fix reseting WeakReference when moving a ref to another ref.

In ViewIteratorImpl::Reverse we std::move a reference, to a local
variable, however the reference was not reset correctly, which
caused a crash.

The issue is that a mpWeakConnection in WeakReference always
needs to be non-null as shown in reset(reference_type* pReference)
method. In the move constructor of WeakReference, we just std::move
the reference like:

mpWeakConnection = std::move(rWeakRef.mpWeakConnection);

This means rWeakRef.mpWeakConnection will be reset to null, which
is not what is expected, so what is missing is to instantiate
rWeakRef.mpWeakConnection by calling reset(nullptr) or using the
added reset() method.

This also adds a test for LOKit PDF search as this is the case
where the crash has been reproduced. It happens because of a
call to:

... std::move(maPosition.mxObject);

in the method ViewIteratorImpl::Reverse()

Change-Id: I43692554ba4f6231d00091269b7c902ab5cbc11f
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/95995
Tested-by: Jenkins
Reviewed-by: Tomaž Vajngerl <quikee@gmail.com>

2 files changed, 39 insertions, 0 deletions

diff --git a/sd/qa/unit/tiledrendering/LOKitSearchTest.cxx b/sd/qa/unit/tiledrendering/LOKitSearchTest.cxx
index 91b5ecbc8473..ac2695441575 100644
--- a/sd/qa/unit/tiledrendering/LOKitSearchTest.cxx
+++ b/sd/qa/unit/tiledrendering/LOKitSearchTest.cxx
@@ -57,6 +57,7 @@ public:
     void testDontSearchInMasterPages();
     void testSearchInPDFNonExisting();
     void testSearchInPDF();
+    void testSearchInPDFOnePDFObject();
     void testSearchInPDFInMultiplePages();
     void testSearchInPDFInMultiplePagesBackwards();
     void testSearchIn2MixedObjects();
@@ -71,6 +72,7 @@ public:
     CPPUNIT_TEST(testDontSearchInMasterPages);
     CPPUNIT_TEST(testSearchInPDFNonExisting);
     CPPUNIT_TEST(testSearchInPDF);
+    CPPUNIT_TEST(testSearchInPDFOnePDFObject);
     CPPUNIT_TEST(testSearchInPDFInMultiplePages);
     CPPUNIT_TEST(testSearchInPDFInMultiplePagesBackwards);
     CPPUNIT_TEST(testSearchIn2MixedObjects);
@@ -342,6 +344,43 @@ void LOKitSearchTest::testSearchInPDF()
 #endif
 }
 
+void LOKitSearchTest::testSearchInPDFOnePDFObject()
+{
+#if HAVE_FEATURE_PDFIUM
+    SdXImpressDocument* pXImpressDocument = createDoc("OnePDFObject.odg");
+    sd::ViewShell* pViewShell = pXImpressDocument->GetDocShell()->GetViewShell();
+    CPPUNIT_ASSERT(pViewShell);
+    mpCallbackRecorder->registerCallbacksFor(pViewShell->GetViewShellBase());
+
+    SdPage* pPage = pViewShell->GetActualPage();
+    CPPUNIT_ASSERT(pPage);
+
+    SdrObject* pObject = pPage->GetObj(0);
+    CPPUNIT_ASSERT(pObject);
+
+    SdrGrafObj* pGraphicObject = dynamic_cast<SdrGrafObj*>(pObject);
+    CPPUNIT_ASSERT(pGraphicObject);
+
+    Graphic aGraphic = pGraphicObject->GetGraphic();
+    auto const& pVectorGraphicData = aGraphic.getVectorGraphicData();
+    CPPUNIT_ASSERT(pVectorGraphicData);
+    CPPUNIT_ASSERT_EQUAL(VectorGraphicDataType::Pdf,
+                         pVectorGraphicData->getVectorGraphicDataType());
+
+    // Search down
+    lcl_search("ABC", false, false);
+
+    CPPUNIT_ASSERT_EQUAL(true, mpCallbackRecorder->m_bFound);
+    CPPUNIT_ASSERT_EQUAL(1, mpCallbackRecorder->m_nSearchResultCount);
+
+    // Search up
+    lcl_search("ABC", false, true); // This caused a crash
+
+    CPPUNIT_ASSERT_EQUAL(true, mpCallbackRecorder->m_bFound);
+    CPPUNIT_ASSERT_EQUAL(2, mpCallbackRecorder->m_nSearchResultCount);
+#endif
+}
+
 void LOKitSearchTest::testSearchInPDFInMultiplePages()
 {
 #if HAVE_FEATURE_PDFIUM
diff --git a/sd/qa/unit/tiledrendering/data/OnePDFObject.odg b/sd/qa/unit/tiledrendering/data/OnePDFObject.odg
new file mode 100644
index 000000000000..225741c7b50b
--- /dev/null
+++ b/sd/qa/unit/tiledrendering/data/OnePDFObject.odg