Added constructor to QJsonValue for const char *

For convenience, it reads more easily (and is somewhat expected) to
be able to add a string to a QJsonArray like you might with a
QVariantList: QJsonArray() << "string". Previously, QJsonValue provided
a private void* ctor to explicitly deny this case because it would
implicitly convert to a boolean. This ctor provides a const char* ctor
(much like QVariant) that interprets the incoming text as utf8 and
creates a String type QJsonValue.

[ChangeLog][QtCore][QJsonValue] Added constructor to QJsonValue for const char *

Change-Id: Icafa954d3da1fb264f9d0fd7cd1a1d2fbbe15095
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>
Reviewed-by: Lars Knoll <lars.knoll@digia.com>

2 files changed, 24 insertions, 3 deletions

diff --git a/src/corelib/json/qjsonvalue.cpp b/src/corelib/json/qjsonvalue.cpp
index 0a603b958a..c16824ebd2 100644
--- a/src/corelib/json/qjsonvalue.cpp
+++ b/src/corelib/json/qjsonvalue.cpp
@@ -175,7 +175,24 @@ QJsonValue::QJsonValue(qint64 n)
 QJsonValue::QJsonValue(const QString &s)
     : d(0), t(String)
 {
-    stringData = *(QStringData **)(&s);
+    stringDataFromQStringHelper(s);
+}
+
+/*!
+    \fn QJsonValue::QJsonValue(const char *s)
+
+    Creates a value of type String with value \a s, assuming
+    UTF-8 encoding of the input.
+
+    You can disable this constructor by defining \c
+    QT_NO_CAST_FROM_ASCII when you compile your applications.
+
+    \since 5.3
+ */
+
+void QJsonValue::stringDataFromQStringHelper(const QString &string)
+{
+    stringData = *(QStringData **)(&string);
     stringData->ref.ref();
 }
 
@@ -187,8 +204,7 @@ QJsonValue::QJsonValue(QLatin1String s)
 {
     // ### FIXME: Avoid creating the temp QString below
     QString str(s);
-    stringData = *(QStringData **)(&str);
-    stringData->ref.ref();
+    stringDataFromQStringHelper(str);
 }
 
 /*!
diff --git a/src/corelib/json/qjsonvalue.h b/src/corelib/json/qjsonvalue.h
index c0ecdd2b61..fe028990c0 100644
--- a/src/corelib/json/qjsonvalue.h
+++ b/src/corelib/json/qjsonvalue.h
@@ -82,6 +82,10 @@ public:
     QJsonValue(qint64 n);
     QJsonValue(const QString &s);
     QJsonValue(QLatin1String s);
+#ifndef QT_NO_CAST_FROM_ASCII
+    inline QT_ASCII_CAST_WARN QJsonValue(const char *s)
+        : d(0), t(String) { stringDataFromQStringHelper(QString::fromUtf8(s)); }
+#endif
     QJsonValue(const QJsonArray &a);
     QJsonValue(const QJsonObject &o);
 
@@ -123,6 +127,7 @@ private:
     friend Q_CORE_EXPORT QDebug operator<<(QDebug, const QJsonValue &);
 
     QJsonValue(QJsonPrivate::Data *d, QJsonPrivate::Base *b, const QJsonPrivate::Value& v);
+    void stringDataFromQStringHelper(const QString &string);
 
     void detach();