LSP: collect and execute quick fixes via shortcut

Fixes: QTCREATORBUG-21802
Change-Id: I611fac1c3fc5b094816441e36492ed57706c98b8
Reviewed-by: Eike Ziller <eike.ziller@qt.io>

src/plugins/languageclient/languageclientquickfix.cpp

@@ -0,0 +1,166 @@
+/****************************************************************************
+**
+** Copyright (C) 2018 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 "languageclientquickfix.h"
+
+#include "client.h"
+#include "languageclientutils.h"
+
+#include <texteditor/codeassist/assistinterface.h>
+#include <texteditor/codeassist/genericproposal.h>
+#include <texteditor/codeassist/iassistprocessor.h>
+#include <texteditor/quickfix.h>
+
+
+using namespace LanguageServerProtocol;
+using namespace TextEditor;
+
+namespace LanguageClient {
+
+class CodeActionQuickFixOperation : public QuickFixOperation
+{
+public:
+    CodeActionQuickFixOperation(const CodeAction &action, Client *client)
+        : m_action(action)
+        , m_client(client)
+    { setDescription(action.title()); }
+
+    void perform() override
+    {
+        if (Utils::optional<WorkspaceEdit> edit = m_action.edit()) {
+            applyWorkspaceEdit(*edit);
+        } else if (Utils::optional<Command> command = m_action.command()) {
+            if (m_client)
+                m_client->executeCommand(*command);
+        }
+    }
+
+private:
+    CodeAction m_action;
+    QPointer<Client> m_client;
+};
+
+class CommandQuickFixOperation : public QuickFixOperation
+{
+public:
+    CommandQuickFixOperation(const Command &command, Client *client)
+        : m_command(command)
+        , m_client(client)
+    { setDescription(command.title()); }
+    void perform() override
+    {
+        if (m_client)
+            m_client->executeCommand(m_command);
+    }
+
+private:
+    Command m_command;
+    QPointer<Client> m_client;
+};
+
+class LanguageClientQuickFixAssistProcessor : public IAssistProcessor
+{
+public:
+    explicit LanguageClientQuickFixAssistProcessor(Client *client) : m_client(client) {}
+    bool running() override { return m_running; }
+    IAssistProposal *perform(const AssistInterface *interface) override;
+
+private:
+    void handleCodeActionResponse(const CodeActionRequest::Response &response);
+
+    QSharedPointer<const AssistInterface> m_assistInterface;
+    Client *m_client = nullptr; // not owned
+    bool m_running = false;
+};
+
+IAssistProposal *LanguageClientQuickFixAssistProcessor::perform(const AssistInterface *interface)
+{
+    m_assistInterface = QSharedPointer<const AssistInterface>(interface);
+
+    CodeActionParams params;
+    params.setContext({});
+    QTextCursor cursor(interface->textDocument());
+    cursor.setPosition(interface->position());
+    if (cursor.atBlockEnd() || cursor.atBlockStart())
+        cursor.select(QTextCursor::LineUnderCursor);
+    else
+        cursor.select(QTextCursor::WordUnderCursor);
+    if (!cursor.hasSelection())
+        cursor.select(QTextCursor::LineUnderCursor);
+    Range range(cursor);
+    params.setRange(range);
+    auto uri = DocumentUri::fromFileName(Utils::FileName::fromString(interface->fileName()));
+    params.setTextDocument(uri);
+    CodeActionParams::CodeActionContext context;
+    context.setDiagnostics(m_client->diagnosticsAt(uri, range));
+    params.setContext(context);
+
+    CodeActionRequest request(params);
+    request.setResponseCallback([this](const CodeActionRequest::Response &response){
+        handleCodeActionResponse(response);
+    });
+
+    m_client->requestCodeActions(request);
+    m_running = true;
+    return nullptr;
+}
+
+void LanguageClientQuickFixAssistProcessor::handleCodeActionResponse(
+        const CodeActionRequest::Response &response)
+{
+    m_running = false;
+    if (const Utils::optional<CodeActionRequest::Response::Error> &error = response.error())
+        m_client->log(*error);
+    QuickFixOperations ops;
+    if (const Utils::optional<CodeActionResult> &_result = response.result()) {
+        const CodeActionResult &result = _result.value();
+        if (auto list = Utils::get_if<QList<Utils::variant<Command, CodeAction>>>(&result)) {
+            for (const Utils::variant<Command, CodeAction> &item : *list) {
+                if (auto action = Utils::get_if<CodeAction>(&item))
+                    ops << new CodeActionQuickFixOperation(*action, m_client);
+                else if (auto command = Utils::get_if<Command>(&item))
+                    ops << new CommandQuickFixOperation(*command, m_client);
+            }
+        }
+    }
+    setAsyncProposalAvailable(GenericProposal::createProposal(m_assistInterface.data(), ops));
+}
+
+LanguageClientQuickFixProvider::LanguageClientQuickFixProvider(Client *client) : m_client(client)
+{
+    QTC_CHECK(client);
+}
+
+IAssistProvider::RunType LanguageClientQuickFixProvider::runType() const
+{
+    return Asynchronous;
+}
+
+IAssistProcessor *LanguageClientQuickFixProvider::createProcessor() const
+{
+    return new LanguageClientQuickFixAssistProcessor(m_client);
+}
+
+} // namespace LanguageClient