CppEditor: refactor FollowSymbol

Create an interface to get the ability to use
another FollowSymbol implementation

Change-Id: I5802f62523ff3ee47b8a14e487adf43edcb6c9b1
Reviewed-by: Nikolai Kosjar <nikolai.kosjar@qt.io>

src/plugins/clangcodemodel/clangcodemodel.pro

@@ -23,6 +23,7 @@ SOURCES += \
     clangeditordocumentprocessor.cpp \
     clangfixitoperation.cpp \
     clangfixitoperationsextractor.cpp \
+    clangfollowsymbol.cpp \
     clangfunctionhintmodel.cpp \
     clanghighlightingmarksreporter.cpp \
     clangmodelmanagersupport.cpp \
@@ -54,6 +55,7 @@ HEADERS += \
     clangeditordocumentprocessor.h \
     clangfixitoperation.h \
     clangfixitoperationsextractor.h \
+    clangfollowsymbol.h \
     clangfunctionhintmodel.h \
     clanghighlightingmarksreporter.h \
     clangisdiagnosticrelatedtolocation.h \

src/plugins/clangcodemodel/clangcodemodel.qbs

@@ -71,6 +71,8 @@ QtcPlugin {
         "clangfixitoperation.h",
         "clangfixitoperationsextractor.cpp",
         "clangfixitoperationsextractor.h",
+        "clangfollowsymbol.cpp",
+        "clangfollowsymbol.h",
         "clangfunctionhintmodel.cpp",
         "clangfunctionhintmodel.h",
         "clanghighlightingmarksreporter.cpp",

src/plugins/clangcodemodel/clangfollowsymbol.cpp

@@ -0,0 +1,83 @@
+/****************************************************************************
+**
+** Copyright (C) 2017 The Qt Company Ltd.
+** Contact: https://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 https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 3 as published by the Free Software
+** Foundation with exceptions as appearing in the file LICENSE.GPL3-EXCEPT
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-3.0.html.
+**
+****************************************************************************/
+
+#include "clangfollowsymbol.h"
+#include "clangeditordocumentprocessor.h"
+#include "texteditor/texteditor.h"
+#include "texteditor/convenience.h"
+
+namespace ClangCodeModel {
+namespace Internal {
+
+TextEditor::TextEditorWidget::Link ClangFollowSymbol::findLink(
+        const CppTools::CursorInEditor &data,
+        bool resolveTarget,
+        const CPlusPlus::Snapshot &,
+        const CPlusPlus::Document::Ptr &,
+        CppTools::SymbolFinder *,
+        bool)
+{
+    Link link;
+
+    int lineNumber = 0, positionInBlock = 0;
+    QTextCursor cursor = TextEditor::Convenience::wordStartCursor(data.cursor());
+    TextEditor::Convenience::convertPosition(cursor.document(), cursor.position(), &lineNumber,
+                                             &positionInBlock);
+    const unsigned line = lineNumber;
+    const unsigned column = positionInBlock + 1;
+
+    if (!resolveTarget)
+        return link;
+    ClangEditorDocumentProcessor *processor = ClangEditorDocumentProcessor::get(
+                data.filePath().toString());
+    if (!processor)
+        return link;
+
+    QFuture<CppTools::SymbolInfo> info
+            = processor->requestFollowSymbol(static_cast<int>(line),
+                                             static_cast<int>(column),
+                                             resolveTarget);
+    if (info.isCanceled())
+        return link;
+
+    while (!info.isFinished()) {
+        if (info.isCanceled())
+            return link;
+        QCoreApplication::processEvents(QEventLoop::ExcludeUserInputEvents);
+    }
+    CppTools::SymbolInfo result = info.result();
+
+    if (result.failedToFollow)
+        return link;
+
+    // We did not fail but the result is empty
+    if (result.fileName.isEmpty())
+        return link;
+
+    return Link(result.fileName, result.startLine, result.startColumn - 1);
+}
+
+} // namespace Internal
+} // namespace ClangCodeModel

src/plugins/clangcodemodel/clangfollowsymbol.h

@@ -0,0 +1,45 @@
+/****************************************************************************
+**
+** Copyright (C) 2017 The Qt Company Ltd.
+** Contact: https://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 https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 3 as published by the Free Software
+** Foundation with exceptions as appearing in the file LICENSE.GPL3-EXCEPT
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-3.0.html.
+**
+****************************************************************************/
+
+#pragma once
+
+#include <cpptools/followsymbolinterface.h>
+
+namespace ClangCodeModel {
+namespace Internal {
+
+class ClangFollowSymbol : public CppTools::FollowSymbolInterface
+{
+public:
+    Link findLink(const CppTools::CursorInEditor &data,
+                  bool resolveTarget,
+                  const CPlusPlus::Snapshot &,
+                  const CPlusPlus::Document::Ptr &,
+                  CppTools::SymbolFinder *,
+                  bool) override;
+};
+
+} // namespace Internal
+} // namespace ClangCodeModel

src/plugins/clangcodemodel/clangmodelmanagersupport.cpp

@@ -28,6 +28,7 @@
 #include "clangconstants.h"
 #include "clangeditordocumentprocessor.h"
 #include "clangutils.h"
+#include "clangfollowsymbol.h"
 
 #include <coreplugin/editormanager/editormanager.h>
 #include <cpptools/cppmodelmanager.h>
@@ -52,6 +53,12 @@ using namespace ClangCodeModel::Internal;
 
 static ModelManagerSupportClang *m_instance = 0;
 
+static bool useClangFollowSymbol()
+{
+    static bool use = qEnvironmentVariableIntValue("QTC_CLANG_FOLLOW_SYMBOL");
+    return use;
+}
+
 static CppTools::CppModelManager *cppModelManager()
 {
     return CppTools::CppModelManager::instance();
@@ -63,6 +70,9 @@ ModelManagerSupportClang::ModelManagerSupportClang()
     QTC_CHECK(!m_instance);
     m_instance = this;
 
+    if (useClangFollowSymbol())
+        m_followSymbol.reset(new ClangFollowSymbol);
+
     Core::EditorManager *editorManager = Core::EditorManager::instance();
     connect(editorManager, &Core::EditorManager::editorOpened,
             this, &ModelManagerSupportClang::onEditorOpened);
@@ -96,6 +106,11 @@ CppTools::CppCompletionAssistProvider *ModelManagerSupportClang::completionAssis
     return &m_completionAssistProvider;
 }
 
+CppTools::FollowSymbolInterface *ModelManagerSupportClang::followSymbolInterface()
+{
+    return m_followSymbol.get();
+}
+
 CppTools::BaseEditorDocumentProcessor *ModelManagerSupportClang::editorDocumentProcessor(
         TextEditor::TextDocument *baseTextDocument)
 {

src/plugins/clangcodemodel/clangmodelmanagersupport.h

@@ -33,6 +33,8 @@
 #include <QObject>
 #include <QScopedPointer>
 
+#include <memory>
+
 QT_BEGIN_NAMESPACE
 class QMenu;
 class QWidget;
@@ -44,6 +46,8 @@ namespace TextEditor { class TextEditorWidget; }
 namespace ClangCodeModel {
 namespace Internal {
 
+class ClangFollowSymbol;
+
 class ModelManagerSupportClang:
         public QObject,
         public CppTools::ModelManagerSupport
@@ -57,6 +61,7 @@ public:
     CppTools::CppCompletionAssistProvider *completionAssistProvider() override;
     CppTools::BaseEditorDocumentProcessor *editorDocumentProcessor(
                 TextEditor::TextDocument *baseTextDocument) override;
+    CppTools::FollowSymbolInterface *followSymbolInterface() override;
 
     IpcCommunicator &ipcCommunicator();
     QString dummyUiHeaderOnDiskDirPath() const;
@@ -100,6 +105,7 @@ private:
     UiHeaderOnDiskManager m_uiHeaderOnDiskManager;
     IpcCommunicator m_ipcCommunicator;
     ClangCompletionAssistProvider m_completionAssistProvider;
+    std::unique_ptr<ClangFollowSymbol> m_followSymbol;
 };
 
 class ModelManagerSupportProviderClang : public CppTools::ModelManagerSupportProvider