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 530cf8ed..36c995c3 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 2302c0b6..452be436 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 006edbe6..7a02d4ca 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 c79787e6..add4020d 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 1a6bf1a6..12889bdf 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 86678b2e..c3cf3488 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 f60a32a1..b46caa64 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 9871a8a5..8cd2c731 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 99a2e765..b732069c 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 f06fd793..eece3f3d 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 a85efbc5..eebfab6d 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 d1ee45da..96d6f550 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 91298539..36daebce 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 e30bc84f..624a24b0 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 9fea664a..ddc5545e 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);
     }
 }