Equivalent for Parse.Query.count(), for now not backed by a store

Author: philikon

src/ParsePatches.js

@@ -61,6 +61,14 @@ var patches = {
     return this.equalTo('objectId', objectId).limit(1);
   },
 
+  /**
+   * The ParseReact equivalent to Parse.Query(...).count()
+   */
+  observeCount: function() {
+    this._observeCount = true;
+    return this;
+  },
+
   /**
    * Patches for Parse.User to watch for user signup / login / logout
    */
@@ -99,6 +107,9 @@ var ParsePatches = {
     if (!Parse.Query.prototype.observeOne) {
       Parse.Query.prototype.observeOne = patches.observeOne;
     }
+    if (!Parse.Query.prototype.observeCount) {
+      Parse.Query.prototype.observeCount = patches.observeCount;
+    }
     pointerMethods.forEach(function(method) {
       var old = Parse.Query.prototype[method];
       Parse.Query.prototype[method] = function(attr, value) {

src/Subscription.js

@@ -113,8 +113,10 @@ class Subscription {
     if (resultSet[0] && !(resultSet[0] instanceof Id)) {
       resultSet = resultSet.map(extractId);
     }
-    var data = resultSet.length ? ObjectStore.getDataForIds(resultSet) : [];
-    callbacks.onNext(this.originalQuery._observeOne ? data[0] : data);
+    if (!this.originalQuery._observeCount) {
+      var data = resultSet.length ? ObjectStore.getDataForIds(resultSet) : [];
+      callbacks.onNext(this.originalQuery._observeOne ? data[0] : data);
+    }
 
     return oid;
   }
@@ -140,6 +142,16 @@ class Subscription {
    */
   issueQuery() {
     this.pending = true;
+    if (this.originalQuery._observeCount) {
+      this.originalQuery.count().then((result) => {
+        this.pending = false;
+        this._forEachSubscriber((subscriber) => subscriber.onNext(result));
+      }, (err) => {
+        this.pending = false;
+        this.pushError(err);
+      });
+      return;
+    }
     this.originalQuery.find().then((results) => {
       this.pending = false;
       this.resultSet = ObjectStore.storeQueryResults(