TestCase::mouseDrag: set mouse move delay >= 1 ms

Infinite-speed drags do not work well with velocity-sensitive
components like Flickable.  As with change d04982dc on qtbase,
adding a short delay helps to stabilize tests.

To keep it flexible, we make QTest::defaultMouseDelay()
available via the qtest_events.defaultMouseDelay property.
So the delay can be increased by passing a larger delay
value to mouseDrag, or by changing the QTEST_MOUSEEVENT_DELAY
environment variable (as before).

Task-number: QTBUG-55382
Change-Id: I8f8088758a206be104a439ee0d1832eeca574e8c
Reviewed-by: Liang Qi <liang.qi@qt.io>
Reviewed-by: Jan Arve Sæther <jan-arve.saether@theqtcompany.com>

3 files changed, 16 insertions, 8 deletions

diff --git a/src/imports/testlib/TestCase.qml b/src/imports/testlib/TestCase.qml
index c736a1a93a..46a395308d 100644
--- a/src/imports/testlib/TestCase.qml
+++ b/src/imports/testlib/TestCase.qml
@@ -1047,6 +1047,7 @@ Item {
             modifiers = Qt.NoModifier
         if (delay == undefined)
             delay = -1
+        var moveDelay = Math.max(1, delay === -1 ? qtest_events.defaultMouseDelay : delay)
 
         // Divide dx and dy to have intermediate mouseMove while dragging
         // Fractions of dx/dy need be superior to the dragThreshold
@@ -1060,12 +1061,12 @@ Item {
 
         mousePress(item, x, y, button, modifiers, delay)
         //trigger dragging
-        mouseMove(item, x + util.dragThreshold + 1, y + util.dragThreshold + 1, delay, button)
+        mouseMove(item, x + util.dragThreshold + 1, y + util.dragThreshold + 1, moveDelay, button)
         if (ddx > 0 || ddy > 0) {
-            mouseMove(item, x + ddx, y + ddy, delay, button)
-            mouseMove(item, x + 2*ddx, y + 2*ddy, delay, button)
+            mouseMove(item, x + ddx, y + ddy, moveDelay, button)
+            mouseMove(item, x + 2*ddx, y + 2*ddy, moveDelay, button)
         }
-        mouseMove(item, x + dx, y + dy, delay, button)
+        mouseMove(item, x + dx, y + dy, moveDelay, button)
         mouseRelease(item, x + dx, y + dy, button, modifiers, delay)
     }
 
diff --git a/src/qmltest/quicktestevent.cpp b/src/qmltest/quicktestevent.cpp
index cfa80c4f19..e71b4f8f54 100644
--- a/src/qmltest/quicktestevent.cpp
+++ b/src/qmltest/quicktestevent.cpp
@@ -39,6 +39,10 @@
 
 QT_BEGIN_NAMESPACE
 
+namespace QTest {
+    extern int Q_TESTLIB_EXPORT defaultMouseDelay();
+}
+
 QuickTestEvent::QuickTestEvent(QObject *parent)
     : QObject(parent)
 {
@@ -48,6 +52,11 @@ QuickTestEvent::~QuickTestEvent()
 {
 }
 
+int QuickTestEvent::defaultMouseDelay() const
+{
+    return QTest::defaultMouseDelay();
+}
+
 bool QuickTestEvent::keyPress(int key, int modifiers, int delay)
 {
     QWindow *window = activeWindow();
@@ -105,10 +114,6 @@ bool QuickTestEvent::keyClickChar(const QString &character, int modifiers, int d
     return true;
 }
 
-namespace QTest {
-    extern int Q_TESTLIB_EXPORT defaultMouseDelay();
-};
-
 namespace QtQuickTest
 {
     enum MouseAction { MousePress, MouseRelease, MouseClick, MouseDoubleClick, MouseMove, MouseDoubleClickSequence };
diff --git a/src/qmltest/quicktestevent_p.h b/src/qmltest/quicktestevent_p.h
index 0cba644cba..0a08347db8 100644
--- a/src/qmltest/quicktestevent_p.h
+++ b/src/qmltest/quicktestevent_p.h
@@ -53,9 +53,11 @@ QT_BEGIN_NAMESPACE
 class Q_QUICK_TEST_EXPORT QuickTestEvent : public QObject
 {
     Q_OBJECT
+    Q_PROPERTY(int defaultMouseDelay READ defaultMouseDelay FINAL)
 public:
     QuickTestEvent(QObject *parent = 0);
     ~QuickTestEvent();
+    int defaultMouseDelay() const;
 
 public Q_SLOTS:
     bool keyPress(int key, int modifiers, int delay);