QSize(F): use comparison helper macros

Also explicitly add QSizeF vs QSize comparison. Previously such
comparison was implicitly converting QSize to QSizeF, and doing the
fuzzy comparison. We have to keep the old behavior to avoid
breaking user code, so use fuzzy comparison in the new operators
as well.

As a drive-by: put all the hidden friends in the private section.

Done-with: Ivan Solovev <ivan.solovev@qt.io>
Task-number: QTBUG-120308
Change-Id: Ia52adc97c557e475b19f5c16f9dd8c992637280e
Reviewed-by: Edward Welbourne <edward.welbourne@qt.io>
Reviewed-by: Ivan Solovev <ivan.solovev@qt.io>
Reviewed-by: Tatiana Borisova <tatiana.borisova@qt.io>

6 files changed, 108 insertions, 14 deletions

diff --git a/src/corelib/tools/qsize.cpp b/src/corelib/tools/qsize.cpp
index d5e8e4c71b..0165a4095c 100644
--- a/src/corelib/tools/qsize.cpp
+++ b/src/corelib/tools/qsize.cpp
@@ -266,15 +266,15 @@ QSize QSize::scaled(const QSize &s, Qt::AspectRatioMode mode) const noexcept
 */
 
 /*!
-    \fn bool QSize::operator==(const QSize &s1, const QSize &s2)
+    \fn bool QSize::operator==(const QSize &lhs, const QSize &rhs)
 
-    Returns \c true if \a s1 and \a s2 are equal; otherwise returns \c false.
+    Returns \c true if \a lhs and \a rhs are equal; otherwise returns \c false.
 */
 
 /*!
-    \fn bool QSize::operator!=(const QSize &s1, const QSize &s2)
+    \fn bool QSize::operator!=(const QSize &lhs, const QSize &rhs)
 
-    Returns \c true if \a s1 and \a s2 are different; otherwise returns \c false.
+    Returns \c true if \a lhs and \a rhs are different; otherwise returns \c false.
 */
 
 /*!
@@ -714,9 +714,9 @@ QSizeF QSizeF::scaled(const QSizeF &s, Qt::AspectRatioMode mode) const noexcept
 */
 
 /*!
-    \fn bool QSizeF::operator==(const QSizeF &s1, const QSizeF &s2)
+    \fn bool QSizeF::operator==(const QSizeF &lhs, const QSizeF &rhs)
 
-    Returns \c true if \a s1 and \a s2 are approximately equal; otherwise
+    Returns \c true if \a lhs and \a rhs are approximately equal; otherwise
     returns false.
 
     \warning This function does not check for strict equality; instead,
@@ -726,9 +726,9 @@ QSizeF QSizeF::scaled(const QSizeF &s, Qt::AspectRatioMode mode) const noexcept
 */
 
 /*!
-    \fn bool QSizeF::operator!=(const QSizeF &s1, const QSizeF &s2)
+    \fn bool QSizeF::operator!=(const QSizeF &lhs, const QSizeF &rhs)
 
-    Returns \c true if \a s1 and \a s2 are sufficiently different; otherwise
+    Returns \c true if \a lhs and \a rhs are sufficiently different; otherwise
     returns \c false.
 
     \warning This function does not check for strict inequality; instead,
diff --git a/src/corelib/tools/qsize.h b/src/corelib/tools/qsize.h
index a5eaf34afe..604f110ebe 100644
--- a/src/corelib/tools/qsize.h
+++ b/src/corelib/tools/qsize.h
@@ -59,10 +59,10 @@ public:
     constexpr inline QSize &operator*=(qreal c) noexcept;
     inline QSize &operator/=(qreal c);
 
-    friend inline constexpr bool operator==(const QSize &s1, const QSize &s2) noexcept
+private:
+    friend constexpr bool comparesEqual(const QSize &s1, const QSize &s2) noexcept
     { return s1.wd == s2.wd && s1.ht == s2.ht; }
-    friend inline constexpr bool operator!=(const QSize &s1, const QSize &s2) noexcept
-    { return s1.wd != s2.wd || s1.ht != s2.ht; }
+    Q_DECLARE_EQUALITY_COMPARABLE_LITERAL_TYPE(QSize)
     friend inline constexpr QSize operator+(const QSize &s1, const QSize &s2) noexcept
     { return QSize(s1.wd + s2.wd, s1.ht + s2.ht); }
     friend inline constexpr QSize operator-(const QSize &s1, const QSize &s2) noexcept
@@ -75,6 +75,7 @@ public:
     { Q_ASSERT(!qFuzzyIsNull(c)); return QSize(qRound(s.wd / c), qRound(s.ht / c)); }
     friend inline constexpr size_t qHash(const QSize &, size_t) noexcept;
 
+public:
 #if defined(Q_OS_DARWIN) || defined(Q_QDOC)
     [[nodiscard]] CGSize toCGSize() const noexcept;
 #endif
@@ -242,16 +243,19 @@ public:
     constexpr inline QSizeF &operator*=(qreal c) noexcept;
     inline QSizeF &operator/=(qreal c);
 
+private:
     QT_WARNING_PUSH
     QT_WARNING_DISABLE_FLOAT_COMPARE
-    friend constexpr inline bool operator==(const QSizeF &s1, const QSizeF &s2)
+    friend constexpr bool comparesEqual(const QSizeF &s1, const QSizeF &s2) noexcept
     {
         return ((!s1.wd || !s2.wd) ? qFuzzyIsNull(s1.wd - s2.wd) : qFuzzyCompare(s1.wd, s2.wd))
             && ((!s1.ht || !s2.ht) ? qFuzzyIsNull(s1.ht - s2.ht) : qFuzzyCompare(s1.ht, s2.ht));
     }
     QT_WARNING_POP
-    friend constexpr inline bool operator!=(const QSizeF &s1, const QSizeF &s2)
-    { return !(s1 == s2); }
+    Q_DECLARE_EQUALITY_COMPARABLE_LITERAL_TYPE(QSizeF)
+    friend constexpr bool comparesEqual(const QSizeF &lhs, const QSize &rhs) noexcept
+    { return comparesEqual(lhs, rhs.toSizeF()); }
+    Q_DECLARE_EQUALITY_COMPARABLE_LITERAL_TYPE(QSizeF, QSize)
     friend constexpr inline QSizeF operator+(const QSizeF &s1, const QSizeF &s2) noexcept
     { return QSizeF(s1.wd + s2.wd, s1.ht + s2.ht); }
     friend constexpr inline QSizeF operator-(const QSizeF &s1, const QSizeF &s2) noexcept
@@ -263,6 +267,7 @@ public:
     friend inline QSizeF operator/(const QSizeF &s, qreal c)
     { Q_ASSERT(!qFuzzyIsNull(c)); return QSizeF(s.wd / c, s.ht / c); }
 
+public:
     constexpr inline QSize toSize() const noexcept;
 
 #if defined(Q_OS_DARWIN) || defined(Q_QDOC)
diff --git a/tests/auto/corelib/tools/qsize/CMakeLists.txt b/tests/auto/corelib/tools/qsize/CMakeLists.txt
index 91de696ddd..4a4c96b52c 100644
--- a/tests/auto/corelib/tools/qsize/CMakeLists.txt
+++ b/tests/auto/corelib/tools/qsize/CMakeLists.txt
@@ -14,4 +14,6 @@ endif()
 qt_internal_add_test(tst_qsize
     SOURCES
         tst_qsize.cpp
+    LIBRARIES
+        Qt::TestPrivate
 )
diff --git a/tests/auto/corelib/tools/qsize/tst_qsize.cpp b/tests/auto/corelib/tools/qsize/tst_qsize.cpp
index c9699c5e76..d379275dd8 100644
--- a/tests/auto/corelib/tools/qsize/tst_qsize.cpp
+++ b/tests/auto/corelib/tools/qsize/tst_qsize.cpp
@@ -24,6 +24,7 @@ CHECK(const &&);
 #undef CHECK
 
 #include <QTest>
+#include <QtTest/private/qcomparisontesthelper_p.h>
 #include <qsize.h>
 
 #include <array>
@@ -34,6 +35,10 @@ class tst_QSize : public QObject
 {
     Q_OBJECT
 private slots:
+    void compareCompiles();
+    void compare_data();
+    void compare();
+
     void getSetCheck();
     void scale();
 
@@ -55,6 +60,38 @@ private slots:
     void structuredBinding();
 };
 
+void tst_QSize::compareCompiles()
+{
+    QTestPrivate::testEqualityOperatorsCompile<QSize>();
+}
+
+void tst_QSize::compare_data()
+{
+    QTest::addColumn<QSize>("lhs");
+    QTest::addColumn<QSize>("rhs");
+    QTest::addColumn<bool>("result");
+
+    auto row = [](QSize lhs, QSize rhs, bool res) {
+        QTest::addRow("(%d, %d) vs (%d, %d)", lhs.width(), lhs.height(), rhs.width(), rhs.height())
+                << lhs << rhs << res;
+    };
+
+    row(QSize(0, 0), QSize(0, 0), true);
+    row(QSize(1, 0), QSize(0, 1), false);
+    row(QSize(-1, -1), QSize(-1, -1), true);
+    row(QSize(-1, -1), QSize(1, 1), false);
+    row(QSize(INT_MIN, INT_MAX), QSize(INT_MAX, INT_MIN), false);
+}
+
+void tst_QSize::compare()
+{
+    QFETCH(QSize, lhs);
+    QFETCH(QSize, rhs);
+    QFETCH(bool, result);
+
+    QT_TEST_EQUALITY_OPS(lhs, rhs, result);
+}
+
 // Testing get/set functions
 void tst_QSize::getSetCheck()
 {
diff --git a/tests/auto/corelib/tools/qsizef/CMakeLists.txt b/tests/auto/corelib/tools/qsizef/CMakeLists.txt
index 9adaafe2ea..d8a1c7f46e 100644
--- a/tests/auto/corelib/tools/qsizef/CMakeLists.txt
+++ b/tests/auto/corelib/tools/qsizef/CMakeLists.txt
@@ -14,4 +14,6 @@ endif()
 qt_internal_add_test(tst_qsizef
     SOURCES
         tst_qsizef.cpp
+    LIBRARIES
+        Qt::TestPrivate
 )
diff --git a/tests/auto/corelib/tools/qsizef/tst_qsizef.cpp b/tests/auto/corelib/tools/qsizef/tst_qsizef.cpp
index ee33fa13b6..12e30dfa57 100644
--- a/tests/auto/corelib/tools/qsizef/tst_qsizef.cpp
+++ b/tests/auto/corelib/tools/qsizef/tst_qsizef.cpp
@@ -24,14 +24,21 @@ CHECK(const &&);
 #undef CHECK
 
 #include <QTest>
+#include <QtTest/private/qcomparisontesthelper_p.h>
 #include <qsize.h>
 
 Q_DECLARE_METATYPE(QMarginsF)
 
+static constexpr qreal qreal_min = std::numeric_limits<qreal>::min();
+
 class tst_QSizeF : public QObject
 {
     Q_OBJECT
 private slots:
+    void compareCompiles();
+    void compare_data();
+    void compare();
+
     void isNull_data();
     void isNull();
 
@@ -52,6 +59,47 @@ private slots:
     void structuredBinding();
 };
 
+void tst_QSizeF::compareCompiles()
+{
+    QTestPrivate::testEqualityOperatorsCompile<QSizeF>();
+    QTestPrivate::testEqualityOperatorsCompile<QSizeF, QSize>();
+}
+
+void tst_QSizeF::compare_data()
+{
+    QTest::addColumn<QSizeF>("lhs");
+    QTest::addColumn<QSizeF>("rhs");
+    QTest::addColumn<bool>("result");
+    QTest::addColumn<bool>("mixedResult");
+
+    auto row = [&](QSizeF lhs, QSizeF rhs, bool res, bool mixedRes) {
+        QString str;
+        QDebug dbg(&str);
+        dbg.nospace() << "(" << lhs.width() << ", " << lhs.height() << ") vs "
+                      << "(" << rhs.width() << ", " << rhs.height() << ")";
+        QTest::addRow("%s", str.toLatin1().constData()) << lhs << rhs << res << mixedRes;
+    };
+
+    row(QSizeF(0.0, 0.0), QSizeF(0.0, 0.0), true, true);
+    row(QSizeF(1.0, 2.0), QSizeF(1.0, 2.0), true, true);
+    row(QSizeF(1.0, -1.0), QSizeF(-1.0, 1.0), false, false);
+    row(QSizeF(0.1, 1.1), QSizeF(0.1, 1.1), true, false);
+    row(QSizeF(qreal_min, 0.0), QSizeF(0.0, -qreal_min), true, true);
+}
+
+void tst_QSizeF::compare()
+{
+    QFETCH(QSizeF, lhs);
+    QFETCH(QSizeF, rhs);
+    QFETCH(bool, result);
+    QFETCH(bool, mixedResult);
+
+    QT_TEST_EQUALITY_OPS(lhs, rhs, result);
+
+    const QSize rhsFixed = rhs.toSize();
+    QT_TEST_EQUALITY_OPS(lhs, rhsFixed, mixedResult);
+}
+
 void tst_QSizeF::isNull_data()
 {
     QTest::addColumn<qreal>("width");