CodePaster: Register type safe service object

Use Q_DECLARE_INTERFACE et al.
This provides a way to have the dependency on code pasting
optional in the using plugins (VCS, diff editor), while
still being able to use a nice API to perform the pasting itself.

Change-Id: Ia61e0066d552e45031f4aa7fd1f6693b68f92384
Reviewed-by: Christian Kandeler <christian.kandeler@theqtcompany.com>
Reviewed-by: Tobias Hunger <tobias.hunger@theqtcompany.com>
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@theqtcompany.com>

11 files changed, 135 insertions, 64 deletions

diff --git a/src/plugins/cpaster/codepasterservice.h b/src/plugins/cpaster/codepasterservice.h
new file mode 100644
index 0000000000..b8a0c43848
--- /dev/null
+++ b/src/plugins/cpaster/codepasterservice.h
@@ -0,0 +1,57 @@
+/****************************************************************************
+**
+** Copyright (C) 2015 The Qt Company Ltd.
+** Contact: http://www.qt.io/licensing
+**
+** 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 The Qt Company.  For licensing terms and
+** conditions see http://www.qt.io/terms-conditions.  For further information
+** use the contact form at http://www.qt.io/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 or version 3 as published by the Free
+** Software Foundation and appearing in the file LICENSE.LGPLv21 and
+** LICENSE.LGPLv3 included in the packaging of this file.  Please review the
+** following information to ensure the GNU Lesser General Public License
+** requirements will be met: https://www.gnu.org/licenses/lgpl.html and
+** http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, The Qt Company gives you certain additional
+** rights.  These rights are described in The Qt Company LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+****************************************************************************/
+
+
+#ifndef CODEPASTERSERVICE_H
+#define CODEPASTERSERVICE_H
+
+#include <QObject>
+#include <QString>
+
+namespace CodePaster {
+
+class Service
+{
+public:
+    virtual ~Service() {}
+
+    virtual void postText(const QString &text, const QString &mimeType) = 0;
+    virtual void postCurrentEditor() = 0;
+    virtual void postClipboard() = 0;
+};
+
+} // CodePaster
+
+QT_BEGIN_NAMESPACE
+Q_DECLARE_INTERFACE(CodePaster::Service, "CodePaster::Service")
+QT_END_NAMESPACE
+
+#endif // CODEPASTERSERVICE_H
+
diff --git a/src/plugins/cpaster/cpaster.pro b/src/plugins/cpaster/cpaster.pro
index 5bdc8e2545..cc30094162 100644
--- a/src/plugins/cpaster/cpaster.pro
+++ b/src/plugins/cpaster/cpaster.pro
@@ -13,7 +13,8 @@ HEADERS += cpasterplugin.h \
     fileshareprotocol.h \
     fileshareprotocolsettingspage.h \
     kdepasteprotocol.h \
-    urlopenprotocol.h
+    urlopenprotocol.h \
+    codepasterservice.h
 
 SOURCES += cpasterplugin.cpp \
     settingspage.cpp \
diff --git a/src/plugins/cpaster/cpasterplugin.cpp b/src/plugins/cpaster/cpasterplugin.cpp
index 462d949ea4..e51b533777 100644
--- a/src/plugins/cpaster/cpasterplugin.cpp
+++ b/src/plugins/cpaster/cpasterplugin.cpp
@@ -70,32 +70,29 @@ using namespace TextEditor;
 namespace CodePaster {
 
 /*!
-   \class CodePaster::CodePasterService
-   \brief The CodePasterService class is a service registered with PluginManager
+   \class CodePaster::Service
+   \brief The CodePaster::Service class is a service registered with PluginManager
    that provides CodePaster \c post() functionality.
-
-   \sa ExtensionSystem::PluginManager::getObjectByClassName, ExtensionSystem::invoke
-   \sa VcsBase::VcsBaseEditorWidget
 */
 
-CodePasterService::CodePasterService(QObject *parent) :
+CodePasterServiceImpl::CodePasterServiceImpl(QObject *parent) :
     QObject(parent)
 {
 }
 
-void CodePasterService::postText(const QString &text, const QString &mimeType)
+void CodePasterServiceImpl::postText(const QString &text, const QString &mimeType)
 {
     QTC_ASSERT(CodepasterPlugin::instance(), return);
     CodepasterPlugin::instance()->post(text, mimeType);
 }
 
-void CodePasterService::postCurrentEditor()
+void CodePasterServiceImpl::postCurrentEditor()
 {
     QTC_ASSERT(CodepasterPlugin::instance(), return);
     CodepasterPlugin::instance()->post(CodepasterPlugin::PasteEditor);
 }
 
-void CodePasterService::postClipboard()
+void CodePasterServiceImpl::postClipboard()
 {
     QTC_ASSERT(CodepasterPlugin::instance(), return);
     CodepasterPlugin::instance()->post(CodepasterPlugin::PasteClipboard);
@@ -176,7 +173,7 @@ bool CodepasterPlugin::initialize(const QStringList &arguments, QString *errorMe
     connect(m_fetchUrlAction, &QAction::triggered, this, &CodepasterPlugin::fetchUrl);
     cpContainer->addAction(command);
 
-    addAutoReleasedObject(new CodePasterService);
+    addAutoReleasedObject(new CodePasterServiceImpl);
 
     return true;
 }
diff --git a/src/plugins/cpaster/cpasterplugin.h b/src/plugins/cpaster/cpasterplugin.h
index 632503543a..c764b28df3 100644
--- a/src/plugins/cpaster/cpasterplugin.h
+++ b/src/plugins/cpaster/cpasterplugin.h
@@ -31,6 +31,8 @@
 #ifndef CPASTERPLUGIN_H
 #define CPASTERPLUGIN_H
 
+#include "codepasterservice.h"
+
 #include <extensionsystem/iplugin.h>
 
 #include <QStringList>
@@ -46,16 +48,17 @@ class CustomPoster;
 struct Settings;
 class Protocol;
 
-class CodePasterService : public QObject
+class CodePasterServiceImpl : public QObject, public CodePaster::Service
 {
     Q_OBJECT
+    Q_INTERFACES(CodePaster::Service)
 public:
-    explicit CodePasterService(QObject *parent = 0);
+    explicit CodePasterServiceImpl(QObject *parent = 0);
 
 public slots:
-    void postText(const QString &text, const QString &mimeType);
-    void postCurrentEditor();
-    void postClipboard();
+    void postText(const QString &text, const QString &mimeType) override;
+    void postCurrentEditor() override;
+    void postClipboard() override;
 };
 
 class CodepasterPlugin : public ExtensionSystem::IPlugin
diff --git a/src/plugins/diffeditor/diffeditor.qbs b/src/plugins/diffeditor/diffeditor.qbs
index 8a23861f95..d7266c7dfc 100644
--- a/src/plugins/diffeditor/diffeditor.qbs
+++ b/src/plugins/diffeditor/diffeditor.qbs
@@ -9,6 +9,10 @@ QtcPlugin {
     Depends { name: "Core" }
     Depends { name: "TextEditor" }
 
+    pluginRecommends: [
+        "CodePaster"
+    ]
+
     files: [
         "diffeditor.cpp",
         "diffeditor.h",
diff --git a/src/plugins/diffeditor/diffeditor_dependencies.pri b/src/plugins/diffeditor/diffeditor_dependencies.pri
index 0458f03fbe..abe8944152 100644
--- a/src/plugins/diffeditor/diffeditor_dependencies.pri
+++ b/src/plugins/diffeditor/diffeditor_dependencies.pri
@@ -5,3 +5,5 @@ QTC_LIB_DEPENDS += \
 QTC_PLUGIN_DEPENDS += \
     texteditor \
     coreplugin
+QTC_PLUGIN_RECOMMENDS += \
+    cpaster
diff --git a/src/plugins/diffeditor/sidebysidediffeditorwidget.cpp b/src/plugins/diffeditor/sidebysidediffeditorwidget.cpp
index ce218a52fb..9a5fc0abc8 100644
--- a/src/plugins/diffeditor/sidebysidediffeditorwidget.cpp
+++ b/src/plugins/diffeditor/sidebysidediffeditorwidget.cpp
@@ -56,8 +56,11 @@
 #include <coreplugin/minisplitter.h>
 #include <coreplugin/patchtool.h>
 
+#include <cpaster/codepasterservice.h>
+
 #include <extensionsystem/pluginmanager.h>
 
+#include <utils/qtcassert.h>
 #include <utils/tooltip/tooltip.h>
 
 using namespace Core;
@@ -894,11 +897,14 @@ void SideBySideDiffEditorWidget::slotLeftContextMenuRequested(QMenu *menu,
                                                               int chunkIndex)
 {
     menu->addSeparator();
-    QAction *sendChunkToCodePasterAction =
-            menu->addAction(tr("Send Chunk to CodePaster..."));
-    connect(sendChunkToCodePasterAction, &QAction::triggered,
-            this, &SideBySideDiffEditorWidget::slotSendChunkToCodePaster);
-    menu->addSeparator();
+    if (ExtensionSystem::PluginManager::getObject<CodePaster::Service>()) {
+        // optional code pasting service
+        QAction *sendChunkToCodePasterAction =
+                menu->addAction(tr("Send Chunk to CodePaster..."));
+        connect(sendChunkToCodePasterAction, &QAction::triggered,
+                this, &SideBySideDiffEditorWidget::slotSendChunkToCodePaster);
+        menu->addSeparator();
+    }
     QAction *applyAction = menu->addAction(tr("Apply Chunk..."));
     connect(applyAction, &QAction::triggered, this, &SideBySideDiffEditorWidget::slotApplyChunk);
     applyAction->setEnabled(false);
@@ -929,11 +935,14 @@ void SideBySideDiffEditorWidget::slotRightContextMenuRequested(QMenu *menu,
                                                                int chunkIndex)
 {
     menu->addSeparator();
-    QAction *sendChunkToCodePasterAction =
-            menu->addAction(tr("Send Chunk to CodePaster..."));
-    connect(sendChunkToCodePasterAction, &QAction::triggered,
-            this, &SideBySideDiffEditorWidget::slotSendChunkToCodePaster);
-    menu->addSeparator();
+    if (ExtensionSystem::PluginManager::getObject<CodePaster::Service>()) {
+        // optional code pasting service
+        QAction *sendChunkToCodePasterAction =
+                menu->addAction(tr("Send Chunk to CodePaster..."));
+        connect(sendChunkToCodePasterAction, &QAction::triggered,
+                this, &SideBySideDiffEditorWidget::slotSendChunkToCodePaster);
+        menu->addSeparator();
+    }
     QAction *revertAction = menu->addAction(tr("Revert Chunk..."));
     connect(revertAction, &QAction::triggered, this, &SideBySideDiffEditorWidget::slotRevertChunk);
     revertAction->setEnabled(false);
@@ -961,21 +970,15 @@ void SideBySideDiffEditorWidget::slotSendChunkToCodePaster()
     if (!m_document)
         return;
 
+    // Retrieve service by soft dependency.
+    auto pasteService = ExtensionSystem::PluginManager::getObject<CodePaster::Service>();
+    QTC_ASSERT(pasteService, return);
+
     const QString patch = m_document->makePatch(m_contextMenuFileIndex, m_contextMenuChunkIndex, false);
     if (patch.isEmpty())
         return;
 
-    // Retrieve service by soft dependency.
-    QObject *pasteService
-            = ExtensionSystem::PluginManager::getObjectByClassName(QLatin1String("CodePaster::CodePasterService"));
-    if (pasteService) {
-        QMetaObject::invokeMethod(pasteService, "postText",
-                                  Q_ARG(QString, patch),
-                                  Q_ARG(QString, QLatin1String(DiffEditor::Constants::DIFF_EDITOR_MIMETYPE)));
-    } else {
-        QMessageBox::information(this, tr("Unable to Paste"),
-                                 tr("Code pasting services are not available."));
-    }
+    pasteService->postText(patch, QLatin1String(Constants::DIFF_EDITOR_MIMETYPE));
 }
 
 void SideBySideDiffEditorWidget::slotApplyChunk()
diff --git a/src/plugins/diffeditor/unifieddiffeditorwidget.cpp b/src/plugins/diffeditor/unifieddiffeditorwidget.cpp
index fbc3a22064..3810a4052c 100644
--- a/src/plugins/diffeditor/unifieddiffeditorwidget.cpp
+++ b/src/plugins/diffeditor/unifieddiffeditorwidget.cpp
@@ -54,8 +54,11 @@
 #include <coreplugin/patchtool.h>
 #include <coreplugin/editormanager/editormanager.h>
 
+#include <cpaster/codepasterservice.h>
+
 #include <extensionsystem/pluginmanager.h>
 
+#include <utils/qtcassert.h>
 #include <utils/tooltip/tooltip.h>
 
 //static const int FILE_LEVEL = 1;
@@ -189,10 +192,13 @@ void UnifiedDiffEditorWidget::addContextMenuActions(QMenu *menu,
 
     menu->addSeparator();
     menu->addSeparator();
-    QAction *sendChunkToCodePasterAction =
-            menu->addAction(tr("Send Chunk to CodePaster..."));
-    connect(sendChunkToCodePasterAction, &QAction::triggered,
-            this, &UnifiedDiffEditorWidget::slotSendChunkToCodePaster);
+    if (ExtensionSystem::PluginManager::getObject<CodePaster::Service>()) {
+        // optional code pasting service
+        QAction *sendChunkToCodePasterAction =
+                menu->addAction(tr("Send Chunk to CodePaster..."));
+        connect(sendChunkToCodePasterAction, &QAction::triggered,
+                this, &UnifiedDiffEditorWidget::slotSendChunkToCodePaster);
+    }
     QAction *applyAction = menu->addAction(tr("Apply Chunk..."));
     connect(applyAction, &QAction::triggered, this, &UnifiedDiffEditorWidget::slotApplyChunk);
     QAction *revertAction = menu->addAction(tr("Revert Chunk..."));
@@ -229,23 +235,16 @@ void UnifiedDiffEditorWidget::slotSendChunkToCodePaster()
     if (!m_document)
         return;
 
+    // Retrieve service by soft dependency.
+    auto pasteService = ExtensionSystem::PluginManager::getObject<CodePaster::Service>();
+    QTC_ASSERT(pasteService, return);
+
     const QString patch = m_document->makePatch(m_contextMenuFileIndex, m_contextMenuChunkIndex, false);
 
     if (patch.isEmpty())
         return;
 
-    // Retrieve service by soft dependency.
-    QObject *pasteService =
-            ExtensionSystem::PluginManager::getObjectByClassName(
-                QLatin1String("CodePaster::CodePasterService"));
-    if (pasteService) {
-        QMetaObject::invokeMethod(pasteService, "postText",
-                                  Q_ARG(QString, patch),
-                                  Q_ARG(QString, QLatin1String(DiffEditor::Constants::DIFF_EDITOR_MIMETYPE)));
-    } else {
-        QMessageBox::information(this, tr("Unable to Paste"),
-                                 tr("Code pasting services are not available."));
-    }
+    pasteService->postText(patch, QLatin1String(Constants::DIFF_EDITOR_MIMETYPE));
 }
 
 void UnifiedDiffEditorWidget::slotApplyChunk()
diff --git a/src/plugins/vcsbase/vcsbase.qbs b/src/plugins/vcsbase/vcsbase.qbs
index d278208224..857577a46a 100644
--- a/src/plugins/vcsbase/vcsbase.qbs
+++ b/src/plugins/vcsbase/vcsbase.qbs
@@ -13,6 +13,10 @@ QtcPlugin {
     Depends { name: "ProjectExplorer" }
     Depends { name: "CppTools" }
 
+    pluginRecommends: [
+        "CodePaster"
+    ]
+
     files: [
         "baseannotationhighlighter.cpp",
         "baseannotationhighlighter.h",
diff --git a/src/plugins/vcsbase/vcsbase_dependencies.pri b/src/plugins/vcsbase/vcsbase_dependencies.pri
index 95a11af074..bff0f1dcf4 100644
--- a/src/plugins/vcsbase/vcsbase_dependencies.pri
+++ b/src/plugins/vcsbase/vcsbase_dependencies.pri
@@ -9,3 +9,5 @@ QTC_PLUGIN_DEPENDS += \
     texteditor \
     projectexplorer \
     cpptools
+QTC_PLUGIN_RECOMMENDS += \
+    cpaster
diff --git a/src/plugins/vcsbase/vcsbaseeditor.cpp b/src/plugins/vcsbase/vcsbaseeditor.cpp
index 8fe872caed..b5f3a848f4 100644
--- a/src/plugins/vcsbase/vcsbaseeditor.cpp
+++ b/src/plugins/vcsbase/vcsbaseeditor.cpp
@@ -40,6 +40,7 @@
 #include <coreplugin/vcsmanager.h>
 #include <coreplugin/patchtool.h>
 #include <coreplugin/editormanager/editormanager.h>
+#include <cpaster/codepasterservice.h>
 #include <extensionsystem/pluginmanager.h>
 #include <projectexplorer/editorconfiguration.h>
 #include <projectexplorer/projectexplorer.h>
@@ -953,9 +954,12 @@ void VcsBaseEditorWidget::contextMenuEvent(QContextMenuEvent *e)
     switch (d->m_parameters->type) {
     case LogOutput: // log might have diff
     case DiffOutput: {
-        menu->addSeparator();
-        connect(menu->addAction(tr("Send to CodePaster...")), &QAction::triggered,
-                this, &VcsBaseEditorWidget::slotPaste);
+        if (ExtensionSystem::PluginManager::getObject<CodePaster::Service>()) {
+            // optional code pasting service
+            menu->addSeparator();
+            connect(menu->addAction(tr("Send to CodePaster...")), &QAction::triggered,
+                    this, &VcsBaseEditorWidget::slotPaste);
+        }
         menu->addSeparator();
         // Apply/revert diff chunk.
         const DiffChunk chunk = diffChunk(cursorForPosition(e->pos()));
@@ -1472,14 +1476,9 @@ QStringList VcsBaseEditorWidget::annotationPreviousVersions(const QString &) con
 void VcsBaseEditorWidget::slotPaste()
 {
     // Retrieve service by soft dependency.
-    QObject *pasteService =
-            ExtensionSystem::PluginManager::getObjectByClassName(QLatin1String("CodePaster::CodePasterService"));
-    if (pasteService) {
-        QMetaObject::invokeMethod(pasteService, "postCurrentEditor");
-    } else {
-        QMessageBox::information(this, tr("Unable to Paste"),
-                                 tr("Code pasting services are not available."));
-    }
+    auto pasteService = ExtensionSystem::PluginManager::getObject<CodePaster::Service>();
+    QTC_ASSERT(pasteService, return);
+    pasteService->postCurrentEditor();
 }
 
 void VcsBaseEditorWidget::showProgressIndicator()