Feature : Update entries across groups when merging (#807)

* Feature : Update entries across groups when merging

* Styling

.gitignore

@@ -6,3 +6,4 @@ release*/
 *.kdev4
 
 \.vscode/
+*.swp

src/core/Group.cpp

@@ -488,16 +488,15 @@ Entry* Group::findEntry(QString entryId)
 {
     Q_ASSERT(!entryId.isNull());
 
+    Entry* entry;
     if (Uuid::isUuid(entryId)) {
-        Uuid entryUuid = Uuid::fromHex(entryId);
+        entry = findEntryByUuid(Uuid::fromHex(entryId));
-        for (Entry* entry : entriesRecursive(false)) {
+        if (entry) {
-            if (entry->uuid() == entryUuid) {
             return entry;
         }
     }
-    }
 
-    Entry* entry = findEntryByPath(entryId);
+    entry = findEntryByPath(entryId);
     if (entry) {
         return entry;
     }
@@ -514,7 +513,7 @@ Entry* Group::findEntry(QString entryId)
 Entry* Group::findEntryByUuid(const Uuid& uuid)
 {
     Q_ASSERT(!uuid.isNull());
-    for (Entry* entry : asConst(m_entries)) {
+    for (Entry* entry : entriesRecursive(false)) {
         if (entry->uuid() == uuid) {
             return entry;
         }
@@ -575,7 +574,6 @@ Group* Group::findGroupByPath(QString groupPath, QString basePath)
     }
 
     return nullptr;
-
 }
 
 QString Group::print(bool recursive, int depth)
@@ -655,25 +653,44 @@ QSet<Uuid> Group::customIconsRecursive() const
 
 void Group::merge(const Group* other)
 {
+
+    Group* rootGroup = this;
+    while (rootGroup->parentGroup()) {
+        rootGroup = rootGroup->parentGroup();
+    }
+
     // merge entries
     const QList<Entry*> dbEntries = other->entries();
     for (Entry* entry : dbEntries) {
-        // entries are searched by uuid
+
-        if (!findEntryByUuid(entry->uuid())) {
+        Entry* existingEntry = rootGroup->findEntryByUuid(entry->uuid());
+
+        // This entry does not exist at all. Create it.
+        if (!existingEntry) {
+            qDebug("New entry %s detected. Creating it.", qPrintable(entry->title()));
             entry->clone(Entry::CloneNoFlags)->setGroup(this);
+        // Entry is already present in the database. Update it.
         } else {
-            resolveConflict(findEntryByUuid(entry->uuid()), entry);
+            bool locationChanged = existingEntry->timeInfo().locationChanged() < entry->timeInfo().locationChanged();
+            if (locationChanged && existingEntry->group() != this) {
+                existingEntry->setGroup(this);
+                qDebug("Location changed for entry %s. Updating it", qPrintable(existingEntry->title()));
+            }
+            resolveConflict(existingEntry, entry);
         }
     }
 
-    // merge groups (recursively)
+    // merge groups recursively
     const QList<Group*> dbChildren = other->children();
     for (Group* group : dbChildren) {
         // groups are searched by name instead of uuid
         if (findChildByName(group->name())) {
             findChildByName(group->name())->merge(group);
         } else {
-            group->setParent(this);
+            qDebug("New group %s detected. Creating it.", qPrintable(group->name()));
+            Group* newGroup = group->clone(Entry::CloneNoFlags, true);
+            newGroup->setParent(this);
+            newGroup->merge(group);
         }
     }
 
@@ -691,7 +708,7 @@ Group* Group::findChildByName(const QString& name)
     return nullptr;
 }
 
-Group* Group::clone(Entry::CloneFlags entryFlags) const
+Group* Group::clone(Entry::CloneFlags entryFlags, bool shallow) const
 {
     Group* clonedGroup = new Group();
 
@@ -700,6 +717,7 @@ Group* Group::clone(Entry::CloneFlags entryFlags) const
     clonedGroup->setUuid(Uuid::random());
     clonedGroup->m_data = m_data;
 
+    if (!shallow) {
         const QList<Entry*> entryList = entries();
         for (Entry* entry : entryList) {
             Entry* clonedEntry = entry->clone(entryFlags);
@@ -711,6 +729,7 @@ Group* Group::clone(Entry::CloneFlags entryFlags) const
             Group* clonedGroupChild = groupChild->clone(entryFlags);
             clonedGroupChild->setParent(clonedGroup);
         }
+    }
 
     clonedGroup->setUpdateTimeinfo(true);
 
@@ -829,8 +848,7 @@ void Group::markOlderEntry(Entry* entry)
 {
     entry->attributes()->set(
         "merged",
-        QString("older entry merged from database \"%1\"").arg(entry->group()->database()->metadata()->name())
+        QString("older entry merged from database \"%1\"").arg(entry->group()->database()->metadata()->name()));
-    );
 }
 
 bool Group::resolveSearchingEnabled() const
@@ -884,20 +902,22 @@ void Group::resolveConflict(Entry* existingEntry, Entry* otherEntry)
     case KeepBoth:
         // if one entry is newer, create a clone and add it to the group
         if (timeExisting > timeOther) {
-                clonedEntry = otherEntry->clone(Entry::CloneNoFlags);
+            clonedEntry = otherEntry->clone(Entry::CloneNewUuid);
             clonedEntry->setGroup(this);
             markOlderEntry(clonedEntry);
         } else if (timeExisting < timeOther) {
-                clonedEntry = otherEntry->clone(Entry::CloneNoFlags);
+            clonedEntry = otherEntry->clone(Entry::CloneNewUuid);
             clonedEntry->setGroup(this);
             markOlderEntry(existingEntry);
         }
         break;
     case KeepNewer:
         if (timeExisting < timeOther) {
+            qDebug("Updating entry %s.", qPrintable(existingEntry->title()));
             // only if other entry is newer, replace existing one
-                removeEntry(existingEntry);
+            Group* currentGroup = existingEntry->group();
-                addEntry(otherEntry->clone(Entry::CloneNoFlags));
+            currentGroup->removeEntry(existingEntry);
+            otherEntry->clone(Entry::CloneNoFlags)->setGroup(currentGroup);
         }
 
         break;
@@ -928,5 +948,4 @@ QStringList Group::locate(QString locateTerm, QString currentPath)
     }
 
     return response;
-
 }

src/core/Group.h

@@ -117,13 +117,14 @@ public:
     QList<Group*> groupsRecursive(bool includeSelf);
     QSet<Uuid> customIconsRecursive() const;
     /**
-     * Creates a duplicate of this group including all child entries and groups.
+     * Creates a duplicate of this group including all child entries and groups (if not shallow).
      * The exceptions are that the returned group doesn't have a parent group
      * and all TimeInfo attributes are set to the current time.
      * Note that you need to copy the custom icons manually when inserting the
      * new group into another database.
      */
-    Group* clone(Entry::CloneFlags entryFlags = Entry::CloneNewUuid | Entry::CloneResetTimeInfo) const;
+    Group* clone(Entry::CloneFlags entryFlags = Entry::CloneNewUuid | Entry::CloneResetTimeInfo,
+                 bool shallow = false) const;
     void copyDataFrom(const Group* other);
     void merge(const Group* other);
     QString print(bool recursive = false, int depth = 0);

tests/CMakeLists.txt

@@ -158,6 +158,9 @@ endif()
 add_unit_test(NAME testentry SOURCES TestEntry.cpp
               LIBS ${TEST_LIBRARIES})
 
+add_unit_test(NAME testmerge SOURCES TestMerge.cpp
+              LIBS ${TEST_LIBRARIES})
+
 add_unit_test(NAME testtotp SOURCES TestTotp.cpp
               LIBS ${TEST_LIBRARIES})
 

tests/TestGroup.cpp

@@ -452,123 +452,6 @@ void TestGroup::testCopyCustomIcons()
     delete dbSource;
 }
 
-void TestGroup::testMerge()
-{
-    Group* group1 = new Group();
-    group1->setName("group 1");
-    Group* group2 = new Group();
-    group2->setName("group 2");
-
-    Entry* entry1 = new Entry();
-    Entry* entry2 = new Entry();
-
-    entry1->setGroup(group1);
-    entry1->setUuid(Uuid::random());
-    entry2->setGroup(group1);
-    entry2->setUuid(Uuid::random());
-
-    group2->merge(group1);
-
-    QCOMPARE(group1->entries().size(), 2);
-    QCOMPARE(group2->entries().size(), 2);
-}
-
-void TestGroup::testMergeDatabase()
-{
-    Database* dbSource = createMergeTestDatabase();
-    Database* dbDest = new Database();
-
-    dbDest->merge(dbSource);
-
-    QCOMPARE(dbDest->rootGroup()->children().size(), 2);
-    QCOMPARE(dbDest->rootGroup()->children().at(0)->entries().size(), 2);
-
-    delete dbDest;
-    delete dbSource;
-}
-
-void TestGroup::testMergeConflict()
-{
-    Database* dbSource = createMergeTestDatabase();
-
-    // test merging updated entries
-    // falls back to KeepBoth mode
-    Database* dbCopy = new Database();
-    dbCopy->setRootGroup(dbSource->rootGroup()->clone(Entry::CloneNoFlags));
-
-    // sanity check
-    QCOMPARE(dbCopy->rootGroup()->children().at(0)->entries().size(), 2);
-
-    // make this entry newer than in original db
-    Entry* updatedEntry = dbCopy->rootGroup()->children().at(0)->entries().at(0);
-    TimeInfo updatedTimeInfo = updatedEntry->timeInfo();
-    updatedTimeInfo.setLastModificationTime(updatedTimeInfo.lastModificationTime().addYears(1));
-    updatedEntry->setTimeInfo(updatedTimeInfo);
-
-    dbCopy->merge(dbSource);
-
-    // one entry is duplicated because of mode
-    QCOMPARE(dbCopy->rootGroup()->children().at(0)->entries().size(), 2);
-
-    delete dbSource;
-    delete dbCopy;
-}
-
-void TestGroup::testMergeConflictKeepBoth()
-{
-    Database* dbSource = createMergeTestDatabase();
-
-    // test merging updated entries
-    // falls back to KeepBoth mode
-    Database* dbCopy = new Database();
-    dbCopy->setRootGroup(dbSource->rootGroup()->clone(Entry::CloneNoFlags));
-
-    // sanity check
-    QCOMPARE(dbCopy->rootGroup()->children().at(0)->entries().size(), 2);
-
-    // make this entry newer than in original db
-    Entry* updatedEntry = dbCopy->rootGroup()->children().at(0)->entries().at(0);
-    TimeInfo updatedTimeInfo = updatedEntry->timeInfo();
-    updatedTimeInfo.setLastModificationTime(updatedTimeInfo.lastModificationTime().addYears(1));
-    updatedEntry->setTimeInfo(updatedTimeInfo);
-
-    dbCopy->rootGroup()->setMergeMode(Group::MergeMode::KeepBoth);
-
-    dbCopy->merge(dbSource);
-
-    // one entry is duplicated because of mode
-    QCOMPARE(dbCopy->rootGroup()->children().at(0)->entries().size(), 3);
-    // the older entry was merged from the other db as last in the group
-    Entry* olderEntry = dbCopy->rootGroup()->children().at(0)->entries().at(2);
-    QVERIFY2(olderEntry->attributes()->hasKey("merged"), "older entry is marked with an attribute \"merged\"");
-
-    delete dbSource;
-    delete dbCopy;
-}
-
-Database* TestGroup::createMergeTestDatabase()
-{
-    Database* db = new Database();
-
-    Group* group1 = new Group();
-    group1->setName("group 1");
-    Group* group2 = new Group();
-    group2->setName("group 2");
-
-    Entry* entry1 = new Entry();
-    Entry* entry2 = new Entry();
-
-    entry1->setGroup(group1);
-    entry1->setUuid(Uuid::random());
-    entry2->setGroup(group1);
-    entry2->setUuid(Uuid::random());
-
-    group1->setParent(db->rootGroup());
-    group2->setParent(db->rootGroup());
-
-    return db;
-}
-
 void TestGroup::testFindEntry()
 {
     Database* db = new Database();

tests/TestGroup.h

@@ -35,17 +35,10 @@ private slots:
     void testCopyCustomIcon();
     void testClone();
     void testCopyCustomIcons();
-    void testMerge();
-    void testMergeConflict();
-    void testMergeDatabase();
-    void testMergeConflictKeepBoth();
     void testFindEntry();
     void testFindGroupByPath();
     void testPrint();
     void testLocate();
-
-private:
-    Database* createMergeTestDatabase();
 };
 
 #endif // KEEPASSX_TESTGROUP_H

tests/TestMerge.cpp

@@ -0,0 +1,445 @@
+/*
+ *  Copyright (C) 2017 KeePassXC Team <team@keepassxc.org>
+ *
+ *  This program is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation, either version 2 or (at your option)
+ *  version 3 of the License.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "TestMerge.h"
+
+#include <QDebug>
+#include <QTest>
+
+#include "core/Database.h"
+#include "core/Group.h"
+#include "core/Metadata.h"
+#include "crypto/Crypto.h"
+
+QTEST_GUILESS_MAIN(TestMerge)
+
+void TestMerge::initTestCase()
+{
+    qRegisterMetaType<Entry*>("Entry*");
+    qRegisterMetaType<Group*>("Group*");
+    QVERIFY(Crypto::init());
+}
+
+/**
+ * Merge an existing database into a new one.
+ * All the entries of the existing should end
+ * up in the new one.
+ */
+void TestMerge::testMergeIntoNew()
+{
+    Database* dbSource = createTestDatabase();
+    Database* dbDestination = new Database();
+
+    dbDestination->merge(dbSource);
+
+    QCOMPARE(dbDestination->rootGroup()->children().size(), 2);
+    QCOMPARE(dbDestination->rootGroup()->children().at(0)->entries().size(), 2);
+
+    delete dbDestination;
+    delete dbSource;
+}
+
+/**
+ * Merging when no changes occured should not
+ * have any side effect.
+ */
+void TestMerge::testMergeNoChanges()
+{
+    Database* dbDestination = createTestDatabase();
+
+    Database* dbSource = new Database();
+    dbSource->setRootGroup(dbDestination->rootGroup()->clone(Entry::CloneNoFlags));
+
+    QCOMPARE(dbDestination->rootGroup()->entriesRecursive().size(), 2);
+    QCOMPARE(dbSource->rootGroup()->entriesRecursive().size(), 2);
+
+    dbDestination->merge(dbSource);
+
+    QCOMPARE(dbDestination->rootGroup()->entriesRecursive().size(), 2);
+    QCOMPARE(dbSource->rootGroup()->entriesRecursive().size(), 2);
+
+    dbDestination->merge(dbSource);
+
+    QCOMPARE(dbDestination->rootGroup()->entriesRecursive().size(), 2);
+    QCOMPARE(dbSource->rootGroup()->entriesRecursive().size(), 2);
+
+    delete dbDestination;
+    delete dbSource;
+}
+
+/**
+ * If the entry is updated in the source database, the update
+ * should propagate in the destination database.
+ */
+void TestMerge::testResolveConflictNewer()
+{
+    Database* dbDestination = createTestDatabase();
+
+    Database* dbSource = new Database();
+    dbSource->setRootGroup(dbDestination->rootGroup()->clone(Entry::CloneNoFlags));
+
+    // sanity check
+    Group* group1 = dbSource->rootGroup()->findChildByName("group1");
+    QVERIFY(group1 != nullptr);
+    QCOMPARE(group1->entries().size(), 2);
+
+    Entry* entry1 = dbSource->rootGroup()->findEntry("entry1");
+    QVERIFY(entry1 != nullptr);
+
+    // Make sure the two changes have a different timestamp.
+    QTest::qSleep(1);
+    // make this entry newer than in destination db
+    entry1->beginUpdate();
+    entry1->setPassword("password");
+    entry1->endUpdate();
+
+    dbDestination->merge(dbSource);
+
+    // sanity check
+    group1 = dbDestination->rootGroup()->findChildByName("group1");
+    QVERIFY(group1 != nullptr);
+    QCOMPARE(group1->entries().size(), 2);
+
+    entry1 = dbDestination->rootGroup()->findEntry("entry1");
+    QVERIFY(entry1 != nullptr);
+    QCOMPARE(entry1->password(), QString("password"));
+
+    // When updating an entry, it should not end up in the
+    // deleted objects.
+    for (DeletedObject deletedObject : dbDestination->deletedObjects()) {
+        QVERIFY(deletedObject.uuid != entry1->uuid());
+    }
+
+    delete dbDestination;
+    delete dbSource;
+}
+
+/**
+ * If the entry is updated in the source database, and the
+ * destination database after, the entry should remain the
+ * same.
+ */
+void TestMerge::testResolveConflictOlder()
+{
+    Database* dbDestination = createTestDatabase();
+
+    Database* dbSource = new Database();
+    dbSource->setRootGroup(dbDestination->rootGroup()->clone(Entry::CloneNoFlags));
+
+    // sanity check
+    Group* group1 = dbSource->rootGroup()->findChildByName("group1");
+    QVERIFY(group1 != nullptr);
+    QCOMPARE(group1->entries().size(), 2);
+
+    Entry* entry1 = dbSource->rootGroup()->findEntry("entry1");
+    QVERIFY(entry1 != nullptr);
+
+    // Make sure the two changes have a different timestamp.
+    QTest::qSleep(1);
+    // make this entry newer than in destination db
+    entry1->beginUpdate();
+    entry1->setPassword("password1");
+    entry1->endUpdate();
+
+    entry1 = dbDestination->rootGroup()->findEntry("entry1");
+    QVERIFY(entry1 != nullptr);
+
+    // Make sure the two changes have a different timestamp.
+    QTest::qSleep(1);
+    // make this entry newer than in destination db
+    entry1->beginUpdate();
+    entry1->setPassword("password2");
+    entry1->endUpdate();
+
+    dbDestination->merge(dbSource);
+
+    // sanity check
+    group1 = dbDestination->rootGroup()->findChildByName("group1");
+    QVERIFY(group1 != nullptr);
+    QCOMPARE(group1->entries().size(), 2);
+
+    entry1 = dbDestination->rootGroup()->findEntry("entry1");
+    QVERIFY(entry1 != nullptr);
+    QCOMPARE(entry1->password(), QString("password2"));
+
+    // When updating an entry, it should not end up in the
+    // deleted objects.
+    for (DeletedObject deletedObject : dbDestination->deletedObjects()) {
+        QVERIFY(deletedObject.uuid != entry1->uuid());
+    }
+
+    delete dbDestination;
+    delete dbSource;
+}
+
+/**
+ * Tests the KeepBoth merge mode.
+ */
+void TestMerge::testResolveConflictKeepBoth()
+{
+    Database* dbDestination = createTestDatabase();
+
+    Database* dbSource = new Database();
+    dbSource->setRootGroup(dbDestination->rootGroup()->clone(Entry::CloneNoFlags));
+
+    // sanity check
+    QCOMPARE(dbDestination->rootGroup()->children().at(0)->entries().size(), 2);
+
+    // make this entry newer than in original db
+    Entry* updatedEntry = dbDestination->rootGroup()->children().at(0)->entries().at(0);
+    TimeInfo updatedTimeInfo = updatedEntry->timeInfo();
+    updatedTimeInfo.setLastModificationTime(updatedTimeInfo.lastModificationTime().addYears(1));
+    updatedEntry->setTimeInfo(updatedTimeInfo);
+
+    dbDestination->rootGroup()->setMergeMode(Group::MergeMode::KeepBoth);
+
+    dbDestination->merge(dbSource);
+
+    // one entry is duplicated because of mode
+    QCOMPARE(dbDestination->rootGroup()->children().at(0)->entries().size(), 3);
+    // the older entry was merged from the other db as last in the group
+    Entry* olderEntry = dbDestination->rootGroup()->children().at(0)->entries().at(2);
+    QVERIFY2(olderEntry->attributes()->hasKey("merged"), "older entry is marked with an attribute \"merged\"");
+
+    QVERIFY2(olderEntry->uuid().toHex() != updatedEntry->uuid().toHex(),
+             "KeepBoth should not reuse the UUIDs when cloning.");
+
+    delete dbSource;
+    delete dbDestination;
+}
+
+/**
+ * The location of an entry should be updated in the
+ * destination database.
+ */
+void TestMerge::testMoveEntry()
+{
+    Database* dbDestination = createTestDatabase();
+
+    Database* dbSource = new Database();
+    dbSource->setRootGroup(dbDestination->rootGroup()->clone(Entry::CloneNoFlags));
+
+    Entry* entry1 = dbSource->rootGroup()->findEntry("entry1");
+    QVERIFY(entry1 != nullptr);
+
+    Group* group2 = dbSource->rootGroup()->findChildByName("group2");
+    QVERIFY(group2 != nullptr);
+
+    // Make sure the two changes have a different timestamp.
+    QTest::qSleep(1);
+    entry1->setGroup(group2);
+    QCOMPARE(entry1->group()->name(), QString("group2"));
+
+    dbDestination->merge(dbSource);
+
+    entry1 = dbDestination->rootGroup()->findEntry("entry1");
+    QVERIFY(entry1 != nullptr);
+    QCOMPARE(entry1->group()->name(), QString("group2"));
+    QCOMPARE(dbDestination->rootGroup()->entriesRecursive().size(), 2);
+
+    delete dbDestination;
+    delete dbSource;
+}
+
+/**
+ * The location of an entry should be updated in the
+ * destination database, but changes from the destination
+ * database should be preserved.
+ */
+void TestMerge::testMoveEntryPreserveChanges()
+{
+    Database* dbDestination = createTestDatabase();
+
+    Database* dbSource = new Database();
+    dbSource->setRootGroup(dbDestination->rootGroup()->clone(Entry::CloneNoFlags));
+
+    Entry* entry1 = dbSource->rootGroup()->findEntry("entry1");
+    QVERIFY(entry1 != nullptr);
+
+    Group* group2 = dbSource->rootGroup()->findChildByName("group2");
+    QVERIFY(group2 != nullptr);
+
+    QTest::qSleep(1);
+    entry1->setGroup(group2);
+    QCOMPARE(entry1->group()->name(), QString("group2"));
+
+    entry1 = dbDestination->rootGroup()->findEntry("entry1");
+    QVERIFY(entry1 != nullptr);
+
+    QTest::qSleep(1);
+    entry1->beginUpdate();
+    entry1->setPassword("password");
+    entry1->endUpdate();
+
+    dbDestination->merge(dbSource);
+
+    entry1 = dbDestination->rootGroup()->findEntry("entry1");
+    QVERIFY(entry1 != nullptr);
+    QCOMPARE(entry1->group()->name(), QString("group2"));
+    QCOMPARE(dbDestination->rootGroup()->entriesRecursive().size(), 2);
+    QCOMPARE(entry1->password(), QString("password"));
+
+    delete dbDestination;
+    delete dbSource;
+}
+
+void TestMerge::testCreateNewGroups()
+{
+    Database* dbDestination = createTestDatabase();
+
+    Database* dbSource = new Database();
+    dbSource->setRootGroup(dbDestination->rootGroup()->clone(Entry::CloneNoFlags));
+
+    QTest::qSleep(1);
+    Group* group3 = new Group();
+    group3->setName("group3");
+    group3->setParent(dbSource->rootGroup());
+
+    dbDestination->merge(dbSource);
+
+    group3 = dbDestination->rootGroup()->findChildByName("group3");
+    QVERIFY(group3 != nullptr);
+    QCOMPARE(group3->name(), QString("group3"));
+
+    delete dbDestination;
+    delete dbSource;
+}
+
+void TestMerge::testMoveEntryIntoNewGroup()
+{
+    Database* dbDestination = createTestDatabase();
+
+    Database* dbSource = new Database();
+    dbSource->setRootGroup(dbDestination->rootGroup()->clone(Entry::CloneNoFlags));
+
+    QTest::qSleep(1);
+    Group* group3 = new Group();
+    group3->setName("group3");
+    group3->setParent(dbSource->rootGroup());
+
+    Entry* entry1 = dbSource->rootGroup()->findEntry("entry1");
+    entry1->setGroup(group3);
+
+    dbDestination->merge(dbSource);
+
+    QCOMPARE(dbDestination->rootGroup()->entriesRecursive().size(), 2);
+
+    group3 = dbDestination->rootGroup()->findChildByName("group3");
+    QVERIFY(group3 != nullptr);
+    QCOMPARE(group3->name(), QString("group3"));
+    QCOMPARE(group3->entries().size(), 1);
+
+    entry1 = dbDestination->rootGroup()->findEntry("entry1");
+    QVERIFY(entry1 != nullptr);
+    QCOMPARE(entry1->group()->name(), QString("group3"));
+
+    delete dbDestination;
+    delete dbSource;
+}
+
+/**
+ * Even though the entries' locations are no longer
+ * the same, we will keep associating them.
+ */
+void TestMerge::testUpdateEntryDifferentLocation()
+{
+    Database* dbDestination = createTestDatabase();
+
+    Database* dbSource = new Database();
+    dbSource->setRootGroup(dbDestination->rootGroup()->clone(Entry::CloneNoFlags));
+
+    Group* group3 = new Group();
+    group3->setName("group3");
+    group3->setParent(dbDestination->rootGroup());
+
+    Entry* entry1 = dbDestination->rootGroup()->findEntry("entry1");
+    QVERIFY(entry1 != nullptr);
+    entry1->setGroup(group3);
+    Uuid uuidBeforeSyncing = entry1->uuid();
+
+    // Change the entry in the source db.
+    QTest::qSleep(1);
+    entry1 = dbSource->rootGroup()->findEntry("entry1");
+    QVERIFY(entry1 != nullptr);
+    entry1->beginUpdate();
+    entry1->setUsername("username");
+    entry1->endUpdate();
+
+    dbDestination->merge(dbSource);
+
+    QCOMPARE(dbDestination->rootGroup()->entriesRecursive().size(), 2);
+
+    entry1 = dbDestination->rootGroup()->findEntry("entry1");
+    QVERIFY(entry1 != nullptr);
+    QVERIFY(entry1->group() != nullptr);
+    QCOMPARE(entry1->username(), QString("username"));
+    QCOMPARE(entry1->group()->name(), QString("group3"));
+    QCOMPARE(uuidBeforeSyncing, entry1->uuid());
+
+    delete dbDestination;
+    delete dbSource;
+}
+
+/**
+ * The first merge should create new entries, the
+ * second should only sync them, since they have
+ * been created with the same UUIDs.
+ */
+void TestMerge::testMergeAndSync()
+{
+    Database* dbDestination = new Database();
+    Database* dbSource = createTestDatabase();
+
+    QCOMPARE(dbDestination->rootGroup()->entriesRecursive().size(), 0);
+
+    dbDestination->merge(dbSource);
+
+    QCOMPARE(dbDestination->rootGroup()->entriesRecursive().size(), 2);
+
+    dbDestination->merge(dbSource);
+
+    // Still only 2 entries, since now we detect which are already present.
+    QCOMPARE(dbDestination->rootGroup()->entriesRecursive().size(), 2);
+
+    delete dbDestination;
+    delete dbSource;
+}
+
+Database* TestMerge::createTestDatabase()
+{
+    Database* db = new Database();
+
+    Group* group1 = new Group();
+    group1->setName("group1");
+    Group* group2 = new Group();
+    group2->setName("group2");
+
+    Entry* entry1 = new Entry();
+    Entry* entry2 = new Entry();
+
+    entry1->setGroup(group1);
+    entry1->setUuid(Uuid::random());
+    entry1->setTitle("entry1");
+    entry2->setGroup(group1);
+    entry2->setUuid(Uuid::random());
+    entry2->setTitle("entry2");
+
+    group1->setParent(db->rootGroup());
+    group2->setParent(db->rootGroup());
+
+    return db;
+}

tests/TestMerge.h

@@ -0,0 +1,46 @@
+/*
+ *  Copyright (C) 2017 KeePassXC Team <team@keepassxc.org>
+ *
+ *  This program is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation, either version 2 or (at your option)
+ *  version 3 of the License.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef KEEPASSX_TESTMERGE_H
+#define KEEPASSX_TESTMERGE_H
+
+#include "core/Database.h"
+#include <QObject>
+
+class TestMerge : public QObject
+{
+    Q_OBJECT
+
+private slots:
+    void initTestCase();
+    void testMergeIntoNew();
+    void testMergeNoChanges();
+    void testResolveConflictNewer();
+    void testResolveConflictOlder();
+    void testResolveConflictKeepBoth();
+    void testMoveEntry();
+    void testMoveEntryPreserveChanges();
+    void testMoveEntryIntoNewGroup();
+    void testCreateNewGroups();
+    void testUpdateEntryDifferentLocation();
+    void testMergeAndSync();
+
+private:
+    Database* createTestDatabase();
+};
+
+#endif // KEEPASSX_TESTMERGE_H