TextEditor: add tests for the code assistant

Task-number: QTCREATORBUG-28989
Change-Id: Id76d5df589ab50c7deb96b8ad29d1f29bc368e59
Reviewed-by: Christian Stenger <christian.stenger@qt.io>

src/plugins/texteditor/codeassist/codeassist_test.cpp

@@ -0,0 +1,152 @@
+// Copyright (C) 2016 The Qt Company Ltd.
+// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GPL-3.0-only WITH Qt-GPL-exception-1.0
+
+#ifdef WITH_TESTS
+
+#include "codeassist_test.h"
+
+#include "../texteditor.h"
+
+#include "assistinterface.h"
+#include "assistproposaliteminterface.h"
+#include "asyncprocessor.h"
+#include "completionassistprovider.h"
+#include "genericproposal.h"
+#include "genericproposalwidget.h"
+
+#include <coreplugin/coreconstants.h>
+#include <coreplugin/editormanager/editormanager.h>
+#include <utils/temporarydirectory.h>
+
+#include <QtTest/QtTest>
+
+namespace TextEditor::Internal {
+
+class TestProposalItem : public AssistProposalItemInterface
+{
+public:
+    QString m_text = "test";
+    bool m_implicitlyApplies = false;
+    bool m_prematurelyApplies = false;
+    QIcon m_icon;
+    QString m_detail = "detail";
+    bool m_isSnippet = false;
+    bool m_isValid = true;
+
+    QString text() const override { return m_text; }
+    bool implicitlyApplies() const override { return m_implicitlyApplies; }
+    bool prematurelyApplies(const QChar &) const override { return m_prematurelyApplies; }
+    QIcon icon() const override { return m_icon; }
+    QString detail() const override { return m_detail; }
+    bool isSnippet() const override { return m_isSnippet; }
+    bool isValid() const override { return m_isValid; }
+    quint64 hash() const override { return 0; } // used to remove duplicates
+};
+
+class OpenEditorItem : public TestProposalItem
+{
+public:
+    void apply(TextDocumentManipulatorInterface &, int) const override
+    {
+        m_openedEditor = Core::EditorManager::openEditor(m_filePath,
+                                                         Core::Constants::K_DEFAULT_TEXT_EDITOR_ID);
+    }
+
+    mutable Core::IEditor *m_openedEditor = nullptr;
+    Utils::FilePath m_filePath;
+};
+
+class TestProposalWidget : public GenericProposalWidget
+{
+public:
+    void showProposal(const QString &prefix) override
+    {
+        GenericProposalModelPtr proposalModel = model();
+        if (proposalModel && proposalModel->size() == 1) {
+            emit proposalItemActivated(proposalModel->proposalItem(0));
+            deleteLater();
+            return;
+        }
+        GenericProposalWidget::showProposal(prefix);
+    }
+};
+
+class TestProposal : public GenericProposal
+{
+public:
+    TestProposal(int pos, const QList<AssistProposalItemInterface *> &items)
+        : GenericProposal(pos, items)
+    {}
+    IAssistProposalWidget *createWidget() const override { return new TestProposalWidget; }
+};
+
+class TestProcessor : public AsyncProcessor
+{
+public:
+    TestProcessor(const QList<AssistProposalItemInterface *> &items)
+        : m_items(items)
+    {}
+    IAssistProposal *performAsync() override
+    { return new TestProposal(interface()->position(), m_items); }
+    QList<AssistProposalItemInterface *> m_items;
+};
+
+class TestProvider : public CompletionAssistProvider
+{
+public:
+    IAssistProcessor *createProcessor(const AssistInterface *assistInterface) const override
+    {
+        Q_UNUSED(assistInterface);
+        return new TestProcessor(m_items);
+    }
+    QList<AssistProposalItemInterface *> m_items;
+};
+
+void CodeAssistTests::initTestCase()
+{
+    Core::IEditor *editor = Core::EditorManager::openEditorWithContents(
+        Core::Constants::K_DEFAULT_TEXT_EDITOR_ID);
+    QVERIFY(editor);
+    m_editor = qobject_cast<BaseTextEditor *>(editor);
+    QVERIFY(m_editor);
+    m_editorsToClose << m_editor;
+    m_testProvider = new TestProvider();
+}
+
+static Utils::FilePath createBigFile()
+{
+    constexpr int textChunkSize = 65536; // from utils/textfileformat.cpp
+
+    const Utils::FilePath result = Utils::TemporaryDirectory::masterDirectoryFilePath() / "BigFile";
+    QByteArray data;
+    data.reserve(textChunkSize);
+    while (data.size() < textChunkSize)
+        data.append("bigfile line\n");
+    result.writeFileContents(data);
+    return result;
+}
+
+void CodeAssistTests::testFollowSymbolBigFile()
+{
+    auto item = new OpenEditorItem;
+    item->m_filePath = createBigFile();
+    m_testProvider->m_items = {item};
+    auto editorWidget = m_editor->editorWidget();
+
+    editorWidget->invokeAssist(FollowSymbol, m_testProvider);
+    QSignalSpy spy(editorWidget, &TextEditorWidget::assistFinished);
+    QVERIFY(spy.wait(1000));
+    QVERIFY(item->m_openedEditor);
+    m_editorsToClose << item->m_openedEditor;
+}
+
+void CodeAssistTests::cleanupTestCase()
+{
+    m_testProvider->m_items.clear();
+    Core::EditorManager::closeEditors(m_editorsToClose);
+    QVERIFY(Core::EditorManager::currentEditor() == nullptr);
+}
+
+} // namespace TextEditor::Internal
+
+#endif // ifdef WITH_TESTS