3 files changed, 40 insertions, 7 deletions

diff --git a/src/libs/installer/metadata.cpp b/src/libs/installer/metadata.cpp
index 0469ed8b1..c9fa0a0f1 100644
--- a/src/libs/installer/metadata.cpp
+++ b/src/libs/installer/metadata.cpp
@@ -36,6 +36,7 @@
 #include <QDir>
 #include <QDomDocument>
 #include <QFile>
+#include <QByteArrayMatcher>
 
 namespace QInstaller {
 
@@ -254,4 +255,32 @@ QString Metadata::persistentRepositoryPath()
     return m_persistentRepositoryPath;
 }
 
+/*!
+    Checks whether the updates document of this metadata contains the repository
+    update element, which can include actions to \c add, \c remove, and \c replace
+    repositories.
+
+    \note This function does not check that the repository updates are actually
+    valid, only that the updates document contains the \c RepositoryUpdate element.
+*/
+bool Metadata::containsRepositoryUpdates() const
+{
+    QFile updateFile(path() + QLatin1String("/Updates.xml"));
+    if (!updateFile.open(QIODevice::ReadOnly)) {
+        qCWarning(QInstaller::lcInstallerInstallLog)
+            << "Cannot open" << updateFile.fileName()
+            << "for reading:" << updateFile.errorString();
+        return false;
+    }
+
+    static const auto matcher = qMakeStaticByteArrayMatcher("<RepositoryUpdate>");
+    while (!updateFile.atEnd()) {
+        const QByteArray line = updateFile.readLine().simplified();
+        if (matcher.indexIn(line) != -1)
+            return true;
+    }
+
+    return false;
+}
+
 } // namespace QInstaller
diff --git a/src/libs/installer/metadata.h b/src/libs/installer/metadata.h
index af7acf6b9..3063be829 100644
--- a/src/libs/installer/metadata.h
+++ b/src/libs/installer/metadata.h
@@ -61,6 +61,8 @@ public:
     void setPersistentRepositoryPath(const QUrl &url);
     QString persistentRepositoryPath();
 
+    bool containsRepositoryUpdates() const;
+
 private:
     Repository m_repository;
     QString m_persistentRepositoryPath;
diff --git a/src/libs/installer/metadatajob.cpp b/src/libs/installer/metadatajob.cpp
index 5a7aa66f4..33aabd268 100644
--- a/src/libs/installer/metadatajob.cpp
+++ b/src/libs/installer/metadatajob.cpp
@@ -862,13 +862,15 @@ MetadataJob::Status MetadataJob::refreshCacheItem(const FileTaskResult &result,
         cachedMetadata->setPersistentRepositoryPath(repository.url());
 
         // search for additional repositories that we might need to check
-        QDomDocument doc = cachedMetadata->updatesDocument();
-        const Status status = parseRepositoryUpdates(doc.documentElement(), result, cachedMetadata);
-        if (status == XmlDownloadRetry) {
-            // The repository update may have removed or replaced current repositories,
-            // clear repository information from cached items and refresh on next fetch run.
-            resetCacheRepositories();
-            return status;
+        if (cachedMetadata->containsRepositoryUpdates()) {
+            QDomDocument doc = cachedMetadata->updatesDocument();
+            const Status status = parseRepositoryUpdates(doc.documentElement(), result, cachedMetadata);
+            if (status == XmlDownloadRetry) {
+                // The repository update may have removed or replaced current repositories,
+                // clear repository information from cached items and refresh on next fetch run.
+                resetCacheRepositories();
+                return status;
+            }
         }
         *refreshed = true;
         return XmlDownloadSuccess;