Clang: Provide highlighting for identifier under cursor

Change-Id: I80ffe23cbcc84ab7323124581d9dd6afbe974fd0
Reviewed-by: Marco Bubke <marco.bubke@qt.io>

src/plugins/clangcodemodel/clangbackendipcintegration.cpp

@@ -58,8 +58,11 @@
 #include <clangbackendipc/cmbunregistertranslationunitsforeditormessage.h>
 #include <clangbackendipc/cmbunregisterprojectsforeditormessage.h>
 #include <clangbackendipc/documentannotationschangedmessage.h>
+#include <clangbackendipc/referencesmessage.h>
+#include <clangbackendipc/requestreferencesmessage.h>
 #include <clangbackendipc/registerunsavedfilesforeditormessage.h>
 #include <clangbackendipc/requestdocumentannotations.h>
+#include <clangbackendipc/requestreferencesmessage.h>
 #include <clangbackendipc/filecontainer.h>
 #include <clangbackendipc/projectpartsdonotexistmessage.h>
 #include <clangbackendipc/translationunitdoesnotexistmessage.h>
@@ -74,6 +77,7 @@
 #include <QElapsedTimer>
 #include <QLoggingCategory>
 #include <QProcess>
+#include <QTextBlock>
 
 static Q_LOGGING_CATEGORY(log, "qtc.clangcodemodel.ipc")
 
@@ -150,6 +154,21 @@ void IpcReceiver::deleteProcessorsOfEditorWidget(TextEditor::TextEditorWidget *t
     }
 }
 
+QFuture<CppTools::CursorInfo> IpcReceiver::addExpectedReferencesMessage(quint64 ticket,
+                                                                        QTextDocument *textDocument)
+{
+    QTC_CHECK(textDocument);
+    QTC_CHECK(!m_referencesTable.contains(ticket));
+
+    QFutureInterface<CppTools::CursorInfo> futureInterface;
+    futureInterface.reportStarted();
+
+    const ReferencesEntry entry{futureInterface, textDocument};
+    m_referencesTable.insert(ticket, entry);
+
+    return futureInterface.future();
+}
+
 bool IpcReceiver::isExpectingCodeCompletedMessage() const
 {
     return !m_assistProcessorsTable.isEmpty();
@@ -205,6 +224,56 @@ void IpcReceiver::documentAnnotationsChanged(const DocumentAnnotationsChangedMes
     }
 }
 
+static
+CppTools::CursorInfo::Range toCursorInfoRange(const QTextDocument &textDocument,
+                                              const SourceRangeContainer &sourceRange)
+{
+    const SourceLocationContainer start = sourceRange.start();
+    const SourceLocationContainer end = sourceRange.end();
+    const unsigned length = end.column() - start.column();
+
+    const QTextBlock block = textDocument.findBlockByNumber(static_cast<int>(start.line()) - 1);
+    const int shift = ClangCodeModel::Utils::extraUtf8CharsShift(block.text(),
+                                                                 static_cast<int>(start.column()));
+    const uint column = start.column() - static_cast<uint>(shift);
+
+    return CppTools::CursorInfo::Range(start.line(), column, length);
+}
+
+static
+CppTools::CursorInfo toCursorInfo(const QTextDocument &textDocument,
+                                  const ReferencesMessage &message)
+{
+    CppTools::CursorInfo result;
+    const QVector<SourceRangeContainer> references = message.references();
+
+    result.areUseRangesForLocalVariable = message.isLocalVariable();
+    for (const SourceRangeContainer &reference : references)
+        result.useRanges.append(toCursorInfoRange(textDocument, reference));
+
+    result.useRanges.reserve(references.size());
+
+    return result;
+}
+
+void IpcReceiver::references(const ReferencesMessage &message)
+{
+    qCDebug(log) << "<<< ReferencesMessage with"
+                 << message.references().size() << "references";
+
+    const quint64 ticket = message.ticketNumber();
+    const ReferencesEntry entry = m_referencesTable.take(ticket);
+    QFutureInterface<CppTools::CursorInfo> futureInterface = entry.futureInterface;
+    QTC_CHECK(futureInterface != QFutureInterface<CppTools::CursorInfo>());
+
+    if (futureInterface.isCanceled())
+        return; // A new request was issued making this one outdated.
+
+    QTC_CHECK(entry.textDocument);
+    futureInterface.reportResult(toCursorInfo(*entry.textDocument, message));
+    futureInterface.reportFinished();
+}
+
 class IpcSender : public IpcSenderInterface
 {
 public:
@@ -222,6 +291,7 @@ public:
     void unregisterUnsavedFilesForEditor(const ClangBackEnd::UnregisterUnsavedFilesForEditorMessage &message) override;
     void completeCode(const ClangBackEnd::CompleteCodeMessage &message) override;
     void requestDocumentAnnotations(const ClangBackEnd::RequestDocumentAnnotationsMessage &message) override;
+    void requestReferences(const ClangBackEnd::RequestReferencesMessage &message) override;
     void updateVisibleTranslationUnits(const UpdateVisibleTranslationUnitsMessage &message) override;
 
 private:
@@ -298,6 +368,13 @@ void IpcSender::requestDocumentAnnotations(const RequestDocumentAnnotationsMessa
     m_connection.serverProxy().requestDocumentAnnotations(message);
 }
 
+void IpcSender::requestReferences(const RequestReferencesMessage &message)
+{
+    QTC_CHECK(m_connection.isConnected());
+    qCDebug(log) << ">>>" << message;
+    m_connection.serverProxy().requestReferences(message);
+}
+
 void IpcSender::updateVisibleTranslationUnits(const UpdateVisibleTranslationUnitsMessage &message)
 {
     QTC_CHECK(m_connection.isConnected());
@@ -318,6 +395,7 @@ public:
     void unregisterUnsavedFilesForEditor(const ClangBackEnd::UnregisterUnsavedFilesForEditorMessage &) override {}
     void completeCode(const ClangBackEnd::CompleteCodeMessage &) override {}
     void requestDocumentAnnotations(const ClangBackEnd::RequestDocumentAnnotationsMessage &) override {}
+    void requestReferences(const ClangBackEnd::RequestReferencesMessage &) override {}
     void updateVisibleTranslationUnits(const UpdateVisibleTranslationUnitsMessage &) override {}
 };
 
@@ -603,6 +681,18 @@ void IpcCommunicator::requestDocumentAnnotations(const FileContainer &fileContai
     m_ipcSender->requestDocumentAnnotations(message);
 }
 
+QFuture<CppTools::CursorInfo> IpcCommunicator::requestReferences(
+        const FileContainer &fileContainer,
+        quint32 line,
+        quint32 column,
+        QTextDocument *textDocument)
+{
+    const RequestReferencesMessage message(fileContainer, line, column);
+    m_ipcSender->requestReferences(message);
+
+    return m_ipcReceiver.addExpectedReferencesMessage(message.ticketNumber(), textDocument);
+}
+
 void IpcCommunicator::updateTranslationUnitWithRevisionCheck(Core::IDocument *document)
 {
     const auto textDocument = qobject_cast<TextDocument*>(document);

src/plugins/clangcodemodel/clangbackendipcintegration.h

@@ -32,8 +32,10 @@
 #include <clangbackendipc/clangcodemodelclientinterface.h>
 #include <clangbackendipc/projectpartcontainer.h>
 
+#include <QFuture>
 #include <QObject>
 #include <QSharedPointer>
+#include <QTextDocument>
 #include <QVector>
 
 #include <functional>
@@ -43,6 +45,10 @@ class IEditor;
 class IDocument;
 }
 
+namespace CppTools {
+class CursorInfo;
+}
+
 namespace ClangBackEnd {
 class DocumentAnnotationsChangedMessage;
 }
@@ -72,6 +78,9 @@ public:
     void deleteAndClearWaitingAssistProcessors();
     void deleteProcessorsOfEditorWidget(TextEditor::TextEditorWidget *textEditorWidget);
 
+    QFuture<CppTools::CursorInfo> addExpectedReferencesMessage(quint64 ticket,
+                                                               QTextDocument *textDocument);
+
     bool isExpectingCodeCompletedMessage() const;
 
 private:
@@ -80,6 +89,7 @@ private:
     void codeCompleted(const ClangBackEnd::CodeCompletedMessage &message) override;
 
     void documentAnnotationsChanged(const ClangBackEnd::DocumentAnnotationsChangedMessage &message) override;
+    void references(const ClangBackEnd::ReferencesMessage &message) override;
 
     void translationUnitDoesNotExist(const ClangBackEnd::TranslationUnitDoesNotExistMessage &) override {}
     void projectPartsDoNotExist(const ClangBackEnd::ProjectPartsDoNotExistMessage &) override {}
@@ -87,6 +97,12 @@ private:
 private:
     AliveHandler m_aliveHandler;
     QHash<quint64, ClangCompletionAssistProcessor *> m_assistProcessorsTable;
+
+    struct ReferencesEntry {
+        QFutureInterface<CppTools::CursorInfo> futureInterface;
+        QTextDocument *textDocument = nullptr;
+    };
+    QHash<quint64, ReferencesEntry> m_referencesTable;
     const bool m_printAliveMessage = false;
 };
 
@@ -105,6 +121,7 @@ public:
     virtual void unregisterUnsavedFilesForEditor(const ClangBackEnd::UnregisterUnsavedFilesForEditorMessage &message) = 0;
     virtual void completeCode(const ClangBackEnd::CompleteCodeMessage &message) = 0;
     virtual void requestDocumentAnnotations(const ClangBackEnd::RequestDocumentAnnotationsMessage &message) = 0;
+    virtual void requestReferences(const ClangBackEnd::RequestReferencesMessage &message) = 0;
     virtual void updateVisibleTranslationUnits(const ClangBackEnd::UpdateVisibleTranslationUnitsMessage &message) = 0;
 };
 
@@ -114,6 +131,7 @@ class IpcCommunicator : public QObject
 
 public:
     using Ptr = QSharedPointer<IpcCommunicator>;
+    using FileContainer = ClangBackEnd::FileContainer;
     using FileContainers = QVector<ClangBackEnd::FileContainer>;
     using ProjectPartContainers = QVector<ClangBackEnd::ProjectPartContainer>;
 
@@ -129,6 +147,9 @@ public:
     void registerUnsavedFilesForEditor(const FileContainers &fileContainers);
     void unregisterUnsavedFilesForEditor(const FileContainers &fileContainers);
     void requestDocumentAnnotations(const ClangBackEnd::FileContainer &fileContainer);
+    QFuture<CppTools::CursorInfo> requestReferences(const FileContainer &fileContainer,
+                                                    quint32 line,
+                                                    quint32 column, QTextDocument *textDocument);
     void completeCode(ClangCompletionAssistProcessor *assistProcessor, const QString &filePath,
                       quint32 line,
                       quint32 column,

src/plugins/clangcodemodel/clangeditordocumentprocessor.cpp

@@ -68,6 +68,7 @@ ClangEditorDocumentProcessor::ClangEditorDocumentProcessor(
         IpcCommunicator &ipcCommunicator,
         TextEditor::TextDocument *document)
     : BaseEditorDocumentProcessor(document->document(), document->filePath().toString())
+    , m_document(*document)
     , m_diagnosticManager(document)
     , m_ipcCommunicator(ipcCommunicator)
     , m_parser(new ClangEditorDocumentParser(document->filePath().toString()))
@@ -287,10 +288,48 @@ void ClangEditorDocumentProcessor::setParserConfig(
     m_builtinProcessor.parser()->setConfiguration(config);
 }
 
+static bool isCursorOnIdentifier(const QTextCursor &textCursor)
+{
+    QTextDocument *document = textCursor.document();
+    return CppTools::isValidIdentifierChar(document->characterAt(textCursor.position()));
+}
+
+static QFuture<CppTools::CursorInfo> defaultCursorInfoFuture()
+{
+    QFutureInterface<CppTools::CursorInfo> futureInterface;
+    futureInterface.reportResult(CppTools::CursorInfo());
+    futureInterface.reportFinished();
+
+    return futureInterface.future();
+}
+
+static bool convertPosition(const QTextCursor &textCursor, int *line, int *column)
+{
+    const bool converted = TextEditor::Convenience::convertPosition(textCursor.document(),
+                                                                    textCursor.position(),
+                                                                    line,
+                                                                    column);
+    QTC_CHECK(converted);
+    return converted;
+}
+
 QFuture<CppTools::CursorInfo>
 ClangEditorDocumentProcessor::cursorInfo(const CppTools::CursorInfoParams &params)
 {
-    return m_builtinProcessor.cursorInfo(params);
+    int line, column;
+    convertPosition(params.textCursor, &line, &column);
+    ++column; // for 1-based columns
+
+    if (!isCursorOnIdentifier(params.textCursor))
+        return defaultCursorInfoFuture();
+
+    const QTextBlock block = params.textCursor.document()->findBlockByNumber(line - 1);
+    column += ClangCodeModel::Utils::extraUtf8CharsShift(block.text(), column);
+
+    return m_ipcCommunicator.requestReferences(simpleFileContainer(),
+                                               static_cast<quint32>(line),
+                                               static_cast<quint32>(column),
+                                               textDocument());
 }
 
 ClangBackEnd::FileContainer ClangEditorDocumentProcessor::fileContainerWithArguments() const
@@ -396,6 +435,15 @@ ClangEditorDocumentProcessor::creatorForHeaderErrorDiagnosticWidget(
     };
 }
 
+ClangBackEnd::FileContainer ClangEditorDocumentProcessor::simpleFileContainer() const
+{
+    Utf8String projectPartId;
+    if (m_projectPart)
+        projectPartId = m_projectPart->id();
+
+    return ClangBackEnd::FileContainer(filePath(), projectPartId, Utf8String(), false, revision());
+}
+
 static CppTools::ProjectPart projectPartForLanguageOption(CppTools::ProjectPart *projectPart)
 {
     if (projectPart)

src/plugins/clangcodemodel/clangeditordocumentprocessor.h

@@ -101,12 +101,14 @@ private:
     void requestDocumentAnnotations(const QString &projectpartId);
     HeaderErrorDiagnosticWidgetCreator creatorForHeaderErrorDiagnosticWidget(
             const ClangBackEnd::DiagnosticContainer &firstHeaderErrorDiagnostic);
+    ClangBackEnd::FileContainer simpleFileContainer() const;
     ClangBackEnd::FileContainer fileContainerWithArguments(CppTools::ProjectPart *projectPart) const;
     ClangBackEnd::FileContainer fileContainerWithArgumentsAndDocumentContent(
             CppTools::ProjectPart *projectPart) const;
     ClangBackEnd::FileContainer fileContainerWithDocumentContent(const QString &projectpartId) const;
 
 private:
+    TextEditor::TextDocument &m_document;
     ClangDiagnosticManager m_diagnosticManager;
     IpcCommunicator &m_ipcCommunicator;
     QSharedPointer<ClangEditorDocumentParser> m_parser;

src/plugins/clangcodemodel/test/clangcodecompletion_test.cpp

@@ -325,6 +325,10 @@ QString toString(const RequestDocumentAnnotationsMessage &)
     return QStringLiteral("RequestDocumentAnnotationsMessage\n");
 }
 
+QString toString(const RequestReferencesMessage &)
+{
+    return QStringLiteral("RequestReferencesMessage\n");
+}
 
 QString toString(const UpdateVisibleTranslationUnitsMessage &)
 {
@@ -364,6 +368,9 @@ public:
     void requestDocumentAnnotations(const RequestDocumentAnnotationsMessage &message) override
     { senderLog.append(toString(message)); }
 
+    void requestReferences(const RequestReferencesMessage &message) override
+    { senderLog.append(toString(message)); }
+
     void updateVisibleTranslationUnits(const UpdateVisibleTranslationUnitsMessage &message) override
     { senderLog.append(toString(message)); }