qmljs: improve handling of qml dialects

Language::Enum -> QmlDialect
 * class instead of enum
 * moved Language specific operations to it (from Document)
 * nicer handling
QStringList -> PathsAndLanguages
 * store language along with path, to perform a correct scan and improve
   path handling

Change-Id: If69d35c63cfeb48aa670b51870916cd0c40f1916
Reviewed-by: Thomas Hartmann <Thomas.Hartmann@digia.com>

39 files changed, 751 insertions, 318 deletions

diff --git a/src/libs/qmljs/qmljs-lib.pri b/src/libs/qmljs/qmljs-lib.pri
index f4e1d88f97..756bed8ec4 100644
--- a/src/libs/qmljs/qmljs-lib.pri
+++ b/src/libs/qmljs/qmljs-lib.pri
@@ -44,7 +44,8 @@ HEADERS += \
     $$PWD/qmljsconstants.h \
     $$PWD/qmljsimportdependencies.h \
     $$PWD/qmljsviewercontext.h \
-    $$PWD/qmljsdescribevalue.h
+    $$PWD/qmljsdescribevalue.h \
+    $$PWD/qmljsdialect.h
 
 SOURCES += \
     $$PWD/qmljsbind.cpp \
@@ -80,7 +81,8 @@ SOURCES += \
     $$PWD/qmljsqrcparser.cpp \
     $$PWD/qmljsimportdependencies.cpp \
     $$PWD/qmljsviewercontext.cpp \
-    $$PWD/qmljsdescribevalue.cpp
+    $$PWD/qmljsdescribevalue.cpp \
+    $$PWD/qmljsdialect.cpp
 
 
 RESOURCES += \
diff --git a/src/libs/qmljs/qmljs.qbs b/src/libs/qmljs/qmljs.qbs
index 68ebcd51c0..1bd85d4e56 100644
--- a/src/libs/qmljs/qmljs.qbs
+++ b/src/libs/qmljs/qmljs.qbs
@@ -41,6 +41,7 @@ QtcLibrary {
             "qmljsimportdependencies.cpp", "qmljsimportdependencies.h",
             "qmljsindenter.cpp", "qmljsindenter.h",
             "qmljsinterpreter.cpp", "qmljsinterpreter.h",
+            "qmljsdialect.cpp", "qmljsdialect.h",
             "qmljslineinfo.cpp", "qmljslineinfo.h",
             "qmljslink.cpp", "qmljslink.h",
             "qmljsmodelmanagerinterface.cpp", "qmljsmodelmanagerinterface.h",
diff --git a/src/libs/qmljs/qmljsbind.cpp b/src/libs/qmljs/qmljsbind.cpp
index cc7bb31bd3..56ed80d856 100644
--- a/src/libs/qmljs/qmljsbind.cpp
+++ b/src/libs/qmljs/qmljsbind.cpp
@@ -202,18 +202,18 @@ bool Bind::visit(UiImport *ast)
         const QString importId = ast->importId.toString();
         ImportInfo import = ImportInfo::moduleImport(toString(ast->importUri), version,
                                                      importId, ast);
-        if (_doc->language() == Language::Qml) {
+        if (_doc->language() == Dialect::Qml) {
             const QString importStr = import.name() + importId;
             if (ModelManagerInterface::instance()) {
                 QmlLanguageBundles langBundles = ModelManagerInterface::instance()->extendedBundles();
-                QmlBundle qq1 = langBundles.bundleForLanguage(Language::QmlQtQuick1);
-                QmlBundle qq2 = langBundles.bundleForLanguage(Language::QmlQtQuick2);
+                QmlBundle qq1 = langBundles.bundleForLanguage(Dialect::QmlQtQuick1);
+                QmlBundle qq2 = langBundles.bundleForLanguage(Dialect::QmlQtQuick2);
                 bool isQQ1 = qq1.supportedImports().contains(importStr);
                 bool isQQ2 = qq2.supportedImports().contains(importStr);
                 if (isQQ1 && ! isQQ2)
-                    _doc->setLanguage(Language::QmlQtQuick1);
+                    _doc->setLanguage(Dialect::QmlQtQuick1);
                 if (isQQ2 && ! isQQ1)
-                    _doc->setLanguage(Language::QmlQtQuick2);
+                    _doc->setLanguage(Dialect::QmlQtQuick2);
             }
         }
         _imports += import;
diff --git a/src/libs/qmljs/qmljsbundle.cpp b/src/libs/qmljs/qmljsbundle.cpp
index 28b1d951d3..a775a2f86c 100644
--- a/src/libs/qmljs/qmljsbundle.cpp
+++ b/src/libs/qmljs/qmljsbundle.cpp
@@ -288,14 +288,14 @@ bool QmlBundle::readFrom(QString path, QStringList *errors)
     return errs.isEmpty();
 }
 
-QmlBundle QmlLanguageBundles::bundleForLanguage(Language::Enum l) const
+QmlBundle QmlLanguageBundles::bundleForLanguage(Dialect l) const
 {
     if (m_bundles.contains(l))
         return m_bundles.value(l);
     return QmlBundle();
 }
 
-void QmlLanguageBundles::mergeBundleForLanguage(Language::Enum l, const QmlBundle &bundle)
+void QmlLanguageBundles::mergeBundleForLanguage(Dialect l, const QmlBundle &bundle)
 {
     if (bundle.isEmpty())
         return;
@@ -305,14 +305,14 @@ void QmlLanguageBundles::mergeBundleForLanguage(Language::Enum l, const QmlBundl
         m_bundles.insert(l,bundle);
 }
 
-QList<Language::Enum> QmlLanguageBundles::languages() const
+QList<Dialect> QmlLanguageBundles::languages() const
 {
     return m_bundles.keys();
 }
 
 void QmlLanguageBundles::mergeLanguageBundles(const QmlLanguageBundles &o)
 {
-    foreach (Language::Enum l, o.languages())
+    foreach (Dialect l, o.languages())
         mergeBundleForLanguage(l, o.bundleForLanguage(l));
 }
 
diff --git a/src/libs/qmljs/qmljsbundle.h b/src/libs/qmljs/qmljsbundle.h
index 3026c66ffd..d5d88bb431 100644
--- a/src/libs/qmljs/qmljsbundle.h
+++ b/src/libs/qmljs/qmljsbundle.h
@@ -100,12 +100,12 @@ private:
 class QMLJS_EXPORT QmlLanguageBundles
 {
 public:
-    QmlBundle bundleForLanguage(Language::Enum l) const;
-    void mergeBundleForLanguage(Language::Enum l, const QmlBundle &bundle);
-    QList<Language::Enum> languages() const;
+    QmlBundle bundleForLanguage(Dialect l) const;
+    void mergeBundleForLanguage(Dialect l, const QmlBundle &bundle);
+    QList<Dialect> languages() const;
     void mergeLanguageBundles(const QmlLanguageBundles &);
 private:
-    QHash<Language::Enum,QmlBundle> m_bundles;
+    QHash<Dialect,QmlBundle> m_bundles;
 };
 } // namespace QmlJS
 
diff --git a/src/libs/qmljs/qmljsdialect.cpp b/src/libs/qmljs/qmljsdialect.cpp
new file mode 100644
index 0000000000..74c05629b5
--- /dev/null
+++ b/src/libs/qmljs/qmljsdialect.cpp
@@ -0,0 +1,330 @@
+/****************************************************************************
+**
+** Copyright (C) 2014 Digia Plc and/or its subsidiary(-ies).
+** Contact: http://www.qt-project.org/legal
+**
+** This file is part of Qt Creator.
+**
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and Digia.  For licensing terms and
+** conditions see http://qt.digia.com/licensing.  For further information
+** use the contact form at http://qt.digia.com/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Digia gives you certain additional
+** rights.  These rights are described in the Digia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+****************************************************************************/
+
+#include "qmljsdialect.h"
+
+namespace QmlJS {
+
+
+bool Dialect::isQmlLikeLanguage() const
+{
+    switch (m_dialect) {
+    case Dialect::Qml:
+    case Dialect::QmlQtQuick1:
+    case Dialect::QmlQtQuick2:
+    case Dialect::QmlQbs:
+    case Dialect::QmlProject:
+    case Dialect::QmlTypeInfo:
+    case Dialect::AnyLanguage:
+        return true;
+    default:
+        return false;
+    }
+}
+
+bool Dialect::isFullySupportedLanguage() const
+{
+    switch (m_dialect) {
+    case Dialect::JavaScript:
+    case Dialect::Json:
+    case Dialect::Qml:
+    case Dialect::QmlQtQuick1:
+    case Dialect::QmlQtQuick2:
+        return true;
+    case Dialect::NoLanguage:
+    case Dialect::AnyLanguage:
+    case Dialect::QmlQbs:
+    case Dialect::QmlProject:
+    case Dialect::QmlTypeInfo:
+        break;
+    }
+    return false;
+}
+
+bool Dialect::isQmlLikeOrJsLanguage() const
+{
+    switch (m_dialect) {
+    case Dialect::Qml:
+    case Dialect::QmlQtQuick1:
+    case Dialect::QmlQtQuick2:
+    case Dialect::QmlQbs:
+    case Dialect::QmlProject:
+    case Dialect::QmlTypeInfo:
+    case Dialect::JavaScript:
+    case Dialect::AnyLanguage:
+        return true;
+    default:
+        return false;
+    }
+}
+
+QString Dialect::toString() const
+{
+    switch (m_dialect) {
+    case Dialect::JavaScript:
+        return QLatin1String("JavaScript");
+    case Dialect::Json:
+        return QLatin1String("Json");
+    case Dialect::Qml:
+        return QLatin1String("Qml");
+    case Dialect::QmlQtQuick1:
+        return QLatin1String("QmlQtQuick1");
+    case Dialect::QmlQtQuick2:
+        return QLatin1String("QmlQtQuick2");
+    case Dialect::NoLanguage:
+        return QLatin1String("NoLanguage");
+    case Dialect::AnyLanguage:
+        return QLatin1String("AnyLanguage");
+    case Dialect::QmlQbs:
+        return QLatin1String("QmlQbs");
+    case Dialect::QmlProject:
+        return QLatin1String("QmlProject");
+    case Dialect::QmlTypeInfo:
+        break;
+    }
+    return QLatin1String("QmlTypeInfo");
+}
+
+bool Dialect::operator ==(const Dialect &o) const {
+    return m_dialect == o.m_dialect;
+}
+
+bool Dialect::operator <(const Dialect &o) const {
+    return m_dialect < o.m_dialect;
+}
+
+Dialect Dialect::mergeLanguages(const Dialect &l1, const Dialect &l2)
+{
+    if (l1 == Dialect::NoLanguage)
+        return l2;
+    if (l2 == Dialect::NoLanguage)
+        return l1;
+    QList<Dialect> ll1 = l1.companionLanguages();
+    QList<Dialect> ll2 = l2.companionLanguages();
+    bool i1 = ll1.contains(l2);
+    bool i2 = ll2.contains(l1);
+    if (i1 && i2) {
+        if (ll1.size() > ll2.size())
+            return l1;
+        if (ll2.size() > ll1.size())
+            return l2;
+        if (l1 < l2)
+            return l1;
+        return l2;
+    }
+    if (i1 && !i2)
+        return l1;
+    if (i2 && !i1)
+        return l2;
+    QList<Dialect> qmlLangs = Dialect(Qml).companionLanguages();
+    if (qmlLangs.contains(l1) && qmlLangs.contains(l2))
+        return Dialect::Qml;
+    return Dialect::AnyLanguage;
+}
+
+void Dialect::mergeLanguage(const Dialect &l2) {
+    *this = mergeLanguages(*this, l2);
+}
+
+bool Dialect::restrictLanguage(const Dialect &l2)
+{
+    if (*this == l2)
+        return true;
+    QList<Dialect> ll1 = companionLanguages();
+    QList<Dialect> ll2 = l2.companionLanguages();
+    bool i1 = ll1.contains(l2);
+    bool i2 = ll2.contains(*this);
+    if (i1 && i2) {
+        if (ll1.size() < ll2.size())
+            return true;
+        if (ll2.size() < ll1.size()) {
+            *this = l2;
+            return true;
+        }
+        if (m_dialect < l2.m_dialect)
+            return true;
+        *this = l2;
+        return true;
+    }
+    if (i1 && !i2) {
+        *this = l2;
+        return true;
+    }
+    if (i2 && !i1)
+        return true;
+    QList<Dialect> qmlLangs = Dialect(Qml).companionLanguages();
+    if (qmlLangs.contains(*this) && qmlLangs.contains(l2))
+        *this = Dialect::Qml;
+    *this = Dialect::AnyLanguage;
+    return false;
+}
+
+QList<Dialect> Dialect::companionLanguages() const
+{
+    QList<Dialect> langs;
+    langs << *this;
+    switch (m_dialect) {
+    case Dialect::JavaScript:
+    case Dialect::Json:
+    case Dialect::QmlProject:
+    case Dialect::QmlTypeInfo:
+        break;
+    case Dialect::QmlQbs:
+        langs << Dialect::JavaScript;
+        break;
+    case Dialect::Qml:
+        langs << Dialect::QmlQtQuick1 << Dialect::QmlQtQuick2 << Dialect::JavaScript;
+        break;
+    case Dialect::QmlQtQuick1:
+    case Dialect::QmlQtQuick2:
+        langs << Dialect::Qml << Dialect::JavaScript;
+        break;
+    case Dialect::AnyLanguage:
+        langs << Dialect::JavaScript << Dialect::Json << Dialect::QmlProject << Dialect:: QmlQbs
+              << Dialect::QmlTypeInfo << Dialect::QmlQtQuick1 << Dialect::QmlQtQuick2
+              << Dialect::Qml;
+        break;
+    case Dialect::NoLanguage:
+        return QList<Dialect>(); // return at least itself?
+    }
+    if (*this != Dialect::AnyLanguage)
+        langs << Dialect::AnyLanguage;
+    return langs;
+}
+
+uint qHash(const Dialect &o)
+{
+    return uint(o.dialect());
+}
+
+QDebug operator << (QDebug &dbg, const Dialect &dialect)
+{
+    dbg << dialect.toString();
+    return dbg;
+}
+
+PathAndLanguage::PathAndLanguage(const Utils::FileName &path, Dialect language)
+    : m_path(path), m_language(language)
+{ }
+
+bool PathAndLanguage::operator ==(const PathAndLanguage &other) const
+{
+    return path() == other.path() && language() == other.language();
+}
+
+bool PathAndLanguage::operator <(const PathAndLanguage &other) const
+{
+    if (path() < other.path())
+        return true;
+    if (path() > other.path())
+        return false;
+    if (language() == other.language())
+        return false;
+    bool i1 = other.language().companionLanguages().contains(language());
+    bool i2 = language().companionLanguages().contains(other.language());
+    if (i1 && !i2)
+        return true;
+    if (i2 && !i1)
+        return false;
+    return language() < other.language();
+}
+
+QDebug operator << (QDebug &dbg, const PathAndLanguage &pathAndLanguage)
+{
+    dbg << "{ path:" << pathAndLanguage.path() << " language:" << pathAndLanguage.language().toString() << "}";
+    return dbg;
+}
+
+bool PathsAndLanguages::maybeInsert(const PathAndLanguage &pathAndLanguage) {
+    for (int i = 0; i < m_list.size(); ++i) {
+        PathAndLanguage currentElement = m_list.at(i);
+        if (currentElement.path() == pathAndLanguage.path()) {
+            int j = i;
+            do {
+                if (pathAndLanguage.language() < currentElement.language()) {
+                    if (currentElement.language() == pathAndLanguage.language())
+                        return false;
+                    break;
+                }
+                ++j;
+                if (j == m_list.length())
+                    break;
+                currentElement = m_list.at(j);
+            } while (currentElement.path() == pathAndLanguage.path());
+            m_list.insert(j, pathAndLanguage);
+            return true;
+        }
+    }
+    m_list.append(pathAndLanguage);
+    return true;
+}
+
+void PathsAndLanguages::compact() {
+    int oldCompactionPlace = 0;
+    Utils::FileName oldPath = m_list.first().path();
+    QList<PathAndLanguage> compactedList;
+    bool restrictFailed = false;
+    for (int i = 1; i < m_list.length(); ++i) {
+        Utils::FileName newPath = m_list.at(i).path();
+        if (newPath == oldPath) {
+            int newCompactionPlace = i - 1;
+            compactedList << m_list.mid(oldCompactionPlace, newCompactionPlace - oldCompactionPlace);
+            LanguageMerger merger;
+            merger.merge(m_list.at(i - 1).language());
+            do {
+                merger.merge(m_list.at(i++).language());
+                if (++i == m_list.length())
+                    break;
+                newPath = m_list.at(i).path();
+            } while (newPath == oldPath);
+            oldCompactionPlace = i;
+            compactedList << PathAndLanguage(oldPath, merger.mergedLanguage());
+            if (merger.restrictFailed())
+                restrictFailed = true;
+        }
+        oldPath = newPath;
+    }
+    if (oldCompactionPlace == 0)
+        return;
+    if (restrictFailed)
+        qCWarning(qmljsLog) << "failed to restrict PathAndLanguages " << m_list;
+    m_list = compactedList;
+}
+
+void LanguageMerger::merge(Dialect l)
+{
+    bool restrictSuccedeed = m_specificLanguage.restrictLanguage(l);
+    m_specificLanguage.mergeLanguage(m_minimalSpecificLanguage);
+    if (!restrictSuccedeed) {
+        m_minimalSpecificLanguage = m_specificLanguage;
+        m_restrictFailed = true;
+    }
+}
+
+} // namespace QmlJS
diff --git a/src/libs/qmljs/qmljsdialect.h b/src/libs/qmljs/qmljsdialect.h
new file mode 100644
index 0000000000..3ee6f26c12
--- /dev/null
+++ b/src/libs/qmljs/qmljsdialect.h
@@ -0,0 +1,174 @@
+/****************************************************************************
+**
+** Copyright (C) 2014 Digia Plc and/or its subsidiary(-ies).
+** Contact: http://www.qt-project.org/legal
+**
+** This file is part of Qt Creator.
+**
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and Digia.  For licensing terms and
+** conditions see http://qt.digia.com/licensing.  For further information
+** use the contact form at http://qt.digia.com/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Digia gives you certain additional
+** rights.  These rights are described in the Digia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+****************************************************************************/
+
+#ifndef QMLJSDIALECT_H
+#define QMLJSDIALECT_H
+
+#include "qmljsconstants.h"
+
+#include <utils/fileutils.h>
+
+#include <QString>
+
+namespace QmlJS {
+
+class QMLJS_EXPORT Dialect {
+public:
+    enum Enum
+    {
+        NoLanguage = 0,
+        JavaScript = 1,
+        Json = 2,
+        Qml = 3,
+        QmlQtQuick1 = 4,
+        QmlQtQuick2 = 5,
+        QmlQbs = 6,
+        QmlProject = 7,
+        QmlTypeInfo = 8,
+        AnyLanguage = 9,
+    };
+    Dialect(Enum dialect = NoLanguage)
+        : m_dialect(dialect)
+    { }
+    static Dialect mergeLanguages(const Dialect &l1, const Dialect &l2);
+
+    bool isQmlLikeLanguage() const;
+    bool isFullySupportedLanguage() const;
+    bool isQmlLikeOrJsLanguage() const;
+    QList<Dialect> companionLanguages() const;
+    bool restrictLanguage(const Dialect &l2);
+    QString toString() const;
+    bool operator ==(const Dialect &o) const;
+    bool operator !=(const Dialect &o) const {
+        return !(*this == o);
+    }
+    bool operator <(const Dialect &o) const;
+    Enum dialect() const {
+        return m_dialect;
+    }
+    void mergeLanguage(const Dialect &l2);
+private:
+    Enum m_dialect;
+};
+
+QMLJS_EXPORT uint qHash(const Dialect &o);
+
+QMLJS_EXPORT QDebug operator << (QDebug &dbg, const Dialect &dialect);
+
+class QMLJS_EXPORT PathAndLanguage {
+public:
+    PathAndLanguage(const Utils::FileName &path = Utils::FileName(), Dialect language = Dialect::AnyLanguage);
+    PathAndLanguage(const PathAndLanguage &o)
+        : m_path(o.path()), m_language(o.language())
+    { }
+    Utils::FileName path() const {
+        return m_path;
+    }
+    Dialect language() const {
+        return m_language;
+    }
+    bool operator ==(const PathAndLanguage &other) const;
+    bool operator < (const PathAndLanguage &other) const;
+private:
+    Utils::FileName m_path;
+    Dialect m_language;
+};
+
+// tries to find the "most specific" language still compatible with all requested ones
+class QMLJS_EXPORT LanguageMerger
+{
+public:
+    LanguageMerger()
+        : m_specificLanguage(Dialect::AnyLanguage),
+          m_minimalSpecificLanguage(Dialect::NoLanguage),
+          m_restrictFailed(false)
+    { }
+
+    void merge(Dialect l);
+
+    Dialect mergedLanguage() const {
+        return m_specificLanguage;
+    }
+    bool restrictFailed() const {
+        return m_restrictFailed;
+    }
+private:
+    Dialect m_specificLanguage;
+    Dialect m_minimalSpecificLanguage;
+    bool m_restrictFailed;
+};
+
+
+QMLJS_EXPORT QDebug operator << (QDebug &dbg, const PathAndLanguage &pathAndLanguage);
+
+class QMLJS_EXPORT PathsAndLanguages
+{
+public:
+    explicit PathsAndLanguages()
+    { }
+    explicit PathsAndLanguages(const QList<PathAndLanguage> &list)
+        : m_list(list)
+    { }
+    PathsAndLanguages(const PathsAndLanguages &o)
+        : m_list(o.m_list)
+    { }
+
+    bool maybeInsert(const Utils::FileName &path, Dialect language = Dialect::AnyLanguage) {
+        return maybeInsert(PathAndLanguage(path, language));
+    }
+
+    bool maybeInsert(const PathAndLanguage &pathAndLanguage);
+
+    PathAndLanguage at(int i) const {
+        return m_list.at(i);
+    }
+    int size() const {
+        return m_list.size();
+    }
+    int length() const {
+        return m_list.length();
+    }
+    void clear() {
+        m_list.clear();
+    }
+    // foreach support
+    typedef QList<PathAndLanguage>::const_iterator const_iterator;
+    const_iterator begin() const {
+        return m_list.begin();
+    }
+    const_iterator end() const {
+        return m_list.end();
+    }
+    void compact();
+private:
+    QList<PathAndLanguage> m_list;
+};
+
+} // namespace QmlJS
+#endif // QMLJSDIALECT_H
diff --git a/src/libs/qmljs/qmljsdocument.cpp b/src/libs/qmljs/qmljsdocument.cpp
index cf7fd70bd1..4987dd1a25 100644
--- a/src/libs/qmljs/qmljsdocument.cpp
+++ b/src/libs/qmljs/qmljsdocument.cpp
@@ -88,93 +88,7 @@ using namespace QmlJS::AST;
     threads finish and new information becomes available.
 */
 
-
-bool Document::isQmlLikeLanguage(Language::Enum language)
-{
-    switch (language) {
-    case Language::Qml:
-    case Language::QmlQtQuick1:
-    case Language::QmlQtQuick2:
-    case Language::QmlQbs:
-    case Language::QmlProject:
-    case Language::QmlTypeInfo:
-    case Language::AnyLanguage:
-        return true;
-    default:
-        return false;
-    }
-}
-
-bool Document::isFullySupportedLanguage(Language::Enum language)
-{
-    switch (language) {
-    case Language::JavaScript:
-    case Language::Json:
-    case Language::Qml:
-    case Language::QmlQtQuick1:
-    case Language::QmlQtQuick2:
-        return true;
-    case Language::NoLanguage:
-    case Language::AnyLanguage:
-    case Language::QmlQbs:
-    case Language::QmlProject:
-    case Language::QmlTypeInfo:
-        break;
-    }
-    return false;
-}
-
-bool Document::isQmlLikeOrJsLanguage(Language::Enum language)
-{
-    switch (language) {
-    case Language::Qml:
-    case Language::QmlQtQuick1:
-    case Language::QmlQtQuick2:
-    case Language::QmlQbs:
-    case Language::QmlProject:
-    case Language::QmlTypeInfo:
-    case Language::JavaScript:
-    case Language::AnyLanguage:
-        return true;
-    default:
-        return false;
-    }
-}
-
-QList<Language::Enum> Document::companionLanguages(Language::Enum language)
-{
-    QList<Language::Enum> langs;
-    langs << language;
-    switch (language) {
-    case Language::JavaScript:
-    case Language::Json:
-    case Language::QmlProject:
-    case Language::QmlTypeInfo:
-        break;
-    case Language::QmlQbs:
-        langs << Language::JavaScript;
-        break;
-    case Language::Qml:
-        langs << Language::QmlQtQuick1 << Language::QmlQtQuick2 << Language::JavaScript;
-        break;
-    case Language::QmlQtQuick1:
-    case Language::QmlQtQuick2:
-        langs << Language::Qml << Language::JavaScript;
-        break;
-    case Language::AnyLanguage:
-        langs << Language::JavaScript << Language::Json << Language::QmlProject << Language:: QmlQbs
-              << Language::QmlTypeInfo << Language::QmlQtQuick1 << Language::QmlQtQuick2
-              << Language::Qml;
-        break;
-    case Language::NoLanguage:
-        return QList<Language::Enum>(); // return at least itself?
-    }
-    if (language != Language::AnyLanguage)
-        langs << Language::AnyLanguage;
-    return langs;
-}
-
-Document::Document(const QString &fileName, Language::Enum language)
+Document::Document(const QString &fileName, Dialect language)
     : _engine(0)
     , _ast(0)
     , _bind(0)
@@ -186,7 +100,7 @@ Document::Document(const QString &fileName, Language::Enum language)
     QFileInfo fileInfo(fileName);
     _path = QDir::cleanPath(fileInfo.absolutePath());
 
-    if (isQmlLikeLanguage(language)) {
+    if (language.isQmlLikeLanguage()) {
         _componentName = fileInfo.baseName();
 
         if (! _componentName.isEmpty()) {
@@ -207,7 +121,7 @@ Document::~Document()
         delete _engine;
 }
 
-Document::MutablePtr Document::create(const QString &fileName, Language::Enum language)
+Document::MutablePtr Document::create(const QString &fileName, Dialect language)
 {
     Document::MutablePtr doc(new Document(fileName, language));
     doc->_ptr = doc;
@@ -221,15 +135,15 @@ Document::Ptr Document::ptr() const
 
 bool Document::isQmlDocument() const
 {
-    return isQmlLikeLanguage(_language);
+    return _language.isQmlLikeLanguage();
 }
 
-Language::Enum Document::language() const
+Dialect Document::language() const
 {
     return _language;
 }
 
-void Document::setLanguage(Language::Enum l)
+void Document::setLanguage(Dialect l)
 {
     _language = l;
 }
@@ -357,7 +271,7 @@ bool Document::parse_helper(int startToken)
     Parser parser(_engine);
 
     QString source = _source;
-    lexer.setCode(source, /*line = */ 1, /*qmlMode = */isQmlLikeLanguage(_language));
+    lexer.setCode(source, /*line = */ 1, /*qmlMode = */_language.isQmlLikeLanguage());
 
     CollectDirectives collectDirectives(path());
     _engine->setDirectives(&collectDirectives);
@@ -539,7 +453,7 @@ void Snapshot::insertLibraryInfo(const QString &path, const LibraryInfo &info)
     if (!info.wasFound()) return;
     CoreImport cImport;
     cImport.importId = path;
-    cImport.language = Language::AnyLanguage;
+    cImport.language = Dialect::AnyLanguage;
     QSet<ImportKey> packages;
     foreach (const ModuleApiInfo &moduleInfo, info.moduleApis()) {
         ImportKey iKey(ImportType::Library, moduleInfo.uri, moduleInfo.version.majorVersion(),
@@ -638,7 +552,7 @@ QmlJS::ImportDependencies *Snapshot::importDependencies()
 
 Document::MutablePtr Snapshot::documentFromSource(
         const QString &code, const QString &fileName,
-        Language::Enum language) const
+        Dialect language) const
 {
     Document::MutablePtr newDoc = Document::create(fileName, language);
 
diff --git a/src/libs/qmljs/qmljsdocument.h b/src/libs/qmljs/qmljsdocument.h
index 1a0a331de9..9a02be006b 100644
--- a/src/libs/qmljs/qmljsdocument.h
+++ b/src/libs/qmljs/qmljsdocument.h
@@ -35,6 +35,7 @@
 
 #include <languageutils/fakemetaobject.h>
 
+#include "qmljsdialect.h"
 #include "parser/qmldirparser_p.h"
 #include "parser/qmljsengine_p.h"
 #include "qmljs_global.h"
@@ -52,24 +53,19 @@ class QMLJS_EXPORT Document
 public:
     typedef QSharedPointer<const Document> Ptr;
     typedef QSharedPointer<Document> MutablePtr;
-
-    static bool isQmlLikeLanguage(Language::Enum languge);
-    static bool isFullySupportedLanguage(Language::Enum language);
-    static bool isQmlLikeOrJsLanguage(Language::Enum language);
-    static QList<Language::Enum> companionLanguages(Language::Enum language);
 protected:
-    Document(const QString &fileName, Language::Enum language);
+    Document(const QString &fileName, Dialect language);
 
 public:
     ~Document();
 
-    static MutablePtr create(const QString &fileName, Language::Enum language);
+    static MutablePtr create(const QString &fileName, Dialect language);
 
     Document::Ptr ptr() const;
 
     bool isQmlDocument() const;
-    Language::Enum language() const;
-    void setLanguage(Language::Enum l);
+    Dialect language() const;
+    void setLanguage(Dialect l);
 
     QString importId() const;
     QByteArray fingerprint() const;
@@ -117,7 +113,7 @@ private:
     QWeakPointer<Document> _ptr;
     QByteArray _fingerprint;
     int _editorRevision;
-    Language::Enum _language;
+    Dialect _language;
     bool _parsedCorrectly;
 
     // for documentFromSource
@@ -246,7 +242,7 @@ public:
 
     Document::MutablePtr documentFromSource(const QString &code,
                                      const QString &fileName,
-                                     Language::Enum language) const;
+                                     Dialect language) const;
 };
 
 } // namespace QmlJS
diff --git a/src/libs/qmljs/qmljsimportdependencies.cpp b/src/libs/qmljs/qmljsimportdependencies.cpp
index dd3e2e70b8..4b39016c94 100644
--- a/src/libs/qmljs/qmljsimportdependencies.cpp
+++ b/src/libs/qmljs/qmljsimportdependencies.cpp
@@ -509,10 +509,10 @@ bool operator !=(const Export &i1, const Export &i2)
     return !(i1 == i2);
 }
 
-CoreImport::CoreImport() : language(Language::Qml) { }
+CoreImport::CoreImport() : language(Dialect::Qml) { }
 
 CoreImport::CoreImport(const QString &importId, const QList<Export> &possibleExports,
-                       Language::Enum language, const QByteArray &fingerprint)
+                       Dialect language, const QByteArray &fingerprint)
     : importId(importId), possibleExports(possibleExports), language(language),
       fingerprint(fingerprint)
 { }
@@ -787,7 +787,7 @@ void ImportDependencies::addExport(const QString &importId, const ImportKey &imp
 {
     if (!m_coreImports.contains(importId)) {
         CoreImport newImport(importId);
-        newImport.language = Language::AnyLanguage;
+        newImport.language = Dialect::AnyLanguage;
         newImport.possibleExports.append(Export(importKey, requiredPath, false, typeName));
         m_coreImports.insert(newImport.importId, newImport);
         m_importCache[importKey].append(importId);
diff --git a/src/libs/qmljs/qmljsimportdependencies.h b/src/libs/qmljs/qmljsimportdependencies.h
index 8a412b754e..cabd0df9af 100644
--- a/src/libs/qmljs/qmljsimportdependencies.h
+++ b/src/libs/qmljs/qmljsimportdependencies.h
@@ -31,6 +31,7 @@
 #define QMLJSIMPORTCACHE_H
 
 #include "qmljsviewercontext.h"
+#include "qmljsdialect.h"
 
 #include <languageutils/componentversion.h>
 #include <utils/qtcoverride.h>
@@ -147,10 +148,10 @@ class QMLJS_EXPORT CoreImport
 public:
     CoreImport();
     CoreImport(const QString &importId, const QList<Export> &possibleExports = QList<Export>(),
-               Language::Enum language = Language::Qml, const QByteArray &fingerprint = QByteArray());
+               Dialect language = Dialect::Qml, const QByteArray &fingerprint = QByteArray());
     QString importId;
     QList<Export> possibleExports;
-    Language::Enum language;
+    Dialect language;
     QByteArray fingerprint;
     bool valid();
 };
diff --git a/src/libs/qmljs/qmljslink.cpp b/src/libs/qmljs/qmljslink.cpp
index e0006e4b83..76379ed3d7 100644
--- a/src/libs/qmljs/qmljslink.cpp
+++ b/src/libs/qmljs/qmljslink.cpp
@@ -333,7 +333,7 @@ Import LinkPrivate::importFileOrDirectory(Document::Ptr doc, const ImportInfo &i
                                                ->filesInQrcPath(path));
         while (iter.hasNext()) {
             iter.next();
-            if (Document::isQmlLikeLanguage(ModelManagerInterface::guessLanguageOfFile(iter.key()))) {
+            if (ModelManagerInterface::guessLanguageOfFile(iter.key()).isQmlLikeLanguage()) {
                 Document::Ptr importedDoc = snapshot.document(iter.value().at(0));
                 if (importedDoc && importedDoc->bind()->rootObjectValue()) {
                     const QString targetName = QFileInfo(iter.key()).baseName();
diff --git a/src/libs/qmljs/qmljsmodelmanagerinterface.cpp b/src/libs/qmljs/qmljsmodelmanagerinterface.cpp
index 396bc90f3a..eb72166154 100644
--- a/src/libs/qmljs/qmljsmodelmanagerinterface.cpp
+++ b/src/libs/qmljs/qmljsmodelmanagerinterface.cpp
@@ -34,6 +34,7 @@
 #include "qmljsmodelmanagerinterface.h"
 #include "qmljsplugindumper.h"
 #include "qmljstypedescriptionreader.h"
+#include "qmljsdialect.h"
 
 #include <cplusplus/cppmodelmanagerbase.h>
 #include <utils/hostosinfo.h>
@@ -113,6 +114,9 @@ ModelManagerInterface::ModelManagerInterface(QObject *parent)
 
     qRegisterMetaType<QmlJS::Document::Ptr>("QmlJS::Document::Ptr");
     qRegisterMetaType<QmlJS::LibraryInfo>("QmlJS::LibraryInfo");
+    qRegisterMetaType<QmlJS::Dialect>("QmlJS::Dialect");
+    qRegisterMetaType<QmlJS::PathAndLanguage>("QmlJS::PathAndLanguage");
+    qRegisterMetaType<QmlJS::PathsAndLanguages>("QmlJS::PathsAndLanguages");
 
     m_defaultProjectInfo.qtImportsPath = QLibraryInfo::location(QLibraryInfo::ImportsPath);
 #if (QT_VERSION >= QT_VERSION_CHECK(5, 0, 0))
@@ -134,39 +138,39 @@ ModelManagerInterface::~ModelManagerInterface()
     g_instance = 0;
 }
 
-static QHash<QString, Language::Enum> defaultLanguageMapping()
+static QHash<QString, Dialect> defaultLanguageMapping()
 {
-    QHash<QString, Language::Enum> res;
-    res[QLatin1String("js")] = Language::JavaScript;
-    res[QLatin1String("qml")] = Language::Qml;
-    res[QLatin1String("qmltypes")] = Language::QmlTypeInfo;
-    res[QLatin1String("qmlproject")] = Language::QmlProject;
-    res[QLatin1String("json")] = Language::Json;
-    res[QLatin1String("qbs")] = Language::QmlQbs;
+    QHash<QString, Dialect> res;
+    res[QLatin1String("js")] = Dialect::JavaScript;
+    res[QLatin1String("qml")] = Dialect::Qml;
+    res[QLatin1String("qmltypes")] = Dialect::QmlTypeInfo;
+    res[QLatin1String("qmlproject")] = Dialect::QmlProject;
+    res[QLatin1String("json")] = Dialect::Json;
+    res[QLatin1String("qbs")] = Dialect::QmlQbs;
     return res;
 }
 
-Language::Enum ModelManagerInterface::guessLanguageOfFile(const QString &fileName)
+Dialect ModelManagerInterface::guessLanguageOfFile(const QString &fileName)
 {
-    QHash<QString, Language::Enum> lMapping;
+    QHash<QString, Dialect> lMapping;
     if (instance())
         lMapping = instance()->languageForSuffix();
     else
         lMapping = defaultLanguageMapping();
     const QFileInfo info(fileName);
     const QString fileSuffix = info.suffix();
-    return lMapping.value(fileSuffix, Language::NoLanguage);
+    return lMapping.value(fileSuffix, Dialect::NoLanguage);
 }
 
-QStringList ModelManagerInterface::globPatternsForLanguages(const QList<Language::Enum> languages)
+QStringList ModelManagerInterface::globPatternsForLanguages(const QList<Dialect> languages)
 {
-    QHash<QString, Language::Enum> lMapping;
+    QHash<QString, Dialect> lMapping;
     if (instance())
         lMapping = instance()->languageForSuffix();
     else
         lMapping = defaultLanguageMapping();
     QStringList patterns;
-    QHashIterator<QString,Language::Enum> i(lMapping);
+    QHashIterator<QString,Dialect> i(lMapping);
     while (i.hasNext()) {
         i.next();
         if (languages.contains(i.value()))
@@ -203,7 +207,7 @@ void ModelManagerInterface::activateScan()
     }
 }
 
-QHash<QString, Language::Enum> ModelManagerInterface::languageForSuffix() const
+QHash<QString, Dialect> ModelManagerInterface::languageForSuffix() const
 {
     return defaultLanguageMapping();
 }
@@ -294,7 +298,7 @@ QFuture<void> ModelManagerInterface::refreshSourceFiles(const QStringList &sourc
 
     QFuture<void> result = QtConcurrent::run(&ModelManagerInterface::parse,
                                               workingCopyInternal(), sourceFiles,
-                                              this, Language::Qml,
+                                              this, Dialect(Dialect::Qml),
                                               emitDocumentOnDiskChanged);
 
     if (m_synchronizer.futures().size() > 10) {
@@ -334,7 +338,7 @@ void ModelManagerInterface::fileChangedOnDisk(const QString &path)
 {
     QtConcurrent::run(&ModelManagerInterface::parse,
                       workingCopyInternal(), QStringList() << path,
-                      this, Language::AnyLanguage, true);
+                      this, Dialect(Dialect::AnyLanguage), true);
 }
 
 void ModelManagerInterface::removeFiles(const QStringList &files)
@@ -394,8 +398,8 @@ bool pInfoLessThanImports(const ModelManagerInterface::ProjectInfo &p1, const Mo
         return true;
     if (p1.qtImportsPath > p2.qtImportsPath)
         return false;
-    QStringList s1 = p1.importPaths;
-    QStringList s2 = p2.importPaths;
+    const PathsAndLanguages &s1 = p1.importPaths;
+    const PathsAndLanguages &s2 = p2.importPaths;
     if (s1.size() < s2.size())
         return true;
     if (s1.size() > s2.size())
@@ -403,7 +407,7 @@ bool pInfoLessThanImports(const ModelManagerInterface::ProjectInfo &p1, const Mo
     for (int i = 0; i < s1.size(); ++i) {
         if (s1.at(i) < s2.at(i))
             return true;
-        else if (s1.at(i) > s2.at(i))
+        else if (s2.at(i) < s1.at(i))
             return false;
     }
     return false;
@@ -603,9 +607,8 @@ ModelManagerInterface::ProjectInfo ModelManagerInterface::projectInfoForPath(QSt
             res.qtImportsPath = pInfo.qtImportsPath;
         if (res.qtQmlPath.isEmpty())
             res.qtQmlPath = pInfo.qtQmlPath;
-        foreach (const QString &path, pInfo.importPaths)
-            if (!res.importPaths.contains(path))
-                res.importPaths.append(path);
+        for (int i = 0; i < pInfo.importPaths.size(); ++i)
+            res.importPaths.maybeInsert(pInfo.importPaths.at(i));
     }
     return res;
 }
@@ -643,7 +646,7 @@ void ModelManagerInterface::updateLibraryInfo(const QString &path, const Library
         emit libraryInfoUpdated(path, info);
 }
 
-static QStringList filesInDirectoryForLanguages(const QString &path, QList<Language::Enum> languages)
+static QStringList filesInDirectoryForLanguages(const QString &path, QList<Dialect> languages)
 {
     const QStringList pattern = ModelManagerInterface::globPatternsForLanguages(languages);
     QStringList files;
@@ -663,7 +666,7 @@ static void findNewImplicitImports(const Document::Ptr &doc, const Snapshot &sna
     if (snapshot.documentsInDirectory(doc->path()).isEmpty()) {
         if (! scannedPaths->contains(doc->path())) {
             *importedFiles += filesInDirectoryForLanguages(doc->path(),
-                                                  Document::companionLanguages(doc->language()));
+                                                  doc->language().companionLanguages());
             scannedPaths->insert(doc->path());
         }
     }
@@ -682,7 +685,7 @@ static void findNewFileImports(const Document::Ptr &doc, const Snapshot &snapsho
             if (snapshot.documentsInDirectory(importName).isEmpty()) {
                 if (! scannedPaths->contains(importName)) {
                     *importedFiles += filesInDirectoryForLanguages(importName,
-                                                          Document::companionLanguages(doc->language()));
+                                                          doc->language().companionLanguages());
                     scannedPaths->insert(importName);
                 }
             }
@@ -696,7 +699,7 @@ static void findNewFileImports(const Document::Ptr &doc, const Snapshot &snapsho
             QMapIterator<QString,QStringList> dirContents(ModelManagerInterface::instance()->filesInQrcPath(importName));
             while (dirContents.hasNext()) {
                 dirContents.next();
-                if (Document::isQmlLikeOrJsLanguage(ModelManagerInterface::guessLanguageOfFile(dirContents.key()))) {
+                if (ModelManagerInterface::guessLanguageOfFile(dirContents.key()).isQmlLikeOrJsLanguage()) {
                     foreach (const QString &filePath, dirContents.value()) {
                         if (! snapshot.document(filePath))
                             *importedFiles += filePath;
@@ -759,7 +762,7 @@ static bool findNewQmlLibraryInPath(const QString &path,
             const QString path = QDir::cleanPath(componentFileInfo.absolutePath());
             if (! scannedPaths->contains(path)) {
                 *importedFiles += filesInDirectoryForLanguages(path,
-                                                      Document::companionLanguages(Language::AnyLanguage));
+                     Dialect(Dialect::AnyLanguage).companionLanguages());
                 scannedPaths->insert(path);
             }
         }
@@ -806,7 +809,7 @@ static void findNewLibraryImports(const Document::Ptr &doc, const Snapshot &snap
                             importedFiles, scannedPaths, newLibraries, false);
 
     // scan dir and lib imports
-    const QStringList importPaths = modelManager->importPaths();
+    const PathsAndLanguages importPaths = modelManager->importPaths();
     foreach (const ImportInfo &import, doc->bind()->imports()) {
         if (import.type() == ImportType::Directory) {
             const QString targetPath = import.path();
@@ -817,8 +820,8 @@ static void findNewLibraryImports(const Document::Ptr &doc, const Snapshot &snap
         if (import.type() == ImportType::Library) {
             if (!import.version().isValid())
                 continue;
-            foreach (const QString &importPath, importPaths) {
-                const QString targetPath = QDir(importPath).filePath(import.path());
+            foreach (const PathAndLanguage &importPath, importPaths) {
+                const QString targetPath = importPath.path().toFileInfo().dir().filePath(import.path());
                 findNewQmlLibrary(targetPath, import.version(), snapshot, modelManager,
                                   importedFiles, scannedPaths, newLibraries);
             }
@@ -831,7 +834,7 @@ void ModelManagerInterface::parseLoop(QSet<QString> &scannedPaths,
                              WorkingCopy workingCopy,
                              QStringList files,
                              ModelManagerInterface *modelManager,
-                             Language::Enum mainLanguage,
+                             Dialect mainLanguage,
                              bool emitDocChangedOnDisk,
                              std::function<bool(qreal)> reportProgress)
 {
@@ -841,14 +844,14 @@ void ModelManagerInterface::parseLoop(QSet<QString> &scannedPaths,
 
         const QString fileName = files.at(i);
 
-        Language::Enum language = guessLanguageOfFile(fileName);
-        if (language == Language::NoLanguage) {
+        Dialect language = guessLanguageOfFile(fileName);
+        if (language == Dialect::NoLanguage) {
             if (fileName.endsWith(QLatin1String(".qrc")))
                 modelManager->updateQrcFile(fileName);
             continue;
         }
-        if (language == Language::Qml
-                && (mainLanguage == Language::QmlQtQuick1 || mainLanguage == Language::QmlQtQuick2))
+        if (language == Dialect::Qml
+                && (mainLanguage == Dialect::QmlQtQuick1 || mainLanguage == Dialect::QmlQtQuick2))
             language = mainLanguage;
         QString contents;
         int documentRevision = 0;
@@ -917,7 +920,7 @@ void ModelManagerInterface::parse(QFutureInterface<void> &future,
                          WorkingCopy workingCopy,
                          QStringList files,
                          ModelManagerInterface *modelManager,
-                         Language::Enum mainLanguage,
+                         Dialect mainLanguage,
                          bool emitDocChangedOnDisk)
 {
     FutureReporter reporter(future);
@@ -935,15 +938,15 @@ void ModelManagerInterface::parse(QFutureInterface<void> &future,
 struct ScanItem {
     QString path;
     int depth;
-    ScanItem(QString path = QString(), int depth = 0)
-        : path(path), depth(depth)
+    Dialect language;
+    ScanItem(QString path = QString(), int depth = 0, Dialect language = Dialect::AnyLanguage)
+        : path(path), depth(depth), language(language)
     { }
 };
 
 void ModelManagerInterface::importScan(QFutureInterface<void> &future,
                               ModelManagerInterface::WorkingCopy workingCopy,
-                              QStringList paths, ModelManagerInterface *modelManager,
-                              Language::Enum language,
+                              PathsAndLanguages paths, ModelManagerInterface *modelManager,
                               bool emitDocChangedOnDisk)
 {
     // paths we have scanned for files and added to the files list
@@ -959,11 +962,12 @@ void ModelManagerInterface::importScan(QFutureInterface<void> &future,
     pathsToScan.reserve(paths.size());
     {
         QMutexLocker l(&modelManager->m_mutex);
-        foreach (const QString &path, paths) {
-            QString cPath = QDir::cleanPath(path);
+        for (int i = 0; i < paths.size(); ++i) {
+            PathAndLanguage pAndL = paths.at(i);
+            QString cPath = QDir::cleanPath(pAndL.path().toString());
             if (modelManager->m_scannedPaths.contains(cPath))
                 continue;
-            pathsToScan.append(ScanItem(cPath));
+            pathsToScan.append(ScanItem(cPath, 0, pAndL.language()));
             modelManager->m_scannedPaths.insert(cPath);
         }
     }
@@ -983,14 +987,14 @@ void ModelManagerInterface::importScan(QFutureInterface<void> &future,
                                          &scannedPaths, &newLibraries, true)
                     && !libOnly && snapshot.documentsInDirectory(toScan.path).isEmpty())
                 importedFiles += filesInDirectoryForLanguages(toScan.path,
-                                                     Document::companionLanguages(language));
+                                                     toScan.language.companionLanguages());
             workDone += 1;
             future.setProgressValue(progressRange * workDone / totalWork);
             if (!importedFiles.isEmpty()) {
                 FutureReporter reporter(future, progressRange * pathBudget / (4 * totalWork),
                                         progressRange * workDone / totalWork);
                 parseLoop(scannedPaths, newLibraries, workingCopy, importedFiles, modelManager,
-                          language, emitDocChangedOnDisk, reporter); // run in parallel??
+                          toScan.language, emitDocChangedOnDisk, reporter); // run in parallel??
                 importedFiles.clear();
             }
             workDone += pathBudget / 4 - 1;
@@ -1004,8 +1008,8 @@ void ModelManagerInterface::importScan(QFutureInterface<void> &future,
             QStringList subDirs(dir.entryList(QDir::Dirs | QDir::NoDotAndDotDot));
             workDone += 1;
             totalWork += pathBudget / 2 * subDirs.size() - pathBudget * 3 / 4 + 1;
-            foreach (const QString &path, subDirs)
-                pathsToScan.append(ScanItem(dir.absoluteFilePath(path), toScan.depth + 1));
+            foreach (const QString path, subDirs)
+                pathsToScan.append(ScanItem(dir.absoluteFilePath(path), toScan.depth + 1, toScan.language));
         } else {
             workDone += pathBudget * 3 / 4;
         }
@@ -1015,12 +1019,12 @@ void ModelManagerInterface::importScan(QFutureInterface<void> &future,
     if (future.isCanceled()) {
         // assume no work has been done
         QMutexLocker l(&modelManager->m_mutex);
-        foreach (const QString &path, paths)
-            modelManager->m_scannedPaths.remove(path);
+        for (int i = 0; i < paths.size(); ++i)
+            modelManager->m_scannedPaths.remove(paths.at(i).path().toString());
     }
 }
 
-QStringList ModelManagerInterface::importPaths() const
+PathsAndLanguages ModelManagerInterface::importPaths() const
 {
     QMutexLocker l(&m_mutex);
     return m_allImportPaths;
@@ -1038,23 +1042,20 @@ QmlLanguageBundles ModelManagerInterface::extendedBundles() const
     return m_extendedBundles;
 }
 
-void ModelManagerInterface::maybeScan(const QStringList &importPaths,
-                                      Language::Enum defaultLanguage)
+void ModelManagerInterface::maybeScan(const PathsAndLanguages &importPaths)
 {
-    QStringList pathToScan;
+    PathsAndLanguages pathToScan;
     {
         QMutexLocker l(&m_mutex);
-        foreach (const QString &importPath, importPaths)
-            if (!m_scannedPaths.contains(importPath)) {
-                pathToScan.append(importPath);
-            }
+        foreach (const PathAndLanguage &importPath, importPaths)
+            if (!m_scannedPaths.contains(importPath.path().toString()))
+                pathToScan.maybeInsert(importPath);
     }
 
-    if (pathToScan.count() > 1) {
+    if (pathToScan.length() > 1) {
         QFuture<void> result = QtConcurrent::run(&ModelManagerInterface::importScan,
                                                   workingCopyInternal(), pathToScan,
-                                                  this, defaultLanguage,
-                                                  true);
+                                                  this, true);
 
         if (m_synchronizer.futures().size() > 10) {
             QList<QFuture<void> > futures = m_synchronizer.futures();
@@ -1075,33 +1076,37 @@ void ModelManagerInterface::maybeScan(const QStringList &importPaths,
 
 void ModelManagerInterface::updateImportPaths()
 {
-    QStringList allImportPaths;
+    PathsAndLanguages allImportPaths;
     QmlLanguageBundles activeBundles;
     QmlLanguageBundles extendedBundles;
     QMapIterator<ProjectExplorer::Project *, ProjectInfo> pInfoIter(m_projects);
-    QHashIterator<Language::Enum, QmlJS::ViewerContext> vCtxsIter = m_defaultVContexts;
+    QHashIterator<Dialect, QmlJS::ViewerContext> vCtxsIter = m_defaultVContexts;
     while (pInfoIter.hasNext()) {
         pInfoIter.next();
-        foreach (const QString &path, pInfoIter.value().importPaths) {
-            const QString canonicalPath = QFileInfo(path).canonicalFilePath();
+        const PathsAndLanguages &iPaths = pInfoIter.value().importPaths;
+        for (int i = 0; i < iPaths.size(); ++i) {
+            PathAndLanguage pAndL = iPaths.at(i);
+            const QString canonicalPath = pAndL.path().toFileInfo().canonicalFilePath();
             if (!canonicalPath.isEmpty())
-                allImportPaths += canonicalPath;
+                allImportPaths.maybeInsert(Utils::FileName::fromString(canonicalPath),
+                                           pAndL.language());
         }
     }
     while (vCtxsIter.hasNext()) {
         vCtxsIter.next();
-        allImportPaths << vCtxsIter.value().paths;
+        foreach (const QString &path, vCtxsIter.value().paths)
+            allImportPaths.maybeInsert(Utils::FileName::fromString(path), vCtxsIter.value().language);
     }
     pInfoIter.toFront();
     while (pInfoIter.hasNext()) {
         pInfoIter.next();
         activeBundles.mergeLanguageBundles(pInfoIter.value().activeBundle);
-        foreach (Language::Enum l, pInfoIter.value().activeBundle.languages()) {
+        foreach (Dialect l, pInfoIter.value().activeBundle.languages()) {
             foreach (const QString &path, pInfoIter.value().activeBundle.bundleForLanguage(l)
                  .searchPaths().stringList()) {
                 const QString canonicalPath = QFileInfo(path).canonicalFilePath();
                 if (!canonicalPath.isEmpty())
-                    allImportPaths += canonicalPath;
+                    allImportPaths.maybeInsert(Utils::FileName::fromString(canonicalPath), l);
             }
         }
     }
@@ -1109,28 +1114,29 @@ void ModelManagerInterface::updateImportPaths()
     while (pInfoIter.hasNext()) {
         pInfoIter.next();
         QString pathAtt = pInfoIter.value().qtQmlPath;
-        if (!pathAtt.isEmpty() && (allImportPaths.isEmpty() || allImportPaths.last() != pathAtt))
-            allImportPaths.append(pathAtt);
+        if (!pathAtt.isEmpty())
+            allImportPaths.maybeInsert(Utils::FileName::fromString(pathAtt), Dialect::QmlQtQuick2);
     }
     {
         QString pathAtt = defaultProjectInfo().qtQmlPath;
-        if (!pathAtt.isEmpty() && (allImportPaths.isEmpty() || allImportPaths.last() != pathAtt))
-            allImportPaths.append(pathAtt);
+        if (!pathAtt.isEmpty())
+            allImportPaths.maybeInsert(Utils::FileName::fromString(pathAtt), Dialect::QmlQtQuick2);
     }
     pInfoIter.toFront();
     while (pInfoIter.hasNext()) {
         pInfoIter.next();
         QString pathAtt = pInfoIter.value().qtImportsPath;
-        if (!pathAtt.isEmpty() && (allImportPaths.isEmpty() || allImportPaths.last() != pathAtt))
-            allImportPaths.append(pathAtt);
+        if (!pathAtt.isEmpty())
+            allImportPaths.maybeInsert(Utils::FileName::fromString(pathAtt), Dialect::QmlQtQuick1);
     }
     {
         QString pathAtt = defaultProjectInfo().qtImportsPath;
-        if (!pathAtt.isEmpty() && (allImportPaths.isEmpty() || allImportPaths.last() != pathAtt))
-            allImportPaths.append(pathAtt);
+        if (!pathAtt.isEmpty())
+            allImportPaths.maybeInsert(Utils::FileName::fromString(pathAtt), Dialect::QmlQtQuick1);
     }
-    allImportPaths += m_defaultImportPaths;
-    allImportPaths.removeDuplicates();
+    foreach (const QString &path, m_defaultImportPaths)
+        allImportPaths.maybeInsert(Utils::FileName::fromString(path), Dialect::Qml);
+    allImportPaths.compact();
 
     {
         QMutexLocker l(&m_mutex);
@@ -1152,7 +1158,7 @@ void ModelManagerInterface::updateImportPaths()
 
     if (!m_shouldScanImports)
         return;
-    maybeScan(allImportPaths, Language::Qml);
+    maybeScan(allImportPaths);
 }
 
 void ModelManagerInterface::loadPluginTypes(const QString &libraryPath, const QString &importPath,
@@ -1298,10 +1304,10 @@ ViewerContext ModelManagerInterface::completeVContext(const ViewerContext &vCtx,
     ViewerContext res = vCtx;
 
     if (!doc.isNull()
-            && ((vCtx.language == Language::AnyLanguage && doc->language() != Language::NoLanguage)
-                || (vCtx.language == Language::Qml
-                    && (doc->language() == Language::QmlQtQuick1
-                        || doc->language() == Language::QmlQtQuick2))))
+            && ((vCtx.language == Dialect::AnyLanguage && doc->language() != Dialect::NoLanguage)
+                || (vCtx.language == Dialect::Qml
+                    && (doc->language() == Dialect::QmlQtQuick1
+                        || doc->language() == Dialect::QmlQtQuick2))))
         res.language = doc->language();
     ProjectInfo info;
     if (!doc.isNull())
@@ -1322,17 +1328,17 @@ ViewerContext ModelManagerInterface::completeVContext(const ViewerContext &vCtx,
     {
         foreach (const QString &path, defaultVCtx.paths)
             res.maybeAddPath(path);
-        switch (res.language) {
-        case Language::AnyLanguage:
-        case Language::Qml:
+        switch (res.language.dialect()) {
+        case Dialect::AnyLanguage:
+        case Dialect::Qml:
             res.maybeAddPath(info.qtQmlPath);
             // fallthrough
-        case Language::QmlQtQuick1:
+        case Dialect::QmlQtQuick1:
             res.maybeAddPath(info.qtImportsPath);
             // fallthrough
-        case Language::QmlQtQuick2:
+        case Dialect::QmlQtQuick2:
         {
-            if (res.language == Language::QmlQtQuick2)
+            if (res.language == Dialect::QmlQtQuick2)
                 res.maybeAddPath(info.qtQmlPath);
             QList<ProjectInfo> allProjects;
             {
@@ -1340,18 +1346,22 @@ ViewerContext ModelManagerInterface::completeVContext(const ViewerContext &vCtx,
                 allProjects = m_projects.values();
             }
             std::sort(allProjects.begin(), allProjects.end(), &pInfoLessThanImports);
+            QList<Dialect> languages = res.language.companionLanguages();
             foreach (const ProjectInfo &pInfo, allProjects) {
-                foreach (const QString &path, pInfo.importPaths)
-                    res.maybeAddPath(path);
+                for (int i = 0; i< pInfo.importPaths.size(); ++i) {
+                    PathAndLanguage pAndL = pInfo.importPaths.at(i);
+                    if (languages.contains(pAndL.language()) || pAndL.language().companionLanguages().contains(res.language))
+                        res.maybeAddPath(pAndL.path().toString());
+                }
             }
             break;
         }
-        case Language::NoLanguage:
-        case Language::JavaScript:
-        case Language::QmlTypeInfo:
-        case Language::Json:
-        case Language::QmlQbs:
-        case Language::QmlProject:
+        case Dialect::NoLanguage:
+        case Dialect::JavaScript:
+        case Dialect::QmlTypeInfo:
+        case Dialect::Json:
+        case Dialect::QmlQbs:
+        case Dialect::QmlProject:
             break;
         }
         break;
@@ -1362,11 +1372,11 @@ ViewerContext ModelManagerInterface::completeVContext(const ViewerContext &vCtx,
     case ViewerContext::AddDefaultPaths:
         foreach (const QString &path, defaultVCtx.paths)
             res.maybeAddPath(path);
-        if (res.language == Language::AnyLanguage || res.language == Language::Qml
-                || res.language == Language::QmlQtQuick2)
+        if (res.language == Dialect::AnyLanguage || res.language == Dialect::Qml
+                || res.language == Dialect::QmlQtQuick2)
             res.maybeAddPath(info.qtImportsPath);
-        if (res.language == Language::AnyLanguage || res.language == Language::Qml
-                || res.language == Language::QmlQtQuick1)
+        if (res.language == Dialect::AnyLanguage || res.language == Dialect::Qml
+                || res.language == Dialect::QmlQtQuick1)
             res.maybeAddPath(info.qtQmlPath);
         break;
     }
@@ -1374,15 +1384,15 @@ ViewerContext ModelManagerInterface::completeVContext(const ViewerContext &vCtx,
     return res;
 }
 
-ViewerContext ModelManagerInterface::defaultVContext(Language::Enum language,
+ViewerContext ModelManagerInterface::defaultVContext(Dialect language,
                                                      const Document::Ptr &doc,
                                                      bool autoComplete) const
 {
     if (!doc.isNull()) {
-        if (language == Language::AnyLanguage && doc->language() != Language::NoLanguage)
+        if (language == Dialect::AnyLanguage && doc->language() != Dialect::NoLanguage)
             language = doc->language();
-        else if (language == Language::Qml &&
-                 (doc->language() == Language::QmlQtQuick1 || doc->language() == Language::QmlQtQuick2))
+        else if (language == Dialect::Qml &&
+                 (doc->language() == Dialect::QmlQtQuick1 || doc->language() == Dialect::QmlQtQuick2))
             language = doc->language();
     }
     ViewerContext defaultCtx;
@@ -1425,7 +1435,7 @@ Document::Ptr ModelManagerInterface::ensuredGetDocumentForPath(const QString &fi
 {
     QmlJS::Document::Ptr document = newestSnapshot().document(filePath);
     if (!document) {
-        document = QmlJS::Document::create(filePath, QmlJS::Language::Qml);
+        document = QmlJS::Document::create(filePath, QmlJS::Dialect::Qml);
         QMutexLocker lock(&m_mutex);
 
         m_newestSnapshot.insert(document);
diff --git a/src/libs/qmljs/qmljsmodelmanagerinterface.h b/src/libs/qmljs/qmljsmodelmanagerinterface.h
index 593fc83358..b1cac13837 100644
--- a/src/libs/qmljs/qmljsmodelmanagerinterface.h
+++ b/src/libs/qmljs/qmljsmodelmanagerinterface.h
@@ -36,9 +36,11 @@
 #include "qmljsdocument.h"
 #include "qmljsqrcparser.h"
 #include "qmljsviewercontext.h"
+#include "qmljsdialect.h"
 
 #include <cplusplus/CppDocument.h>
 #include <utils/environment.h>
+#include <utils/fileutils.h>
 
 #include <QFuture>
 #include <QFutureSynchronizer>
@@ -93,7 +95,7 @@ public:
     public: // attributes
         QPointer<ProjectExplorer::Project> project;
         QStringList sourceFiles;
-        QStringList importPaths;
+        PathsAndLanguages importPaths;
         QStringList activeResourceFiles;
         QStringList allResourceFiles;
 
@@ -148,8 +150,8 @@ public:
     ModelManagerInterface(QObject *parent = 0);
     virtual ~ModelManagerInterface();
 
-    static Language::Enum guessLanguageOfFile(const QString &fileName);
-    static QStringList globPatternsForLanguages(const QList<Language::Enum> languages);
+    static Dialect guessLanguageOfFile(const QString &fileName);
+    static QStringList globPatternsForLanguages(const QList<Dialect> languages);
     static ModelManagerInterface *instance();
     static void writeWarning(const QString &msg);
     static WorkingCopy workingCopy();
@@ -182,7 +184,7 @@ public:
     void updateQrcFile(const QString &path);
     ProjectInfo projectInfoForPath(QString path) const;
 
-    QStringList importPaths() const;
+    PathsAndLanguages importPaths() const;
     QmlJS::QmlLanguageBundles activeBundles() const;
     QmlJS::QmlLanguageBundles extendedBundles() const;
 
@@ -193,7 +195,7 @@ public:
     LibraryInfo builtins(const Document::Ptr &doc) const;
     ViewerContext completeVContext(const ViewerContext &vCtx,
                                    const Document::Ptr &doc = Document::Ptr(0)) const;
-    ViewerContext defaultVContext(Language::Enum language = Language::Qml,
+    ViewerContext defaultVContext(Dialect language = Dialect::Qml,
                                   const Document::Ptr &doc = Document::Ptr(0),
                                   bool autoComplete = true) const;
     void setDefaultVContext(const ViewerContext &vContext);
@@ -223,7 +225,7 @@ protected slots:
     virtual void startCppQmlTypeUpdate();
 protected:
     QMutex *mutex() const;
-    virtual QHash<QString,Language::Enum> languageForSuffix() const;
+    virtual QHash<QString,Dialect> languageForSuffix() const;
     virtual void writeMessageInternal(const QString &msg) const;
     virtual WorkingCopy workingCopyInternal() const;
     virtual void addTaskInternal(QFuture<void> result, const QString &msg, const char *taskId) const;
@@ -233,26 +235,25 @@ protected:
 
     static void parseLoop(QSet<QString> &scannedPaths, QSet<QString> &newLibraries,
                           WorkingCopy workingCopyInternal, QStringList files, ModelManagerInterface *modelManager,
-                          QmlJS::Language::Enum mainLanguage, bool emitDocChangedOnDisk,
+                          QmlJS::Dialect mainLanguage, bool emitDocChangedOnDisk,
                           std::function<bool (qreal)> reportProgress);
     static void parse(QFutureInterface<void> &future,
                       WorkingCopy workingCopyInternal,
                       QStringList files,
                       ModelManagerInterface *modelManager,
-                      QmlJS::Language::Enum mainLanguage,
+                      QmlJS::Dialect mainLanguage,
                       bool emitDocChangedOnDisk);
     static void importScan(QFutureInterface<void> &future,
                     WorkingCopy workingCopyInternal,
-                    QStringList paths,
+                    PathsAndLanguages paths,
                     ModelManagerInterface *modelManager,
-                    QmlJS::Language::Enum mainLanguage,
                     bool emitDocChangedOnDisk);
     static void updateCppQmlTypes(QFutureInterface<void> &interface,
                                   ModelManagerInterface *qmlModelManager,
                                   CPlusPlus::Snapshot snapshot,
                                   QHash<QString, QPair<CPlusPlus::Document::Ptr, bool> > documents);
 
-    void maybeScan(const QStringList &importPaths, Language::Enum defaultLanguage);
+    void maybeScan(const PathsAndLanguages &importPaths);
     void updateImportPaths();
     void loadQmlTypeDescriptionsInternal(const QString &path);
     void setDefaultProject(const ProjectInfo &pInfo, ProjectExplorer::Project *p);
@@ -261,11 +262,11 @@ private:
     mutable QMutex m_mutex;
     QmlJS::Snapshot m_validSnapshot;
     QmlJS::Snapshot m_newestSnapshot;
-    QStringList m_allImportPaths;
+    PathsAndLanguages m_allImportPaths;
     QStringList m_defaultImportPaths;
     QmlJS::QmlLanguageBundles m_activeBundles;
     QmlJS::QmlLanguageBundles m_extendedBundles;
-    QHash<Language::Enum, QmlJS::ViewerContext> m_defaultVContexts;
+    QHash<Dialect, QmlJS::ViewerContext> m_defaultVContexts;
     bool m_shouldScanImports;
     QSet<QString> m_scannedPaths;
 
diff --git a/src/libs/qmljs/qmljsscopechain.cpp b/src/libs/qmljs/qmljsscopechain.cpp
index 4113e47cd3..60df0e0b19 100644
--- a/src/libs/qmljs/qmljsscopechain.cpp
+++ b/src/libs/qmljs/qmljsscopechain.cpp
@@ -258,7 +258,7 @@ void ScopeChain::update() const
         m_all += m_cppContextProperties;
 
     // the root scope in js files doesn't see instantiating components
-    if (m_document->language() != Language::JavaScript || m_jsScopes.count() != 1) {
+    if (m_document->language() != Dialect::JavaScript || m_jsScopes.count() != 1) {
         if (m_qmlComponentScope) {
             foreach (const QmlComponentChain *parent, m_qmlComponentScope->instantiatingComponents())
                 collectScopes(parent, &m_all);
diff --git a/src/libs/qmljs/qmljsviewercontext.cpp b/src/libs/qmljs/qmljsviewercontext.cpp
index cec6605145..14482f1158 100644
--- a/src/libs/qmljs/qmljsviewercontext.cpp
+++ b/src/libs/qmljs/qmljsviewercontext.cpp
@@ -40,11 +40,11 @@ namespace QmlJS {
     Screen information will also most likely need to be added here.
 */
 ViewerContext::ViewerContext()
-    : language(Language::Qml), flags(AddAllPaths)
+    : language(Dialect::Qml), flags(AddAllPaths)
 { }
 
 ViewerContext::ViewerContext(QStringList selectors, QStringList paths,
-                                    QmlJS::Language::Enum language,
+                                    QmlJS::Dialect language,
                                     QmlJS::ViewerContext::Flags flags)
     : selectors(selectors), paths(paths), language(language),
       flags(flags)
@@ -54,27 +54,27 @@ ViewerContext::ViewerContext(QStringList selectors, QStringList paths,
 /*
  which languages might be imported in this context
  */
-bool ViewerContext::languageIsCompatible(Language::Enum l) const
+bool ViewerContext::languageIsCompatible(Dialect l) const
 {
-    if (l == Language::AnyLanguage && language != Language::NoLanguage)
+    if (l == Dialect::AnyLanguage && language != Dialect::NoLanguage)
         return true;
-    switch (language) {
-    case Language::JavaScript:
-    case Language::Json:
-    case Language::QmlProject:
-    case Language::QmlQbs:
-    case Language::QmlTypeInfo:
+    switch (language.dialect()) {
+    case Dialect::JavaScript:
+    case Dialect::Json:
+    case Dialect::QmlProject:
+    case Dialect::QmlQbs:
+    case Dialect::QmlTypeInfo:
         return language == l;
-    case Language::Qml:
-        return l == Language::Qml || l == Language::QmlQtQuick1 || l == Language::QmlQtQuick2
-                || l == Language::JavaScript;
-    case Language::QmlQtQuick1:
-        return l == Language::Qml || l == Language::QmlQtQuick1 || l == Language::JavaScript;
-    case Language::QmlQtQuick2:
-        return l == Language::Qml || l == Language::QmlQtQuick2 || l == Language::JavaScript;
-    case Language::AnyLanguage:
+    case Dialect::Qml:
+        return l == Dialect::Qml || l == Dialect::QmlQtQuick1 || l == Dialect::QmlQtQuick2
+                || l == Dialect::JavaScript;
+    case Dialect::QmlQtQuick1:
+        return l == Dialect::Qml || l == Dialect::QmlQtQuick1 || l == Dialect::JavaScript;
+    case Dialect::QmlQtQuick2:
+        return l == Dialect::Qml || l == Dialect::QmlQtQuick2 || l == Dialect::JavaScript;
+    case Dialect::AnyLanguage:
         return true;
-    case Language::NoLanguage:
+    case Dialect::NoLanguage:
         break;
     }
     return false;
diff --git a/src/libs/qmljs/qmljsviewercontext.h b/src/libs/qmljs/qmljsviewercontext.h
index f4b3639226..1e5c7c262a 100644
--- a/src/libs/qmljs/qmljsviewercontext.h
+++ b/src/libs/qmljs/qmljsviewercontext.h
@@ -32,6 +32,7 @@
 
 #include "qmljs_global.h"
 #include "qmljsconstants.h"
+#include "qmljsdialect.h"
 
 #include <QStringList>
 
@@ -50,15 +51,15 @@ public:
 
     ViewerContext();
     ViewerContext(QStringList selectors, QStringList paths,
-                  Language::Enum language = Language::Qml,
+                  Dialect language = Dialect::Qml,
                   Flags flags = AddAllPaths);
 
-    bool languageIsCompatible(Language::Enum l) const;
+    bool languageIsCompatible(Dialect l) const;
     void maybeAddPath(const QString &path);
 
     QStringList selectors;
     QStringList paths;
-    Language::Enum language;
+    Dialect language;
     Flags flags;
 };
 
diff --git a/src/plugins/qmakeprojectmanager/qmakeproject.cpp b/src/plugins/qmakeprojectmanager/qmakeproject.cpp
index ccfcc4d7a2..83ac0be0f4 100644
--- a/src/plugins/qmakeprojectmanager/qmakeproject.cpp
+++ b/src/plugins/qmakeprojectmanager/qmakeproject.cpp
@@ -610,7 +610,9 @@ void QmakeProject::updateQmlJSCodeModel()
 
     bool hasQmlLib = false;
     foreach (QmakeProFileNode *node, proFiles) {
-        projectInfo.importPaths.append(node->variableValue(QmlImportPathVar));
+        foreach (const QString &path, node->variableValue(QmlImportPathVar))
+            projectInfo.importPaths.maybeInsert(Utils::FileName::fromString(path),
+                                                QmlJS::Dialect::Qml);
         projectInfo.activeResourceFiles.append(node->variableValue(ExactResourceVar));
         projectInfo.allResourceFiles.append(node->variableValue(ResourceVar));
         if (!hasQmlLib) {
@@ -630,7 +632,6 @@ void QmakeProject::updateQmlJSCodeModel()
         pl.add(ProjectExplorer::Constants::LANG_QMLJS);
     setProjectLanguages(pl);
 
-    projectInfo.importPaths.removeDuplicates();
     projectInfo.activeResourceFiles.removeDuplicates();
     projectInfo.allResourceFiles.removeDuplicates();
 
diff --git a/src/plugins/qmldesigner/designercore/filemanager/astobjecttextextractor.cpp b/src/plugins/qmldesigner/designercore/filemanager/astobjecttextextractor.cpp
index c247d90f13..c3eb6e8c7d 100644
--- a/src/plugins/qmldesigner/designercore/filemanager/astobjecttextextractor.cpp
+++ b/src/plugins/qmldesigner/designercore/filemanager/astobjecttextextractor.cpp
@@ -36,7 +36,7 @@ using namespace QmlDesigner;
 using namespace QmlJS::AST;
 
 ASTObjectTextExtractor::ASTObjectTextExtractor(const QString &text):
-        m_document(Document::create("<ASTObjectTextExtractor>", Language::Qml))
+        m_document(Document::create("<ASTObjectTextExtractor>", Dialect::Qml))
 {
     m_document->setSource(text);
     m_document->parseQml();
diff --git a/src/plugins/qmldesigner/designercore/filemanager/firstdefinitionfinder.cpp b/src/plugins/qmldesigner/designercore/filemanager/firstdefinitionfinder.cpp
index 340b27a4b2..b044dfabb2 100644
--- a/src/plugins/qmldesigner/designercore/filemanager/firstdefinitionfinder.cpp
+++ b/src/plugins/qmldesigner/designercore/filemanager/firstdefinitionfinder.cpp
@@ -38,7 +38,7 @@ using namespace QmlDesigner;
 using namespace QmlJS::AST;
 
 FirstDefinitionFinder::FirstDefinitionFinder(const QString &text):
-        m_doc(Document::create("<internal>", Language::Qml))
+        m_doc(Document::create("<internal>", Dialect::Qml))
 {
     m_doc->setSource(text);
     bool ok = m_doc->parseQml();
diff --git a/src/plugins/qmldesigner/designercore/filemanager/objectlengthcalculator.cpp b/src/plugins/qmldesigner/designercore/filemanager/objectlengthcalculator.cpp
index 6ce6a7aaff..c9d920d387 100644
--- a/src/plugins/qmldesigner/designercore/filemanager/objectlengthcalculator.cpp
+++ b/src/plugins/qmldesigner/designercore/filemanager/objectlengthcalculator.cpp
@@ -36,7 +36,7 @@ using namespace QmlDesigner;
 using namespace QmlJS::AST;
 
 ObjectLengthCalculator::ObjectLengthCalculator():
-        m_doc(Document::create("<internal>", Language::Qml))
+        m_doc(Document::create("<internal>", Dialect::Qml))
 {
 }
 
diff --git a/src/plugins/qmldesigner/designercore/filemanager/qmlrefactoring.cpp b/src/plugins/qmldesigner/designercore/filemanager/qmlrefactoring.cpp
index 7dc79a2074..51b80a588f 100644
--- a/src/plugins/qmldesigner/designercore/filemanager/qmlrefactoring.cpp
+++ b/src/plugins/qmldesigner/designercore/filemanager/qmlrefactoring.cpp
@@ -59,7 +59,7 @@ bool QmlRefactoring::reparseDocument()
 
 //    qDebug() << "QmlRefactoring::reparseDocument() new QML source:" << newSource;
 
-    Document::MutablePtr tmpDocument(Document::create("<ModelToTextMerger>", Language::Qml));
+    Document::MutablePtr tmpDocument(Document::create("<ModelToTextMerger>", Dialect::Qml));
     tmpDocument->setSource(newSource);
 
     if (tmpDocument->parseQml()) {
diff --git a/src/plugins/qmldesigner/designercore/metainfo/subcomponentmanager.cpp b/src/plugins/qmldesigner/designercore/metainfo/subcomponentmanager.cpp
index fc92f460d1..74b8234653 100644
--- a/src/plugins/qmldesigner/designercore/metainfo/subcomponentmanager.cpp
+++ b/src/plugins/qmldesigner/designercore/metainfo/subcomponentmanager.cpp
@@ -82,7 +82,7 @@ static inline bool checkIfDerivedFromItem(const QString &fileName)
 
     QmlJS::Document::MutablePtr document =
             QmlJS::Document::create(fileName.isEmpty() ?
-                                        QStringLiteral("<internal>") : fileName, QmlJS::Language::Qml);
+                                        QStringLiteral("<internal>") : fileName, QmlJS::Dialect::Qml);
     document->setSource(source);
     document->parseQml();
 
diff --git a/src/plugins/qmldesigner/designercore/model/modeltotextmerger.cpp b/src/plugins/qmldesigner/designercore/model/modeltotextmerger.cpp
index b493514c77..1623e1ab21 100644
--- a/src/plugins/qmldesigner/designercore/model/modeltotextmerger.cpp
+++ b/src/plugins/qmldesigner/designercore/model/modeltotextmerger.cpp
@@ -222,7 +222,7 @@ void ModelToTextMerger::applyChanges()
     if (m_rewriteActions.isEmpty())
         return;
 
-    Document::MutablePtr tmpDocument(Document::create(QStringLiteral("<ModelToTextMerger>"), Language::Qml));
+    Document::MutablePtr tmpDocument(Document::create(QStringLiteral("<ModelToTextMerger>"), Dialect::Qml));
     tmpDocument->setSource(m_rewriterView->textModifier()->text());
     if (!tmpDocument->parseQml()) {
         qDebug() << "*** Possible problem: QML file wasn't parsed correctly.";
diff --git a/src/plugins/qmldesigner/designercore/model/plaintexteditmodifier.cpp b/src/plugins/qmldesigner/designercore/model/plaintexteditmodifier.cpp
index 71c22c9d3d..25eadec4e1 100644
--- a/src/plugins/qmldesigner/designercore/model/plaintexteditmodifier.cpp
+++ b/src/plugins/qmldesigner/designercore/model/plaintexteditmodifier.cpp
@@ -204,7 +204,7 @@ QStringList PlainTextEditModifier::importPaths() const
         QString documentFilePath = textDocument()->baseUrl().toLocalFile();
         if (!documentFilePath.isEmpty()) {
             QmlJS::Document::Ptr qmljsDocument = modelManager->snapshot().document(documentFilePath);
-            return modelManager->defaultVContext(QmlJS::Language::Qml, qmljsDocument, true).paths;
+            return modelManager->defaultVContext(QmlJS::Dialect::Qml, qmljsDocument, true).paths;
         }
     }
 
diff --git a/src/plugins/qmldesigner/designercore/model/texttomodelmerger.cpp b/src/plugins/qmldesigner/designercore/model/texttomodelmerger.cpp
index 8a1ba2e664..7807e91aad 100644
--- a/src/plugins/qmldesigner/designercore/model/texttomodelmerger.cpp
+++ b/src/plugins/qmldesigner/designercore/model/texttomodelmerger.cpp
@@ -828,7 +828,7 @@ bool TextToModelMerger::load(const QString &data, DifferenceHandler &differenceH
     try {
         Snapshot snapshot = m_rewriterView->textModifier()->qmljsSnapshot();
         const QString fileName = url.toLocalFile();
-        Document::MutablePtr doc = Document::create(fileName.isEmpty() ? QStringLiteral("<internal>") : fileName, Language::Qml);
+        Document::MutablePtr doc = Document::create(fileName.isEmpty() ? QStringLiteral("<internal>") : fileName, Dialect::Qml);
         doc->setSource(data);
         doc->parseQml();
 
@@ -841,7 +841,7 @@ bool TextToModelMerger::load(const QString &data, DifferenceHandler &differenceH
             return false;
         }
         snapshot.insert(doc);
-        QmlJS::ViewerContext vContext = QmlJS::ModelManagerInterface::instance()->defaultVContext(Language::Qml, doc, true);
+        QmlJS::ViewerContext vContext = QmlJS::ModelManagerInterface::instance()->defaultVContext(Dialect::Qml, doc, true);
         ReadingContext ctxt(snapshot, doc, vContext);
         m_scopeChain = QSharedPointer<const ScopeChain>(
                     new ScopeChain(ctxt.scopeChain()));
diff --git a/src/plugins/qmldesigner/qmldesignerplugin.cpp b/src/plugins/qmldesigner/qmldesignerplugin.cpp
index 8a08aaf055..2c846eb851 100644
--- a/src/plugins/qmldesigner/qmldesignerplugin.cpp
+++ b/src/plugins/qmldesigner/qmldesignerplugin.cpp
@@ -364,9 +364,9 @@ static bool checkIfEditorIsQtQuick(Core::IEditor *editor)
         QmlJS::ModelManagerInterface *modelManager = QmlJS::ModelManagerInterface::instance();
         QmlJS::Document::Ptr document = modelManager->ensuredGetDocumentForPath(editor->document()->filePath());
         if (!document.isNull())
-            return document->language() == QmlJS::Language::QmlQtQuick1
-                    || document->language() == QmlJS::Language::QmlQtQuick2
-                    || document->language() == QmlJS::Language::Qml;
+            return document->language() == QmlJS::Dialect::QmlQtQuick1
+                    || document->language() == QmlJS::Dialect::QmlQtQuick2
+                    || document->language() == QmlJS::Dialect::Qml;
     }
 
     return false;
diff --git a/src/plugins/qmljseditor/qmlexpressionundercursor.cpp b/src/plugins/qmljseditor/qmlexpressionundercursor.cpp
index 39f2b09f14..aa6510f43a 100644
--- a/src/plugins/qmljseditor/qmlexpressionundercursor.cpp
+++ b/src/plugins/qmljseditor/qmlexpressionundercursor.cpp
@@ -134,7 +134,7 @@ QmlJS::AST::ExpressionNode *QmlExpressionUnderCursor::operator()(const QTextCurs
     _text = expressionUnderCursor(cursor);
 
     Document::MutablePtr newDoc = Document::create(
-                QLatin1String("<expression>"), Language::JavaScript);
+                QLatin1String("<expression>"), Dialect::JavaScript);
     newDoc->setSource(_text);
     newDoc->parseExpression();
     exprDoc = newDoc;
diff --git a/src/plugins/qmljseditor/qmljseditor.cpp b/src/plugins/qmljseditor/qmljseditor.cpp
index 1b2c3ff137..51e656203d 100644
--- a/src/plugins/qmljseditor/qmljseditor.cpp
+++ b/src/plugins/qmljseditor/qmljseditor.cpp
@@ -232,7 +232,7 @@ void QmlJSTextEditorWidget::updateCodeWarnings(QmlJS::Document::Ptr doc)
 {
     if (doc->ast()) {
         setExtraSelections(CodeWarningsSelection, QList<QTextEdit::ExtraSelection>());
-    } else if (Document::isFullySupportedLanguage(doc->language())) {
+    } else if (doc->language().isFullySupportedLanguage()) {
         // show parsing errors
         QList<QTextEdit::ExtraSelection> selections;
         appendExtraSelectionsForMessages(&selections, doc->diagnosticMessages(), document());
diff --git a/src/plugins/qmljseditor/qmljsfindreferences.cpp b/src/plugins/qmljseditor/qmljsfindreferences.cpp
index 0af1dbd349..01698457ce 100644
--- a/src/plugins/qmljseditor/qmljsfindreferences.cpp
+++ b/src/plugins/qmljseditor/qmljsfindreferences.cpp
@@ -812,14 +812,14 @@ static void find_helper(QFutureInterface<FindReferences::Usage> &future,
         if (oldDoc && oldDoc->editorRevision() == it.value().second)
             continue;
 
-        Language::Enum language;
+        Dialect language;
         if (oldDoc)
             language = oldDoc->language();
         else
             language = ModelManagerInterface::guessLanguageOfFile(fileName);
-        if (language == Language::NoLanguage) {
+        if (language == Dialect::NoLanguage) {
             qCDebug(qmljsLog) << "NoLanguage in qmljsfindreferences.cpp find_helper for " << fileName;
-            language = Language::AnyLanguage;
+            language = Dialect::AnyLanguage;
         }
 
         Document::MutablePtr newDoc = snapshot.documentFromSource(
diff --git a/src/plugins/qmljseditor/qmljssemantichighlighter.cpp b/src/plugins/qmljseditor/qmljssemantichighlighter.cpp
index 4d76c94eae..f597d29078 100644
--- a/src/plugins/qmljseditor/qmljssemantichighlighter.cpp
+++ b/src/plugins/qmljseditor/qmljssemantichighlighter.cpp
@@ -434,7 +434,7 @@ private:
     void run()
     {
         int nMessages = 0;
-        if (Document::isFullySupportedLanguage(m_scopeChain.document()->language())) {
+        if (m_scopeChain.document()->language().isFullySupportedLanguage()) {
             nMessages = m_scopeChain.document()->diagnosticMessages().size()
                     + m_semanticInfo.semanticMessages.size()
                     + m_semanticInfo.staticAnalysisMessages.size();
diff --git a/src/plugins/qmljseditor/qmljssemanticinfoupdater.cpp b/src/plugins/qmljseditor/qmljssemanticinfoupdater.cpp
index 84d280aa24..3a5743945a 100644
--- a/src/plugins/qmljseditor/qmljssemanticinfoupdater.cpp
+++ b/src/plugins/qmljseditor/qmljssemanticinfoupdater.cpp
@@ -128,7 +128,7 @@ QmlJSTools::SemanticInfo SemanticInfoUpdater::makeNewSemanticInfo(const QmlJS::D
     ScopeChain *scopeChain = new ScopeChain(doc, semanticInfo.context);
     semanticInfo.setRootScopeChain(QSharedPointer<const ScopeChain>(scopeChain));
 
-    if (doc->language() == Language::Json) {
+    if (doc->language() == Dialect::Json) {
         Utils::JsonSchema *schema =
                 QmlJSEditorPlugin::instance()->jsonManager()->schemaForFile(doc->fileName());
         if (schema) {
diff --git a/src/plugins/qmljseditor/qmltaskmanager.cpp b/src/plugins/qmljseditor/qmltaskmanager.cpp
index cf3e35ead3..dbc50b59d3 100644
--- a/src/plugins/qmljseditor/qmltaskmanager.cpp
+++ b/src/plugins/qmljseditor/qmltaskmanager.cpp
@@ -109,7 +109,7 @@ void QmlTaskManager::collectMessages(
 
             FileErrorMessages result;
             result.fileName = fileName;
-            if (Document::isFullySupportedLanguage(document->language())) {
+            if (document->language().isFullySupportedLanguage()) {
                 result.tasks = convertToTasks(document->diagnosticMessages(),
                                               Utils::FileName::fromString(fileName),
                                               Core::Id(Constants::TASK_CATEGORY_QML));
@@ -161,7 +161,7 @@ void QmlTaskManager::updateMessagesNow(bool updateSemantic)
     QFuture<FileErrorMessages> future =
             QtConcurrent::run<FileErrorMessages>(
                 &collectMessages, modelManager->newestSnapshot(), modelManager->projectInfos(),
-                modelManager->defaultVContext(Language::AnyLanguage), updateSemantic);
+                modelManager->defaultVContext(Dialect::AnyLanguage), updateSemantic);
     m_messageCollector.setFuture(future);
 }
 
diff --git a/src/plugins/qmljstools/qmljsbundleprovider.cpp b/src/plugins/qmljstools/qmljsbundleprovider.cpp
index 1c065c2c81..5b125591f1 100644
--- a/src/plugins/qmljstools/qmljsbundleprovider.cpp
+++ b/src/plugins/qmljstools/qmljsbundleprovider.cpp
@@ -112,21 +112,21 @@ void BasicBundleProvider::mergeBundlesForKit(ProjectExplorer::Kit *kit
 {
     QHash<QString,QString> myReplacements = replacements;
 
-    bundles.mergeBundleForLanguage(Language::QmlQbs, defaultQbsBundle());
-    bundles.mergeBundleForLanguage(Language::QmlTypeInfo, defaultQmltypesBundle());
-    bundles.mergeBundleForLanguage(Language::QmlProject, defaultQmlprojectBundle());
+    bundles.mergeBundleForLanguage(Dialect::QmlQbs, defaultQbsBundle());
+    bundles.mergeBundleForLanguage(Dialect::QmlTypeInfo, defaultQmltypesBundle());
+    bundles.mergeBundleForLanguage(Dialect::QmlProject, defaultQmlprojectBundle());
 
     QtSupport::BaseQtVersion *qtVersion = QtSupport::QtKitInformation::qtVersion(kit);
     if (!qtVersion) {
         QmlBundle b1(defaultQt4QtQuick1Bundle());
-        bundles.mergeBundleForLanguage(Language::Qml, b1);
-        bundles.mergeBundleForLanguage(Language::QmlQtQuick1, b1);
+        bundles.mergeBundleForLanguage(Dialect::Qml, b1);
+        bundles.mergeBundleForLanguage(Dialect::QmlQtQuick1, b1);
         QmlBundle b11(defaultQt5QtQuick1Bundle());
-        bundles.mergeBundleForLanguage(Language::Qml, b11);
-        bundles.mergeBundleForLanguage(Language::QmlQtQuick1, b11);
+        bundles.mergeBundleForLanguage(Dialect::Qml, b11);
+        bundles.mergeBundleForLanguage(Dialect::QmlQtQuick1, b11);
         QmlBundle b2(defaultQt5QtQuick2Bundle());
-        bundles.mergeBundleForLanguage(Language::Qml, b2);
-        bundles.mergeBundleForLanguage(Language::QmlQtQuick2, b2);
+        bundles.mergeBundleForLanguage(Dialect::Qml, b2);
+        bundles.mergeBundleForLanguage(Dialect::QmlQtQuick2, b2);
         return;
     }
     QString qtImportsPath = qtVersion->qmakeProperty("QT_INSTALL_IMPORTS");
@@ -157,8 +157,8 @@ void BasicBundleProvider::mergeBundlesForKit(ProjectExplorer::Kit *kit
                 qtQuick1Bundle.merge(defaultQt5QtQuick1Bundle());
         }
         qtQuick1Bundle.replaceVars(myReplacements);
-        bundles.mergeBundleForLanguage(Language::Qml, qtQuick1Bundle);
-        bundles.mergeBundleForLanguage(Language::QmlQtQuick1, qtQuick1Bundle);
+        bundles.mergeBundleForLanguage(Dialect::Qml, qtQuick1Bundle);
+        bundles.mergeBundleForLanguage(Dialect::QmlQtQuick1, qtQuick1Bundle);
     }
     if (features.contains(Core::Feature(QtSupport::Constants::FEATURE_QT_QUICK_2))) {
         myReplacements.insert(QLatin1String("$(CURRENT_DIRECTORY)"), qtQmlPath);
@@ -179,8 +179,8 @@ void BasicBundleProvider::mergeBundlesForKit(ProjectExplorer::Kit *kit
             qtQuick2Bundle.merge(defaultQt5QtQuick2Bundle());
         }
         qtQuick2Bundle.replaceVars(myReplacements);
-        bundles.mergeBundleForLanguage(Language::Qml, qtQuick2Bundle);
-        bundles.mergeBundleForLanguage(Language::QmlQtQuick2, qtQuick2Bundle);
+        bundles.mergeBundleForLanguage(Dialect::Qml, qtQuick2Bundle);
+        bundles.mergeBundleForLanguage(Dialect::QmlQtQuick2, qtQuick2Bundle);
     }
 }
 
diff --git a/src/plugins/qmljstools/qmljsmodelmanager.cpp b/src/plugins/qmljstools/qmljsmodelmanager.cpp
index 7f95370e8d..fc3f0f744b 100644
--- a/src/plugins/qmljstools/qmljsmodelmanager.cpp
+++ b/src/plugins/qmljstools/qmljsmodelmanager.cpp
@@ -174,26 +174,26 @@ void QmlJSTools::setupProjectInfoQmlBundles(ModelManagerInterface::ProjectInfo &
     }
 }
 
-QHash<QString,QmlJS::Language::Enum> ModelManager::languageForSuffix() const
+QHash<QString,QmlJS::Dialect> ModelManager::languageForSuffix() const
 {
-    QHash<QString,QmlJS::Language::Enum> res = ModelManagerInterface::languageForSuffix();
+    QHash<QString,QmlJS::Dialect> res = ModelManagerInterface::languageForSuffix();
 
     if (ICore::instance()) {
         MimeType jsSourceTy = MimeDatabase::findByType(QLatin1String(Constants::JS_MIMETYPE));
         foreach (const QString &suffix, jsSourceTy.suffixes())
-            res[suffix] = Language::JavaScript;
+            res[suffix] = Dialect::JavaScript;
         MimeType qmlSourceTy = MimeDatabase::findByType(QLatin1String(Constants::QML_MIMETYPE));
         foreach (const QString &suffix, qmlSourceTy.suffixes())
-            res[suffix] = Language::Qml;
+            res[suffix] = Dialect::Qml;
         MimeType qbsSourceTy = MimeDatabase::findByType(QLatin1String(Constants::QBS_MIMETYPE));
         foreach (const QString &suffix, qbsSourceTy.suffixes())
-            res[suffix] = Language::QmlQbs;
+            res[suffix] = Dialect::QmlQbs;
         MimeType qmlProjectSourceTy = MimeDatabase::findByType(QLatin1String(Constants::QMLPROJECT_MIMETYPE));
         foreach (const QString &suffix, qmlProjectSourceTy.suffixes())
-            res[suffix] = Language::QmlProject;
+            res[suffix] = Dialect::QmlProject;
         MimeType jsonSourceTy = MimeDatabase::findByType(QLatin1String(Constants::JSON_MIMETYPE));
         foreach (const QString &suffix, jsonSourceTy.suffixes())
-            res[suffix] = Language::Json;
+            res[suffix] = Dialect::Json;
     }
     return res;
 }
@@ -226,7 +226,7 @@ void ModelManager::delayedInitialization()
             SLOT(updateDefaultProjectInfo()));
 
     QmlJS::ViewerContext qbsVContext;
-    qbsVContext.language = Language::QmlQbs;
+    qbsVContext.language = Dialect::QmlQbs;
     qbsVContext.maybeAddPath(ICore::resourcePath() + QLatin1String("/qbs"));
     setDefaultVContext(qbsVContext);
 }
diff --git a/src/plugins/qmljstools/qmljsmodelmanager.h b/src/plugins/qmljstools/qmljsmodelmanager.h
index ec49e637f2..ca0b2504a1 100644
--- a/src/plugins/qmljstools/qmljsmodelmanager.h
+++ b/src/plugins/qmljstools/qmljsmodelmanager.h
@@ -68,7 +68,7 @@ public:
 
     void delayedInitialization();
 protected:
-    QHash<QString, QmlJS::Language::Enum> languageForSuffix() const QTC_OVERRIDE;
+    QHash<QString, QmlJS::Dialect> languageForSuffix() const QTC_OVERRIDE;
     void writeMessageInternal(const QString &msg) const QTC_OVERRIDE;
     WorkingCopy workingCopyInternal() const QTC_OVERRIDE;
     void addTaskInternal(QFuture<void> result, const QString &msg, const char *taskId) const QTC_OVERRIDE;
diff --git a/src/plugins/qmljstools/qmljsrefactoringchanges.cpp b/src/plugins/qmljstools/qmljsrefactoringchanges.cpp
index 4ef9bb2206..fb1c14f036 100644
--- a/src/plugins/qmljstools/qmljsrefactoringchanges.cpp
+++ b/src/plugins/qmljstools/qmljsrefactoringchanges.cpp
@@ -124,7 +124,7 @@ QmlJSRefactoringFile::QmlJSRefactoringFile(const QString &fileName, const QShare
     : RefactoringFile(fileName, data)
 {
     // the RefactoringFile is invalid if its not for a file with qml or js code
-    if (ModelManagerInterface::guessLanguageOfFile(fileName) == Language::NoLanguage)
+    if (ModelManagerInterface::guessLanguageOfFile(fileName) == Dialect::NoLanguage)
         m_fileName.clear();
 }
 
diff --git a/src/plugins/qmlprofiler/qmlprofilerdetailsrewriter.cpp b/src/plugins/qmlprofiler/qmlprofilerdetailsrewriter.cpp
index 38b0808774..be79adeaca 100644
--- a/src/plugins/qmlprofiler/qmlprofilerdetailsrewriter.cpp
+++ b/src/plugins/qmlprofiler/qmlprofilerdetailsrewriter.cpp
@@ -136,7 +136,7 @@ void QmlProfilerDetailsRewriter::requestDetailsForLocation(int requestId,
     QFileInfo fileInfo(localFile);
     if (!fileInfo.exists() || !fileInfo.isReadable())
         return;
-    if (!QmlJS::Document::isQmlLikeLanguage(QmlJS::ModelManagerInterface::guessLanguageOfFile(localFile)))
+    if (!QmlJS::ModelManagerInterface::guessLanguageOfFile(localFile).isQmlLikeLanguage())
         return;
 
     PendingEvent ev = {location, localFile, requestId};
diff --git a/src/plugins/qmlprojectmanager/qmlproject.cpp b/src/plugins/qmlprojectmanager/qmlproject.cpp
index ed46381952..5b45fb560e 100644
--- a/src/plugins/qmlprojectmanager/qmlproject.cpp
+++ b/src/plugins/qmlprojectmanager/qmlproject.cpp
@@ -201,7 +201,9 @@ void QmlProject::refresh(RefreshOptions options)
 
     QmlJS::ModelManagerInterface::ProjectInfo projectInfo =
             modelManager()->defaultProjectInfoForProject(this);
-    projectInfo.importPaths = customImportPaths();
+    foreach (const QString &searchPath, customImportPaths())
+        projectInfo.importPaths.maybeInsert(Utils::FileName::fromString(searchPath),
+                                            QmlJS::Dialect::Qml);
 
     modelManager()->updateProjectInfo(projectInfo, this);
 }