPos, pos), // substring between previous match and this match
                                haystack.substr(pos, len)          // match to be highlighted
                            ]);
            
                            startPos = pos + len;
                        }
                    }, options || EMPTY_OBJECT);
            
                    // Run the highlighter on the folded strings. We don't care about the
                    // output; our replacer function will build the canonical highlighted
                    // string, with original accented characters.
                    Highlight.all(AccentFold.fold(haystack), AccentFold.fold(needles), options);
            
                    // Tack on the remainder of the haystack that wasn't highlighted, if
                    // any.
                    if (startPos < haystack.length) {
                        results.push([haystack.substr(startPos)]);
                    }
            
                    // Highlight and escape the string.
                    for (i = 0, len = results.length; i < len; ++i) {
                        chunk = Escape.html(results[i][0]);
            
                        if ((match = results[i][1])) {
                            chunk += template.replace(/\{s\}/g, Escape.html(match));
                        }
            
                        results[i] = chunk;
                    }
            
                    return results.join('');
                },
            
                /**
                Accent-folding version of `start()`.
            
                @method startFold
                @param {String} haystack String to apply highlighting to.
                @param {String|String[]} needles String or array of strings that should be
                  highlighted.
                @return {String} Escaped and highlighted copy of _haystack_.
                @static
                **/
                startFold: function (haystack, needles) {
                    return Highlight.allFold(haystack, needles, {startsWith: true});
                },
            
                /**
                Accent-folding version of `words()`.
            
                @method wordsFold
                @param {String} haystack String to apply highlighting to.
                @param {String|String[]} needles String or array of strings containing words
                  that should be highlighted. If a string is passed, it will be split
                  into words; if an array is passed, it is assumed to have already been
                  split.
                @return {String} Escaped and highlighted copy of _haystack_.
                @static
                **/
                wordsFold: function (haystack, needles) {
                    var template = Highlight._TEMPLATE;
            
                    return Highlight.words(haystack, AccentFold.fold(needles), {
                        mapper: function (word, needles) {
                            if (needles.hasOwnProperty(AccentFold.fold(word))) {
                                return template.replace(/\{s\}/g, Escape.html(word));
                            }
            
                            return Escape.html(word);
                        }
                    });
                }
            });