Tests: Un-crash image comparison tests

When (naively) running the tests with High-DPI scaling active, the
test would assert on mismatching image sizes caused by the scaling.
Add an error message parameter to
QQuickVisualTestUtil::compareImages() for use with QVERIFY2, return
false instead of asserting on format/size mismatches and adapt the
usages. Remove duplicate code in tst_qquickwindow.

Change-Id: I76564f4125798fa1e065a0202b686bc7f5ec5680
Reviewed-by: Mitch Curtis <mitch.curtis@qt.io>

1 files changed, 7 insertions, 3 deletions

diff --git a/tests/auto/quick/scenegraph/tst_scenegraph.cpp b/tests/auto/quick/scenegraph/tst_scenegraph.cpp
index 2479450287..063358c795 100644
--- a/tests/auto/quick/scenegraph/tst_scenegraph.cpp
+++ b/tests/auto/quick/scenegraph/tst_scenegraph.cpp
@@ -264,6 +264,7 @@ void tst_SceneGraph::manyWindows()
     const int COUNT = 4;
 
     QImage baseLine;
+    QString errorMessage;
     for (int i=0; i<COUNT; ++i) {
         views << createView(file, parent.data(), (i % 2) * 100, (i / 2) * 100, 100, 100);
     }
@@ -275,7 +276,8 @@ void tst_SceneGraph::manyWindows()
             baseLine = content;
             QVERIFY(containsSomethingOtherThanWhite(baseLine));
         } else {
-            QVERIFY(compareImages(content, baseLine));
+            QVERIFY2(compareImages(content, baseLine, &errorMessage),
+                     qPrintable(errorMessage));
         }
     }
 
@@ -284,7 +286,8 @@ void tst_SceneGraph::manyWindows()
     QQuickView *last = createView(file, parent.data(), 100, 100, 100, 100);
     QVERIFY(QTest::qWaitForWindowExposed(last));
     views << last;
-    QVERIFY(compareImages(baseLine, last->grabWindow()));
+    QVERIFY2(compareImages(baseLine, last->grabWindow(), &errorMessage),
+             qPrintable(errorMessage));
 
     // Wipe and recreate all
     qDeleteAll(views);
@@ -297,7 +300,8 @@ void tst_SceneGraph::manyWindows()
         QQuickView *view = views.at(i);
         QVERIFY(QTest::qWaitForWindowExposed(view));
         QImage content = view->grabWindow();
-        QVERIFY(compareImages(content, baseLine));
+        QVERIFY2(compareImages(content, baseLine, &errorMessage),
+                 qPrintable(errorMessage));
     }
 }