Add very basic tiddler filtering support

rabbithole/core/modules/wiki.filters.js

@@ -0,0 +1,74 @@
+/*\
+title: $:/core/modules/wiki.filters.js
+type: application/javascript
+module-type: wikimethod
+
+Filter method for the $tw.Wiki object
+
+\*/
+(function(){
+
+/*jslint node: true, browser: true */
+/*global $tw: false */
+"use strict";
+
+//# Extensible filter functions
+exports.filters = {
+	tiddler: function(results,match) {
+		var title = match[1] || match[4];
+		if(results.indexOf(title) === -1) {
+			results.push(title);
+		}
+	},
+	tag: function(results,match) {
+	},
+	sort: function(results,match) {
+	},
+	limit: function(results,match) {
+		return results.slice(0,parseInt(match[3],10));
+	},
+	field: function(results,match) {
+	},
+	is: function(results,match) {
+		switch(match[3]) {
+			case "pluginModule":
+				this.forEachTiddler(function(title,tiddler) {
+					if(title.indexOf("$:/plugins/") === 0 && tiddler.fields.type === "application/javascript") {
+						if(results.indexOf(title) === -1) {
+							results.push(title);
+						}
+					}
+				});
+				break;
+			case "pluginTiddler":
+				this.forEachTiddler(function(title,tiddler) {
+					if(title.indexOf("$:/plugins/") === 0 && tiddler.fields.type !== "application/javascript") {
+						if(results.indexOf(title) === -1) {
+							results.push(title);
+						}
+					}
+				});
+				break;
+		}
+	}
+};
+
+// Return the tiddler titles from the store that match a filter expression
+//    filter - filter expression (eg "tidlertitle [[multi word tiddler title]] [tag[systemConfig]]")
+// Returns an array of tiddler titles that match the filter expression
+exports.filterTiddlers = function(filter) {
+	// text or [foo[bar]] or [[tiddler title]]
+	var re = /([^\s\[\]]+)|(?:\[([ \w\.\-]+)\[([^\]]+)\]\])|(?:\[\[([^\]]+)\]\])/mg;
+	var results = [];
+	if(filter) {
+		var match = re.exec(filter);
+		while(match) {
+			var handler = (match[1]||match[4]) ? 'tiddler' : (this.filters[match[2]] ? match[2] : 'field');
+			this.filters[handler].call(this,results,match);
+			match = re.exec(filter);
+		}
+	}
+	return results;
+};
+
+})();