Refs perf enhancement

lib/Model/ref.js

@@ -48,11 +48,13 @@ function addIndexListeners(model) {
     onIndexChange(segments, patchMove);
   });
   function onIndexChange(segments, patch) {
-    var fromMap = model._refs.fromMap;
-    for (var from in fromMap) {
-      var ref = fromMap[from];
+    var toPathMap = model._refs.toPathMap;
+    var refs = toPathMap.get(segments) || [];
+
+    for(var i = 0, len = refs.length; i < len; i++) {
+      var ref = refs[i];
+      var from = ref.from;
       if (!(ref.updateIndices &&
-        util.contains(segments, ref.toSegments) &&
         ref.toSegments.length > segments.length)) continue;
       var index = +ref.toSegments[segments.length];
       var patched = patch(index);
@@ -111,15 +113,15 @@ function addListener(model, type, fn) {
     // Find cases where an event is emitted on a path where a reference
     // is pointing. All original mutations happen on the fully dereferenced
     // location, so this detection only needs to happen in one direction
-    var toMap = model._refs.toMap;
+    var toPathMap = model._refs.toPathMap;
     var subpath;
     for (var i = 0, len = segments.length; i < len; i++) {
       subpath = (subpath) ? subpath + '.' + segments[i] : segments[i];
       // If a ref is found pointing to a matching subpath, re-emit on the
       // place where the reference is coming from as if the mutation also
       // occured at that path
-      var refs = toMap[subpath];
-      if (!refs) continue;
+      var refs = toPathMap.get(subpath.split('.'), true);
+      if (!refs.length) continue;
       var remaining = segments.slice(i + 1);
       for (var refIndex = 0, numRefs = refs.length; refIndex < numRefs; refIndex++) {
         var ref = refs[refIndex];
@@ -138,9 +140,9 @@ function addListener(model, type, fn) {
     }
     // If a ref points to a child of a matching subpath, get the value in
     // case it has changed and set if different
-    var parentToMap = model._refs.parentToMap;
-    var refs = parentToMap[subpath];
-    if (!refs) return;
+    var parentToPathMap = model._refs.parentToPathMap;
+    var refs = parentToPathMap.get(subpath.split('.'), true);
+    if (!refs.length) return;
     for (var refIndex = 0, numRefs = refs.length; refIndex < numRefs; refIndex++) {
       var ref = refs[refIndex];
       var value = model._get(ref.toSegments);
@@ -208,9 +210,16 @@ Model.prototype.removeAllRefs = function(subpath) {
   this._removeAllRefs(segments);
 };
 Model.prototype._removeAllRefs = function(segments) {
-  this._removeMapRefs(segments, this.root._refs.fromMap);
+  this._removePathMapRefs(segments, this.root._refs.fromPathMap);
   this._removeMapRefs(segments, this.root._refLists.fromMap);
 };
+Model.prototype._removePathMapRefs = function(segments, map) {
+  var refs = map.getList(segments);
+  for(var i = 0, len = refs.length; i < len; i++) {
+    var ref = refs[i];
+    this._removeRef(ref.fromSegments, ref.from);
+  }
+};
 Model.prototype._removeMapRefs = function(segments, map) {
   for (var from in map) {
     var fromSegments = map[from].fromSegments;
@@ -227,7 +236,7 @@ Model.prototype.dereference = function(subpath) {
 
 Model.prototype._dereference = function(segments, forArrayMutator, ignore) {
   if (segments.length === 0) return segments;
-  var refs = this.root._refs.fromMap;
+  var refs = this.root._refs.fromPathMap;
   var refLists = this.root._refLists.fromMap;
   var doAgain;
   do {
@@ -236,7 +245,7 @@ Model.prototype._dereference = function(segments, forArrayMutator, ignore) {
     for (var i = 0, len = segments.length; i < len; i++) {
       subpath = (subpath) ? subpath + '.' + segments[i] : segments[i];
 
-      var ref = refs[subpath];
+      var ref = refs.get(subpath.split('.'));
       if (ref) {
         var remaining = segments.slice(i + 1);
         segments = ref.toSegments.concat(remaining);
@@ -278,53 +287,214 @@ function Ref(model, from, to, options) {
   }
   this.updateIndices = options && options.updateIndices;
 }
-function FromMap() {}
-function ToMap() {}
 
 function Refs() {
-  this.fromMap = new FromMap();
-  this.toMap = new ToMap();
-  this.parentToMap = new ToMap();
+  this.parentToPathMap = new PathListMap();
+  this.toPathMap = new PathListMap();
+  this.fromPathMap = new PathMap();
 }
 
 Refs.prototype.add = function(ref) {
-  this.fromMap[ref.from] = ref;
-  listMapAdd(this.toMap, ref.to, ref);
+  this.fromPathMap.add(ref.fromSegments, ref);
+  this.toPathMap.add(ref.toSegments, ref);
   for (var i = 0, len = ref.parentTos.length; i < len; i++) {
-    listMapAdd(this.parentToMap, ref.parentTos[i], ref);
+    this.parentToPathMap.add(ref.parentTos[i].split('.'), ref);
   }
 };
 
 Refs.prototype.remove = function(from) {
-  var ref = this.fromMap[from];
+  var ref = this.fromPathMap.get((from || '').split('.'));
   if (!ref) return;
-  delete this.fromMap[from];
-  listMapRemove(this.toMap, ref.to, ref);
+  this.fromPathMap.delete(ref.fromSegments);
+  this.toPathMap.delete(ref.toSegments, ref);
   for (var i = 0, len = ref.parentTos.length; i < len; i++) {
-    listMapRemove(this.parentToMap, ref.parentTos[i], ref);
+    this.parentToPathMap.delete(ref.parentTos[i].split('.'), ref);
   }
   return ref;
 };
 
 Refs.prototype.toJSON = function() {
   var out = [];
-  for (var from in this.fromMap) {
-    var ref = this.fromMap[from];
+  var refs = this.fromPathMap.getList([]);
+
+  for(var i = 0, len = refs.length; i < len; i++) {
+    var ref = refs[i];
     out.push([ref.from, ref.to]);
   }
   return out;
 };
 
-function listMapAdd(map, name, item) {
-  map[name] || (map[name] = []);
-  map[name].push(item);
+function PathMap() {
+  this.map = {};
+}
+
+PathMap.prototype.add = function (segments, item) {
+  var map = this.map;
+
+  for(var i = 0, len = segments.length - 1; i < len; i++) {
+    map[segments[i]] = map[segments[i]] || {};
+    map = map[segments[i]];
+  }
+
+  map[segments[segments.length - 1]] = {"$item": item};
+};
+
+PathMap.prototype.get = function (segments) {
+  var val = this._get(segments);
+
+  return (val && val['$item']) ? val['$item'] : void 0;
+};
+
+PathMap.prototype._get = function (segments) {
+  var val = this.map;
+
+  for(var i = 0, len = segments.length; i < len; i++) {
+    val = val[segments[i]];
+    if(!val) return;
+  }
+
+  return val;
+};
+
+PathMap.prototype.getList = function (segments) {
+  var obj = this._get(segments);
+
+  return flattenObj(obj);
+};
+
+function flattenObj(obj) {
+  if(!obj) return [];
+
+  var arr = [];
+  var keys = Object.keys(obj);
+  if(obj['$item']) arr.push(obj['$item']);
+
+  for(var i = 0, len = keys.length; i < len; i++) {
+    if(keys[i] === '$item') continue;
+
+    arr = arr.concat(flattenObj(obj[keys[i]]));
+  }
+
+  return arr;
+};
+
+PathMap.prototype.delete = function (segments) {
+  del(this.map, segments.slice(0), true);
+};
+
+function del(map, segments, safe) {
+  var segment = segments.shift();
+
+  if(!segments.length) {
+    if(safe) {
+      delete map[segment];
+      return false;
+    } else {
+      return true;
+    }
+  }
+
+  var nextMap = map[segment];
+  if(!nextMap) return true;
+
+  var nextSafe = (Object.keys(nextMap).length > 1);
+  var remove = del(nextMap, segments, nextSafe);
+
+  if(remove) {
+    if(safe) {
+      delete map[segment];
+      return false;
+    } else {
+      return true;
+    }
+  }
+}
+
+function PathListMap() {
+  this.map = {};
+}
+
+PathListMap.prototype.add = function (segments, item) {
+  var map = this.map;
+
+  for(var i = 0, len = segments.length - 1; i < len; i++) {
+    map[segments[i]] = map[segments[i]] || {"$items": []};
+    map = map[segments[i]];
+  }
+
+  var segment = segments[segments.length - 1];
+
+  map[segment] = map[segment] || {"$items": []};
+  map[segment]['$items'].push(item);
+};
+
+PathListMap.prototype.get = function (segments, onlyAtLevel) {
+  var val = this.map;
+
+  for(var i = 0, len = segments.length; i < len; i++) {
+    val = val[segments[i]];
+    if(!val) return [];
+  }
+
+  if(onlyAtLevel) return (val['$items'] || []);
+
+  return flatten(val);
+};
+
+function flatten(obj) {
+  var arr = obj['$items'] || [];
+  var keys = Object.keys(obj);
+
+  for(var i = 0, len = keys.length; i < len; i++) {
+    if(keys[i] === '$items') continue;
+
+    arr.concat(flatten(obj[i]));
+  }
+
+  return arr;
 }
 
-function listMapRemove(map, name, item) {
-  var items = map[name];
-  if (!items) return;
-  var index = items.indexOf(item);
-  if (index === -1) return;
-  items.splice(index, 1);
-  if (!items.length) delete map[name];
+PathListMap.prototype.delete = function (segments, item) {
+  delList(this.map, segments.slice(0), item, true);
+};
+
+function delList(map, segments, item, safe) {
+  var segment = segments.shift();
+
+  if(!segments.length) {
+    if(!map[segment] || !map[segment]['$items']) return true;
+
+    var items = map[segment]['$items'];
+    var keys = Object.keys(map[segment]);
+
+    if(items.length < 2 && keys.length < 2) {
+      if(safe) {
+        delete map[segment];
+        return false;
+      } else {
+        return true;
+      }
+    } else {
+      var i = items.indexOf(item);
+
+      if(i > -1) items.splice(i, 1);
+
+      return false;
+    }
+  }
+
+  var nextMap = map[segment];
+  if(!nextMap) return true;
+
+  var nextSafe = (Object.keys(nextMap).length > 2 || nextMap['$items'].length);
+  var remove = delList(nextMap, segments, item, nextSafe);
+
+  if(remove) {
+    if(safe) {
+      delete map[segment];
+      return false;
+    } else {
+      return true;
+    }
+  }
 }