From 632d757014c785f4f791a04c566f4b9fa0d2e5aa Mon Sep 17 00:00:00 2001
From: Thomas Goyne <tg@realm.io>
Date: Mon, 25 Apr 2016 12:02:59 -0700
Subject: [PATCH] Always deliver results to the correct SharedGroup

If there are multiple Realm instances for a single file on a single thread due
to disabling caching we need to actually deliver the results to the appropriate
SharedGroup for each notifier rather than delivering them all to the first one.
---
 src/impl/collection_notifier.cpp | 9 ++++++---
 src/impl/collection_notifier.hpp | 6 +-----
 src/impl/realm_coordinator.cpp   | 4 ++--
 tests/list.cpp                   | 6 ++++--
 4 files changed, 13 insertions(+), 12 deletions(-)

diff --git a/src/impl/collection_notifier.cpp b/src/impl/collection_notifier.cpp
index eb92e6fa..249775da 100644
--- a/src/impl/collection_notifier.cpp
+++ b/src/impl/collection_notifier.cpp
@@ -180,10 +180,13 @@ void CollectionNotifier::prepare_handover()
     do_prepare_handover(*m_sg);
 }
 
-bool CollectionNotifier::deliver(SharedGroup& sg, std::exception_ptr err)
+bool CollectionNotifier::deliver(Realm& realm, SharedGroup& sg, std::exception_ptr err)
 {
-    if (!is_for_current_thread()) {
-        return false;
+    {
+        std::lock_guard<std::mutex> lock(m_realm_mutex);
+        if (m_realm.get() != &realm) {
+            return false;
+        }
     }
 
     if (err) {
diff --git a/src/impl/collection_notifier.hpp b/src/impl/collection_notifier.hpp
index 1d98efc8..383984d4 100644
--- a/src/impl/collection_notifier.hpp
+++ b/src/impl/collection_notifier.hpp
@@ -27,7 +27,6 @@
 #include <exception>
 #include <functional>
 #include <mutex>
-#include <thread>
 #include <unordered_map>
 
 namespace realm {
@@ -109,7 +108,7 @@ public:
 
     virtual void run() = 0;
     void prepare_handover();
-    bool deliver(SharedGroup&, std::exception_ptr);
+    bool deliver(Realm&, SharedGroup&, std::exception_ptr);
 
 protected:
     bool have_callbacks() const noexcept { return m_have_callbacks; }
@@ -124,9 +123,6 @@ private:
     virtual bool do_deliver(SharedGroup&) { return true; }
     virtual bool do_add_required_change_info(TransactionChangeInfo&) = 0;
 
-    const std::thread::id m_thread_id = std::this_thread::get_id();
-    bool is_for_current_thread() const { return m_thread_id == std::this_thread::get_id(); }
-
     mutable std::mutex m_realm_mutex;
     std::shared_ptr<Realm> m_realm;
 
diff --git a/src/impl/realm_coordinator.cpp b/src/impl/realm_coordinator.cpp
index edb0df09..09693088 100644
--- a/src/impl/realm_coordinator.cpp
+++ b/src/impl/realm_coordinator.cpp
@@ -567,7 +567,7 @@ void RealmCoordinator::advance_to_ready(Realm& realm)
 
         // Query version now matches the SG version, so we can deliver them
         for (auto& notifier : m_notifiers) {
-            if (notifier->deliver(sg, m_async_error)) {
+            if (notifier->deliver(realm, sg, m_async_error)) {
                 notifiers.push_back(notifier);
             }
         }
@@ -586,7 +586,7 @@ void RealmCoordinator::process_available_async(Realm& realm)
     {
         std::lock_guard<std::mutex> lock(m_notifier_mutex);
         for (auto& notifier : m_notifiers) {
-            if (notifier->deliver(sg, m_async_error)) {
+            if (notifier->deliver(realm, sg, m_async_error)) {
                 notifiers.push_back(notifier);
             }
         }
diff --git a/tests/list.cpp b/tests/list.cpp
index 79153e7a..4d079b03 100644
--- a/tests/list.cpp
+++ b/tests/list.cpp
@@ -211,7 +211,8 @@ TEST_CASE("list") {
             // Each of the Lists now has a different source version and state at
             // that version, so they should all see different changes despite
             // being for the same LinkList
-            advance_and_notify(*r);
+            for (auto& list : lists)
+                advance_and_notify(*list.get_realm());
 
             REQUIRE_INDICES(changes[0].insertions, 0, 1, 2);
             REQUIRE(changes[0].modifications.empty());
@@ -224,7 +225,8 @@ TEST_CASE("list") {
 
             // After making another change, they should all get the same notification
             change_list();
-            advance_and_notify(*r);
+            for (auto& list : lists)
+                advance_and_notify(*list.get_realm());
 
             for (int i = 0; i < 3; ++i) {
                 REQUIRE_INDICES(changes[i].insertions, 3);