Merge pull request #1109 from realm/fsa_fix_handover_tests_2

fix for critical bug in query handover and minor bug in TableView::re_sort, and improvements to tests

release_notes.md

@@ -21,6 +21,9 @@
 * `Expression` subclasses now update `Query`s current descriptor after setting
   the table. This prevents a null dereference when adding further conditions
   to the query.
+* A bug in `Query` copying has been fixed. The bug could cause references to
+  Tables which should stay under the supervision of one SharedGroup to leak 
+  to another during handover_export() leading to corruption.
 
 ### API breaking changes:
 

src/realm/query.cpp

@@ -97,10 +97,6 @@ Query::Query(const Query& copy, const TCopyExpressionTag&)
 
 void Query::copy_nodes(const Query& source)
 {
-        m_table = source.m_table;
-        m_view = source.m_view;
-        m_source_link_view = source.m_source_link_view;
-
         create();
 
         first = source.first;
@@ -146,6 +142,7 @@ Query& Query::operator = (const Query& source)
         m_view = source.m_view;
         m_source_link_view = source.m_source_link_view;
         m_source_table_view = source.m_source_table_view;
+
         copy_nodes(source);
     }
     return *this;

src/realm/views.cpp

@@ -27,7 +27,7 @@ void RowIndexes::sort(Sorter& sorting_predicate)
     sorting_predicate.init(this);
     std::stable_sort(v.begin(), v.end(), sorting_predicate);
     m_row_indexes.clear();
-    for (size_t t = 0; t < sz; t++)
+    for (size_t t = 0; t < sz - detached_ref_count; t++)
         m_row_indexes.add(v[t]);
     for (size_t t = 0; t < detached_ref_count; ++t)
         m_row_indexes.add(-1);

src/realm/views.hpp

@@ -60,7 +60,8 @@ class RowIndexes
     struct Sorter
     {
         Sorter(){}
-        Sorter(std::vector<size_t> columns, std::vector<bool> ascending) : m_column_indexes(columns), m_ascending(ascending) {}
+        Sorter(const std::vector<size_t>& columns, const std::vector<bool>& ascending) 
+            : m_column_indexes(columns), m_ascending(ascending) {}
         bool operator()(size_t i, size_t j) const
         {
             for (size_t t = 0; t < m_columns.size(); t++) {

test/test_lang_bind_helper.cpp

@@ -8188,6 +8188,7 @@ void handover_querier(HandoverControl<SharedGroup::Handover<TableView>>* control
         // here we need to allow the reciever to get hold on the proper version before
         // we go through the loop again and advance_read().
         control->wait_feedback();
+        sched_yield();
 
         if (table->size() > 0 && table->get_int(0,0) == 0)
             break;
@@ -8206,17 +8207,21 @@ void handover_verifier(HandoverControl<SharedGroup::Handover<TableView>>* contro
         std::unique_ptr<SharedGroup::Handover<TableView>> handover;
         SharedGroup::VersionID version;
         control->get(handover, version);
+        CHECK_EQUAL(version.version, handover->version.version);
+        CHECK(version == handover->version);
         Group& g = const_cast<Group&>(sg.begin_read(version));
+        CHECK_EQUAL(version.version, sg.get_version_of_current_transaction().version);
+        CHECK(version == sg.get_version_of_current_transaction());
         control->signal_feedback();
         TableRef table = g.get_table("table");
         TableView tv = table->where().greater(0,50).find_all();
         CHECK(tv.is_in_sync());
         std::unique_ptr<TableView> tv2 = sg.import_from_handover(move(handover));
         CHECK(tv.is_in_sync());
         CHECK(tv2->is_in_sync());
-        CHECK(tv.size() == tv2->size());
+        CHECK_EQUAL(tv.size(), tv2->size());
         for (std::size_t k=0; k<tv.size(); ++k)
-            CHECK(tv.get_int(0,k) == tv2->get_int(0,k));
+            CHECK_EQUAL(tv.get_int(0,k), tv2->get_int(0,k));
         if (table->size() > 0 && table->get_int(0,0) == 0)
             break;
         sg.end_read();