Support seperate versions of installed modules

QML supports versioned types in modules. There's a version major and a
version minor.

This makes it possible to have a module com.organisation.fancycomponents
with version 1.0, and later you could ship a new module
com.organisation.fancycomponents which contains a more recent version 1.1
or 2.0 AND also the old versions to keep old code running.

This is good.

The problem is that this is difficult with certain QA procedures. It's
hard to verify that a new module is indeed 100% compatible with the
previous versions.

The change extends the import mechanism by adding optional versioning to
the component patch.

With the patch, you can add a new module
com.organisation.fancycomponents.2.0 which will be loaded when the
QML file specifies "import com.organisation.fancycomponents 2.0".

The patch works as follows: if you try to load
com.organisation.fancycomponents in version 2.0, the engine first
looks for com/organisation/fancycomponents.2.0, then for
com/organisation/fancycomponents.2 then for
com.organisation/fancycomponents.

Reviewed-by: Aaron Kennedy
Task-number: QTBUG-16455

12 files changed, 302 insertions, 13 deletions

diff --git a/doc/src/declarative/modules.qdoc b/doc/src/declarative/modules.qdoc
index 1dca28c..4b2b33a 100644
--- a/doc/src/declarative/modules.qdoc
+++ b/doc/src/declarative/modules.qdoc
@@ -134,6 +134,15 @@ Installed modules that are installed into the import path or created
 as a \l{QDeclarativeExtensionPlugin}{QML C++ plugin} must define a
 \l{Writing a qmldir file}{qmldir file}.
 
+Modules that are installed into the import path translate the URI into
+directory names. For example, the qmldir file of the module \c com.nokia.qml.mymodule
+must be located in the subpath \c com/nokia/qml/mymodule/qmldir somewhere in the
+QML import path. In addition it is possible to store different versions of the
+module in subdirectories of its own. For example, a version 2.1 of the
+module could be located under \c com/nokia/qml/mymodule.2/qmldir or
+\c com/nokia/qml/mymodule.2.1/qmldir. The engine will automatically load
+the module which matches best.
+
 
 \section2 The QML import path
 
diff --git a/src/declarative/qml/qdeclarativeimport.cpp b/src/declarative/qml/qdeclarativeimport.cpp
index c89666d..22dcb44 100644
--- a/src/declarative/qml/qdeclarativeimport.cpp
+++ b/src/declarative/qml/qdeclarativeimport.cpp
@@ -425,8 +425,18 @@ QString QDeclarativeImportsPrivate::resolvedUri(const QString &dir_arg, QDeclara
             break;
         }
     }
+
+    stableRelativePath.replace(QLatin1Char('\\'), QLatin1Char('/'));
+
+    // remove optional versioning in dot notation from uri
+    int lastSlash = stableRelativePath.lastIndexOf(QLatin1Char('/'));
+    if (lastSlash >= 0) {
+        int versionDot = stableRelativePath.indexOf(QLatin1Char('.'), lastSlash);
+        if (versionDot >= 0)
+            stableRelativePath = stableRelativePath.left(versionDot);
+    }
+
     stableRelativePath.replace(QLatin1Char('/'), QLatin1Char('.'));
-    stableRelativePath.replace(QLatin1Char('\\'), QLatin1Char('.'));
     return stableRelativePath;
 }
 
@@ -453,20 +463,62 @@ bool QDeclarativeImportsPrivate::add(const QDeclarativeDirComponents &qmldircomp
         QString dir;
 
 
-        foreach (const QString &p, database->fileImportPath) {
-            dir = p+QLatin1Char('/')+url;
+        // step 1: search for extension with fully encoded version number
+        if (vmaj >= 0 && vmin >= 0) {
+            foreach (const QString &p, database->fileImportPath) {
+                dir = p+QLatin1Char('/')+url;
 
-            QFileInfo fi(dir+QLatin1String("/qmldir"));
-            const QString absoluteFilePath = fi.absoluteFilePath();
+                QFileInfo fi(dir+QString(QLatin1String(".%1.%2")).arg(vmaj).arg(vmin)+QLatin1String("/qmldir"));
+                const QString absoluteFilePath = fi.absoluteFilePath();
 
-            if (fi.isFile()) {
-                found = true;
+                if (fi.isFile()) {
+                    found = true;
 
-                url = QUrl::fromLocalFile(fi.absolutePath()).toString();
-                uri = resolvedUri(dir, database);
-                if (!importExtension(absoluteFilePath, uri, database, &qmldircomponents, errorString))
-                    return false;
-                break;
+                    url = QUrl::fromLocalFile(fi.absolutePath()).toString();
+                    uri = resolvedUri(dir, database);
+                    if (!importExtension(absoluteFilePath, uri, database, &qmldircomponents, errorString))
+                        return false;
+                    break;
+                }
+            }
+        }
+        // step 2: search for extension with encoded version major
+        if (vmaj >= 0 && vmin >= 0) {
+            foreach (const QString &p, database->fileImportPath) {
+                dir = p+QLatin1Char('/')+url;
+
+                QFileInfo fi(dir+QString(QLatin1String(".%1")).arg(vmaj)+QLatin1String("/qmldir"));
+                const QString absoluteFilePath = fi.absoluteFilePath();
+
+                if (fi.isFile()) {
+                    found = true;
+
+                    url = QUrl::fromLocalFile(fi.absolutePath()).toString();
+                    uri = resolvedUri(dir, database);
+                    if (!importExtension(absoluteFilePath, uri, database, &qmldircomponents, errorString))
+                        return false;
+                    break;
+                }
+            }
+        }
+        if (!found) {
+            // step 3: search for extension without version number
+
+            foreach (const QString &p, database->fileImportPath) {
+                dir = p+QLatin1Char('/')+url;
+
+                QFileInfo fi(dir+QLatin1String("/qmldir"));
+                const QString absoluteFilePath = fi.absoluteFilePath();
+
+                if (fi.isFile()) {
+                    found = true;
+
+                    url = QUrl::fromLocalFile(fi.absolutePath()).toString();
+                    uri = resolvedUri(dir, database);
+                    if (!importExtension(absoluteFilePath, uri, database, &qmldircomponents, errorString))
+                        return false;
+                    break;
+                }
             }
         }
 
diff --git a/tests/auto/declarative/qdeclarativemoduleplugin/data/works2.qml b/tests/auto/declarative/qdeclarativemoduleplugin/data/works2.qml
new file mode 100644
index 0000000..cc322bf
--- /dev/null
+++ b/tests/auto/declarative/qdeclarativemoduleplugin/data/works2.qml
@@ -0,0 +1,3 @@
+import com.nokia.AutoTestQmlPluginType 2.0
+
+MyPluginType { valueOnlyIn2: 123 }
diff --git a/tests/auto/declarative/qdeclarativemoduleplugin/data/works21.qml b/tests/auto/declarative/qdeclarativemoduleplugin/data/works21.qml
new file mode 100644
index 0000000..c08160a
--- /dev/null
+++ b/tests/auto/declarative/qdeclarativemoduleplugin/data/works21.qml
@@ -0,0 +1,3 @@
+import com.nokia.AutoTestQmlPluginType 2.1
+
+MyPluginType { valueOnlyIn2: 123 }
diff --git a/tests/auto/declarative/qdeclarativemoduleplugin/imports/com/nokia/AutoTestQmlPluginType.2.1/qmldir b/tests/auto/declarative/qdeclarativemoduleplugin/imports/com/nokia/AutoTestQmlPluginType.2.1/qmldir
new file mode 100644
index 0000000..0a8b5d4
--- /dev/null
+++ b/tests/auto/declarative/qdeclarativemoduleplugin/imports/com/nokia/AutoTestQmlPluginType.2.1/qmldir
@@ -0,0 +1 @@
+plugin plugin
diff --git a/tests/auto/declarative/qdeclarativemoduleplugin/imports/com/nokia/AutoTestQmlPluginType.2/qmldir b/tests/auto/declarative/qdeclarativemoduleplugin/imports/com/nokia/AutoTestQmlPluginType.2/qmldir
new file mode 100644
index 0000000..0a8b5d4
--- /dev/null
+++ b/tests/auto/declarative/qdeclarativemoduleplugin/imports/com/nokia/AutoTestQmlPluginType.2/qmldir
@@ -0,0 +1 @@
+plugin plugin
diff --git a/tests/auto/declarative/qdeclarativemoduleplugin/plugin.2.1/plugin.2.1.pro b/tests/auto/declarative/qdeclarativemoduleplugin/plugin.2.1/plugin.2.1.pro
new file mode 100644
index 0000000..661675a
--- /dev/null
+++ b/tests/auto/declarative/qdeclarativemoduleplugin/plugin.2.1/plugin.2.1.pro
@@ -0,0 +1,9 @@
+TEMPLATE = lib
+CONFIG += plugin
+SOURCES = plugin.cpp
+QT = core declarative
+DESTDIR = ../imports/com/nokia/AutoTestQmlPluginType.2.1
+
+symbian: {
+    TARGET.EPOCALLOWDLLDATA=1
+}
diff --git a/tests/auto/declarative/qdeclarativemoduleplugin/plugin.2.1/plugin.cpp b/tests/auto/declarative/qdeclarativemoduleplugin/plugin.2.1/plugin.cpp
new file mode 100644
index 0000000..1ae2bd4
--- /dev/null
+++ b/tests/auto/declarative/qdeclarativemoduleplugin/plugin.2.1/plugin.cpp
@@ -0,0 +1,84 @@
+/****************************************************************************
+**
+** Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the test suite of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** No Commercial Usage
+** This file contains pre-release code and may not be distributed.
+** You may use this file in accordance with the terms and conditions
+** contained in the Technology Preview License Agreement accompanying
+** this package.
+**
+** 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, Nokia gives you certain additional
+** rights.  These rights are described in the Nokia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** If you have questions regarding the use of this file, please contact
+** Nokia at qt-info@nokia.com.
+**
+**
+**
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+#include <QStringList>
+#include <QtDeclarative/qdeclarativeextensionplugin.h>
+#include <QtDeclarative/qdeclarative.h>
+#include <QDebug>
+
+class MyPluginType : public QObject
+{
+    Q_OBJECT
+    Q_PROPERTY(int value READ value WRITE setValue)
+    Q_PROPERTY(int valueOnlyIn2 READ value WRITE setValue)
+
+public:
+    MyPluginType(QObject *parent=0) : QObject(parent)
+    {
+        qWarning("import2.1 worked");
+    }
+
+    int value() const { return v; }
+    void setValue(int i) { v = i; }
+
+private:
+    int v;
+};
+
+
+class MyPlugin : public QDeclarativeExtensionPlugin
+{
+    Q_OBJECT
+public:
+    MyPlugin()
+    {
+        qWarning("plugin2.1 created");
+    }
+
+    void registerTypes(const char *uri)
+    {
+        Q_ASSERT(QLatin1String(uri) == "com.nokia.AutoTestQmlPluginType");
+        qmlRegisterType<MyPluginType>(uri, 2, 1, "MyPluginType");
+    }
+};
+
+#include "plugin.moc"
+
+Q_EXPORT_PLUGIN2(plugin, MyPlugin);
diff --git a/tests/auto/declarative/qdeclarativemoduleplugin/plugin.2/plugin.2.pro b/tests/auto/declarative/qdeclarativemoduleplugin/plugin.2/plugin.2.pro
new file mode 100644
index 0000000..d254642
--- /dev/null
+++ b/tests/auto/declarative/qdeclarativemoduleplugin/plugin.2/plugin.2.pro
@@ -0,0 +1,9 @@
+TEMPLATE = lib
+CONFIG += plugin
+SOURCES = plugin.cpp
+QT = core declarative
+DESTDIR = ../imports/com/nokia/AutoTestQmlPluginType.2
+
+symbian: {
+    TARGET.EPOCALLOWDLLDATA=1
+}
diff --git a/tests/auto/declarative/qdeclarativemoduleplugin/plugin.2/plugin.cpp b/tests/auto/declarative/qdeclarativemoduleplugin/plugin.2/plugin.cpp
new file mode 100644
index 0000000..6bd8542
--- /dev/null
+++ b/tests/auto/declarative/qdeclarativemoduleplugin/plugin.2/plugin.cpp
@@ -0,0 +1,84 @@
+/****************************************************************************
+**
+** Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the test suite of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** No Commercial Usage
+** This file contains pre-release code and may not be distributed.
+** You may use this file in accordance with the terms and conditions
+** contained in the Technology Preview License Agreement accompanying
+** this package.
+**
+** 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, Nokia gives you certain additional
+** rights.  These rights are described in the Nokia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** If you have questions regarding the use of this file, please contact
+** Nokia at qt-info@nokia.com.
+**
+**
+**
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+#include <QStringList>
+#include <QtDeclarative/qdeclarativeextensionplugin.h>
+#include <QtDeclarative/qdeclarative.h>
+#include <QDebug>
+
+class MyPluginType : public QObject
+{
+    Q_OBJECT
+    Q_PROPERTY(int value READ value WRITE setValue)
+    Q_PROPERTY(int valueOnlyIn2 READ value WRITE setValue)
+
+public:
+    MyPluginType(QObject *parent=0) : QObject(parent)
+    {
+        qWarning("import2 worked");
+    }
+
+    int value() const { return v; }
+    void setValue(int i) { v = i; }
+
+private:
+    int v;
+};
+
+
+class MyPlugin : public QDeclarativeExtensionPlugin
+{
+    Q_OBJECT
+public:
+    MyPlugin()
+    {
+        qWarning("plugin2 created");
+    }
+
+    void registerTypes(const char *uri)
+    {
+        Q_ASSERT(QLatin1String(uri) == "com.nokia.AutoTestQmlPluginType");
+        qmlRegisterType<MyPluginType>(uri, 2, 0, "MyPluginType");
+    }
+};
+
+#include "plugin.moc"
+
+Q_EXPORT_PLUGIN2(plugin, MyPlugin);
diff --git a/tests/auto/declarative/qdeclarativemoduleplugin/qdeclarativemoduleplugin.pro b/tests/auto/declarative/qdeclarativemoduleplugin/qdeclarativemoduleplugin.pro
index 221e465..10864df 100644
--- a/tests/auto/declarative/qdeclarativemoduleplugin/qdeclarativemoduleplugin.pro
+++ b/tests/auto/declarative/qdeclarativemoduleplugin/qdeclarativemoduleplugin.pro
@@ -1,6 +1,6 @@
 QT = core
 TEMPLATE = subdirs
-SUBDIRS = plugin pluginWrongCase
+SUBDIRS = plugin plugin.2 plugin.2.1 pluginWrongCase
 tst_qdeclarativemoduleplugin_pro.depends += plugin
 SUBDIRS += tst_qdeclarativemoduleplugin.pro
 
diff --git a/tests/auto/declarative/qdeclarativemoduleplugin/tst_qdeclarativemoduleplugin.cpp b/tests/auto/declarative/qdeclarativemoduleplugin/tst_qdeclarativemoduleplugin.cpp
index 96ec21b..7e381ee 100644
--- a/tests/auto/declarative/qdeclarativemoduleplugin/tst_qdeclarativemoduleplugin.cpp
+++ b/tests/auto/declarative/qdeclarativemoduleplugin/tst_qdeclarativemoduleplugin.cpp
@@ -54,6 +54,8 @@ public:
 
 private slots:
     void importsPlugin();
+    void importsPlugin2();
+    void importsPlugin21();
     void incorrectPluginCase();
 };
 
@@ -121,6 +123,38 @@ void tst_qdeclarativemoduleplugin::importsPlugin()
     delete object;
 }
 
+void tst_qdeclarativemoduleplugin::importsPlugin2()
+{
+    QDeclarativeEngine engine;
+    engine.addImportPath(QLatin1String(SRCDIR) + QDir::separator() + QLatin1String("imports"));
+    QTest::ignoreMessage(QtWarningMsg, "plugin2 created");
+    QTest::ignoreMessage(QtWarningMsg, "import2 worked");
+    QDeclarativeComponent component(&engine, TEST_FILE("data/works2.qml"));
+    foreach (QDeclarativeError err, component.errors())
+        qWarning() << err;
+    VERIFY_ERRORS(0);
+    QObject *object = component.create();
+    QVERIFY(object != 0);
+    QCOMPARE(object->property("value").toInt(),123);
+    delete object;
+}
+
+void tst_qdeclarativemoduleplugin::importsPlugin21()
+{
+    QDeclarativeEngine engine;
+    engine.addImportPath(QLatin1String(SRCDIR) + QDir::separator() + QLatin1String("imports"));
+    QTest::ignoreMessage(QtWarningMsg, "plugin2.1 created");
+    QTest::ignoreMessage(QtWarningMsg, "import2.1 worked");
+    QDeclarativeComponent component(&engine, TEST_FILE("data/works21.qml"));
+    foreach (QDeclarativeError err, component.errors())
+        qWarning() << err;
+    VERIFY_ERRORS(0);
+    QObject *object = component.create();
+    QVERIFY(object != 0);
+    QCOMPARE(object->property("value").toInt(),123);
+    delete object;
+}
+
 void tst_qdeclarativemoduleplugin::incorrectPluginCase()
 {
     QDeclarativeEngine engine;