FakeVim: Accept suggestion with Tab Key

* Changed signals to callbacks as only one receiver was ever added
* Added "tabPressedInInsertMode" callback to allow accepting
  a suggestion with the Tab Key

Fixes: QTCREATORBUG-28830
Change-Id: Ie70ba595b8802b6100fff495164d8e0471b1354c
Reviewed-by: hjk <hjk@qt.io>

3 files changed, 96 insertions, 81 deletions

diff --git a/src/plugins/fakevim/fakevimhandler.cpp b/src/plugins/fakevim/fakevimhandler.cpp
index 05ea400bbb..bd1e035f48 100644
--- a/src/plugins/fakevim/fakevimhandler.cpp
+++ b/src/plugins/fakevim/fakevimhandler.cpp
@@ -5459,16 +5459,18 @@ void FakeVimHandler::Private::handleInsertMode(const Input &input)
     } else if (input.isKey(Key_PageUp) || input.isControl('b')) {
         movePageUp();
     } else if (input.isKey(Key_Tab)) {
-        m_buffer->insertState.insertingSpaces = true;
-        if (s.expandTab.value()) {
-            const int ts = s.tabStop.value();
-            const int col = logicalCursorColumn();
-            QString str = QString(ts - col % ts, ' ');
-            insertText(str);
-        } else {
-            insertInInsertMode(input.raw());
+        if (q->tabPressedInInsertMode()) {
+            m_buffer->insertState.insertingSpaces = true;
+            if (s.expandTab.value()) {
+                const int ts = s.tabStop.value();
+                const int col = logicalCursorColumn();
+                QString str = QString(ts - col % ts, ' ');
+                insertText(str);
+            } else {
+                insertInInsertMode(input.raw());
+            }
+            m_buffer->insertState.insertingSpaces = false;
         }
-        m_buffer->insertState.insertingSpaces = false;
     } else if (input.isControl('d')) {
         // remove one level of indentation from the current line
         const int shift = s.shiftWidth.value();
diff --git a/src/plugins/fakevim/fakevimhandler.h b/src/plugins/fakevim/fakevimhandler.h
index 30ee5599ef..b19e257909 100644
--- a/src/plugins/fakevim/fakevimhandler.h
+++ b/src/plugins/fakevim/fakevimhandler.h
@@ -61,23 +61,30 @@ enum MessageLevel
     MessageShowCmd  // partial command
 };
 
-template <typename Type>
-class Signal
+template<typename>
+class Callback;
+
+template<typename R, typename... Params>
+class Callback<R(Params...)>
 {
 public:
-    using Callable = std::function<Type>;
-
-    void connect(const Callable &callable) { m_callables.push_back(callable); }
+    static constexpr auto IsVoidReturnType = std::is_same_v<R, void>;
+    using Function = std::function<R(Params...)>;
+    void set(const Function &callable) { m_callable = callable; }
 
-    template <typename ...Args>
-    void operator()(Args ...args) const
+    R operator()(Params... params)
     {
-        for (const Callable &callable : m_callables)
-            callable(args...);
-   }
+        if (!m_callable)
+            return R();
+
+        if constexpr (IsVoidReturnType)
+            m_callable(std::forward<Params>(params)...);
+        else
+            return m_callable(std::forward<Params>(params)...);
+    }
 
 private:
-    std::vector<Callable> m_callables;
+    Function m_callable;
 };
 
 class FakeVimHandler : public QObject
@@ -131,33 +138,35 @@ public:
 
     bool eventFilter(QObject *ob, QEvent *ev) override;
 
-    Signal<void(const QString &msg, int cursorPos, int anchorPos, int messageLevel)> commandBufferChanged;
-    Signal<void(const QString &msg)> statusDataChanged;
-    Signal<void(const QString &msg)> extraInformationChanged;
-    Signal<void(const QList<QTextEdit::ExtraSelection> &selection)> selectionChanged;
-    Signal<void(const QString &needle)>  highlightMatches;
-    Signal<void(bool *moved, bool *forward, QTextCursor *cursor)> moveToMatchingParenthesis;
-    Signal<void(bool *result, QChar c)> checkForElectricCharacter;
-    Signal<void(int beginLine, int endLine, QChar typedChar)> indentRegion;
-    Signal<void(const QString &needle, bool forward)> simpleCompletionRequested;
-    Signal<void(const QString &key, int count)> windowCommandRequested;
-    Signal<void(bool reverse)> findRequested;
-    Signal<void(bool reverse)> findNextRequested;
-    Signal<void(bool *handled, const ExCommand &cmd)> handleExCommandRequested;
-    Signal<void()> requestDisableBlockSelection;
-    Signal<void(const QTextCursor &cursor)> requestSetBlockSelection;
-    Signal<void(QTextCursor *cursor)> requestBlockSelection;
-    Signal<void(bool *on)> requestHasBlockSelection;
-    Signal<void(int depth)> foldToggle;
-    Signal<void(bool fold)> foldAll;
-    Signal<void(int depth, bool dofold)> fold;
-    Signal<void(int count, bool current)> foldGoTo;
-    Signal<void(QChar mark, bool backTickMode, const QString &fileName)> requestJumpToLocalMark;
-    Signal<void(QChar mark, bool backTickMode, const QString &fileName)> requestJumpToGlobalMark;
-    Signal<void()> completionRequested;
-    Signal<void()> tabPreviousRequested;
-    Signal<void()> tabNextRequested;
-    Signal<void(bool insertMode)> modeChanged;
+    Callback<void(const QString &msg, int cursorPos, int anchorPos, int messageLevel)>
+        commandBufferChanged;
+    Callback<void(const QString &msg)> statusDataChanged;
+    Callback<void(const QString &msg)> extraInformationChanged;
+    Callback<void(const QList<QTextEdit::ExtraSelection> &selection)> selectionChanged;
+    Callback<void(const QString &needle)> highlightMatches;
+    Callback<void(bool *moved, bool *forward, QTextCursor *cursor)> moveToMatchingParenthesis;
+    Callback<void(bool *result, QChar c)> checkForElectricCharacter;
+    Callback<void(int beginLine, int endLine, QChar typedChar)> indentRegion;
+    Callback<void(const QString &needle, bool forward)> simpleCompletionRequested;
+    Callback<void(const QString &key, int count)> windowCommandRequested;
+    Callback<void(bool reverse)> findRequested;
+    Callback<void(bool reverse)> findNextRequested;
+    Callback<void(bool *handled, const ExCommand &cmd)> handleExCommandRequested;
+    Callback<void()> requestDisableBlockSelection;
+    Callback<void(const QTextCursor &cursor)> requestSetBlockSelection;
+    Callback<void(QTextCursor *cursor)> requestBlockSelection;
+    Callback<void(bool *on)> requestHasBlockSelection;
+    Callback<void(int depth)> foldToggle;
+    Callback<void(bool fold)> foldAll;
+    Callback<void(int depth, bool dofold)> fold;
+    Callback<void(int count, bool current)> foldGoTo;
+    Callback<void(QChar mark, bool backTickMode, const QString &fileName)> requestJumpToLocalMark;
+    Callback<void(QChar mark, bool backTickMode, const QString &fileName)> requestJumpToGlobalMark;
+    Callback<void()> completionRequested;
+    Callback<void()> tabPreviousRequested;
+    Callback<void()> tabNextRequested;
+    Callback<void(bool insertMode)> modeChanged;
+    Callback<bool()> tabPressedInInsertMode;
 
 public:
     class Private;
diff --git a/src/plugins/fakevim/fakevimplugin.cpp b/src/plugins/fakevim/fakevimplugin.cpp
index e41d83be2c..d0c399ac31 100644
--- a/src/plugins/fakevim/fakevimplugin.cpp
+++ b/src/plugins/fakevim/fakevimplugin.cpp
@@ -1586,7 +1586,7 @@ void FakeVimPluginPrivate::editorOpened(IEditor *editor)
     new DeferredDeleter(widget, handler);
     m_editorToHandler[editor].handler = handler;
 
-    handler->extraInformationChanged.connect([this](const QString &text) {
+    handler->extraInformationChanged.set([this](const QString &text) {
         EditorManager::splitSideBySide();
         QString title = "stdout.txt";
         IEditor *iedit = EditorManager::openEditorWithContents(Id(), &title, text.toUtf8());
@@ -1596,17 +1596,27 @@ void FakeVimPluginPrivate::editorOpened(IEditor *editor)
         handler->handleCommand("0");
     });
 
-    handler->commandBufferChanged
-            .connect([this, handler](const QString &contents, int cursorPos, int anchorPos, int messageLevel) {
-        showCommandBuffer(handler, contents, cursorPos, anchorPos, messageLevel);
-    });
+    handler->commandBufferChanged.set(
+        [this, handler](const QString &contents, int cursorPos, int anchorPos, int messageLevel) {
+            showCommandBuffer(handler, contents, cursorPos, anchorPos, messageLevel);
+        });
 
-    handler->selectionChanged.connect([tew](const QList<QTextEdit::ExtraSelection> &selection) {
+    handler->selectionChanged.set([tew](const QList<QTextEdit::ExtraSelection> &selection) {
         if (tew)
             tew->setExtraSelections(TextEditorWidget::FakeVimSelection, selection);
     });
 
-    handler->modeChanged.connect([tew, this, editor](bool insertMode) {
+    handler->tabPressedInInsertMode.set([tew]() {
+        auto suggestion = tew->currentSuggestion();
+        if (suggestion) {
+            suggestion->apply();
+            return false;
+        }
+
+        return true;
+    });
+
+    handler->modeChanged.set([tew, this, editor](bool insertMode) {
         HandlerAndData &handlerAndData = m_editorToHandler[editor];
 
         // We don't want to show suggestions unless we are in insert mode.
@@ -1617,7 +1627,7 @@ void FakeVimPluginPrivate::editorOpened(IEditor *editor)
             tew->clearSuggestion();
     });
 
-    handler->highlightMatches.connect([](const QString &needle) {
+    handler->highlightMatches.set([](const QString &needle) {
         for (IEditor *editor : EditorManager::visibleEditors()) {
             QWidget *w = editor->widget();
             if (auto find = Aggregation::query<IFindSupport>(w))
@@ -1625,7 +1635,7 @@ void FakeVimPluginPrivate::editorOpened(IEditor *editor)
         }
     });
 
-    handler->moveToMatchingParenthesis.connect([](bool *moved, bool *forward, QTextCursor *cursor) {
+    handler->moveToMatchingParenthesis.set([](bool *moved, bool *forward, QTextCursor *cursor) {
         *moved = false;
 
         bool undoFakeEOL = false;
@@ -1658,7 +1668,7 @@ void FakeVimPluginPrivate::editorOpened(IEditor *editor)
         }
     });
 
-    handler->indentRegion.connect([tew](int beginBlock, int endBlock, QChar typedChar) {
+    handler->indentRegion.set([tew](int beginBlock, int endBlock, QChar typedChar) {
         if (!tew)
             return;
 
@@ -1691,17 +1701,17 @@ void FakeVimPluginPrivate::editorOpened(IEditor *editor)
         }
     });
 
-    handler->checkForElectricCharacter.connect([tew](bool *result, QChar c) {
+    handler->checkForElectricCharacter.set([tew](bool *result, QChar c) {
         if (tew)
             *result = tew->textDocument()->indenter()->isElectricCharacter(c);
     });
 
-    handler->requestDisableBlockSelection.connect([tew] {
+    handler->requestDisableBlockSelection.set([tew] {
         if (tew)
             tew->setTextCursor(tew->textCursor());
     });
 
-    handler->requestSetBlockSelection.connect([tew](const QTextCursor &cursor) {
+    handler->requestSetBlockSelection.set([tew](const QTextCursor &cursor) {
         if (tew) {
             const TabSettings &tabs = tew->textDocument()->tabSettings();
             MultiTextCursor mtc;
@@ -1725,7 +1735,7 @@ void FakeVimPluginPrivate::editorOpened(IEditor *editor)
         }
     });
 
-    handler->requestBlockSelection.connect([tew](QTextCursor *cursor) {
+    handler->requestBlockSelection.set([tew](QTextCursor *cursor) {
         if (tew && cursor) {
             MultiTextCursor mtc = tew->multiTextCursor();
             *cursor = mtc.cursors().first();
@@ -1733,16 +1743,16 @@ void FakeVimPluginPrivate::editorOpened(IEditor *editor)
         }
     });
 
-    handler->requestHasBlockSelection.connect([tew](bool *on) {
+    handler->requestHasBlockSelection.set([tew](bool *on) {
         if (tew && on)
             *on = tew->multiTextCursor().hasMultipleCursors();
     });
 
-    handler->simpleCompletionRequested.connect([this, handler](const QString &needle, bool forward) {
+    handler->simpleCompletionRequested.set([this, handler](const QString &needle, bool forward) {
         runData->wordProvider.setActive(needle, forward, handler);
     });
 
-    handler->windowCommandRequested.connect([this, handler](const QString &map, int count) {
+    handler->windowCommandRequested.set([this, handler](const QString &map, int count) {
         // normalize mapping
         const QString key = map.toUpper();
 
@@ -1772,22 +1782,22 @@ void FakeVimPluginPrivate::editorOpened(IEditor *editor)
             qDebug() << "UNKNOWN WINDOW COMMAND: <C-W>" << map;
     });
 
-    handler->findRequested.connect([](bool reverse) {
+    handler->findRequested.set([](bool reverse) {
         Find::setUseFakeVim(true);
         Find::openFindToolBar(reverse ? Find::FindBackwardDirection
                                       : Find::FindForwardDirection);
     });
 
-    handler->findNextRequested.connect([](bool reverse) {
+    handler->findNextRequested.set([](bool reverse) {
         triggerAction(reverse ? Core::Constants::FIND_PREVIOUS : Core::Constants::FIND_NEXT);
     });
 
-    handler->foldToggle.connect([this, handler](int depth) {
+    handler->foldToggle.set([this, handler](int depth) {
         QTextBlock block = handler->textCursor().block();
         fold(handler, depth, !TextDocumentLayout::isFolded(block));
     });
 
-    handler->foldAll.connect([handler](bool fold) {
+    handler->foldAll.set([handler](bool fold) {
         QTextDocument *document = handler->textCursor().document();
         auto documentLayout = qobject_cast<TextDocumentLayout*>(document->documentLayout());
         QTC_ASSERT(documentLayout, return);
@@ -1802,11 +1812,9 @@ void FakeVimPluginPrivate::editorOpened(IEditor *editor)
         documentLayout->emitDocumentSizeChanged();
     });
 
-    handler->fold.connect([this, handler](int depth, bool dofold) {
-        fold(handler, depth, dofold);
-    });
+    handler->fold.set([this, handler](int depth, bool dofold) { fold(handler, depth, dofold); });
 
-    handler->foldGoTo.connect([handler](int count, bool current) {
+    handler->foldGoTo.set([handler](int count, bool current) {
         QTextCursor tc = handler->textCursor();
         QTextBlock block = tc.block();
 
@@ -1858,7 +1866,7 @@ void FakeVimPluginPrivate::editorOpened(IEditor *editor)
         }
     });
 
-    handler->requestJumpToGlobalMark.connect(
+    handler->requestJumpToGlobalMark.set(
         [this](QChar mark, bool backTickMode, const QString &fileName) {
             if (IEditor *iedit = EditorManager::openEditor(FilePath::fromString(fileName))) {
                 if (FakeVimHandler *handler = m_editorToHandler.value(iedit, {}).handler)
@@ -1866,19 +1874,15 @@ void FakeVimPluginPrivate::editorOpened(IEditor *editor)
             }
         });
 
-    handler->handleExCommandRequested.connect([this, handler](bool *handled, const ExCommand &cmd) {
+    handler->handleExCommandRequested.set([this, handler](bool *handled, const ExCommand &cmd) {
         handleExCommand(handler, handled, cmd);
     });
 
-    handler->tabNextRequested.connect([] {
-        triggerAction(Core::Constants::GOTONEXTINHISTORY);
-    });
+    handler->tabNextRequested.set([] { triggerAction(Core::Constants::GOTONEXTINHISTORY); });
 
-    handler->tabPreviousRequested.connect([] {
-        triggerAction(Core::Constants::GOTOPREVINHISTORY);
-    });
+    handler->tabPreviousRequested.set([] { triggerAction(Core::Constants::GOTOPREVINHISTORY); });
 
-    handler->completionRequested.connect([this, tew] {
+    handler->completionRequested.set([this, tew] {
         if (tew)
             tew->invokeAssist(Completion, &runData->wordProvider);
     });