Re-use objects created by getData(): 50% speedup in expression evalua…

…tion

src/collection.js

@@ -68,22 +68,29 @@ var _ = Mavo.Collection = $.Class({
 		var env = {
 			context: this,
 			options: o,
-			data: []
+			data: this.liveData
 		};
 
-		this.children.forEach(item => {
+		if (env.options.live) {
+			this.proxyCache = {};
+		}
+
+		for (var i = 0, j = 0; item = this.children[i]; i++) {
 			if (!item.deleted || env.options.live) {
 				var itemData = item.getData(env.options);
 
 				if (env.options.live || Mavo.value(itemData) !== null) {
-					env.data.push(itemData);
+					env.data[j] = itemData;
+					j++;
 				}
 			}
-		});
+		}
+
+		env.data.length = j;
 
 		if (!this.mutable) {
 			// If immutable, drop nulls
-			env.data = env.data.filter(item => Mavo.value(item) !== null);
+			Mavo.filter(env.data, item => Mavo.value(item) !== null);
 
 			if (env.options.live && env.data.length === 1) {
 				// If immutable with only 1 item, return the item
@@ -96,18 +103,13 @@ var _ = Mavo.Collection = $.Class({
 			}
 		}
 
-		if (env.options.live && Array.isArray(env.data)) {
-			env.data[Mavo.toNode] = this;
-			env.data = this.relativizeData(env.data);
-		}
-
 		if (!env.options.live) {
 			env.data = Mavo.subset(this.data, this.inPath, env.data);
 		}
 
 		Mavo.hooks.run("node-getdata-end", env);
 
-		return env.data;
+		return (env.options.live? env.data[Mavo.toProxy] : env.data) || env.data;
 	},
 
 	// Create item but don't insert it anywhere
@@ -437,6 +439,8 @@ var _ = Mavo.Collection = $.Class({
 				}
 			}
 		}
+
+		this.createLiveData(data|| []);
 	},
 
 	find: function(property, o = {}) {
@@ -619,6 +623,10 @@ var _ = Mavo.Collection = $.Class({
 			});
 
 			return button;
+		},
+
+		liveData: function() {
+			return this.createLiveData([]);
 		}
 	},
 

src/group.js

@@ -44,6 +44,8 @@ var _ = Mavo.Group = $.Class({
 			}
 		});
 
+		this.childrenNames = Object.keys(this.children);
+
 		var vocabElement = (this.isRoot? this.element.closest("[vocab]") : null) || this.element;
 		this.vocab = vocabElement.getAttribute("vocab");
 
@@ -72,11 +74,9 @@ var _ = Mavo.Group = $.Class({
 			return env.data;
 		}
 
-		env.data = (this.data? Mavo.clone(Mavo.subset(this.data, this.inPath)) : {}) || {};
-
-		var properties = Object.keys(this.children);
+		env.data = this.liveData;
 
-		if (properties.length == 1 && properties[0] == this.property) {
+		if (this.childrenNames.length == 1 && this.childrenNames[0] == this.property) {
 			// {foo: {foo: 5}} should become {foo: 5}
 			var options = $.extend($.extend({}, env.options), {forceObjects: true});
 			env.data = this.children[this.property].getData(options);
@@ -87,22 +87,25 @@ var _ = Mavo.Group = $.Class({
 
 				if (obj.saved || env.options.live) {
 					var data = obj.getData(env.options);
+				}
 
-					if (data === null && !env.options.live) {
-						delete env.data[obj.property];
-					}
-					else {
-						env.data[obj.property] = data;
-					}
+				if (env.options.live || obj.saved && Mavo.value(data) !== null) {
+					env.data[obj.property] = data;
+				}
+				else {
+					delete env.data[obj.property];
 				}
 			}
 		}
 
-		if (!env.options.live) { // Stored data again
+		if (env.options.live) {
+			this.proxyCache = {};
+		}
+		else { // Stored data again
 			// If storing, use the rendered data too
 			env.data = Mavo.subset(this.data, this.inPath, env.data);
 
-			if (!properties.length && !this.isRoot) {
+			if (!this.childrenNames.length && !this.isRoot) {
 				// Avoid {} in the data
 				env.data = null;
 			}
@@ -117,14 +120,10 @@ var _ = Mavo.Group = $.Class({
 				}
 			}
 		}
-		else if (env.data) {
-			env.data[Mavo.toNode] = this;
-			env.data = this.relativizeData(env.data);
-		}
 
 		Mavo.hooks.run("node-getdata-end", env);
 
-		return env.data;
+		return (env.options.live? env.data[Mavo.toProxy] : env.data) || env.data;
 	},
 
 	/**
@@ -251,6 +250,14 @@ var _ = Mavo.Group = $.Class({
 				}
 			}
 		}
+
+		this.createLiveData(data);
+	},
+
+	lazy: {
+		liveData: function() {
+			return this.createLiveData();
+		}
 	},
 
 	static: {

src/mavo.js

@@ -683,7 +683,8 @@ var _ = self.Mavo = $.Class({
 
 		lazy: {
 			locale: () => document.documentElement.lang || "en-GB",
-			toNode: () => Symbol("toNode")
+			toNode: () => Symbol("toNode"),
+			toProxy: () => Symbol("toProxy")
 		}
 	}
 });

src/node.js

@@ -363,22 +363,20 @@ var _ = Mavo.Node = $.Class({
 	},
 
 	relativizeData: self.Proxy? function(data, options = {live: true}) {
-		var cache = {};
-
 		return new Proxy(data, {
 			get: (data, property, proxy) => {
 				if (property in data) {
 					return data[property];
 				}
 
 				// Checking if property is in proxy might add it to the cache
-				if (property in proxy && property in cache) {
-					return cache[property];
+				if (property in proxy && property in this.proxyCache) {
+					return this.proxyCache[property];
 				}
 			},
 
 			has: (data, property) => {
-				if (property in data || property in cache) {
+				if (property in data || property in this.proxyCache) {
 					return true;
 				}
 
@@ -387,16 +385,16 @@ var _ = Mavo.Node = $.Class({
 				// Special values
 				switch (property) {
 					case "$index":
-						cache[property] = this.index || 0;
+						this.proxyCache[property] = this.index || 0;
 						return true; // if index is 0 it's falsy and has would return false!
 					case "$next":
 					case "$previous":
 						if (this.closestCollection) {
-							cache[property] = this.closestCollection.getData(options)[this.index + (property == "$next"? 1 : -1)];
+							this.proxyCache[property] = this.closestCollection.getData(options)[this.index + (property == "$next"? 1 : -1)];
 							return true;
 						}
 
-						cache[property] = null;
+						this.proxyCache[property] = null;
 						return false;
 				}
 
@@ -412,14 +410,14 @@ var _ = Mavo.Node = $.Class({
 						ret = ret.getData(options);
 					}
 
-					cache[property] = ret;
+					this.proxyCache[property] = ret;
 
 					return true;
 				}
 
 				// Does it reference another Mavo?
-				if (property in Mavo.all && Mavo.all[property].root) {
-					return cache[property] = Mavo.all[property].root.getData(options);
+				if (property in Mavo.all && isNaN(property) && Mavo.all[property].root) {
+					return this.proxyCache[property] = Mavo.all[property].root.getData(options);
 				}
 
 				return false;
@@ -432,6 +430,13 @@ var _ = Mavo.Node = $.Class({
 		});
 	} : data => data,
 
+	createLiveData: function(obj = {}) {
+		this.liveData = obj;
+		this.liveData[Mavo.toNode] = this;
+		this.liveData[Mavo.toProxy] = this.relativizeData(this.liveData);
+		return this.liveData;
+	},
+
 	pathFrom: function(node) {
 		var path = this.path;
 		var nodePath = node.path;
@@ -537,6 +542,10 @@ var _ = Mavo.Node = $.Class({
 			}
 
 			return ret;
+		},
+
+		proxyCache: function() {
+			return {};
 		}
 	},
 

src/primitive.js

@@ -219,12 +219,19 @@ var _ = Mavo.Primitive = $.Class({
 					[Mavo.toNode]: this
 				});
 
+				env.data[Mavo.toProxy] = this.relativizeData(env.data);
+
 				if (this.collection) {
 					// Turn primitive collection items into objects, so we can have $index etc, and their property
 					// name etc resolve relative to them, not their parent group
 					env.data[this.property] = env.data;
-					env.data = this.relativizeData(env.data);
 				}
+
+				Mavo.hooks.run("node-getdata-end", env);
+
+				this.proxyCache = {};
+
+				return env.data[Mavo.toProxy];
 			}
 		}
 		else if (this.inPath.length) {

src/util.js

@@ -106,6 +106,8 @@ var _ = $.extend(Mavo, {
 		return arr === undefined? [] : Array.isArray(arr)? arr : [arr];
 	},
 
+	// Delete an element from an array
+	// @param all {Boolean} Delete more than one?
 	delete: (arr, element, all) => {
 		do {
 			var index = arr && arr.indexOf(element);
@@ -136,6 +138,17 @@ var _ = $.extend(Mavo, {
 		return new Set([...(set1 || []), ...(set2 || [])]);
 	},
 
+	// Filter an array in place
+	// TODO add index to callback
+	filter: (arr, callback) => {
+		for (var i=0; i<arr.length; i++) {
+			if (!callback(arr[i])) {
+				arr.splice(i, 1);
+				i--;
+			}
+		}
+	},
+
 	/**
 	 * DOM element utilities
 	 */