Delay loading implicit import

As a performance improvement to avoid accessing the filesystem
unnecessarily, only import "." implicitly if types cannot be found in the
existing imports. This is not a behavior change for type resolution,
because "." already has the lowest precedence for type resolution.

Change-Id: I5ac2a9fac85559eb96cba93c29d17068fe8171da
Manual cherry-pick of qtquick1/dc96bfd00152e25f007511f64bff7c413f657886
Reviewed-by: Christopher Adams <chris.adams@jollamobile.com>

3 files changed, 32 insertions, 0 deletions

diff --git a/tests/auto/declarative/qdeclarativelanguage/data/LocalLast2.qml b/tests/auto/declarative/qdeclarativelanguage/data/LocalLast2.qml
new file mode 100644
index 0000000000..4bf7eb2ec3
--- /dev/null
+++ b/tests/auto/declarative/qdeclarativelanguage/data/LocalLast2.qml
@@ -0,0 +1,2 @@
+import QtQuick 1.0
+MouseArea {}
diff --git a/tests/auto/declarative/qdeclarativelanguage/data/localOrderTest.qml b/tests/auto/declarative/qdeclarativelanguage/data/localOrderTest.qml
new file mode 100644
index 0000000000..d5db212091
--- /dev/null
+++ b/tests/auto/declarative/qdeclarativelanguage/data/localOrderTest.qml
@@ -0,0 +1,7 @@
+import QtQuick 1.0
+import org.qtproject.installedtest 1.0
+
+LocalLast2 {
+    property QtObject item: LocalLast {}
+}
+
diff --git a/tests/auto/declarative/qdeclarativelanguage/tst_qdeclarativelanguage.cpp b/tests/auto/declarative/qdeclarativelanguage/tst_qdeclarativelanguage.cpp
index 40ff989953..6068dfd9d3 100644
--- a/tests/auto/declarative/qdeclarativelanguage/tst_qdeclarativelanguage.cpp
+++ b/tests/auto/declarative/qdeclarativelanguage/tst_qdeclarativelanguage.cpp
@@ -136,6 +136,7 @@ private slots:
     void reservedWords();
     void inlineAssignmentsOverrideBindings();
     void nestedComponentRoots();
+    void implicitImportsLast();
 
     void basicRemote_data();
     void basicRemote();
@@ -1820,6 +1821,11 @@ void tst_qdeclarativelanguage::importsOrder_data()
            "LocalLast {}"
            << (!qmlCheckTypes()?"QDeclarativeRectangle":"")// i.e. from org.qtproject.installedtest, not data/LocalLast.qml
            << (!qmlCheckTypes()?"":"LocalLast is ambiguous. Found in lib/org/qtproject/installedtest and in local directory");
+    QTest::newRow("local last 3") <<
+           "import org.qtproject.installedtest 1.0\n"
+           "LocalLast {LocalLast2{}}"
+           << (!qmlCheckTypes()?"QDeclarativeRectangle":"")// i.e. from org.qtproject.installedtest, not data/LocalLast.qml
+           << (!qmlCheckTypes()?"":"LocalLast is ambiguous. Found in lib/org/qtproject/installedtest and in local directory");
 }
 
 void tst_qdeclarativelanguage::importsOrder()
@@ -2024,6 +2030,23 @@ void tst_qdeclarativelanguage::aliasPropertyChangeSignals()
     }
 }
 
+// Tests that the implicit import has lowest precedence, in the case where
+// there are conflicting types and types only found in the local import.
+// Tests that just check one (or the root) type are in ::importsOrder
+void tst_qdeclarativelanguage::implicitImportsLast()
+{
+    if (qmlCheckTypes())
+        QSKIP("This test is about maintaining the same choice when type is ambiguous.", SkipAll);
+    QDeclarativeComponent component(&engine, TEST_FILE("localOrderTest.qml"));
+    VERIFY_ERRORS(0);
+    QObject *object = qobject_cast<QObject *>(component.create());
+    QVERIFY(object != 0);
+    QVERIFY(QString(object->metaObject()->className()).startsWith(QLatin1String("QDeclarativeMouseArea")));
+    QObject* object2 = object->property("item").value<QObject*>();
+    QVERIFY(object2 != 0);
+    QCOMPARE(QString(object2->metaObject()->className()), QLatin1String("QDeclarativeRectangle"));
+}
+
 QTEST_MAIN(tst_qdeclarativelanguage)
 
 #include "tst_qdeclarativelanguage.moc"