Optimize QPromise destructor

Unify cancel and finish in QPromise destructor in a single call. This
saves us one extra mutex lock and atomic state change.

Task-number: QTBUG-84977
Change-Id: Iac06302c39a2863008b27325fcf6792d4f58c8ae
Reviewed-by: Mårten Nordheim <marten.nordheim@qt.io>

1 files changed, 34 insertions, 0 deletions

diff --git a/tests/auto/corelib/thread/qfuture/tst_qfuture.cpp b/tests/auto/corelib/thread/qfuture/tst_qfuture.cpp
index 7703261832..a6be2e9727 100644
--- a/tests/auto/corelib/thread/qfuture/tst_qfuture.cpp
+++ b/tests/auto/corelib/thread/qfuture/tst_qfuture.cpp
@@ -107,6 +107,7 @@ private slots:
     void futureInterface();
     void refcounting();
     void cancel();
+    void cancelAndFinish();
     void statePropagation();
     void multipleResults();
     void indexedResults();
@@ -865,6 +866,39 @@ void tst_QFuture::cancel()
     }
 }
 
+void tst_QFuture::cancelAndFinish()
+{
+    {
+        QFutureInterface<void> fi;
+
+        fi.reportStarted();
+        fi.cancelAndFinish();
+
+        QVERIFY(fi.isStarted());
+        QVERIFY(!fi.isRunning());
+        QVERIFY(!fi.isSuspended());
+        QVERIFY(!fi.isSuspending());
+        QVERIFY(fi.isCanceled());
+        QVERIFY(fi.isFinished());
+    }
+
+    // The same with suspended state
+    {
+        QFutureInterface<void> fi;
+
+        fi.reportStarted();
+        fi.setSuspended(true);
+        fi.cancelAndFinish();
+
+        QVERIFY(fi.isStarted());
+        QVERIFY(!fi.isRunning());
+        QVERIFY(!fi.isSuspended());
+        QVERIFY(!fi.isSuspending());
+        QVERIFY(fi.isCanceled());
+        QVERIFY(fi.isFinished());
+    }
+}
+
 void tst_QFuture::statePropagation()
 {
     QFuture<void> f1;