Remove support for ghc-mod

ghc-mod is no longer active and doesn't even compile against newer
GHC versions.
Use haskell-ide-engine and Qt Creator's language protocol client
instead.

Change-Id: I5776ec8375c732b8066d09e629148ae222e981c5
Reviewed-by: hjk <hjk@qt.io>

21 files changed, 1 insertions, 1647 deletions

diff --git a/plugins/haskell/CMakeLists.txt b/plugins/haskell/CMakeLists.txt
index d2e08af..1b5ec8f 100644
--- a/plugins/haskell/CMakeLists.txt
+++ b/plugins/haskell/CMakeLists.txt
@@ -6,19 +6,12 @@ add_qtc_plugin(Haskell
     QtCreator::Core QtCreator::TextEditor QtCreator::ProjectExplorer
   DEPENDS Qt5::Widgets
   SOURCES
-    filecache.cpp filecache.h
-    followsymbol.cpp followsymbol.h
-    ghcmod.cpp ghcmod.h
     haskell.qrc
     haskell_global.h
     haskellbuildconfiguration.cpp haskellbuildconfiguration.h
-    haskellcompletionassist.cpp haskellcompletionassist.h
     haskellconstants.h
-    haskelldocument.cpp haskelldocument.h
     haskelleditorfactory.cpp haskelleditorfactory.h
-    haskelleditorwidget.cpp haskelleditorwidget.h
     haskellhighlighter.cpp haskellhighlighter.h
-    haskellhoverhandler.cpp haskellhoverhandler.h
     haskellmanager.cpp haskellmanager.h
     haskellplugin.cpp haskellplugin.h
     haskellproject.cpp haskellproject.h
diff --git a/plugins/haskell/filecache.cpp b/plugins/haskell/filecache.cpp
deleted file mode 100644
index 5d931c9..0000000
--- a/plugins/haskell/filecache.cpp
+++ /dev/null
@@ -1,139 +0,0 @@
-/****************************************************************************
-**
-** 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 "filecache.h"
-
-#include <coreplugin/idocument.h>
-#include <texteditor/textdocument.h>
-#include <utils/algorithm.h>
-
-#include <QFile>
-#include <QLoggingCategory>
-#include <QTemporaryFile>
-#include <QTextDocument>
-
-Q_LOGGING_CATEGORY(cacheLog, "qtc.haskell.filecache", QtWarningMsg)
-
-using namespace Core;
-using namespace TextEditor;
-using namespace Utils;
-
-namespace Haskell {
-namespace Internal {
-
-FileCache::FileCache(const QString &id,
-                     const std::function<QList<Core::IDocument *>()> &documentsToUpdate)
-    : m_tempDir(id),
-      m_documentsToUpdate(documentsToUpdate)
-{
-    qCDebug(cacheLog) << "creating cache path at" << m_tempDir.path();
-}
-
-
-void FileCache::update()
-{
-    const QList<IDocument *> documents = m_documentsToUpdate();
-    for (IDocument *document : documents) {
-        const Utils::FilePath filePath = document->filePath();
-        if (m_fileMap.contains(filePath)) {
-            // update the existing cached file
-            // check revision if possible
-            if (auto textDocument = qobject_cast<TextDocument *>(document)) {
-                if (m_fileRevision.value(filePath) != textDocument->document()->revision())
-                    writeFile(document);
-            } else {
-                writeFile(document);
-            }
-        } else {
-            // save file if it is modified
-            if (document->isModified())
-                writeFile(document);
-        }
-    }
-    cleanUp(documents);
-}
-
-QHash<FilePath, FilePath> FileCache::fileMap() const
-{
-    return m_fileMap;
-}
-
-void FileCache::writeFile(IDocument *document)
-{
-    FilePath cacheFilePath = m_fileMap.value(document->filePath());
-    if (cacheFilePath.isEmpty()) {
-        cacheFilePath = createCacheFile(document->filePath());
-        m_fileMap.insert(document->filePath(), cacheFilePath);
-    }
-    qCDebug(cacheLog) << "writing" << cacheFilePath;
-    if (auto baseTextDocument = qobject_cast<BaseTextDocument *>(document)) {
-        QString errorMessage;
-        if (baseTextDocument->write(cacheFilePath.toString(),
-                                    QString::fromUtf8(baseTextDocument->contents()),
-                                    &errorMessage)) {
-            if (auto textDocument = qobject_cast<TextDocument *>(document)) {
-                m_fileRevision.insert(document->filePath(), textDocument->document()->revision());
-            } else {
-                m_fileRevision.insert(document->filePath(), -1);
-            }
-        } else {
-            qCDebug(cacheLog) << "!!! writing file failed:" << errorMessage;
-        }
-
-    } else {
-        QFile file(cacheFilePath.toString());
-        if (file.open(QIODevice::WriteOnly)) {
-            file.write(document->contents());
-        } else {
-            qCDebug(cacheLog) << "!!! opening file for writing failed";
-        }
-    }
-}
-
-void FileCache::cleanUp(const QList<IDocument *> &documents)
-{
-    const QSet<FilePath> files = Utils::transform<QSet>(documents, &IDocument::filePath);
-    auto it = QMutableHashIterator<FilePath, FilePath>(m_fileMap);
-    while (it.hasNext()) {
-        it.next();
-        if (!files.contains(it.key())) {
-            qCDebug(cacheLog) << "deleting" << it.value();
-            QFile::remove(it.value().toString());
-            m_fileRevision.remove(it.key());
-            it.remove();
-        }
-    }
-}
-
-FilePath FileCache::createCacheFile(const FilePath &filePath)
-{
-    QTemporaryFile tempFile(m_tempDir.path() + "/XXXXXX-" + filePath.fileName());
-    tempFile.setAutoRemove(false);
-    tempFile.open();
-    return FilePath::fromString(tempFile.fileName());
-}
-
-} // namespace Internal
-} // namespace Haskell
diff --git a/plugins/haskell/filecache.h b/plugins/haskell/filecache.h
deleted file mode 100644
index 3c53d40..0000000
--- a/plugins/haskell/filecache.h
+++ /dev/null
@@ -1,61 +0,0 @@
-/****************************************************************************
-**
-** 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 <utils/fileutils.h>
-#include <utils/temporarydirectory.h>
-
-#include <QHash>
-
-#include <functional>
-
-namespace Core { class IDocument; }
-
-namespace Haskell {
-namespace Internal {
-
-class FileCache
-{
-public:
-    FileCache(const QString &id,
-              const std::function<QList<Core::IDocument *>()> &documentsToUpdate);
-
-    void update();
-    QHash<Utils::FilePath, Utils::FilePath> fileMap() const;
-
-private:
-    void writeFile(Core::IDocument *document);
-    void cleanUp(const QList<Core::IDocument *> &documents);
-    Utils::FilePath createCacheFile(const Utils::FilePath &filePath);
-
-    Utils::TemporaryDirectory m_tempDir;
-    QHash<Utils::FilePath, Utils::FilePath> m_fileMap;
-    QHash<Utils::FilePath, int> m_fileRevision;
-    std::function<QList<Core::IDocument *>()> m_documentsToUpdate;
-};
-
-} // namespace Internal
-} // namespace Haskell
diff --git a/plugins/haskell/followsymbol.cpp b/plugins/haskell/followsymbol.cpp
deleted file mode 100644
index ab32614..0000000
--- a/plugins/haskell/followsymbol.cpp
+++ /dev/null
@@ -1,141 +0,0 @@
-/****************************************************************************
-**
-** 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 "followsymbol.h"
-
-#include "haskelleditorwidget.h"
-#include "haskellmanager.h"
-#include "haskelltokenizer.h"
-
-#include <coreplugin/editormanager/editormanager.h>
-#include <texteditor/codeassist/assistinterface.h>
-#include <texteditor/codeassist/assistproposalitem.h>
-#include <texteditor/codeassist/genericproposal.h>
-#include <texteditor/codeassist/genericproposalmodel.h>
-
-#include <utils/qtcassert.h>
-
-using namespace TextEditor;
-using namespace Utils;
-
-namespace Haskell {
-namespace Internal {
-
-IAssistProvider::RunType FollowSymbolAssistProvider::runType() const
-{
-    return AsynchronousWithThread;
-}
-
-IAssistProcessor *FollowSymbolAssistProvider::createProcessor() const
-{
-    return new FollowSymbolAssistProcessor(m_inNextSplit);
-}
-
-void FollowSymbolAssistProvider::setOpenInNextSplit(bool inNextSplit)
-{
-    m_inNextSplit = inNextSplit;
-}
-
-FollowSymbolAssistProcessor::FollowSymbolAssistProcessor(bool inNextSplit)
-    : m_inNextSplit(inNextSplit)
-{
-}
-
-IAssistProposal *FollowSymbolAssistProcessor::immediateProposal(const AssistInterface *interface)
-{
-    int line, column;
-    const optional<Token> symbol
-            = HaskellEditorWidget::symbolAt(interface->textDocument(), interface->position(),
-                                            &line, &column);
-    QTC_ASSERT(symbol, return nullptr); // should have been checked before
-    const auto filePath = FilePath::fromString(interface->fileName());
-    m_ghcmod = HaskellManager::ghcModForFile(filePath);
-    m_symbolFuture = m_ghcmod->findSymbol(filePath, symbol->text.toString());
-
-    auto item = new AssistProposalItem();
-    item->setText(HaskellManager::trLookingUp(symbol->text.toString()));
-    item->setData(QString());
-    item->setOrder(-1000);
-
-    const QList<TextEditor::AssistProposalItemInterface *> list = {item};
-    auto proposal = new GenericProposal(interface->position(), list);
-    proposal->setFragile(true);
-    return proposal;
-}
-
-IAssistProposal *FollowSymbolAssistProcessor::perform(const AssistInterface *interface)
-{
-    const int position = interface->position();
-    delete interface;
-    const SymbolInfoOrError info = m_symbolFuture.result();
-    auto item = new FollowSymbolAssistProposalItem(m_ghcmod->basePath(), info, m_inNextSplit);
-    return new InstantProposal(position, {item});
-}
-
-FollowSymbolAssistProposalItem::FollowSymbolAssistProposalItem(const FilePath &basePath,
-                                                               const SymbolInfoOrError &info,
-                                                               bool inNextSplit)
-    : m_basePath(basePath),
-      m_inNextSplit(inNextSplit)
-{
-    const SymbolInfo *info_p = Utils::get_if<SymbolInfo>(&info);
-    if (info_p && !info_p->file.isEmpty()) {
-        m_info = info;
-        setText(m_basePath.toString() + '/' + info_p->file.toString());
-    }
-}
-
-void FollowSymbolAssistProposalItem::apply(TextDocumentManipulatorInterface &, int) const
-{
-    const SymbolInfo *info_p = Utils::get_if<SymbolInfo>(&m_info);
-    if (info_p)
-        Core::EditorManager::openEditorAt(m_basePath.toString() + '/' + info_p->file.toString(),
-                                          info_p->line, info_p->col - 1, Core::Id(),
-                                          m_inNextSplit ? Core::EditorManager::OpenInOtherSplit
-                                                        : Core::EditorManager::NoFlags);
-}
-
-void InstantActivationProposalWidget::showProposal(const QString &prefix)
-{
-    if (model() && model()->size() == 1) {
-        emit proposalItemActivated(model()->proposalItem(0));
-        deleteLater();
-        return;
-    }
-    GenericProposalWidget::showProposal(prefix);
-}
-
-InstantProposal::InstantProposal(int cursorPos, const QList<AssistProposalItemInterface *> &items)
-    : GenericProposal(cursorPos, items)
-{
-}
-
-IAssistProposalWidget *InstantProposal::createWidget() const
-{
-    return new InstantActivationProposalWidget();
-}
-
-} // namespace Internal
-} // namespace Haskell
diff --git a/plugins/haskell/followsymbol.h b/plugins/haskell/followsymbol.h
deleted file mode 100644
index a4f9051..0000000
--- a/plugins/haskell/followsymbol.h
+++ /dev/null
@@ -1,94 +0,0 @@
-/****************************************************************************
-**
-** 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 "ghcmod.h"
-
-#include <texteditor/codeassist/assistproposalitem.h>
-#include <texteditor/codeassist/genericproposal.h>
-#include <texteditor/codeassist/genericproposalwidget.h>
-#include <texteditor/codeassist/iassistprocessor.h>
-#include <texteditor/codeassist/iassistprovider.h>
-
-namespace Haskell {
-namespace Internal {
-
-class FollowSymbolAssistProposalItem : public TextEditor::AssistProposalItem
-{
-public:
-    FollowSymbolAssistProposalItem(const Utils::FilePath &basePath,
-                                   const SymbolInfoOrError &info,
-                                   bool inNextSplit);
-
-    void apply(TextEditor::TextDocumentManipulatorInterface &, int) const override;
-
-private:
-    Utils::FilePath m_basePath;
-    SymbolInfoOrError m_info;
-    bool m_inNextSplit;
-};
-
-class InstantActivationProposalWidget : public TextEditor::GenericProposalWidget
-{
-protected:
-    void showProposal(const QString &prefix) override;
-};
-
-class InstantProposal : public TextEditor::GenericProposal
-{
-public:
-    InstantProposal(int cursorPos, const QList<TextEditor::AssistProposalItemInterface *> &items);
-
-    TextEditor::IAssistProposalWidget *createWidget() const override;
-};
-
-class FollowSymbolAssistProvider : public TextEditor::IAssistProvider
-{
-public:
-    RunType runType() const override;
-    TextEditor::IAssistProcessor *createProcessor() const override;
-    void setOpenInNextSplit(bool inNextSplit);
-
-private:
-    bool m_inNextSplit = false;
-};
-
-class FollowSymbolAssistProcessor : public TextEditor::IAssistProcessor
-{
-public:
-    FollowSymbolAssistProcessor(bool inNextSplit);
-
-    TextEditor::IAssistProposal *immediateProposal(const TextEditor::AssistInterface *interface) override;
-    TextEditor::IAssistProposal *perform(const TextEditor::AssistInterface *interface) override;
-
-private:
-    std::shared_ptr<AsyncGhcMod> m_ghcmod;
-    QFuture<SymbolInfoOrError> m_symbolFuture;
-    bool m_inNextSplit;
-};
-
-} // namespace Internal
-} // namespace Haskell
diff --git a/plugins/haskell/ghcmod.cpp b/plugins/haskell/ghcmod.cpp
deleted file mode 100644
index 1ca7713..0000000
--- a/plugins/haskell/ghcmod.cpp
+++ /dev/null
@@ -1,408 +0,0 @@
-/****************************************************************************
-**
-** 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 "ghcmod.h"
-
-#include <coreplugin/editormanager/documentmodel.h>
-#include <coreplugin/idocument.h>
-#include <utils/algorithm.h>
-#include <utils/environment.h>
-#include <utils/qtcassert.h>
-
-#include <QFileInfo>
-#include <QFutureWatcher>
-#include <QLoggingCategory>
-#include <QMetaObject>
-#include <QMutexLocker>
-#include <QProcess>
-#include <QRegularExpression>
-#include <QTime>
-#include <QTimer>
-
-#include <functional>
-
-Q_LOGGING_CATEGORY(ghcModLog, "qtc.haskell.ghcmod", QtWarningMsg)
-Q_LOGGING_CATEGORY(asyncGhcModLog, "qtc.haskell.ghcmod.async", QtWarningMsg)
-
-// TODO do not hardcode
-const int kTimeoutMS = 10 * 1000;
-
-using namespace Utils;
-
-namespace Haskell {
-namespace Internal {
-
-FilePath GhcMod::m_stackExecutable = Utils::FilePath::fromString("stack");
-QMutex GhcMod::m_mutex;
-
-GhcMod::GhcMod(const Utils::FilePath &path)
-    : m_path(path)
-{
-}
-
-GhcMod::~GhcMod()
-{
-    shutdown();
-}
-
-FilePath GhcMod::basePath() const
-{
-    return m_path;
-}
-
-void GhcMod::setFileMap(const QHash<FilePath, FilePath> &fileMap)
-{
-    if (fileMap != m_fileMap) {
-        log("setting new file map");
-        m_fileMap = fileMap;
-        shutdown();
-    }
-}
-
-static QString toUnicode(QByteArray data)
-{
-    // clean zero bytes which let QString think that the string ends there
-    data.replace('\x0', QByteArray());
-    return QString::fromUtf8(data);
-}
-
-SymbolInfoOrError GhcMod::findSymbol(const FilePath &filePath, const QString &symbol)
-{
-    return parseFindSymbol(runFindSymbol(filePath, symbol));
-}
-
-QStringOrError GhcMod::typeInfo(const FilePath &filePath, int line, int col)
-{
-    return parseTypeInfo(runTypeInfo(filePath, line, col));
-}
-
-static QStringList fileMapArgs(const QHash<FilePath, FilePath> &map)
-{
-    QStringList result;
-    const auto end = map.cend();
-    for (auto it = map.cbegin(); it != end; ++it)
-        result << "--map-file" << it.key().toString() + "=" + it.value().toString();
-    return result;
-}
-
-Utils::optional<Error> GhcMod::ensureStarted()
-{
-    m_mutex.lock();
-    const FilePath plainStackExecutable = m_stackExecutable;
-    m_mutex.unlock();
-    Environment env = Environment::systemEnvironment();
-    const FilePath stackExecutable = env.searchInPath(plainStackExecutable.toString());
-    if (m_process) {
-        if (m_process->state() == QProcess::NotRunning) {
-            log("is no longer running");
-            m_process.reset();
-        } else if (FilePath::fromString(m_process->program()) != stackExecutable) {
-            log("stack settings changed");
-            shutdown();
-        }
-    }
-    if (m_process)
-        return Utils::nullopt;
-    log("starting");
-    // for ghc-mod finding stack back:
-    env.prependOrSetPath(stackExecutable.toFileInfo().absolutePath());
-    m_process.reset(new QProcess);
-    m_process->setWorkingDirectory(m_path.toString());
-    m_process->setEnvironment(env.toStringList());
-    m_process->start(stackExecutable.toString(),
-                     QStringList{"exec", "ghc-mod", "--"} + fileMapArgs(m_fileMap)
-                     << "legacy-interactive");
-    if (!m_process->waitForStarted(kTimeoutMS)) {
-        log("failed to start");
-        m_process.reset();
-        return Error({Error::Type::FailedToStartStack, plainStackExecutable.toUserOutput()});
-    }
-    log("started");
-    m_process->setReadChannel(QProcess::StandardOutput);
-    return Utils::nullopt;
-}
-
-void GhcMod::shutdown()
-{
-    if (!m_process)
-        return;
-    log("shutting down");
-    m_process->write("\n");
-    m_process->closeWriteChannel();
-    m_process->waitForFinished(300);
-    m_process.reset();
-}
-
-void GhcMod::log(const QString &message)
-{
-    qCDebug(ghcModLog) << "ghcmod for" << m_path.toString() << ":" << qPrintable(message);
-}
-
-QByteArrayOrError GhcMod::runQuery(const QString &query)
-{
-    const Utils::optional<Error> error = ensureStarted();
-    if (error)
-        return error.value();
-    log("query \"" + query + "\"");
-    m_process->write(query.toUtf8() + "\n");
-    bool ok = false;
-    QByteArray response;
-    QTime readTime;
-    readTime.start();
-    while (!ok && readTime.elapsed() < kTimeoutMS) {
-        m_process->waitForReadyRead(kTimeoutMS - readTime.elapsed() + 10);
-        response += m_process->read(2048);
-        ok = response.endsWith("OK\n") || response.endsWith("OK\r\n");
-    }
-    if (ghcModLog().isDebugEnabled())
-        qCDebug(ghcModLog) << "response" << QTextCodec::codecForLocale()->toUnicode(response);
-    if (!ok) {
-        log("failed");
-        shutdown();
-        return Error({Error::Type::Other, QString()});
-    }
-    log("success");
-    // convert to unix line endings
-    response.replace("\r\n", "\n");
-    response.chop(3); // cut off "OK\n"
-    return response;
-}
-
-QByteArrayOrError GhcMod::runFindSymbol(const FilePath &filePath, const QString &symbol)
-{
-    return runQuery(QString("info %1 %2").arg(filePath.toString()) // TODO toNative? quoting?
-                    .arg(symbol));
-}
-
-QByteArrayOrError GhcMod::runTypeInfo(const FilePath &filePath, int line, int col)
-{
-    return runQuery(QString("type %1 %2 %3").arg(filePath.toString()) // TODO toNative? quoting?
-                    .arg(line)
-                    .arg(col + 1));
-}
-
-SymbolInfoOrError GhcMod::parseFindSymbol(const QByteArrayOrError &response)
-{
-    QRegularExpression infoRegEx("^\\s*(.*?)\\s+--\\sDefined ((at (.+?)(:(\\d+):(\\d+))?)|(in ‘(.+)’.*))$");
-    const QByteArray *bytes = Utils::get_if<QByteArray>(&response);
-    if (!bytes)
-        return Utils::get<Error>(response);
-    SymbolInfo info;
-    bool hasFileOrModule = false;
-    const QString str = toUnicode(QByteArray(*bytes).replace('\x0', '\n'));
-    for (const QString &line : str.split('\n')) {
-        if (hasFileOrModule) {
-            info.additionalInfo += line;
-        } else {
-            QRegularExpressionMatch result = infoRegEx.match(line);
-            if (result.hasMatch()) {
-                hasFileOrModule = true;
-                info.definition += result.captured(1);
-                if (result.lastCapturedIndex() == 7) { // Defined at <file:line:col>
-                    info.file = FilePath::fromString(result.captured(4));
-                    bool ok;
-                    int num = result.captured(6).toInt(&ok);
-                    if (ok)
-                        info.line = num;
-                    num = result.captured(7).toInt(&ok);
-                    if (ok)
-                        info.col = num;
-                } else if (result.lastCapturedIndex() == 9) { // Defined in <module>
-                    info.module = result.captured(9);
-                }
-            } else {
-                info.definition += line;
-            }
-        }
-    }
-    if (hasFileOrModule)
-        return info;
-    return Error({Error::Type::Other, QString()});
-}
-
-QStringOrError GhcMod::parseTypeInfo(const QByteArrayOrError &response)
-{
-    QRegularExpression typeRegEx("^\\d+\\s+\\d+\\s+\\d+\\s+\\d+\\s+\"(.*)\"$",
-                                 QRegularExpression::MultilineOption);
-    const QByteArray *bytes = Utils::get_if<QByteArray>(&response);
-    if (!bytes)
-        return Utils::get<Error>(response);
-    QRegularExpressionMatch result = typeRegEx.match(toUnicode(*bytes));
-    if (result.hasMatch())
-        return result.captured(1);
-    return Error({Error::Type::Other, QString()});
-}
-
-void GhcMod::setStackExecutable(const FilePath &filePath)
-{
-    QMutexLocker lock(&m_mutex);
-    m_stackExecutable = filePath;
-}
-
-static QList<Core::IDocument *> getOpenDocuments(const FilePath &path)
-{
-    return Utils::filtered(Core::DocumentModel::openedDocuments(), [path] (Core::IDocument *doc) {
-        return path.isEmpty() || doc->filePath().isChildOf(path);
-    });
-}
-
-AsyncGhcMod::AsyncGhcMod(const FilePath &path)
-    : m_ghcmod(path),
-      m_fileCache("haskell", std::bind(getOpenDocuments, path))
-{
-    qCDebug(asyncGhcModLog) << "starting thread for" << m_ghcmod.basePath().toString();
-    m_thread.start();
-    m_threadTarget.moveToThread(&m_thread);
-}
-
-AsyncGhcMod::~AsyncGhcMod()
-{
-    qCDebug(asyncGhcModLog) << "stopping thread for" << m_ghcmod.basePath().toString();
-    m_mutex.lock();
-    for (Operation &op : m_queue)
-        op.fi.cancel();
-    m_queue.clear();
-    m_mutex.unlock();
-    m_thread.quit();
-    m_thread.wait();
-}
-
-FilePath AsyncGhcMod::basePath() const
-{
-    return m_ghcmod.basePath();
-}
-
-template <typename Result>
-QFuture<Result> createFuture(AsyncGhcMod::Operation op,
-                             const std::function<Result(const QByteArrayOrError &)> &postOp)
-{
-    auto fi = new QFutureInterface<Result>;
-    fi->reportStarted();
-
-    // propagate inner events to outside future
-    auto opWatcher = new QFutureWatcher<QByteArrayOrError>();
-    QObject::connect(opWatcher, &QFutureWatcherBase::canceled, [fi] { fi->cancel(); });
-    QObject::connect(opWatcher, &QFutureWatcherBase::finished, opWatcher, &QObject::deleteLater);
-    QObject::connect(opWatcher, &QFutureWatcherBase::finished, [fi] {
-        fi->reportFinished();
-        delete fi;
-    });
-    QObject::connect(opWatcher, &QFutureWatcherBase::resultReadyAt,
-                     [fi, opWatcher, postOp](int index) {
-                         fi->reportResult(postOp(opWatcher->future().resultAt(index)));
-                     });
-    opWatcher->setFuture(op.fi.future());
-
-    // propagate cancel from outer future to inner future
-    auto fiWatcher = new QFutureWatcher<Result>();
-    QObject::connect(fiWatcher, &QFutureWatcherBase::canceled, [op] { op.fi.cancel(); });
-    QObject::connect(fiWatcher, &QFutureWatcherBase::finished, fiWatcher, &QObject::deleteLater);
-    fiWatcher->setFuture(fi->future());
-
-    return fi->future();
-}
-
-/*!
-    Asynchronously looks up the \a symbol in the context of \a filePath.
-
-    Returns a QFuture handle for the asynchronous operation. You may not block the main event loop
-    while waiting for it to finish - doing so will result in a deadlock.
-*/
-QFuture<SymbolInfoOrError> AsyncGhcMod::findSymbol(const FilePath &filePath,
-                                                             const QString &symbol)
-{
-    QMutexLocker lock(&m_mutex);
-    Operation op([this, filePath, symbol] { return m_ghcmod.runFindSymbol(filePath, symbol); });
-    m_queue.append(op);
-    QTimer::singleShot(0, &m_threadTarget, [this] { reduceQueue(); });
-    return createFuture<SymbolInfoOrError>(op, &GhcMod::parseFindSymbol);
-}
-
-/*!
-    Asynchronously looks up the type at \a line and \a col in \a filePath.
-
-    Returns a QFuture handle for the asynchronous operation. You may not block the main event loop
-    while waiting for it to finish - doing so will result in a deadlock.
-*/
-QFuture<QStringOrError> AsyncGhcMod::typeInfo(const FilePath &filePath, int line, int col)
-{
-    QMutexLocker lock(&m_mutex);
-    Operation op([this, filePath, line, col] { return m_ghcmod.runTypeInfo(filePath, line, col); });
-    m_queue.append(op);
-    QTimer::singleShot(0, &m_threadTarget, [this] { reduceQueue(); });
-    return createFuture<QStringOrError>(op, &GhcMod::parseTypeInfo);
-}
-
-/*!
-    Synchronously runs an update of the cache of modified files.
-    This must be run on the main thread.
-
-    \internal
-*/
-void AsyncGhcMod::updateCache()
-{
-    m_fileCache.update();
-}
-
-/*!
-    Takes operations from the queue and executes them, until the queue is empty.
-    This must be run within the internal thread whenever an operation is added to the queue.
-    Canceled operations are not executed, but removed from the queue.
-    Before each operation, the cache of modified files is updated on the main thread.
-
-    \internal
-*/
-void AsyncGhcMod::reduceQueue()
-{
-    QTC_ASSERT(QThread::currentThread() != thread(), return);
-    const auto takeFirst = [this]() {
-        Operation op;
-        m_mutex.lock();
-        if (!m_queue.isEmpty())
-            op = m_queue.takeFirst();
-        m_mutex.unlock();
-        return op;
-    };
-
-    Operation op;
-    while ((op = takeFirst()).op) {
-        if (!op.fi.isCanceled()) {
-            QMetaObject::invokeMethod(this, "updateCache", Qt::BlockingQueuedConnection);
-            m_ghcmod.setFileMap(m_fileCache.fileMap());
-            QByteArrayOrError result = op.op();
-            op.fi.reportResult(result);
-        }
-        op.fi.reportFinished();
-    }
-}
-
-AsyncGhcMod::Operation::Operation(const std::function<QByteArrayOrError()> &op)
-    : op(op)
-{
-    fi.reportStarted();
-}
-
-} // Internal
-} // Haskell
diff --git a/plugins/haskell/ghcmod.h b/plugins/haskell/ghcmod.h
deleted file mode 100644
index fb3dd3f..0000000
--- a/plugins/haskell/ghcmod.h
+++ /dev/null
@@ -1,150 +0,0 @@
-/****************************************************************************
-**
-** 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 "filecache.h"
-
-#include <utils/fileutils.h>
-#include <utils/optional.h>
-#include <utils/synchronousprocess.h>
-#include <utils/variant.h>
-
-#include <QFuture>
-#include <QMutex>
-#include <QThread>
-
-#include <memory>
-
-QT_BEGIN_NAMESPACE
-class QProcess;
-QT_END_NAMESPACE
-
-namespace Haskell {
-namespace Internal {
-
-class Error {
-public:
-    enum class Type {
-        FailedToStartStack,
-        Other // TODO get rid of it
-    };
-    Type type;
-    QString details;
-};
-
-class SymbolInfo {
-public:
-    QStringList definition;
-    QStringList additionalInfo;
-    Utils::FilePath file;
-    int line = -1;
-    int col = -1;
-    QString module;
-};
-
-using QByteArrayOrError = Utils::variant<QByteArray, Error>;
-using QStringOrError = Utils::variant<QString, Error>;
-using SymbolInfoOrError = Utils::variant<SymbolInfo, Error>;
-
-template <typename T> class ghcmod_deleter;
-template <> class ghcmod_deleter<QProcess>
-{
-public:
-    void operator()(QProcess *p) { Utils::SynchronousProcess::stopProcess(*p); delete p; }
-};
-using unique_ghcmod_process = std::unique_ptr<QProcess, ghcmod_deleter<QProcess>>;
-
-class GhcMod
-{
-public:
-    GhcMod(const Utils::FilePath &path);
-    ~GhcMod();
-
-    Utils::FilePath basePath() const;
-    void setFileMap(const QHash<Utils::FilePath, Utils::FilePath> &fileMap);
-
-    SymbolInfoOrError findSymbol(const Utils::FilePath &filePath, const QString &symbol);
-    QStringOrError typeInfo(const Utils::FilePath &filePath, int line, int col);
-
-    QByteArrayOrError runQuery(const QString &query);
-
-    QByteArrayOrError runFindSymbol(const Utils::FilePath &filePath, const QString &symbol);
-    QByteArrayOrError runTypeInfo(const Utils::FilePath &filePath, int line, int col);
-
-    static SymbolInfoOrError parseFindSymbol(const QByteArrayOrError &response);
-    static QStringOrError parseTypeInfo(const QByteArrayOrError &response);
-
-   static void setStackExecutable(const Utils::FilePath &filePath);
-
-private:
-    Utils::optional<Error> ensureStarted();
-    void shutdown();
-    void log(const QString &message);
-
-    static Utils::FilePath m_stackExecutable;
-    static QMutex m_mutex;
-
-    Utils::FilePath m_path;
-    unique_ghcmod_process m_process; // kills process on reset
-    QHash<Utils::FilePath, Utils::FilePath> m_fileMap;
-};
-
-class AsyncGhcMod : public QObject
-{
-    Q_OBJECT
-
-public:
-    struct Operation {
-        Operation() = default;
-        Operation(const std::function<QByteArrayOrError()> &op);
-        mutable QFutureInterface<QByteArrayOrError> fi;
-        std::function<QByteArrayOrError()> op;
-    };
-
-    AsyncGhcMod(const Utils::FilePath &path);
-    ~AsyncGhcMod();
-
-    Utils::FilePath basePath() const;
-
-    QFuture<SymbolInfoOrError> findSymbol(const Utils::FilePath &filePath, const QString &symbol);
-    QFuture<QStringOrError> typeInfo(const Utils::FilePath &filePath, int line, int col);
-
-private slots:
-    void updateCache(); // called through QMetaObject::invokeMethod
-
-private:
-    void reduceQueue();
-
-    QThread m_thread;
-    QObject m_threadTarget; // used to run methods in m_thread
-    GhcMod m_ghcmod; // only use in m_thread
-    FileCache m_fileCache; // only update through reduceQueue
-    QVector<Operation> m_queue;
-    QMutex m_mutex;
-};
-
-} // Internal
-} // Haskell
diff --git a/plugins/haskell/haskell.pro b/plugins/haskell/haskell.pro
index 92d0307..df46a27 100644
--- a/plugins/haskell/haskell.pro
+++ b/plugins/haskell/haskell.pro
@@ -3,19 +3,12 @@ DEFINES += HASKELL_LIBRARY
 # Haskell files
 
 SOURCES += \
-    haskellcompletionassist.cpp \
     haskelleditorfactory.cpp \
-    haskellhoverhandler.cpp \
     haskellplugin.cpp \
     haskellhighlighter.cpp \
     haskelltokenizer.cpp \
-    ghcmod.cpp \
     haskellmanager.cpp \
-    haskelldocument.cpp \
     optionspage.cpp \
-    filecache.cpp \
-    haskelleditorwidget.cpp \
-    followsymbol.cpp \
     haskellproject.cpp \
     haskellbuildconfiguration.cpp \
     stackbuildstep.cpp \
@@ -23,20 +16,13 @@ SOURCES += \
 
 HEADERS += \
     haskell_global.h \
-    haskellcompletionassist.h \
     haskellconstants.h \
     haskelleditorfactory.h \
-    haskellhoverhandler.h \
     haskellplugin.h \
     haskellhighlighter.h \
     haskelltokenizer.h \
-    ghcmod.h \
     haskellmanager.h \
-    haskelldocument.h \
     optionspage.h \
-    filecache.h \
-    haskelleditorwidget.h \
-    followsymbol.h \
     haskellproject.h \
     haskellbuildconfiguration.h \
     stackbuildstep.h \
diff --git a/plugins/haskell/haskell.qbs b/plugins/haskell/haskell.qbs
index d2296a9..30eb832 100644
--- a/plugins/haskell/haskell.qbs
+++ b/plugins/haskell/haskell.qbs
@@ -11,19 +11,12 @@ QtcPlugin {
     Depends { name: "ProjectExplorer" }
 
     files: [
-        "filecache.cpp", "filecache.h",
-        "followsymbol.cpp", "followsymbol.h",
-        "ghcmod.cpp", "ghcmod.h",
         "haskell.qrc",
         "haskellbuildconfiguration.cpp", "haskellbuildconfiguration.h",
-        "haskellcompletionassist.cpp", "haskellcompletionassist.h",
         "haskellconstants.h",
-        "haskelldocument.cpp", "haskelldocument.h",
         "haskelleditorfactory.cpp", "haskelleditorfactory.h",
-        "haskelleditorwidget.cpp", "haskelleditorwidget.h",
         "haskell_global.h",
         "haskellhighlighter.cpp", "haskellhighlighter.h",
-        "haskellhoverhandler.cpp", "haskellhoverhandler.h",
         "haskellmanager.cpp", "haskellmanager.h",
         "haskellplugin.cpp", "haskellplugin.h",
         "haskellproject.cpp", "haskellproject.h",
diff --git a/plugins/haskell/haskellcompletionassist.cpp b/plugins/haskell/haskellcompletionassist.cpp
deleted file mode 100644
index aa053f5..0000000
--- a/plugins/haskell/haskellcompletionassist.cpp
+++ /dev/null
@@ -1,44 +0,0 @@
-/****************************************************************************
-**
-** 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 "haskellcompletionassist.h"
-
-#include "haskellconstants.h"
-
-#include <coreplugin/id.h>
-#include <texteditor/codeassist/keywordscompletionassist.h>
-
-namespace Haskell {
-namespace Internal {
-
-TextEditor::IAssistProcessor *HaskellCompletionAssistProvider::createProcessor() const
-{
-    auto processor = new TextEditor::KeywordsCompletionAssistProcessor(TextEditor::Keywords());
-    processor->setSnippetGroup(Constants::C_HASKELLSNIPPETSGROUP_ID);
-    return processor;
-}
-
-} // namespace Internal
-} // namespace Haskell
diff --git a/plugins/haskell/haskellcompletionassist.h b/plugins/haskell/haskellcompletionassist.h
deleted file mode 100644
index 9b3f0ca..0000000
--- a/plugins/haskell/haskellcompletionassist.h
+++ /dev/null
@@ -1,45 +0,0 @@
-/****************************************************************************
-**
-** 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.
-**
-****************************************************************************/
-
-#ifndef HASKELLCOMPLETIONASSIST_H
-#define HASKELLCOMPLETIONASSIST_H
-
-#include <texteditor/codeassist/completionassistprovider.h>
-
-namespace Haskell {
-namespace Internal {
-
-class HaskellCompletionAssistProvider : public TextEditor::CompletionAssistProvider
-{
-    Q_OBJECT
-
-public:
-    TextEditor::IAssistProcessor *createProcessor() const override;
-};
-
-} // namespace Internal
-} // namespace Haskell
-
-#endif // HASKELLCOMPLETIONASSIST_H
diff --git a/plugins/haskell/haskelldocument.cpp b/plugins/haskell/haskelldocument.cpp
deleted file mode 100644
index b2cc8e0..0000000
--- a/plugins/haskell/haskelldocument.cpp
+++ /dev/null
@@ -1,51 +0,0 @@
-/****************************************************************************
-**
-** 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 "haskelldocument.h"
-
-#include "haskellconstants.h"
-#include "haskellmanager.h"
-
-using namespace TextEditor;
-using namespace Utils;
-
-namespace Haskell {
-namespace Internal {
-
-HaskellDocument::HaskellDocument()
-    : TextDocument(Constants::C_HASKELLEDITOR_ID)
-{
-    connect(this, &IDocument::filePathChanged, this, [this](const FilePath &, const FilePath &fn) {
-        m_ghcmod = HaskellManager::ghcModForFile(fn);
-    });
-}
-
-std::shared_ptr<AsyncGhcMod> HaskellDocument::ghcMod() const
-{
-    return m_ghcmod;
-}
-
-} // namespace Internal
-} // namespace Haskell
diff --git a/plugins/haskell/haskelldocument.h b/plugins/haskell/haskelldocument.h
deleted file mode 100644
index 72af5e9..0000000
--- a/plugins/haskell/haskelldocument.h
+++ /dev/null
@@ -1,51 +0,0 @@
-/****************************************************************************
-**
-** 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 <texteditor/textdocument.h>
-
-#include <memory>
-
-namespace Haskell {
-namespace Internal {
-
-class AsyncGhcMod;
-
-class HaskellDocument : public TextEditor::TextDocument
-{
-    Q_OBJECT
-
-public:
-    HaskellDocument();
-
-    std::shared_ptr<AsyncGhcMod> ghcMod() const;
-
-private:
-    std::shared_ptr<AsyncGhcMod> m_ghcmod;
-};
-
-} // namespace Internal
-} // namespace Haskell
diff --git a/plugins/haskell/haskelleditorfactory.cpp b/plugins/haskell/haskelleditorfactory.cpp
index 8e5d837..6570d22 100644
--- a/plugins/haskell/haskelleditorfactory.cpp
+++ b/plugins/haskell/haskelleditorfactory.cpp
@@ -25,12 +25,8 @@
 
 #include "haskelleditorfactory.h"
 
-#include "haskellcompletionassist.h"
 #include "haskellconstants.h"
-#include "haskelldocument.h"
-#include "haskelleditorwidget.h"
 #include "haskellhighlighter.h"
-#include "haskellhoverhandler.h"
 
 #include <texteditor/textdocument.h>
 #include <texteditor/texteditoractionhandler.h>
@@ -47,13 +43,10 @@ HaskellEditorFactory::HaskellEditorFactory()
     addMimeType("text/x-haskell");
     setEditorActionHandlers(TextEditor::TextEditorActionHandler::UnCommentSelection
                             | TextEditor::TextEditorActionHandler::FollowSymbolUnderCursor);
-    addHoverHandler(new HaskellHoverHandler);
-    setDocumentCreator([] { return new HaskellDocument(); });
-    setEditorWidgetCreator([] { return new HaskellEditorWidget; });
+    setDocumentCreator([] { return new TextEditor::TextDocument(Constants::C_HASKELLEDITOR_ID); });
     setCommentDefinition(Utils::CommentDefinition("--", "{-", "-}"));
     setParenthesesMatchingEnabled(true);
     setMarksVisible(true);
-    setCompletionAssistProvider(new HaskellCompletionAssistProvider);
     setSyntaxHighlighterCreator([] { return new HaskellHighlighter(); });
 }
 
diff --git a/plugins/haskell/haskelleditorwidget.cpp b/plugins/haskell/haskelleditorwidget.cpp
deleted file mode 100644
index d4154ae..0000000
--- a/plugins/haskell/haskelleditorwidget.cpp
+++ /dev/null
@@ -1,113 +0,0 @@
-/****************************************************************************
-**
-** 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 "haskelleditorwidget.h"
-
-#include "haskellconstants.h"
-#include "haskelltokenizer.h"
-
-#include <coreplugin/icore.h>
-#include <coreplugin/infobar.h>
-#include <texteditor/textdocument.h>
-#include <utils/textutils.h>
-
-#include <QTextBlock>
-#include <QTimer>
-
-using namespace TextEditor;
-
-namespace Haskell {
-namespace Internal {
-
-HaskellEditorWidget::HaskellEditorWidget(QWidget *parent)
-    : TextEditorWidget(parent)
-{
-}
-
-Utils::optional<Token> HaskellEditorWidget::symbolAt(QTextDocument *doc, int position,
-                                                     int *line, int *column)
-{
-    Utils::Text::convertPosition(doc, position, line, column);
-    if (*line < 0 || *column < 0)
-        return Utils::nullopt;
-    const QTextBlock block = doc->findBlockByNumber(*line - 1);
-    if (block.text().isEmpty())
-        return Utils::nullopt;
-    const int startState = block.previous().isValid() ? block.previous().userState() : -1;
-    const Tokens tokens = HaskellTokenizer::tokenize(block.text(), startState);
-    const Token token = tokens.tokenAtColumn(*column);
-    if (token.isValid()
-            && (token.type == TokenType::Variable
-                || token.type == TokenType::Operator
-                || token.type == TokenType::Constructor
-                || token.type == TokenType::OperatorConstructor)) {
-        return token;
-    }
-    return Utils::nullopt;
-}
-
-void HaskellEditorWidget::showFailedToStartStackError(const QString &stackExecutable,
-                                                      TextEditorWidget *widget)
-{
-    static const char id[] = "Haskell.FailedToStartStack";
-    Core::IDocument *document = widget->textDocument();
-    if (!document->infoBar()->containsInfo(id)) {
-        Core::InfoBarEntry info(
-            id,
-            tr("Failed to start Haskell Stack \"%1\". Make sure you have stack installed and configured in the options.")
-                .arg(stackExecutable));
-        info.setCustomButtonInfo(Core::ICore::msgShowOptionsDialog(), [document] {
-            QTimer::singleShot(0, Core::ICore::instance(), [document] {
-                document->infoBar()->removeInfo(id);
-                Core::ICore::showOptionsDialog(Constants::OPTIONS_GENERAL);
-            });
-        });
-        document->infoBar()->addInfo(info);
-    }
-}
-
-void HaskellEditorWidget::findLinkAt(const QTextCursor &cursor,
-                                     Utils::ProcessLinkCallback &&processLinkCallback,
-                                     bool resolveTarget,
-                                     bool inNextSplit)
-{
-    Utils::Link link;
-    int line, column;
-    const Utils::optional<Token> symbol = symbolAt(document(), cursor.position(), &line, &column);
-    if (symbol) {
-        const QTextBlock block = document()->findBlockByNumber(line - 1);
-        Utils::Link link;
-        link.linkTextStart = block.position() + symbol->startCol;
-        link.linkTextEnd = link.linkTextStart + symbol->length;
-        if (resolveTarget) {
-            m_followSymbolAssistProvider.setOpenInNextSplit(inNextSplit);
-            invokeAssist(FollowSymbol, &m_followSymbolAssistProvider);
-        }
-    }
-    processLinkCallback(link);
-}
-
-} // namespace Internal
-} // namespace Haskell
diff --git a/plugins/haskell/haskelleditorwidget.h b/plugins/haskell/haskelleditorwidget.h
deleted file mode 100644
index 24af561..0000000
--- a/plugins/haskell/haskelleditorwidget.h
+++ /dev/null
@@ -1,60 +0,0 @@
-/****************************************************************************
-**
-** 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 "followsymbol.h"
-
-#include <texteditor/texteditor.h>
-#include <utils/optional.h>
-
-namespace Haskell {
-namespace Internal {
-
-class Token;
-
-class HaskellEditorWidget : public TextEditor::TextEditorWidget
-{
-public:
-    HaskellEditorWidget(QWidget *parent = 0);
-
-    static Utils::optional<Token> symbolAt(QTextDocument *doc, int position,
-                                           int *line, int *column);
-
-    static void showFailedToStartStackError(const QString &stackExecutable,
-                                            TextEditor::TextEditorWidget *widget);
-
-protected:
-    void findLinkAt(const QTextCursor &cursor,
-                    Utils::ProcessLinkCallback &&processLinkCallback,
-                    bool resolveTarget = true,
-                    bool inNextSplit = false) override;
-
-private:
-    FollowSymbolAssistProvider m_followSymbolAssistProvider;
-};
-
-} // namespace Internal
-} // namespace Haskell
diff --git a/plugins/haskell/haskellhoverhandler.cpp b/plugins/haskell/haskellhoverhandler.cpp
deleted file mode 100644
index 1719297..0000000
--- a/plugins/haskell/haskellhoverhandler.cpp
+++ /dev/null
@@ -1,166 +0,0 @@
-/****************************************************************************
-**
-** 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 "haskellhoverhandler.h"
-
-#include "haskelldocument.h"
-#include "haskelleditorwidget.h"
-#include "haskellmanager.h"
-#include "haskelltokenizer.h"
-
-#include <texteditor/textdocument.h>
-#include <texteditor/texteditor.h>
-#include <utils/qtcassert.h>
-#include <utils/runextensions.h>
-#include <utils/synchronousprocess.h>
-#include <utils/tooltip/tooltip.h>
-
-using namespace Utils;
-
-static QString toCode(const QString &s)
-{
-    if (s.isEmpty())
-        return s;
-    return "<pre>" + s.toHtmlEscaped() + "</pre>";
-}
-
-namespace Haskell {
-namespace Internal {
-
-QString symbolToHtml(const SymbolInfo &info)
-{
-    if (info.definition.isEmpty())
-        return QString();
-    QString result = "<pre>" + info.definition.join("\n") + "</pre>";
-    if (!info.file.isEmpty()) {
-        result += "<div align=\"right\"><i>-- " + info.file.toString();
-        if (info.line >= 0) {
-            result += ":" + QString::number(info.line);
-            if (info.col >= 0)
-                result += ":" + QString::number(info.col);
-        }
-        result += "</i></div>";
-    } else if (!info.module.isEmpty()) {
-        result += "<div align=\"right\"><i>-- Module \"" + info.module + "\"</i></div>";
-    }
-    if (!info.additionalInfo.isEmpty())
-        result += "<pre>" + info.additionalInfo.join("\n") + "</pre>";
-    return result;
-}
-
-void HaskellHoverHandler::identifyMatch(TextEditor::TextEditorWidget *editorWidget,
-                                        int pos,
-                                        ReportPriority report)
-{
-    cancel();
-    m_name.clear();
-    m_filePath.clear();
-    const Utils::optional<Token> token = HaskellEditorWidget::symbolAt(editorWidget->document(),
-                                                                       pos, &m_line, &m_col);
-    if (token) {
-        m_filePath = editorWidget->textDocument()->filePath();
-        m_name = token->text.toString();
-        setPriority(Priority_Tooltip);
-    } else {
-        setPriority(-1);
-    }
-    report(priority());
-}
-
-static void showError(const QPointer<TextEditor::TextEditorWidget> &widget,
-                      const Error &typeError, const Error &infoError)
-{
-    if (typeError.type == Error::Type::FailedToStartStack
-            || infoError.type == Error::Type::FailedToStartStack) {
-        const QString stackExecutable = typeError.type == Error::Type::FailedToStartStack
-                                            ? typeError.details
-                                            : infoError.details;
-        HaskellEditorWidget::showFailedToStartStackError(stackExecutable, widget);
-    }
-}
-
-static void tryShowToolTip(const QPointer<TextEditor::TextEditorWidget> &widget, const QPoint &point,
-                           QFuture<QStringOrError> typeFuture,
-                           QFuture<SymbolInfoOrError> symbolFuture)
-{
-    if (Utils::ToolTip::isVisible() && widget
-            && symbolFuture.isResultReadyAt(0) && typeFuture.isResultReadyAt(0)) {
-        const QStringOrError typeOrError = typeFuture.result();
-        const SymbolInfoOrError infoOrError = symbolFuture.result();
-        if (const Error *typeError = Utils::get_if<Error>(&typeOrError))
-            if (const Error *infoError = Utils::get_if<Error>(&infoOrError))
-                showError(widget, *typeError, *infoError);
-        const QString *type = Utils::get_if<QString>(&typeOrError);
-        const SymbolInfo *info = Utils::get_if<SymbolInfo>(&infoOrError);
-        const QString typeString = !type || type->isEmpty()
-                ? QString()
-                : toCode(":: " + *type);
-        const QString infoString = info ? symbolToHtml(*info) : QString();
-        const QString tip = typeString + infoString;
-        Utils::ToolTip::show(point, tip, widget);
-    }
-}
-
-void HaskellHoverHandler::operateTooltip(TextEditor::TextEditorWidget *editorWidget,
-                                         const QPoint &point)
-{
-    cancel();
-    if (m_name.isEmpty()) {
-        Utils::ToolTip::hide();
-        return;
-    }
-    Utils::ToolTip::show(point, HaskellManager::trLookingUp(m_name), editorWidget);
-
-    QPointer<TextEditor::TextEditorWidget> widget = editorWidget;
-    std::shared_ptr<AsyncGhcMod> ghcmod;
-    auto doc = qobject_cast<HaskellDocument *>(editorWidget->textDocument());
-    QTC_ASSERT(doc, return);
-    ghcmod = doc->ghcMod();
-    m_typeFuture = ghcmod->typeInfo(m_filePath, m_line, m_col);
-    m_symbolFuture = ghcmod->findSymbol(m_filePath, m_name);
-    Utils::onResultReady(m_typeFuture,
-                         [typeFuture = m_typeFuture, symbolFuture = m_symbolFuture,
-                          ghcmod, widget, point] // hold shared ghcmod pointer
-                         (const QStringOrError &) {
-                             tryShowToolTip(widget, point, typeFuture, symbolFuture);
-                         });
-    Utils::onResultReady(m_symbolFuture,
-                         [typeFuture = m_typeFuture, symbolFuture = m_symbolFuture,
-                          ghcmod, widget, point] // hold shared ghcmod pointer
-                         (const SymbolInfoOrError &) {
-                             tryShowToolTip(widget, point, typeFuture, symbolFuture);
-                         });
-}
-
-void HaskellHoverHandler::cancel()
-{
-    if (m_symbolFuture.isRunning())
-        m_symbolFuture.cancel();
-    if (m_typeFuture.isRunning())
-        m_typeFuture.cancel();
-}
-
-} // namespace Internal
-} // namespace Haskell
diff --git a/plugins/haskell/haskellhoverhandler.h b/plugins/haskell/haskellhoverhandler.h
deleted file mode 100644
index a85da8e..0000000
--- a/plugins/haskell/haskellhoverhandler.h
+++ /dev/null
@@ -1,57 +0,0 @@
-/****************************************************************************
-**
-** 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 "ghcmod.h"
-
-#include <texteditor/basehoverhandler.h>
-#include <utils/fileutils.h>
-#include <utils/optional.h>
-
-namespace Haskell {
-namespace Internal {
-
-class HaskellHoverHandler : public TextEditor::BaseHoverHandler
-{
-private:
-    void identifyMatch(TextEditor::TextEditorWidget *editorWidget,
-                       int pos,
-                       ReportPriority report) override;
-    void operateTooltip(TextEditor::TextEditorWidget *editorWidget, const QPoint &point) override;
-
-    void cancel();
-
-    Utils::FilePath m_filePath;
-    int m_line = -1;
-    int m_col = -1;
-    QString m_name;
-
-    QFuture<SymbolInfoOrError> m_symbolFuture;
-    QFuture<QStringOrError> m_typeFuture;
-};
-
-} // namespace Internal
-} // namespace Haskell
diff --git a/plugins/haskell/haskellmanager.cpp b/plugins/haskell/haskellmanager.cpp
index a2eadc6..9e18b51 100644
--- a/plugins/haskell/haskellmanager.cpp
+++ b/plugins/haskell/haskellmanager.cpp
@@ -25,8 +25,6 @@
 
 #include "haskellmanager.h"
 
-#include "ghcmod.h"
-
 #include <utils/hostosinfo.h>
 
 #include <QCoreApplication>
@@ -46,7 +44,6 @@ namespace Internal {
 class HaskellManagerPrivate
 {
 public:
-    std::unordered_map<FilePath, std::weak_ptr<AsyncGhcMod>> ghcModCache;
     FilePath stackExecutable;
 };
 
@@ -74,21 +71,6 @@ FilePath HaskellManager::findProjectDirectory(const FilePath &filePath)
     return {};
 }
 
-std::shared_ptr<AsyncGhcMod> HaskellManager::ghcModForFile(const FilePath &filePath)
-{
-    const FilePath projectPath = findProjectDirectory(filePath);
-    const auto cacheEntry = m_d->ghcModCache.find(projectPath);
-    if (cacheEntry != m_d->ghcModCache.cend()) {
-        if (cacheEntry->second.expired())
-            m_d->ghcModCache.erase(cacheEntry);
-        else
-            return cacheEntry->second.lock();
-    }
-    auto ghcmod = std::make_shared<AsyncGhcMod>(projectPath);
-    m_d->ghcModCache.insert(std::make_pair(projectPath, ghcmod));
-    return ghcmod;
-}
-
 FilePath defaultStackExecutable()
 {
     // stack from brew or the installer script from https://docs.haskellstack.org
@@ -127,10 +109,5 @@ void HaskellManager::writeSettings(QSettings *settings)
         settings->setValue(kStackExecutableKey, m_d->stackExecutable.toString());
 }
 
-QString HaskellManager::trLookingUp(const QString &name)
-{
-    return QCoreApplication::translate("HaskellManager", "Looking up \"%1\"...").arg(name);
-}
-
 } // namespace Internal
 } // namespace Haskell
diff --git a/plugins/haskell/haskellmanager.h b/plugins/haskell/haskellmanager.h
index b4a2e35..63013c9 100644
--- a/plugins/haskell/haskellmanager.h
+++ b/plugins/haskell/haskellmanager.h
@@ -36,8 +36,6 @@ QT_END_NAMESPACE
 namespace Haskell {
 namespace Internal {
 
-class AsyncGhcMod;
-
 class HaskellManager : public QObject
 {
     Q_OBJECT
@@ -46,14 +44,11 @@ public:
     static HaskellManager *instance();
 
     static Utils::FilePath findProjectDirectory(const Utils::FilePath &filePath);
-    static std::shared_ptr<AsyncGhcMod> ghcModForFile(const Utils::FilePath &filePath);
     static Utils::FilePath stackExecutable();
     static void setStackExecutable(const Utils::FilePath &filePath);
     static void readSettings(QSettings *settings);
     static void writeSettings(QSettings *settings);
 
-    static QString trLookingUp(const QString &name);
-
 signals:
     void stackExecutableChanged(const Utils::FilePath &filePath);
 };
diff --git a/plugins/haskell/haskellplugin.cpp b/plugins/haskell/haskellplugin.cpp
index d92c4f8..0aa187f 100644
--- a/plugins/haskell/haskellplugin.cpp
+++ b/plugins/haskell/haskellplugin.cpp
@@ -25,7 +25,6 @@
 
 #include "haskellplugin.h"
 
-#include "ghcmod.h"
 #include "haskellbuildconfiguration.h"
 #include "haskellconstants.h"
 #include "haskelleditorfactory.h"
@@ -72,8 +71,6 @@ bool HaskellPlugin::initialize(const QStringList &arguments, QString *errorStrin
     connect(Core::ICore::instance(), &Core::ICore::saveSettingsRequested, this, [] {
         HaskellManager::writeSettings(Core::ICore::settings());
     });
-    connect(HaskellManager::instance(), &HaskellManager::stackExecutableChanged,
-            &GhcMod::setStackExecutable);
 
     HaskellManager::readSettings(Core::ICore::settings());
     return true;