Eradicate Q_FOREACH loops [1/2]: trivial cases

In this patch, we port Q_FOREACH loops to C++11 ranged-for loops. All cases are
trivial in the sense that either the argument is already const or is trivially
marked as const, either by qAsConst(), or, in the case of rvalues, by storing
to a const auto temporary first.

In addition, all loop bodies are clear enough to confirm that the container we
iterate over is not changed under iteration. This does not exclude cases where
a loop is prematurely exited just after calling a modifier on the container, as
that is safe, if not especially elegant.

Change-Id: I87a63f07797437d421567d60e52305391a3c4f21
Reviewed-by: Johan Helsing <johan.helsing@qt.io>
 

15 files changed, 48 insertions, 32 deletions

diff --git a/src/compositor/compositor_api/qwaylandcompositor.cpp b/src/compositor/compositor_api/qwaylandcompositor.cpp
index 530cf8ed6..36c995c3d 100644
--- a/src/compositor/compositor_api/qwaylandcompositor.cpp
+++ b/src/compositor/compositor_api/qwaylandcompositor.cpp
@@ -200,8 +200,8 @@ void QWaylandCompositorPrivate::init()
     buffer_manager = new QtWayland::BufferManager(q);
 
     wl_display_init_shm(display);
-    QVector<wl_shm_format> formats = QWaylandSharedMemoryFormatHelper::supportedWaylandFormats();
-    foreach (wl_shm_format format, formats)
+    const QVector<wl_shm_format> formats = QWaylandSharedMemoryFormatHelper::supportedWaylandFormats();
+    for (wl_shm_format format : formats)
         wl_display_add_shm_format(display, format);
 
     if (!socket_name.isEmpty()) {
@@ -706,7 +706,7 @@ QList<QWaylandSurface *> QWaylandCompositor::surfacesForClient(QWaylandClient* c
 {
     Q_D(const QWaylandCompositor);
     QList<QWaylandSurface *> surfs;
-    foreach (QWaylandSurface *surface, d->all_surfaces) {
+    for (QWaylandSurface *surface : d->all_surfaces) {
         if (surface->client() == client)
             surfs.append(surface);
     }
@@ -728,7 +728,7 @@ QList<QWaylandSurface *> QWaylandCompositor::surfaces() const
 QWaylandOutput *QWaylandCompositor::outputFor(QWindow *window) const
 {
     Q_D(const QWaylandCompositor);
-    foreach (QWaylandOutput *output, d->outputs) {
+    for (QWaylandOutput *output : d->outputs) {
         if (output->window() == window)
             return output;
     }
diff --git a/src/compositor/compositor_api/qwaylandkeyboard.cpp b/src/compositor/compositor_api/qwaylandkeyboard.cpp
index 2302c0b6a..452be4363 100644
--- a/src/compositor/compositor_api/qwaylandkeyboard.cpp
+++ b/src/compositor/compositor_api/qwaylandkeyboard.cpp
@@ -256,7 +256,8 @@ void QWaylandKeyboardPrivate::maybeUpdateKeymap()
         return;
 
     createXKBKeymap();
-    foreach (Resource *res, resourceMap()) {
+    const auto resMap = resourceMap();
+    for (Resource *res : resMap) {
         send_keymap(res->handle, WL_KEYBOARD_KEYMAP_FORMAT_XKB_V1, keymap_fd, keymap_size);
     }
 
@@ -386,7 +387,8 @@ void QWaylandKeyboardPrivate::createXKBKeymap()
 
 void QWaylandKeyboardPrivate::sendRepeatInfo()
 {
-    Q_FOREACH (Resource *resource, resourceMap()) {
+    const auto resMap = resourceMap();
+    for (Resource *resource : resMap) {
         if (resource->version() >= WL_KEYBOARD_REPEAT_INFO_SINCE_VERSION)
             send_repeat_info(resource->handle, repeatRate, repeatDelay);
     }
diff --git a/src/compositor/compositor_api/qwaylandoutput.cpp b/src/compositor/compositor_api/qwaylandoutput.cpp
index 006edbe6a..7a02d4caa 100644
--- a/src/compositor/compositor_api/qwaylandoutput.cpp
+++ b/src/compositor/compositor_api/qwaylandoutput.cpp
@@ -831,7 +831,8 @@ void QWaylandOutput::setScaleFactor(int scale)
 
     d->scaleFactor = scale;
 
-    Q_FOREACH (QWaylandOutputPrivate::Resource *resource, d->resourceMap().values()) {
+    const auto resMap = d->resourceMap();
+    for (QWaylandOutputPrivate::Resource *resource : resMap) {
         if (resource->version() >= 2) {
             d->send_scale(resource->handle, scale);
             d->send_done(resource->handle);
diff --git a/src/compositor/compositor_api/qwaylandsurface.cpp b/src/compositor/compositor_api/qwaylandsurface.cpp
index c79787e6e..add4020da 100644
--- a/src/compositor/compositor_api/qwaylandsurface.cpp
+++ b/src/compositor/compositor_api/qwaylandsurface.cpp
@@ -136,9 +136,9 @@ QWaylandSurfacePrivate::~QWaylandSurfacePrivate()
 
     bufferRef = QWaylandBufferRef();
 
-    foreach (QtWayland::FrameCallback *c, pendingFrameCallbacks)
+    for (QtWayland::FrameCallback *c : qAsConst(pendingFrameCallbacks))
         c->destroy();
-    foreach (QtWayland::FrameCallback *c, frameCallbacks)
+    for (QtWayland::FrameCallback *c : qAsConst(frameCallbacks))
         c->destroy();
 }
 
@@ -151,7 +151,7 @@ void QWaylandSurfacePrivate::removeFrameCallback(QtWayland::FrameCallback *callb
 void QWaylandSurfacePrivate::notifyViewsAboutDestruction()
 {
     Q_Q(QWaylandSurface);
-    foreach (QWaylandView *view, views) {
+    for (QWaylandView *view : qAsConst(views)) {
         QWaylandViewPrivate::get(view)->markSurfaceAsDestroyed(q);
     }
     if (hasContent) {
@@ -673,7 +673,7 @@ QWaylandCompositor *QWaylandSurface::compositor() const
 void QWaylandSurface::frameStarted()
 {
     Q_D(QWaylandSurface);
-    foreach (QtWayland::FrameCallback *c, d->frameCallbacks)
+    for (QtWayland::FrameCallback *c : qAsConst(d->frameCallbacks))
         c->canSend = true;
 }
 
diff --git a/src/compositor/compositor_api/qwaylandview.cpp b/src/compositor/compositor_api/qwaylandview.cpp
index 1a6bf1a64..12889bdfa 100644
--- a/src/compositor/compositor_api/qwaylandview.cpp
+++ b/src/compositor/compositor_api/qwaylandview.cpp
@@ -246,7 +246,8 @@ bool QWaylandView::advance()
         return false;
 
     if (d->surface && d->surface->primaryView() == this) {
-        Q_FOREACH (QWaylandView *view, d->surface->views()) {
+        const auto views = d->surface->views();
+        for (QWaylandView *view : views) {
             if (view != this && view->allowDiscardFrontBuffer() && view->d_func()->currentBuffer == d->currentBuffer)
                 view->discardCurrentBuffer();
         }
diff --git a/src/compositor/extensions/qwaylandqtwindowmanager.cpp b/src/compositor/extensions/qwaylandqtwindowmanager.cpp
index 86678b2e6..c3cf3488b 100644
--- a/src/compositor/extensions/qwaylandqtwindowmanager.cpp
+++ b/src/compositor/extensions/qwaylandqtwindowmanager.cpp
@@ -109,7 +109,8 @@ void QWaylandQtWindowManager::setShowIsFullScreen(bool value)
         return;
 
     d->showIsFullScreen = value;
-    Q_FOREACH (QWaylandQtWindowManagerPrivate::Resource *resource, d->resourceMap().values()) {
+    const auto resMap = d->resourceMap();
+    for (QWaylandQtWindowManagerPrivate::Resource *resource : resMap) {
         d->send_hints(resource->handle, static_cast<int32_t>(d->showIsFullScreen));
     }
     Q_EMIT showIsFullScreenChanged();
diff --git a/src/compositor/extensions/qwaylandtextinput.cpp b/src/compositor/extensions/qwaylandtextinput.cpp
index f60a32a14..b46caa641 100644
--- a/src/compositor/extensions/qwaylandtextinput.cpp
+++ b/src/compositor/extensions/qwaylandtextinput.cpp
@@ -162,7 +162,7 @@ void QWaylandTextInputPrivate::sendInputMethodEvent(QInputMethodEvent *event)
     afterCommit.cursorPosition += event->commitString().length();
     afterCommit.anchorPosition = afterCommit.cursorPosition;
 
-    foreach (const QInputMethodEvent::Attribute &attribute, event->attributes()) {
+    for (const QInputMethodEvent::Attribute &attribute : event->attributes()) {
         if (attribute.type == QInputMethodEvent::Selection) {
             afterCommit.cursorPosition = attribute.start;
             afterCommit.anchorPosition = attribute.length;
@@ -174,7 +174,7 @@ void QWaylandTextInputPrivate::sendInputMethodEvent(QInputMethodEvent *event)
         }
     }
     send_commit_string(focusResource->handle, event->commitString());
-    foreach (const QInputMethodEvent::Attribute &attribute, event->attributes()) {
+    for (const QInputMethodEvent::Attribute &attribute : event->attributes()) {
         if (attribute.type == QInputMethodEvent::Cursor) {
             int index = QWaylandInputMethodEventBuilder::indexToWayland(event->preeditString(), attribute.start);
             send_preedit_cursor(focusResource->handle, index);
diff --git a/src/compositor/extensions/qwaylandwlshell.cpp b/src/compositor/extensions/qwaylandwlshell.cpp
index 9871a8a5a..8cd2c7310 100644
--- a/src/compositor/extensions/qwaylandwlshell.cpp
+++ b/src/compositor/extensions/qwaylandwlshell.cpp
@@ -332,7 +332,7 @@ QList<QWaylandWlShellSurface *> QWaylandWlShell::shellSurfacesForClient(QWayland
 {
     Q_D(const QWaylandWlShell);
     QList<QWaylandWlShellSurface *> surfsForClient;
-    Q_FOREACH (QWaylandWlShellSurface *shellSurface, d->m_shellSurfaces) {
+    for (QWaylandWlShellSurface *shellSurface : d->m_shellSurfaces) {
         if (shellSurface->surface() && shellSurface->surface()->client() == client)
             surfsForClient.append(shellSurface);
     }
@@ -343,7 +343,7 @@ QList<QWaylandWlShellSurface *> QWaylandWlShell::mappedPopups() const
 {
     Q_D(const QWaylandWlShell);
     QList<QWaylandWlShellSurface *> popupSurfaces;
-    Q_FOREACH (QWaylandWlShellSurface *shellSurface, d->m_shellSurfaces) {
+    for (QWaylandWlShellSurface *shellSurface : d->m_shellSurfaces) {
         if (shellSurface->windowType() == Qt::WindowType::Popup
                 && shellSurface->surface() && shellSurface->surface()->hasContent()) {
             popupSurfaces.append(shellSurface);
@@ -355,7 +355,7 @@ QList<QWaylandWlShellSurface *> QWaylandWlShell::mappedPopups() const
 QWaylandClient *QWaylandWlShell::popupClient() const
 {
     Q_D(const QWaylandWlShell);
-    Q_FOREACH (QWaylandWlShellSurface *shellSurface, d->m_shellSurfaces) {
+    for (QWaylandWlShellSurface *shellSurface : d->m_shellSurfaces) {
         if (shellSurface->windowType() == Qt::WindowType::Popup
                 && shellSurface->surface() && shellSurface->surface()->hasContent()) {
             return shellSurface->surface()->client();
@@ -366,7 +366,8 @@ QWaylandClient *QWaylandWlShell::popupClient() const
 
 void QWaylandWlShell::closeAllPopups()
 {
-    Q_FOREACH (QWaylandWlShellSurface* shellSurface, mappedPopups())
+    const auto mapped = mappedPopups();
+    for (QWaylandWlShellSurface *shellSurface : mapped)
         shellSurface->sendPopupDone();
 }
 
diff --git a/src/compositor/extensions/qwaylandwlshellintegration.cpp b/src/compositor/extensions/qwaylandwlshellintegration.cpp
index 99a2e7655..b732069c4 100644
--- a/src/compositor/extensions/qwaylandwlshellintegration.cpp
+++ b/src/compositor/extensions/qwaylandwlshellintegration.cpp
@@ -198,7 +198,8 @@ void WlShellIntegration::handleSetPopup(QWaylandSeat *seat, QWaylandSurface *par
 
     // Find the parent item on the same output
     QWaylandQuickShellSurfaceItem *parentItem = nullptr;
-    Q_FOREACH (QWaylandView *view, parent->views()) {
+    const auto views = parent->views();
+    for (QWaylandView *view : views) {
         if (view->output() == m_item->view()->output()) {
             QWaylandQuickShellSurfaceItem *item = qobject_cast<QWaylandQuickShellSurfaceItem*>(view->renderObject());
             if (item) {
diff --git a/src/compositor/extensions/qwaylandxdgshell.cpp b/src/compositor/extensions/qwaylandxdgshell.cpp
index f06fd7934..eece3f3d6 100644
--- a/src/compositor/extensions/qwaylandxdgshell.cpp
+++ b/src/compositor/extensions/qwaylandxdgshell.cpp
@@ -1279,7 +1279,9 @@ QWaylandXdgToplevel *QWaylandXdgToplevel::fromResource(wl_resource *resource)
 QList<int> QWaylandXdgToplevel::statesAsInts() const
 {
    QList<int> list;
-   Q_FOREACH (uint state, states()) {
+   const auto s = states();
+   list.reserve(s.size());
+   for (auto state : s) {
        list << static_cast<int>(state);
    }
    return list;
diff --git a/src/compositor/extensions/qwaylandxdgshellv5.cpp b/src/compositor/extensions/qwaylandxdgshellv5.cpp
index a85efbc5f..eebfab6d6 100644
--- a/src/compositor/extensions/qwaylandxdgshellv5.cpp
+++ b/src/compositor/extensions/qwaylandxdgshellv5.cpp
@@ -414,7 +414,7 @@ void QWaylandXdgSurfaceV5Private::xdg_surface_ack_configure(Resource *resource,
             break;
     }
 
-    QVector<uint> changedStates;
+    std::vector<uint> changedStates;
     std::set_symmetric_difference(
                 m_lastAckedConfigure.states.begin(), m_lastAckedConfigure.states.end(),
                 config.states.begin(), config.states.end(),
@@ -423,7 +423,7 @@ void QWaylandXdgSurfaceV5Private::xdg_surface_ack_configure(Resource *resource,
     m_lastAckedConfigure = config;
 
     if (!changedStates.empty()) {
-        Q_FOREACH (uint state, changedStates) {
+        for (uint state : changedStates) {
             switch (state) {
             case QWaylandXdgSurfaceV5::State::MaximizedState:
                 emit q->maximizedChanged();
@@ -580,7 +580,7 @@ void QWaylandXdgShellV5::initialize()
 QWaylandClient *QWaylandXdgShellV5::popupClient() const
 {
     Q_D(const QWaylandXdgShellV5);
-    Q_FOREACH (QWaylandXdgPopupV5 *popup, d->m_xdgPopups) {
+    for (QWaylandXdgPopupV5 *popup : d->m_xdgPopups) {
         if (popup->surface()->hasContent())
             return popup->surface()->client();
     }
@@ -987,7 +987,9 @@ void QWaylandXdgSurfaceV5::initialize()
 QList<int> QWaylandXdgSurfaceV5::statesAsInts() const
 {
    QList<int> list;
-   Q_FOREACH (uint state, states()) {
+   const auto s = states();
+   list.reserve(s.size());
+   for (auto state : s) {
        list << static_cast<int>(state);
    }
    return list;
@@ -1238,7 +1240,8 @@ uint QWaylandXdgSurfaceV5::sendConfigure(const QSize &size, const QVector<uint>
 uint QWaylandXdgSurfaceV5::sendConfigure(const QSize &size, const QVector<QWaylandXdgSurfaceV5::State> &states)
 {
     QVector<uint> asUints;
-    Q_FOREACH (QWaylandXdgSurfaceV5::State state, states) {
+    asUints.reserve(states.size());
+    for (QWaylandXdgSurfaceV5::State state : states) {
         asUints << state;
     }
     return sendConfigure(size, asUints);
diff --git a/src/compositor/extensions/qwaylandxdgshellv6.cpp b/src/compositor/extensions/qwaylandxdgshellv6.cpp
index d1ee45dab..96d6f5509 100644
--- a/src/compositor/extensions/qwaylandxdgshellv6.cpp
+++ b/src/compositor/extensions/qwaylandxdgshellv6.cpp
@@ -1214,7 +1214,9 @@ QWaylandSurfaceRole *QWaylandXdgToplevelV6::role()
 QList<int> QWaylandXdgToplevelV6::statesAsInts() const
 {
    QList<int> list;
-   Q_FOREACH (uint state, states()) {
+   const auto s = states();
+   list.reserve(s.size());
+   for (auto state : s) {
        list << static_cast<int>(state);
    }
    return list;
diff --git a/src/compositor/global/qwaylandcompositorextension.cpp b/src/compositor/global/qwaylandcompositorextension.cpp
index 912985399..36daebce7 100644
--- a/src/compositor/global/qwaylandcompositorextension.cpp
+++ b/src/compositor/global/qwaylandcompositorextension.cpp
@@ -146,7 +146,7 @@ QWaylandObject::QWaylandObject(QObjectPrivate &d, QObject *parent)
 
 QWaylandObject::~QWaylandObject()
 {
-    foreach (QWaylandCompositorExtension *extension, extension_vector)
+    for (QWaylandCompositorExtension *extension : qAsConst(extension_vector))
         QWaylandCompositorExtensionPrivate::get(extension)->extension_container = nullptr;
 }
 
diff --git a/src/compositor/wayland_wrapper/qwldatadevicemanager.cpp b/src/compositor/wayland_wrapper/qwldatadevicemanager.cpp
index e30bc84f8..624a24b06 100644
--- a/src/compositor/wayland_wrapper/qwldatadevicemanager.cpp
+++ b/src/compositor/wayland_wrapper/qwldatadevicemanager.cpp
@@ -186,12 +186,12 @@ struct wl_display *DataDeviceManager::display() const
 
 void DataDeviceManager::overrideSelection(const QMimeData &mimeData)
 {
-    QStringList formats = mimeData.formats();
+    const QStringList formats = mimeData.formats();
     if (formats.isEmpty())
         return;
 
     m_retainedData.clear();
-    foreach (const QString &format, formats)
+    for (const QString &format : formats)
         m_retainedData.setData(format, mimeData.data(format));
 
     QWaylandCompositorPrivate::get(m_compositor)->feedRetainedSelectionData(&m_retainedData);
@@ -217,7 +217,8 @@ bool DataDeviceManager::offerFromCompositorToClient(wl_resource *clientDataDevic
              wl_resource_create(client, &wl_data_offer_interface, -1, 0);
     wl_resource_set_implementation(selectionOffer, &compositor_offer_interface, this, nullptr);
     wl_data_device_send_data_offer(clientDataDeviceResource, selectionOffer);
-    foreach (const QString &format, m_retainedData.formats()) {
+    const auto formats = m_retainedData.formats();
+    for (const QString &format : formats) {
         QByteArray ba = format.toLatin1();
         wl_data_offer_send_offer(selectionOffer, ba.constData());
     }
diff --git a/src/compositor/wayland_wrapper/qwldataoffer.cpp b/src/compositor/wayland_wrapper/qwldataoffer.cpp
index 9fea664ac..ddc5545e3 100644
--- a/src/compositor/wayland_wrapper/qwldataoffer.cpp
+++ b/src/compositor/wayland_wrapper/qwldataoffer.cpp
@@ -55,7 +55,8 @@ DataOffer::DataOffer(DataSource *dataSource, QtWaylandServer::wl_data_device::Re
 {
     // FIXME: connect to dataSource and reset m_dataSource on destroy
     target->data_device_object->send_data_offer(target->handle, resource()->handle);
-    Q_FOREACH (const QString &mimeType, dataSource->mimeTypes()) {
+    const auto mimeTypes = dataSource->mimeTypes();
+    for (const QString &mimeType : mimeTypes) {
         send_offer(mimeType);
     }
 }