refactor: merge backlinks and backtranscludes indexer

core/modules/indexers/back-indexer.js

@@ -0,0 +1,119 @@
+/*\
+title: $:/core/modules/indexers/back-indexer.js
+type: application/javascript
+module-type: indexer
+
+By parsing the tiddler text, indexes the tiddlers' back links, back transclusions, block level back links.
+
+\*/
+function BackIndexer(wiki) {
+	this.wiki = wiki;
+}
+
+BackIndexer.prototype.init = function() {
+	this.subIndexers = {
+		link: new BackSubIndexer(this,"extractLinks"),
+		transclude: new BackSubIndexer(this,"extractTranscludes"),
+	};
+};
+
+BackIndexer.prototype.rebuild = function() {
+	$tw.utils.each(this.subIndexers,function(subIndexer) {
+		subIndexer.rebuild();
+	});
+};
+
+BackIndexer.prototype.update = function(updateDescriptor) {
+	$tw.utils.each(this.subIndexers,function(subIndexer) {
+		subIndexer.update(updateDescriptor);
+	});
+};
+function BackSubIndexer(indexer,extractor) {
+	this.wiki = indexer.wiki;
+	this.indexer = indexer;
+	this.extractor = extractor;
+	this.index = null; // Hashmap of tag title to {isSorted: bool, titles: [array]} or null if not yet initialised
+}
+
+BackSubIndexer.prototype.init = function() {
+	// lazy init until first lookup
+	this.index = null;
+}
+
+BackSubIndexer.prototype._init = function() {
+	/**
+	 * {
+	 *   [target title, e.g. tiddler title being linked to]:
+	 *     {
+	 * 		   [source title, e.g. tiddler title that has link syntax in its text]: true
+	 * 	   }
+	 * }
+	 */
+	this.index = Object.create(null);
+	var self = this;
+	this.wiki.forEachTiddler(function(sourceTitle,tiddler) {
+		var newTargets = self._getTarget(tiddler);
+		$tw.utils.each(newTargets, function(target) {
+			if(!self.index[target]) {
+				self.index[target] = Object.create(null);
+			}
+			self.index[target][sourceTitle] = true;
+		});
+	});
+}
+
+BackSubIndexer.prototype.rebuild = function() {
+	this.index = null;
+}
+
+/*
+* Get things that is being referenced in the text, e.g. tiddler names in the link syntax.
+*/
+BackSubIndexer.prototype._getTarget = function(tiddler) {
+	var parser = this.wiki.parseText(tiddler.fields.type, tiddler.fields.text, {});
+	if(parser) {
+		return this.wiki[this.extractor](parser.tree);
+	}
+	return [];
+}
+
+BackSubIndexer.prototype.update = function(updateDescriptor) {
+	// lazy init/update until first lookup
+	if(!this.index) {
+		return;
+	}
+	var newTargets = [],
+	    oldTargets = [],
+	    self = this;
+	if(updateDescriptor.old.exists) {
+		oldTargets = this._getTarget(updateDescriptor.old.tiddler);
+	}
+	if(updateDescriptor.new.exists) {
+		newTargets = this._getTarget(updateDescriptor.new.tiddler);
+	}
+
+	$tw.utils.each(oldTargets,function(target) {
+		if(self.index[target]) {
+			delete self.index[target][updateDescriptor.old.tiddler.fields.title];
+		}
+	});
+	$tw.utils.each(newTargets,function(target) {
+		if(!self.index[target]) {
+			self.index[target] = Object.create(null);
+		}
+		self.index[target][updateDescriptor.new.tiddler.fields.title] = true;
+	});
+}
+
+BackSubIndexer.prototype.lookup = function(title) {
+	if(!this.index) {
+		this._init();
+	}
+	if(this.index[title]) {
+		return Object.keys(this.index[title]);
+	} else {
+		return [];
+	}
+}
+
+exports.BackIndexer = BackIndexer;

core/modules/wiki.js

@@ -534,8 +534,8 @@ Return an array of tiddler titles that link to the specified tiddler
 */
 exports.getTiddlerBacklinks = function(targetTitle) {
 	var self = this,
-		backlinksIndexer = this.getIndexer("BacklinksIndexer"),
-		backlinks = backlinksIndexer && backlinksIndexer.lookup(targetTitle);
+		backIndexer = this.getIndexer("BackIndexer"),
+		backlinks = backIndexer && backIndexer.subIndexers.link.lookup(targetTitle);
 
 	if(!backlinks) {
 		backlinks = [];
@@ -596,17 +596,11 @@ Return an array of tiddler titles that transclude to the specified tiddler
 */
 exports.getTiddlerBacktranscludes = function(targetTitle) {
 	var self = this,
-		backtranscludesIndexer = this.getIndexer("BacktranscludesIndexer"),
-		backtranscludes = backtranscludesIndexer && backtranscludesIndexer.lookup(targetTitle);
+		backIndexer = this.getIndexer("BackIndexer"),
+		backtranscludes = backIndexer && backIndexer.subIndexers.transclude.lookup(targetTitle);
 
 	if(!backtranscludes) {
 		backtranscludes = [];
-		this.forEachTiddler(function(title,tiddler) {
-			var transcludes = self.getTiddlertranscludes(title);
-			if(transcludes.indexOf(targetTitle) !== -1) {
-				backtranscludes.push(title);
-			}
-		});
 	}
 	return backtranscludes;
 };

editions/tw5.com/tiddlers/filters/examples/backtransclude.tid

@@ -0,0 +1,5 @@
+tags: [[backtranscludes Operator]] [[Operator Examples]]
+title: backtranscludes Operator (Examples)
+type: text/vnd.tiddlywiki
+
+<<.operator-example 1 "[[Motovun Jack.jpg]backtranscludes[]]">>

editions/tw5.com/tiddlers/filters/examples/transclude.tid

@@ -0,0 +1,5 @@
+tags: [[transcludes Operator]] [[Operator Examples]]
+title: transcludes Operator (Examples)
+type: text/vnd.tiddlywiki
+
+<<.operator-example 1 "[[Images in WikiText]transcludes[]]">>