QLibrary: fix load() after a failed load()

Regression introduced by commit 8d4eb292b2e8fc14437db97febdc2eebe36ed3ce
in 6.0, when QTaggedPointer was introduced. We set the tag even when the
loading failed and failed to reset it because d = {} retains the tag.

Pick-to: 6.2 6.4
Fixes: QTBUG-103387
Change-Id: Ie4bb662dcb274440ab8bfffd170a07aa9c9ecfca
Reviewed-by: Marc Mutz <marc.mutz@qt.io>

1 files changed, 74 insertions, 0 deletions

diff --git a/tests/auto/corelib/plugin/qlibrary/tst_qlibrary.cpp b/tests/auto/corelib/plugin/qlibrary/tst_qlibrary.cpp
index a64f7785b0..2a494cb12d 100644
--- a/tests/auto/corelib/plugin/qlibrary/tst_qlibrary.cpp
+++ b/tests/auto/corelib/plugin/qlibrary/tst_qlibrary.cpp
@@ -90,10 +90,14 @@ private slots:
     void unload_data();
     void unload();
     void unload_after_implicit_load();
+    void setFilenameAfterFailedLoad();
+    void loadAfterFailedLoad();
     void isLibrary_data();
     void isLibrary();
     void version_data();
     void version();
+    void setFileNameAndVersionAfterFailedLoad_data() { version_data(); }
+    void setFileNameAndVersionAfterFailedLoad();
     void errorString_data();
     void errorString();
     void loadHints();
@@ -272,6 +276,76 @@ void tst_QLibrary::unload_after_implicit_load()
     QCOMPARE(library.isLoaded(), false);
 }
 
+void tst_QLibrary::setFilenameAfterFailedLoad()
+{
+#if defined(Q_OS_WIN) || defined(Q_OS_ANDROID)
+    QSKIP("### FIXME: The helper libraries are currently messed up in the CMakeLists.txt");
+#endif
+
+    QLibrary library(directory + "/nolib");
+    QVERIFY(!library.load());
+    QVERIFY(!library.isLoaded());
+    QVERIFY(!library.load());
+    QVERIFY(!library.isLoaded());
+
+    library.setFileName(directory + "/mylib");
+    QVERIFY(library.load());
+    QVERIFY(library.isLoaded());
+    auto p = (VersionFunction)library.resolve("mylibversion");
+    QVERIFY(p);
+    QCOMPARE(p(), 2);
+    library.unload();
+}
+
+void tst_QLibrary::setFileNameAndVersionAfterFailedLoad()
+{
+    QLibrary library(directory + "/nolib");
+    QVERIFY(!library.load());
+    QVERIFY(!library.isLoaded());
+    QVERIFY(!library.load());
+    QVERIFY(!library.isLoaded());
+
+#if !defined(Q_OS_AIX) && !defined(Q_OS_WIN)
+    QFETCH(QString, lib);
+    QFETCH(int, loadversion);
+    QFETCH(int, resultversion);
+
+    library.setFileNameAndVersion(directory + '/' + lib, loadversion);
+    QVERIFY(library.load());
+    QVERIFY(library.isLoaded());
+    auto p = (VersionFunction)library.resolve("mylibversion");
+    QVERIFY(p);
+    QCOMPARE(p(), resultversion);
+    library.unload();
+#endif
+}
+
+void tst_QLibrary::loadAfterFailedLoad()
+{
+#if defined(Q_OS_WIN) || defined(Q_OS_ANDROID)
+    QSKIP("### FIXME: The helper libraries are currently messed up in the CMakeLists.txt");
+#endif
+
+    QTemporaryDir dir;
+    QLibrary library(dir.path() + "/mylib");
+    QVERIFY(!library.load());
+    QVERIFY(!library.isLoaded());
+    QVERIFY(!library.load());
+    QVERIFY(!library.isLoaded());
+
+    // now copy the actual lib file into our dir
+    QString actualLib = PREFIX "mylib" SUFFIX;
+    QVERIFY(QFile::copy(directory + '/' + actualLib, dir.filePath(actualLib)));
+
+    // try again, must succeed now
+    QVERIFY(library.load());
+    QVERIFY(library.isLoaded());
+    auto p = (VersionFunction)library.resolve("mylibversion");
+    QVERIFY(p);
+    QCOMPARE(p(), 2);
+    library.unload();
+}
+
 void tst_QLibrary::resolve_data()
 {
     QTest::addColumn<QString>("lib");