QMarginsF: add qFuzzyCompare and qFuzzyIsNull overloads

[ChangeLog][QtCore][QMarginsF] Added qFuzzyCompare and qFuzzyIsNull
overloads for QMarginsF

Task-number: QTBUG-120308
Change-Id: I7c1ceaa9ba544458738b71bf326395eef59e7a54
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>

src/corelib/tools/qmargins.cpp

@@ -754,6 +754,22 @@ QDebug operator<<(QDebug dbg, const QMargins &m)
     \sa QMarginsF(), QMargins::toMarginsF()
 */
 
+/*!
+    \fn bool QMarginsF::qFuzzyCompare(const QMarginsF &lhs, const QMarginsF &rhs)
+    \since 6.8
+
+    Returns \c true if \a lhs is approximately equal to \a rhs;
+    otherwise returns \c false.
+*/
+
+/*!
+    \fn bool QMarginsF::qFuzzyIsNull(const QMarginsF &margins)
+    \since 6.8
+
+    Returns \c true if all components of margsins \a margins are
+    approximately equal to zero; otherwise returns \c false.
+*/
+
 /*****************************************************************************
   QMarginsF stream functions
  *****************************************************************************/

src/corelib/tools/qmargins.h

@@ -302,7 +302,7 @@ private:
 
     QT_WARNING_PUSH
     QT_WARNING_DISABLE_FLOAT_COMPARE
-    friend constexpr bool comparesEqual(const QMarginsF &lhs, const QMarginsF &rhs) noexcept
+    friend constexpr bool qFuzzyCompare(const QMarginsF &lhs, const QMarginsF &rhs) noexcept
     {
         return ((!lhs.m_left || !rhs.m_left) ? qFuzzyIsNull(lhs.m_left - rhs.m_left)
                                              : qFuzzyCompare(lhs.m_left, rhs.m_left))
@@ -314,6 +314,16 @@ private:
                                                      : qFuzzyCompare(lhs.m_bottom, rhs.m_bottom));
     }
     QT_WARNING_POP
+    friend constexpr bool qFuzzyIsNull(const QMarginsF &m) noexcept
+    {
+        return qFuzzyIsNull(m.m_left) && qFuzzyIsNull(m.m_top)
+                && qFuzzyIsNull(m.m_right) && qFuzzyIsNull(m.m_bottom);
+    }
+
+    friend constexpr bool comparesEqual(const QMarginsF &lhs, const QMarginsF &rhs) noexcept
+    {
+        return qFuzzyCompare(lhs, rhs);
+    }
     Q_DECLARE_EQUALITY_COMPARABLE_LITERAL_TYPE(QMarginsF)
 
     friend constexpr bool comparesEqual(const QMarginsF &lhs, const QMargins &rhs) noexcept

tests/auto/corelib/tools/qmargins/tst_qmargins.cpp

@@ -48,6 +48,12 @@ private slots:
     void comparison_data();
     void comparison();
 
+    void fuzzyComparison_data();
+    void fuzzyComparison();
+
+    void isNull_data();
+    void isNull();
+
     void getSetCheck();
 #ifndef QT_NO_DATASTREAM
     void dataStreamCheck();
@@ -119,6 +125,45 @@ void tst_QMargins::comparison()
     QT_TEST_EQUALITY_OPS(lhs, rhsInt, mixedResult);
 }
 
+void tst_QMargins::fuzzyComparison_data()
+{
+    comparison_data();
+}
+
+void tst_QMargins::fuzzyComparison()
+{
+    QFETCH(const QMarginsF, lhs);
+    QFETCH(const QMarginsF, rhs);
+    QFETCH(const bool, floatResult);
+
+    QCOMPARE_EQ(qFuzzyCompare(lhs, rhs), floatResult);
+}
+
+void tst_QMargins::isNull_data()
+{
+    QTest::addColumn<QMarginsF>("margins");
+    QTest::addColumn<bool>("result");
+
+    QTest::newRow("null") << QMarginsF(0.0, 0.0, 0.0, 0.0) << true;
+    QTest::newRow("non_null_left") << QMarginsF(1.0, 0.0, 0.0, 0.0) << false;
+    QTest::newRow("non_null_top") << QMarginsF(0.0, 0.5, 0.0, 0.0) << false;
+    QTest::newRow("non_null_right") << QMarginsF(0.0, 0.0, -2.0, 0.0) << false;
+    QTest::newRow("non_null_bottom") << QMarginsF(0.0, 0.0, 0.0, -0.6) << false;
+    QTest::newRow("almost_null") << QMarginsF(qreal_min, -qreal_min, qreal_min, -qreal_min) << true;
+}
+
+void tst_QMargins::isNull()
+{
+    QFETCH(const QMarginsF, margins);
+    QFETCH(const bool, result);
+
+    QCOMPARE_EQ(margins.isNull(), result);
+    QCOMPARE_EQ(qFuzzyIsNull(margins), result);
+
+    const QMargins marginsInt = margins.toMargins();
+    QCOMPARE_EQ(marginsInt.isNull(), result);
+}
+
 // Testing get/set functions
 void tst_QMargins::getSetCheck()
 {