QtConcurrent: add fluent interface to configure a task before run

Task-number: QTBUG-82950
Change-Id: I449da938b6b501a7646b3425edde5c880d6ca87e
Reviewed-by: Qt CI Bot <[email protected]>
Reviewed-by: Paul Wicking <[email protected]>
Reviewed-by: Mikhail Svetkin <[email protected]>

1 files changed, 13 insertions, 4 deletions

diff --git a/src/concurrent/qtconcurrentrunbase.h b/src/concurrent/qtconcurrentrunbase.h
index aaa1245856b..e84c0cdb670 100644
--- a/src/concurrent/qtconcurrentrunbase.h
+++ b/src/concurrent/qtconcurrentrunbase.h
@@ -69,25 +69,34 @@ struct SelectSpecialization<void>
     struct Type { typedef Void type; };
 };
 
+struct TaskStartParameters
+{
+    QThreadPool *threadPool = QThreadPool::globalInstance();
+    int priority = 0;
+};
+
 template <typename T>
 class RunFunctionTaskBase : public QFutureInterface<T> , public QRunnable
 {
 public:
     QFuture<T> start()
     {
-        return start(QThreadPool::globalInstance());
+        return start(TaskStartParameters());
     }
 
-    QFuture<T> start(QThreadPool *pool)
+    QFuture<T> start(const TaskStartParameters &parameters)
     {
-        this->setThreadPool(pool);
+        this->setThreadPool(parameters.threadPool);
         this->setRunnable(this);
         this->reportStarted();
         QFuture<T> theFuture = this->future();
-        pool->start(this, /*m_priority*/ 0);
+        parameters.threadPool->start(this, parameters.priority);
         return theFuture;
     }
 
+    // For backward compatibility
+    QFuture<T> start(QThreadPool *pool) { return start({pool, 0});  }
+
     void run() override {}
     virtual void runFunctor() = 0;
 };