Fixes a crash in QDoubleSpinBox

Removing dubious intermediate detection code that also had a buffer
overflow.  The results were inconsistent and not dependable on.
Processing was inefficient and end value to user experience dubious.

Test cases that abused the former behaviour were changed to consider
input in an Intermediate where it was previously considered Invalid.

With this change, user input will mostly be considered in an
intermediate state, until it is effectively validated.

Task-number: 255019
Reviewed-by: Anders Bakken
(cherry picked from commit c5acc6ee80d9f429fc8f4d9dd3cca51f3efdf6d5)

3 files changed, 45 insertions, 222 deletions

diff --git a/src/gui/widgets/qspinbox.cpp b/src/gui/widgets/qspinbox.cpp
index 43e8c47..bd9b257 100644
--- a/src/gui/widgets/qspinbox.cpp
+++ b/src/gui/widgets/qspinbox.cpp
@@ -60,8 +60,6 @@ QT_BEGIN_NAMESPACE
 #  define QSBDEBUG if (false) qDebug
 #endif
 
-static bool isIntermediateValueHelper(qint64 num, qint64 minimum, qint64 maximum, qint64 *match = 0);
-
 class QSpinBoxPrivate : public QAbstractSpinBoxPrivate
 {
     Q_DECLARE_PUBLIC(QSpinBox)
@@ -73,7 +71,6 @@ public:
     virtual QString textFromValue(const QVariant &n) const;
     QVariant validateAndInterpret(QString &input, int &pos,
                                   QValidator::State &state) const;
-    bool isIntermediateValue(const QString &str) const;
     QChar thousand;
 
     inline void init() {
@@ -87,7 +84,6 @@ class QDoubleSpinBoxPrivate : public QAbstractSpinBoxPrivate
 public:
     QDoubleSpinBoxPrivate(QWidget *parent = 0);
     void emitSignals(EmitPolicy ep, const QVariant &);
-    bool isIntermediateValue(const QString &str) const;
 
     virtual QVariant valueFromText(const QString &n) const;
     virtual QString textFromValue(const QVariant &n) const;
@@ -975,51 +971,6 @@ QVariant QSpinBoxPrivate::valueFromText(const QString &text) const
 
 
 /*!
-  \internal
-
-  Return true if str can become a number which is between minimum and
-  maximum or false if this is not possible.
-*/
-
-bool QSpinBoxPrivate::isIntermediateValue(const QString &str) const
-{
-    const int num = q_func()->locale().toInt(str, 0, 10);
-    const int min = minimum.toInt();
-    const int max = maximum.toInt();
-
-    int numDigits = 0;
-    int digits[10];
-    int tmp = num;
-    if (tmp == 0) {
-        numDigits = 1;
-        digits[0] = 0;
-    } else {
-        tmp = num;
-        for (int i=0; tmp != 0; ++i) {
-            digits[numDigits++] = qAbs(tmp % 10);
-            tmp /= 10;
-        }
-    }
-
-    int failures = 0;
-    for (int number=min; /*number<=max*/; ++number) {
-        tmp = number;
-        for (int i=0; tmp != 0;) {
-            if (digits[i] == qAbs(tmp % 10)) {
-                if (++i == numDigits)
-                    return true;
-            }
-            tmp /= 10;
-        }
-        if (failures++ == 500000) //upper bound
-            return true;
-        if (number == max) // needed for INT_MAX
-            break;
-    }
-    return false;
-}
-
-/*!
     \internal Multi purpose function that parses input, sets state to
     the appropriate state and returns the value it will be interpreted
     as.
@@ -1073,9 +1024,8 @@ QVariant QSpinBoxPrivate::validateAndInterpret(QString &input, int &pos,
                 state = QValidator::Invalid;
                 QSBDEBUG() << __FILE__ << __LINE__<< "state is set to Invalid";
             } else {
-                state = isIntermediateValue(copy) ? QValidator::Intermediate : QValidator::Invalid;
-                QSBDEBUG() << __FILE__ << __LINE__<< "state is set to "
-                           << (state == QValidator::Intermediate ? "Intermediate" : "Acceptable");
+                state = QValidator::Intermediate;
+                QSBDEBUG() << __FILE__ << __LINE__<< "state is set to Intermediate";
             }
         }
     }
@@ -1135,105 +1085,6 @@ void QDoubleSpinBoxPrivate::emitSignals(EmitPolicy ep, const QVariant &old)
 }
 
 
-bool QDoubleSpinBoxPrivate::isIntermediateValue(const QString &str) const
-{
-    QSBDEBUG() << "input is" << str << minimum << maximum;
-    qint64 dec = 1;
-    for (int i=0; i<decimals; ++i)
-        dec *= 10;
-
-    const QLatin1Char dot('.');
-
-    // I know QString::number() uses CLocale so I use dot
-    const QString minstr = QString::number(minimum.toDouble(), 'f', decimals);
-    bool ok;
-    qint64 min_left = minstr.left(minstr.indexOf(dot)).toLongLong(&ok);
-    if (!ok)
-        return false;
-    qint64 min_right = minstr.mid(minstr.indexOf(dot) + 1).toLongLong();
-
-    const QString maxstr = QString::number(maximum.toDouble(), 'f', decimals);
-    qint64 max_left = maxstr.left(maxstr.indexOf(dot)).toLongLong(&ok);
-    if (!ok)
-        return true;
-    qint64 max_right = maxstr.mid(maxstr.indexOf(dot) + 1).toLongLong();
-
-    const int dotindex = str.indexOf(delimiter);
-    const bool negative = maximum.toDouble() < 0;
-    qint64 left = 0, right = 0;
-    bool doleft = true;
-    bool doright = true;
-    if (dotindex == -1) {
-        left = str.toLongLong();
-        doright = false;
-    } else if (dotindex == 0 || (dotindex == 1 && str.at(0) == QLatin1Char('+'))) {
-        if (negative) {
-            QSBDEBUG() << __FILE__ << __LINE__ << "returns false";
-            return false;
-        }
-        doleft = false;
-        right = str.mid(dotindex + 1).toLongLong();
-    } else if (dotindex == 1 && str.at(0) == QLatin1Char('-')) {
-        if (!negative) {
-            QSBDEBUG() << __FILE__ << __LINE__ << "returns false";
-            return false;
-        }
-        doleft = false;
-        right = str.mid(dotindex + 1).toLongLong();
-    } else {
-        left = str.left(dotindex).toLongLong();
-        if (dotindex == str.size() - 1) {
-            doright = false;
-        } else {
-            right = str.mid(dotindex + 1).toLongLong();
-        }
-    }
-    if ((left >= 0 && max_left < 0 && !str.startsWith(QLatin1Char('-'))) || (left < 0 && min_left >= 0)) {
-        QSBDEBUG("returns false 0");
-        return false;
-    }
-
-    qint64 match = min_left;
-    if (doleft && !isIntermediateValueHelper(left, min_left, max_left, &match)) {
-        QSBDEBUG() << __FILE__ << __LINE__ << "returns false";
-        return false;
-    }
-    if (doright) {
-        QSBDEBUG("match %lld min_left %lld max_left %lld", match, min_left, max_left);
-        if (!doleft) {
-            if (min_left == max_left) {
-                const bool ret = isIntermediateValueHelper(qAbs(left),
-                                                           negative ? max_right : min_right,
-                                                           negative ? min_right : max_right);
-                QSBDEBUG() << __FILE__ << __LINE__ << "returns" << ret;
-                return ret;
-            } else if (qAbs(max_left - min_left) == 1) {
-                const bool ret = isIntermediateValueHelper(qAbs(left), min_right, negative ? 0 : dec)
-                                 || isIntermediateValueHelper(qAbs(left), negative ? dec : 0, max_right);
-                QSBDEBUG() << __FILE__ << __LINE__ << "returns" << ret;
-                return ret;
-            } else {
-                const bool ret = isIntermediateValueHelper(qAbs(left), 0, dec);
-                QSBDEBUG() << __FILE__ << __LINE__ << "returns" << ret;
-                return ret;
-            }
-        }
-        if (match != min_left) {
-            min_right = negative ? dec : 0;
-        }
-        if (match != max_left) {
-            max_right = negative ? 0 : dec;
-        }
-        qint64 tmpl = negative ? max_right : min_right;
-        qint64 tmpr = negative ? min_right : max_right;
-        const bool ret = isIntermediateValueHelper(right, tmpl, tmpr);
-        QSBDEBUG() << __FILE__ << __LINE__ << "returns" << ret;
-        return ret;
-    }
-    QSBDEBUG() << __FILE__ << __LINE__ << "returns true";
-    return true;
-}
-
 /*!
     \internal
     \reimp
@@ -1402,9 +1253,8 @@ QVariant QDoubleSpinBoxPrivate::validateAndInterpret(QString &input, int &pos,
                 state = QValidator::Invalid;
                 QSBDEBUG() << __FILE__ << __LINE__<< "state is set to Invalid";
             } else {
-                state = isIntermediateValue(copy) ? QValidator::Intermediate : QValidator::Invalid;
-                QSBDEBUG() << __FILE__ << __LINE__<< "state is set to "
-                           << (state == QValidator::Intermediate ? "Intermediate" : "Acceptable");
+                state = QValidator::Intermediate;
+                QSBDEBUG() << __FILE__ << __LINE__<< "state is set to Intermediate";
             }
         }
     }
@@ -1462,62 +1312,6 @@ QString QDoubleSpinBoxPrivate::textFromValue(const QVariant &f) const
     Use minimum() instead.
 */
 
-/*!
-    \internal Returns whether \a str is a string which value cannot be
-    parsed but still might turn into something valid.
-*/
-
-static bool isIntermediateValueHelper(qint64 num, qint64 min, qint64 max, qint64 *match)
-{
-    QSBDEBUG("%lld %lld %lld", num, min, max);
-
-    if (num >= min && num <= max) {
-        if (match)
-            *match = num;
-        QSBDEBUG("returns true 0");
-        return true;
-    }
-    qint64 tmp = num;
-
-    int numDigits = 0;
-    int digits[10];
-    if (tmp == 0) {
-        numDigits = 1;
-        digits[0] = 0;
-    } else {
-        tmp = qAbs(num);
-        for (int i=0; tmp > 0; ++i) {
-            digits[numDigits++] = tmp % 10;
-            tmp /= 10;
-        }
-    }
-
-    int failures = 0;
-    qint64 number;
-    for (number=max; number>=min; --number) {
-        tmp = qAbs(number);
-        for (int i=0; tmp > 0;) {
-            if (digits[i] == (tmp % 10)) {
-                if (++i == numDigits) {
-                    if (match)
-                        *match = number;
-                    QSBDEBUG("returns true 1");
-                    return true;
-                }
-            }
-            tmp /= 10;
-        }
-        if (failures++ == 500000) { //upper bound
-            if (match)
-                *match = num;
-            QSBDEBUG("returns true 2");
-            return true;
-        }
-    }
-    QSBDEBUG("returns false");
-    return false;
-}
-
 /*! \reimp */
 bool QSpinBox::event(QEvent *event)
 {
diff --git a/tests/auto/qdoublespinbox/tst_qdoublespinbox.cpp b/tests/auto/qdoublespinbox/tst_qdoublespinbox.cpp
index 43d5d46..020159b 100644
--- a/tests/auto/qdoublespinbox/tst_qdoublespinbox.cpp
+++ b/tests/auto/qdoublespinbox/tst_qdoublespinbox.cpp
@@ -52,6 +52,9 @@
 
 #include <qlineedit.h>
 #include <qdebug.h>
+
+#include "../../shared/util.h"
+
 //TESTED_CLASS=
 //TESTED_FILES=gui/widgets/qspinbox.h gui/widgets/qspinbox.cpp gui/widgets/qabstractspinbox.cpp gui/widgets/qabstractspinbox_p.h gui/widgets/qabstractspinbox.h
 
@@ -142,6 +145,7 @@ private slots:
     void task224497_fltMax();
 
     void task221221();
+    void task255471_decimalsValidation();
 
 public slots:
     void valueChangedHelper(const QString &);
@@ -665,7 +669,7 @@ void tst_QDoubleSpinBox::valueFromTextAndValidate_data()
     QTest::addColumn<int>("language");
     QTest::addColumn<QString>("expectedText"); // if empty we don't check
 
-    QTest::newRow("data0") << QString("2.2") << Invalid << 3.0 << 5.0 << (int)QLocale::C << QString();
+    QTest::newRow("data0") << QString("2.2") << Intermediate << 3.0 << 5.0 << (int)QLocale::C << QString();
     QTest::newRow("data1") << QString() << Intermediate << 0.0 << 100.0 << (int)QLocale::C << QString();
     QTest::newRow("data2") << QString("asd") << Invalid << 0.0 << 100.0 << (int)QLocale::C << QString();
     QTest::newRow("data3") << QString("2.2") << Acceptable << 0.0 << 100.0 << (int)QLocale::C << QString();
@@ -682,20 +686,20 @@ void tst_QDoubleSpinBox::valueFromTextAndValidate_data()
     QTest::newRow("data14") << QString("1, ") << Acceptable << 0.0 << 100.0 << (int)QLocale::Norwegian << QString("1,");
     QTest::newRow("data15") << QString("1, ") << Invalid << 0.0 << 100.0 << (int)QLocale::C << QString();
     QTest::newRow("data16") << QString("2") << Intermediate << 100.0 << 102.0 << (int)QLocale::C << QString();
-    QTest::newRow("data17") << QString("22.0") << Invalid << 100.0 << 102.0 << (int)QLocale::C << QString();
+    QTest::newRow("data17") << QString("22.0") << Intermediate << 100.0 << 102.0 << (int)QLocale::C << QString();
     QTest::newRow("data18") << QString("12.0") << Intermediate << 100.0 << 102.0 << (int)QLocale::C << QString();
-    QTest::newRow("data19") << QString("12.2") << Invalid << 100. << 102.0 << (int)QLocale::C << QString();
-    QTest::newRow("data20") << QString("21.") << Invalid << 100.0 << 102.0 << (int)QLocale::C << QString();
-    QTest::newRow("data21") << QString("-21.") << Invalid << -102.0 << -100.0 << (int)QLocale::C << QString();
+    QTest::newRow("data19") << QString("12.2") << Intermediate << 100. << 102.0 << (int)QLocale::C << QString();
+    QTest::newRow("data20") << QString("21.") << Intermediate << 100.0 << 102.0 << (int)QLocale::C << QString();
+    QTest::newRow("data21") << QString("-21.") << Intermediate << -102.0 << -100.0 << (int)QLocale::C << QString();
     QTest::newRow("data22") << QString("-12.") << Intermediate << -102.0 << -100.0 << (int)QLocale::C << QString();
-    QTest::newRow("data23") << QString("-11.11") << Invalid << -102.0 << -101.2 << (int)QLocale::C << QString();
+    QTest::newRow("data23") << QString("-11.11") << Intermediate << -102.0 << -101.2 << (int)QLocale::C << QString();
     QTest::newRow("data24") << QString("-11.4") << Intermediate << -102.0 << -101.3 << (int)QLocale::C << QString();
     QTest::newRow("data25") << QString("11.400") << Invalid << 0.0 << 100.0 << (int)QLocale::C << QString();
     QTest::newRow("data26") << QString(".4") << Intermediate << 0.45 << 0.5 << (int)QLocale::C << QString();
     QTest::newRow("data27") << QString("+.4") << Intermediate << 0.45 << 0.5 << (int)QLocale::C << QString();
     QTest::newRow("data28") << QString("-.4") << Intermediate << -0.5 << -0.45 << (int)QLocale::C << QString();
     QTest::newRow("data29") << QString(".4") << Intermediate << 1.0 << 2.4 << (int)QLocale::C << QString();
-    QTest::newRow("data30") << QString("-.4") << Invalid << -2.3 << -1.9 << (int)QLocale::C << QString();
+    QTest::newRow("data30") << QString("-.4") << Intermediate << -2.3 << -1.9 << (int)QLocale::C << QString();
     QTest::newRow("data31") << QString("-42") << Invalid << -2.43 << -1.0 << (int)QLocale::C << QString();
     QTest::newRow("data32") << QString("-4") << Invalid << -1.4 << -1.0 << (int)QLocale::C << QString();
     QTest::newRow("data33") << QString("-42") << Invalid << -1.4 << -1.0 << (int)QLocale::C << QString();
@@ -709,7 +713,7 @@ void tst_QDoubleSpinBox::valueFromTextAndValidate_data()
     QTest::newRow("data41") << QString("103.") << Invalid << -102.0 << 11.0 << (int)QLocale::C << QString();
     QTest::newRow("data42") << QString("122") << Invalid << 10.0 << 12.2 << (int)QLocale::C << QString();
     QTest::newRow("data43") << QString("-2.2") << Intermediate << -12.2 << -3.2 << (int)QLocale::C << QString();
-    QTest::newRow("data44") << QString("-2.20") << Invalid << -12.1 << -3.2 << (int)QLocale::C << QString();
+    QTest::newRow("data44") << QString("-2.20") << Intermediate << -12.1 << -3.2 << (int)QLocale::C << QString();
     QTest::newRow("data45") << QString("200,2") << Invalid << 0.0 << 1000.0 << (int)QLocale::C << QString();
     QTest::newRow("data46") << QString("200,2") << Acceptable << 0.0 << 1000.0 << (int)QLocale::German << QString();
     QTest::newRow("data47") << QString("2.2") << Acceptable << 0.0 << 1000.0 << (int)QLocale::C << QString();
@@ -1003,6 +1007,31 @@ void tst_QDoubleSpinBox::task221221()
     QCOMPARE(spin.text(), QLatin1String("1"));
 }
 
+void tst_QDoubleSpinBox::task255471_decimalsValidation()
+{
+    // QDoubleSpinBox shouldn't crash with large numbers of decimals. Even if
+    // the results are useless ;-)
+    for (int i = 0; i < 32; ++i)
+    {
+        QDoubleSpinBox spinBox;
+        spinBox.setDecimals(i);
+        spinBox.setMinimum(0.3);
+        spinBox.setMaximum(12);
+
+        spinBox.show();
+        QTRY_VERIFY(spinBox.isVisible());
+        spinBox.setFocus();
+        QTRY_VERIFY(spinBox.hasFocus());
+
+        QTest::keyPress(&spinBox, Qt::Key_Right);
+        QTest::keyPress(&spinBox, Qt::Key_Right);
+        QTest::keyPress(&spinBox, Qt::Key_Delete);
+
+        // Don't crash!
+        QTest::keyPress(&spinBox, Qt::Key_2);
+    }
+}
+
 
 QTEST_MAIN(tst_QDoubleSpinBox)
 #include "tst_qdoublespinbox.moc"
diff --git a/tests/auto/qspinbox/tst_qspinbox.cpp b/tests/auto/qspinbox/tst_qspinbox.cpp
index c9cbc4b..8709b86 100644
--- a/tests/auto/qspinbox/tst_qspinbox.cpp
+++ b/tests/auto/qspinbox/tst_qspinbox.cpp
@@ -643,21 +643,21 @@ void tst_QSpinBox::valueFromTextAndValidate_data()
     QTest::addColumn<int>("maxi");
     QTest::addColumn<QString>("expectedText"); // if empty we don't check
 
-    QTest::newRow("data0") << QString("2") << Invalid << 3 << 5 << QString();
+    QTest::newRow("data0") << QString("2") << Intermediate << 3 << 5 << QString();
     QTest::newRow("data1") << QString() << Intermediate << 0 << 100 << QString();
     QTest::newRow("data2") << QString("asd") << Invalid << 0 << 100 << QString();
     QTest::newRow("data3") << QString("2") << Acceptable << 0 << 100 << QString();
     QTest::newRow("data4") << QString() << Intermediate << 0 << 1 << QString();
     QTest::newRow("data5") << QString() << Invalid << 0 << 0 << QString();
     QTest::newRow("data5") << QString("5") << Intermediate << 2004 << 2005 << QString();
-    QTest::newRow("data6") << QString("50") << Invalid << 2004 << 2005 << QString();
+    QTest::newRow("data6") << QString("50") << Intermediate << 2004 << 2005 << QString();
     QTest::newRow("data7") << QString("205") << Intermediate << 2004 << 2005 << QString();
     QTest::newRow("data8") << QString("2005") << Acceptable << 2004 << 2005 << QString();
-    QTest::newRow("data9") << QString("3") << Invalid << 2004 << 2005 << QString();
+    QTest::newRow("data9") << QString("3") << Intermediate << 2004 << 2005 << QString();
     QTest::newRow("data10") << QString("-") << Intermediate << -20 << -10 << QString();
     QTest::newRow("data11") << QString("-1") << Intermediate << -20 << -10 << QString();
     QTest::newRow("data12") << QString("-5") << Intermediate << -20 << -10 << QString();
-    QTest::newRow("data13") << QString("-5") << Invalid << -20 << -16 << QString();
+    QTest::newRow("data13") << QString("-5") << Intermediate << -20 << -16 << QString();
     QTest::newRow("data14") << QString("-2") << Intermediate << -20 << -16 << QString();
     QTest::newRow("data15") << QString("2") << Invalid << -20 << -16 << QString();
     QTest::newRow("data16") << QString() << Intermediate << -20 << -16 << QString();