QNetworkRequest: make the default ctor implicit

As in QVarLengthArray (c34242c679aaea6ee1badf6c1e5f274f925f5f50), this will
probably bite someone someday, so fix it before there's a bug report.

Use ctor delegation to keep code size increase small.

There's also the benefit that default-constructing a QNetworkRequest now
no longer creates an expensive QUrl object just to destroy it unused again.

Add an auto-test.

Change-Id: I5ceb5402ca3946048d695244d1b1c36564a1e80a
Reviewed-by: Timur Pocheptsov <timur.pocheptsov@qt.io>

1 files changed, 7 insertions, 0 deletions

diff --git a/tests/auto/network/access/qnetworkrequest/tst_qnetworkrequest.cpp b/tests/auto/network/access/qnetworkrequest/tst_qnetworkrequest.cpp
index 7a3def410a..6637be0174 100644
--- a/tests/auto/network/access/qnetworkrequest/tst_qnetworkrequest.cpp
+++ b/tests/auto/network/access/qnetworkrequest/tst_qnetworkrequest.cpp
@@ -41,6 +41,7 @@ class tst_QNetworkRequest: public QObject
 private slots:
     void ctor_data();
     void ctor();
+    void implicitDefaultCtor();
     void setUrl_data();
     void setUrl();
     void setRawHeader_data();
@@ -78,6 +79,12 @@ void tst_QNetworkRequest::ctor()
     }
 }
 
+void tst_QNetworkRequest::implicitDefaultCtor()
+{
+    QNetworkRequest r = {};
+    Q_UNUSED(r);
+}
+
 void tst_QNetworkRequest::setUrl_data()
 {
     ctor_data();