Fix QBuffer::updateData being called several times in a row

QBuffer::updateData would send a single update at the time and would
overwrite the latest update if it was called again before synching with
the backend took place.

This patches fixes by storing a list of pending updates instead.

Change-Id: I1fc501ad921c953ec88117fcc49c0cfcde6ca8aa
Task-number: QTBUG-81921
Reviewed-by: Mike Krus <mike.krus@kdab.com>

2 files changed, 81 insertions, 0 deletions

diff --git a/tests/auto/render/buffer/tst_buffer.cpp b/tests/auto/render/buffer/tst_buffer.cpp
index 5c2ae296d..2401c2789 100644
--- a/tests/auto/render/buffer/tst_buffer.cpp
+++ b/tests/auto/render/buffer/tst_buffer.cpp
@@ -365,6 +365,40 @@ private Q_SLOTS:
         // THEN
         QCOMPARE(renderer.dirtyBits(), Qt3DRender::Render::AbstractRenderer::BuffersDirty);
     }
+
+    void checkHandlesMultipleUpdates()
+    {
+        // GIVEN
+        Qt3DRender::Render::Buffer renderBuffer;
+        Qt3DRender::QBuffer buffer;
+        Qt3DRender::Render::BufferManager bufferManager;
+        TestRenderer renderer;
+
+        const QByteArray initData("000000");
+        buffer.setData(initData);
+
+        renderBuffer.setRenderer(&renderer);
+        renderBuffer.setManager(&bufferManager);
+
+        simulateInitializationSync(&buffer, &renderBuffer);
+
+        // THEN
+        QCOMPARE(renderBuffer.data(), initData);
+        renderBuffer.pendingBufferUpdates().clear();
+
+        // WHEN
+        buffer.updateData(0, QByteArray("012"));
+        buffer.updateData(3, QByteArray("345"));
+        renderBuffer.syncFromFrontEnd(&buffer, false);
+
+        // THEN
+        QCOMPARE(renderBuffer.pendingBufferUpdates().size(), 2);
+        QCOMPARE(renderBuffer.pendingBufferUpdates().first().offset, 0);
+        QCOMPARE(renderBuffer.pendingBufferUpdates().first().data, QByteArray("012"));
+        QCOMPARE(renderBuffer.pendingBufferUpdates().last().offset, 3);
+        QCOMPARE(renderBuffer.pendingBufferUpdates().last().data, QByteArray("345"));
+        QCOMPARE(renderBuffer.data(), QByteArray("012345"));
+    }
 };
 
 
diff --git a/tests/auto/render/qbuffer/tst_qbuffer.cpp b/tests/auto/render/qbuffer/tst_qbuffer.cpp
index fd96bf1c2..084ad0347 100644
--- a/tests/auto/render/qbuffer/tst_qbuffer.cpp
+++ b/tests/auto/render/qbuffer/tst_qbuffer.cpp
@@ -181,6 +181,53 @@ private Q_SLOTS:
         QCOMPARE(arbiter.dirtyNodes.size(), 1);
         QCOMPARE(arbiter.dirtyNodes.front(), buffer.data());
     }
+
+    void checkAccumulatesBufferUpdates()
+    {
+        // GIVEN
+        TestArbiter arbiter;
+        QScopedPointer<Qt3DRender::QBuffer> buffer(new Qt3DRender::QBuffer);
+        arbiter.setArbiterOnNode(buffer.data());
+
+        QByteArray initData(6, '\0');
+        buffer->setData(initData);
+
+        // THEN
+        QCOMPARE(buffer->data(), initData);
+        QCOMPARE(buffer->property(Qt3DRender::QBufferPrivate::UpdateDataPropertyName), QVariant());
+
+        // WHEN
+        const QByteArray uData("012");
+        buffer->updateData(0, uData);
+
+        // THEN
+        {
+            const QVariant v = buffer->property(Qt3DRender::QBufferPrivate::UpdateDataPropertyName);
+            QVERIFY(v.isValid());
+            const QVariantList l = v.toList();
+            QCOMPARE(l.size(), 1);
+            const Qt3DRender::QBufferUpdate update = l.first().value<Qt3DRender::QBufferUpdate>();
+            QCOMPARE(update.offset, 0);
+            QCOMPARE(update.data, uData);
+            QCOMPARE(buffer->data().mid(0, 3), uData);
+        }
+
+        // WHEN
+        const QByteArray uData2("345");
+        buffer->updateData(3, uData2);
+
+        // THEN
+        {
+            const QVariant v = buffer->property(Qt3DRender::QBufferPrivate::UpdateDataPropertyName);
+            QVERIFY(v.isValid());
+            const QVariantList l = v.toList();
+            QCOMPARE(l.size(), 2);
+            const Qt3DRender::QBufferUpdate update = l.last().value<Qt3DRender::QBufferUpdate>();
+            QCOMPARE(update.offset, 3);
+            QCOMPARE(update.data, uData2);
+            QCOMPARE(buffer->data(), QByteArray("012345"));
+        }
+    }
 };
 
 QTEST_MAIN(tst_QBuffer)