Android: fix Android assets handler not listing dirs with only sub dirs

It looks like AAssetDir_getNextFileName is not enough.
Directories that contain only other directories (no files)
were not listed.

On the other hand, AAssetManager_openDir() will always return a
pointer to initialized object (even if the specified directory does not
exists), so we can't just leave only it here.

Using FolderIterator as a last resort. This approach should not be too
time consuming.

As part of this fix, add some unit tests to cover/ensure assets
listing/iterating works as expected.

Fixes: QTBUG-107627
Pick-to: 6.4 6.2 5.15
Change-Id: Id375fe8f99f4ca3f8cad4756f783ffafe5c074df
Reviewed-by: Assam Boudjelthia <assam.boudjelthia@qt.io>

1 files changed, 8 insertions, 1 deletions

diff --git a/src/plugins/platforms/android/qandroidassetsfileenginehandler.cpp b/src/plugins/platforms/android/qandroidassetsfileenginehandler.cpp
index 67b2506e68..c7785486b0 100644
--- a/src/plugins/platforms/android/qandroidassetsfileenginehandler.cpp
+++ b/src/plugins/platforms/android/qandroidassetsfileenginehandler.cpp
@@ -108,6 +108,8 @@ public:
     FolderIterator(const QString &path)
         : m_path(path)
     {
+        // Note that empty dirs in the assets dir before the build are not going to be
+        // included in the final apk, so no empty folders should expected to be listed.
         QJniObject files = QJniObject::callStaticObjectMethod(QtAndroid::applicationClass(),
                                                                             "listAssetContent",
                                                                             "(Landroid/content/res/AssetManager;Ljava/lang/String;)[Ljava/lang/String;",
@@ -350,8 +352,13 @@ public:
         } else {
             auto *assetDir = AAssetManager_openDir(m_assetManager, m_fileName.toUtf8());
             if (assetDir) {
-                if (AAssetDir_getNextFileName(assetDir))
+                if (AAssetDir_getNextFileName(assetDir)
+                        || (!FolderIterator::fromCache(m_fileName, false)->empty())) {
+                    // If AAssetDir_getNextFileName is not valid, it still can be a directory that
+                    // contains only other directories (no files). FolderIterator will not be called
+                    // on the directory containing files so it should not be too time consuming now.
                     m_assetInfo->type = AssetItem::Type::Folder;
+                }
                 AAssetDir_close(assetDir);
             }
         }