Add tests that verify backend availability in QtMultimedia

This test verifies that the expected media backends are available on all
platforms.

Task-number: QTBUG-122976
Pick-to: 6.7 6.6 6.5
Change-Id: Ie21cf933fedaedfb3c06f0980fb13d47729ed69c
Reviewed-by: Artem Dyomin <artem.dyomin@qt.io>
Reviewed-by: Jøger Hansegård <joger.hansegard@qt.io>

2 files changed, 18 insertions, 16 deletions

diff --git a/src/multimedia/platform/qplatformmediaintegration.cpp b/src/multimedia/platform/qplatformmediaintegration.cpp
index 1eb113b28..dfa248c56 100644
--- a/src/multimedia/platform/qplatformmediaintegration.cpp
+++ b/src/multimedia/platform/qplatformmediaintegration.cpp
@@ -40,21 +40,6 @@ Q_GLOBAL_STATIC_WITH_ARGS(QFactoryLoader, loader,
 
 static const auto FFmpegBackend = QStringLiteral("ffmpeg");
 
-static QStringList availableBackends()
-{
-    QStringList list;
-
-    if (QFactoryLoader *fl = loader()) {
-        const auto keyMap = fl->keyMap();
-        for (auto it = keyMap.constBegin(); it != keyMap.constEnd(); ++it)
-            if (!list.contains(it.value()))
-                list << it.value();
-    }
-
-    qCDebug(qLcMediaPlugin) << "Available backends" << list;
-    return list;
-}
-
 static QString defaultBackend(const QStringList &backends)
 {
 #ifdef QT_DEFAULT_MEDIA_BACKEND
@@ -84,7 +69,7 @@ struct InstanceHolder
         if (!QCoreApplication::instance())
             qCCritical(qLcMediaPlugin()) << "Qt Multimedia requires a QCoreApplication instance";
 
-        const auto backends = availableBackends();
+        const QStringList backends = QPlatformMediaIntegration::availableBackends();
         QString backend = QString::fromUtf8(qgetenv("QT_MEDIA_BACKEND"));
         if (backend.isEmpty() && !backends.isEmpty())
             backend = defaultBackend(backends);
@@ -202,6 +187,21 @@ QPlatformMediaDevices *QPlatformMediaIntegration::mediaDevices()
 
 // clang-format on
 
+QStringList QPlatformMediaIntegration::availableBackends()
+{
+    QStringList list;
+
+    if (QFactoryLoader *fl = loader()) {
+        const auto keyMap = fl->keyMap();
+        for (auto it = keyMap.constBegin(); it != keyMap.constEnd(); ++it)
+            if (!list.contains(it.value()))
+                list << it.value();
+    }
+
+    qCDebug(qLcMediaPlugin) << "Available backends" << list;
+    return list;
+}
+
 QPlatformMediaIntegration::QPlatformMediaIntegration() = default;
 
 QPlatformMediaIntegration::~QPlatformMediaIntegration() = default;
diff --git a/src/multimedia/platform/qplatformmediaintegration_p.h b/src/multimedia/platform/qplatformmediaintegration_p.h
index d47687586..9c3d79a79 100644
--- a/src/multimedia/platform/qplatformmediaintegration_p.h
+++ b/src/multimedia/platform/qplatformmediaintegration_p.h
@@ -93,6 +93,8 @@ public:
 
     QPlatformMediaDevices *mediaDevices();
 
+    static QStringList availableBackends();
+
 protected:
     virtual QPlatformMediaFormatInfo *createFormatInfo();