Xml: use new comparison helper macros

New comparison macros are used for following classes:
-QXmlStreamAttribute
-QXmlStreamNamespaceDeclaration
-QXmlStreamNotationDeclaration
-QXmlStreamEntityDeclaration

Replace public operators operator==(), operator!=() of
classes to friend methods comparesEqual();

Use QT_CORE_REMOVED_SINCE to get rid of current comparison methods
and replace them with a friend.

Add checkStreamNotationDeclarations()/checkStreamEntityDeclarations()
test-cases to test change.

Task-number: QTBUG-120300
Change-Id: I0b5642b2e23cc21ede7bc4888f0a9bddd6c08d07
Reviewed-by: Ivan Solovev <ivan.solovev@qt.io>
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>

3 files changed, 84 insertions, 39 deletions

diff --git a/src/corelib/compat/removed_api.cpp b/src/corelib/compat/removed_api.cpp
index f10eba5f7a..5dbe213cc8 100644
--- a/src/corelib/compat/removed_api.cpp
+++ b/src/corelib/compat/removed_api.cpp
@@ -1007,6 +1007,8 @@ int QObject::startTimer(std::chrono::milliseconds time, Qt::TimerType timerType)
 
 #include "qstring.h" // inlined API
 
+#include "qxmlstream.h" // inlined API
+
 // #include "qotherheader.h"
 // // implement removed functions from qotherheader.h
 // order sections alphabetically to reduce chances of merge conflicts
diff --git a/src/corelib/serialization/qxmlstream.cpp b/src/corelib/serialization/qxmlstream.cpp
index 39106e0791..5633002737 100644
--- a/src/corelib/serialization/qxmlstream.cpp
+++ b/src/corelib/serialization/qxmlstream.cpp
@@ -2331,6 +2331,8 @@ QXmlStreamAttributes QXmlStreamReader::attributes() const
 
     \ingroup xml-tools
 
+    \compares equality
+
     An attribute consists of an optionally empty namespaceUri(), a
     name(), a value(), and an isDefault() attribute.
 
@@ -2405,14 +2407,14 @@ QXmlStreamAttribute::QXmlStreamAttribute(const QString &qualifiedName, const QSt
    value following an ATTLIST declaration in the DTD; otherwise
    returns \c false.
 */
-/*! \fn bool QXmlStreamAttribute::operator==(const QXmlStreamAttribute &other) const
+/*! \fn bool QXmlStreamAttribute::operator==(const QXmlStreamAttribute &lhs, const QXmlStreamAttribute &rhs)
 
-    Compares this attribute with \a other and returns \c true if they are
+    Compares \a lhs attribute with \a rhs and returns \c true if they are
     equal; otherwise returns \c false.
  */
-/*! \fn bool QXmlStreamAttribute::operator!=(const QXmlStreamAttribute &other) const
+/*! \fn bool QXmlStreamAttribute::operator!=(const QXmlStreamAttribute &lhs, const QXmlStreamAttribute &rhs)
 
-    Compares this attribute with \a other and returns \c true if they are
+    Compares \a lhs attribute with \a rhs and returns \c true if they are
     not equal; otherwise returns \c false.
  */
 
@@ -2461,6 +2463,8 @@ QXmlStreamAttribute::QXmlStreamAttribute(const QString &qualifiedName, const QSt
 
     \ingroup xml-tools
 
+    \compares equality
+
     An notation declaration consists of a name(), a systemId(), and a publicId().
 */
 
@@ -2484,14 +2488,14 @@ Returns the system identifier.
 Returns the public identifier.
 */
 
-/*! \fn inline bool QXmlStreamNotationDeclaration::operator==(const QXmlStreamNotationDeclaration &other) const
+/*! \fn inline bool QXmlStreamNotationDeclaration::operator==(const QXmlStreamNotationDeclaration &lhs, const QXmlStreamNotationDeclaration &rhs)
 
-    Compares this notation declaration with \a other and returns \c true
+    Compares \a lhs notation declaration with \a rhs and returns \c true
     if they are equal; otherwise returns \c false.
  */
-/*! \fn inline bool QXmlStreamNotationDeclaration::operator!=(const QXmlStreamNotationDeclaration &other) const
+/*! \fn inline bool QXmlStreamNotationDeclaration::operator!=(const QXmlStreamNotationDeclaration &lhs, const QXmlStreamNotationDeclaration &rhs)
 
-    Compares this notation declaration with \a other and returns \c true
+    Compares \a lhs notation declaration with \a rhs and returns \c true
     if they are not equal; otherwise returns \c false.
  */
 
@@ -2511,16 +2515,18 @@ Returns the public identifier.
 
     \ingroup xml-tools
 
+    \compares equality
+
     An namespace declaration consists of a prefix() and a namespaceUri().
 */
-/*! \fn inline bool QXmlStreamNamespaceDeclaration::operator==(const QXmlStreamNamespaceDeclaration &other) const
+/*! \fn inline bool QXmlStreamNamespaceDeclaration::operator==(const QXmlStreamNamespaceDeclaration &lhs, const QXmlStreamNamespaceDeclaration &rhs)
 
-    Compares this namespace declaration with \a other and returns \c true
+    Compares \a lhs namespace declaration with \a rhs and returns \c true
     if they are equal; otherwise returns \c false.
  */
-/*! \fn inline bool QXmlStreamNamespaceDeclaration::operator!=(const QXmlStreamNamespaceDeclaration &other) const
+/*! \fn inline bool QXmlStreamNamespaceDeclaration::operator!=(const QXmlStreamNamespaceDeclaration &lhs, const QXmlStreamNamespaceDeclaration &rhs)
 
-    Compares this namespace declaration with \a other and returns \c true
+    Compares \a lhs namespace declaration with \a rhs and returns \c true
     if they are not equal; otherwise returns \c false.
  */
 
@@ -2577,6 +2583,7 @@ Returns the namespaceUri.
 
     \ingroup xml-tools
 
+    \compares equality
     An entity declaration consists of a name(), a notationName(), a
     systemId(), a publicId(), and a value().
 */
@@ -2609,14 +2616,14 @@ Returns the public identifier.
 Returns the entity's value.
 */
 
-/*! \fn bool QXmlStreamEntityDeclaration::operator==(const QXmlStreamEntityDeclaration &other) const
+/*! \fn bool QXmlStreamEntityDeclaration::operator==(const QXmlStreamEntityDeclaration &lhs, const QXmlStreamEntityDeclaration &rhs)
 
-    Compares this entity declaration with \a other and returns \c true if
+    Compares \a lhs entity declaration with \a rhs and returns \c true if
     they are equal; otherwise returns \c false.
  */
-/*! \fn bool QXmlStreamEntityDeclaration::operator!=(const QXmlStreamEntityDeclaration &other) const
+/*! \fn bool QXmlStreamEntityDeclaration::operator!=(const QXmlStreamEntityDeclaration &lhs, const QXmlStreamEntityDeclaration &rhs)
 
-    Compares this entity declaration with \a other and returns \c true if
+    Compares \a lhs entity declaration with \a rhs and returns \c true if
     they are not equal; otherwise returns \c false.
  */
 
diff --git a/src/corelib/serialization/qxmlstream.h b/src/corelib/serialization/qxmlstream.h
index e6dd25117a..7eeaa1c1cc 100644
--- a/src/corelib/serialization/qxmlstream.h
+++ b/src/corelib/serialization/qxmlstream.h
@@ -8,6 +8,7 @@
 
 #if QT_CONFIG(xmlstream)
 
+#include <QtCore/qcompare.h>
 #include <QtCore/qlist.h>
 #include <QtCore/qscopedpointer.h>
 #include <QtCore/qstring.h>
@@ -58,13 +59,23 @@ public:
     }
     inline QStringView value() const { return m_value; }
     inline bool isDefault() const { return m_isDefault; }
-    inline bool operator==(const QXmlStreamAttribute &other) const {
-        return (value() == other.value()
-                && (namespaceUri().isNull() ? (qualifiedName() == other.qualifiedName())
-                    : (namespaceUri() == other.namespaceUri() && name() == other.name())));
-    }
+#if QT_CORE_REMOVED_SINCE(6, 8)
+    inline bool operator==(const QXmlStreamAttribute &other) const
+    { return comparesEqual(*this, other); }
     inline bool operator!=(const QXmlStreamAttribute &other) const
-        { return !operator==(other); }
+    { return !operator==(other); }
+#endif
+
+private:
+    friend bool comparesEqual(const QXmlStreamAttribute &lhs,
+                              const QXmlStreamAttribute &rhs) noexcept
+    {
+        return (lhs.value() == rhs.value()
+                && (lhs.namespaceUri().isNull() ? (lhs.qualifiedName() == rhs.qualifiedName())
+                                                : (lhs.namespaceUri() == rhs.namespaceUri()
+                                                   && lhs.name() == rhs.name())));
+    }
+    Q_DECLARE_EQUALITY_COMPARABLE(QXmlStreamAttribute)
 };
 
 Q_DECLARE_TYPEINFO(QXmlStreamAttribute, Q_RELOCATABLE_TYPE);
@@ -111,11 +122,19 @@ public:
 
     inline QStringView prefix() const { return m_prefix; }
     inline QStringView namespaceUri() const { return m_namespaceUri; }
-    inline bool operator==(const QXmlStreamNamespaceDeclaration &other) const {
-        return (prefix() == other.prefix() && namespaceUri() == other.namespaceUri());
-    }
+#if QT_CORE_REMOVED_SINCE(6, 8)
+    inline bool operator==(const QXmlStreamNamespaceDeclaration &other) const
+    { return comparesEqual(*this, other); }
     inline bool operator!=(const QXmlStreamNamespaceDeclaration &other) const
-        { return !operator==(other); }
+    { return !operator==(other); }
+#endif
+private:
+    friend bool comparesEqual(const QXmlStreamNamespaceDeclaration &lhs,
+                              const QXmlStreamNamespaceDeclaration &rhs) noexcept
+    {
+        return (lhs.prefix() == rhs.prefix() && lhs.namespaceUri() == rhs.namespaceUri());
+    }
+    Q_DECLARE_EQUALITY_COMPARABLE(QXmlStreamNamespaceDeclaration)
 };
 
 Q_DECLARE_TYPEINFO(QXmlStreamNamespaceDeclaration, Q_RELOCATABLE_TYPE);
@@ -131,12 +150,20 @@ public:
     inline QStringView name() const { return m_name; }
     inline QStringView systemId() const { return m_systemId; }
     inline QStringView publicId() const { return m_publicId; }
-    inline bool operator==(const QXmlStreamNotationDeclaration &other) const {
-        return (name() == other.name() && systemId() == other.systemId()
-                && publicId() == other.publicId());
-    }
+#if QT_CORE_REMOVED_SINCE(6, 8)
+    inline bool operator==(const QXmlStreamNotationDeclaration &other) const
+    { return comparesEqual(*this, other); }
     inline bool operator!=(const QXmlStreamNotationDeclaration &other) const
-        { return !operator==(other); }
+    { return !operator==(other); }
+#endif
+private:
+    friend bool comparesEqual(const QXmlStreamNotationDeclaration &lhs,
+                              const QXmlStreamNotationDeclaration &rhs) noexcept
+    {
+        return (lhs.name() == rhs.name() && lhs.systemId() == rhs.systemId()
+                && lhs.publicId() == rhs.publicId());
+    }
+    Q_DECLARE_EQUALITY_COMPARABLE(QXmlStreamNotationDeclaration)
 };
 
 Q_DECLARE_TYPEINFO(QXmlStreamNotationDeclaration, Q_RELOCATABLE_TYPE);
@@ -154,15 +181,24 @@ public:
     inline QStringView systemId() const { return m_systemId; }
     inline QStringView publicId() const { return m_publicId; }
     inline QStringView value() const { return m_value; }
-    inline bool operator==(const QXmlStreamEntityDeclaration &other) const {
-        return (name() == other.name()
-                && notationName() == other.notationName()
-                && systemId() == other.systemId()
-                && publicId() == other.publicId()
-                && value() == other.value());
-    }
+#if QT_CORE_REMOVED_SINCE(6, 8)
+    inline bool operator==(const QXmlStreamEntityDeclaration &other) const
+    { return comparesEqual(*this, other); }
     inline bool operator!=(const QXmlStreamEntityDeclaration &other) const
-        { return !operator==(other); }
+    { return !operator==(other); }
+#endif
+
+private:
+    friend bool comparesEqual(const QXmlStreamEntityDeclaration &lhs,
+                              const QXmlStreamEntityDeclaration &rhs) noexcept
+    {
+        return (lhs.name() == rhs.name()
+                && lhs.notationName() == rhs.notationName()
+                && lhs.systemId() == rhs.systemId()
+                && lhs.publicId() == rhs.publicId()
+                && lhs.value() == rhs.value());
+    }
+    Q_DECLARE_EQUALITY_COMPARABLE(QXmlStreamEntityDeclaration)
 };
 
 Q_DECLARE_TYPEINFO(QXmlStreamEntityDeclaration, Q_RELOCATABLE_TYPE);