qputenv: port to QByteArrayView

The vast majority of in-tree users pass simple and short C string
literals as the value. By porting to QByteArrayView, we document that
we'll accept non-NUL-terminated data, and do the NUL-termination
internally, using SSO'ed std::string, saving memory allocations in the
common case of short strings.

I didn't bother to check which direction std::string takes for
nullptrs these days (there was a change accepted in that area for
C++20 or 23), so play it safe and protect against them.

Follow-up to

Task-number: QTBUG-105302
Change-Id: I2369acc62f1d5cbc26135396cfe0602d8c75300c
Reviewed-by: Sona Kurazyan <sona.kurazyan@qt.io>
Reviewed-by: Mårten Nordheim <marten.nordheim@qt.io>
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>

2 files changed, 5 insertions, 5 deletions

diff --git a/tests/auto/corelib/io/qloggingcategory/tst_qloggingcategory.cpp b/tests/auto/corelib/io/qloggingcategory/tst_qloggingcategory.cpp
index a0a9bb940e..3ba6de20a9 100644
--- a/tests/auto/corelib/io/qloggingcategory/tst_qloggingcategory.cpp
+++ b/tests/auto/corelib/io/qloggingcategory/tst_qloggingcategory.cpp
@@ -181,7 +181,7 @@ private slots:
     void initTestCase()
     {
         qputenv("XDG_CONFIG_DIRS", "/does/not/exist");
-        qputenv("QT_MESSAGE_PATTERN", QByteArray("%{category}: %{type},%{message}"));
+        qputenv("QT_MESSAGE_PATTERN", "%{category}: %{type},%{message}");
         oldMessageHandler = qInstallMessageHandler(myCustomMessageHandler);
         // Create configuration
         _config = new Configuration();
diff --git a/tests/auto/corelib/io/qstandardpaths/tst_qstandardpaths.cpp b/tests/auto/corelib/io/qstandardpaths/tst_qstandardpaths.cpp
index 2c0500eec9..b2bb14180e 100644
--- a/tests/auto/corelib/io/qstandardpaths/tst_qstandardpaths.cpp
+++ b/tests/auto/corelib/io/qstandardpaths/tst_qstandardpaths.cpp
@@ -64,10 +64,10 @@ private:
         qputenv("XDG_DATA_DIRS", QFile::encodeName(m_globalAppDir));
     }
     void setDefaultLocations() {
-        qputenv("XDG_CONFIG_HOME", QByteArray());
-        qputenv("XDG_CONFIG_DIRS", QByteArray());
-        qputenv("XDG_DATA_HOME", QByteArray());
-        qputenv("XDG_DATA_DIRS", QByteArray());
+        qputenv("XDG_CONFIG_HOME", nullptr);
+        qputenv("XDG_CONFIG_DIRS", nullptr);
+        qputenv("XDG_DATA_HOME", nullptr);
+        qputenv("XDG_DATA_DIRS", nullptr);
     }
 #endif