From be0c2a91ea77eaae086fe0d98fcdb6e5c503d71d Mon Sep 17 00:00:00 2001
From: Scott Kyle <scott@appden.com>
Date: Tue, 1 Dec 2015 14:05:33 -0800
Subject: [PATCH] Fix RPC client error after deleting objects

Specifically for objects with lists, since the mutation listener would fire on a list that no longer is attached. If during the mutation listener that error is thrown, then the listener will be removed and the error will not be propagated.
---
 lib/rpc.js              |  9 ++++++++-
 lib/util.js             | 22 ++++++++++++++++++++--
 tests/lib/ArrayTests.js | 13 +++++++++++--
 3 files changed, 39 insertions(+), 5 deletions(-)

diff --git a/lib/rpc.js b/lib/rpc.js
index 5d8380c3..e69275dc 100644
--- a/lib/rpc.js
+++ b/lib/rpc.js
@@ -167,7 +167,14 @@ function sendRequest(command, data) {
     let response = JSON.parse(request.responseText);
 
     if (!response || response.error) {
-        throw new Error((response && response.error) || 'Invalid response for "' + command + '"');
+        let error = response && response.error;
+
+        // Remove the type prefix from the error message (e.g. "Error: ").
+        if (error) {
+            error = error.replace(/^[a-z]+: /i, '');
+        }
+
+        throw new Error(error || `Invalid response for "${command}"`);
     }
 
     return response.result;
diff --git a/lib/util.js b/lib/util.js
index ded21bcd..6ea4f95c 100644
--- a/lib/util.js
+++ b/lib/util.js
@@ -11,7 +11,6 @@ const {keys} = constants;
 const mutationListeners = {};
 
 module.exports = {
-    addMutationListener,
     fireMutationListeners,
     createList,
     createMethods,
@@ -25,6 +24,13 @@ function addMutationListener(realmId, callback) {
     listeners.add(callback);
 }
 
+function removeMutationListener(realmId, callback) {
+    let listeners = mutationListeners[realmId];
+    if (listeners) {
+        listeners.delete(callback);
+    }
+}
+
 function fireMutationListeners(realmId) {
     let listeners = mutationListeners[realmId];
     if (listeners) {
@@ -87,7 +93,19 @@ function createList(prototype, realmId, info, mutable) {
     list[keys.type] = info.type;
 
     resize(info.size);
-    addMutationListener(realmId, resize);
+
+    addMutationListener(realmId, function listener() {
+        try {
+            resize();
+        } catch (e) {
+            // If the error indicates the list was deleted, then remove this listener.
+            if (e.message == 'Tableview is not attached') {
+                removeMutationListener(realmId, listener);
+            } else {
+                throw e;
+            }
+        }
+    });
 
     return list;
 }
diff --git a/tests/lib/ArrayTests.js b/tests/lib/ArrayTests.js
index 25950511..f5110179 100644
--- a/tests/lib/ArrayTests.js
+++ b/tests/lib/ArrayTests.js
@@ -276,11 +276,12 @@ module.exports = BaseTest.extend({
 
     testDeletions: function() {
         var realm = new Realm({schema: [schemas.LinkTypes, schemas.TestObject]});
+        var object;
         var array;
 
         realm.write(function() {
-            var obj = realm.create('LinkTypesObject', [[1], [2], [[3], [4]]]);
-            array = obj.arrayCol;
+            object = realm.create('LinkTypesObject', [[1], [2], [[3], [4]]]);
+            array = object.arrayCol;
         });
 
         try {
@@ -296,6 +297,14 @@ module.exports = BaseTest.extend({
 
         TestCase.assertEqual(array.length, 2);
         TestCase.assertEqual(array[0].doubleCol, 3);
+
+        realm.write(function() {
+            realm.delete(object);
+        });
+
+        TestCase.assertThrows(function() {
+            array[0];
+        });
     },
 
     testLiveUpdatingResults: function() {