qqmlscriptstring.cpp

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// Copyright (C) 2016 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
// Qt-Security score:significant
 
#include "qqmlscriptstring.h"
#include "qqmlscriptstring_p.h"
 
QT_BEGIN_NAMESPACE
 
/*!
\class QQmlScriptString
\brief The QQmlScriptString class encapsulates a script and its context.
\inmodule QtQml
 
QQmlScriptString is used to create QObject properties that accept a script "assignment" from QML.
 
Normally, the following QML would result in a binding being established for the \c script
property; i.e. \c script would be assigned the value obtained from running \c {myObj.value = Math.max(myValue, 100)}
 
\qml
MyType {
    script: myObj.value = Math.max(myValue, 100)
}
\endqml
 
If instead the property had a type of QQmlScriptString,
the script itself -- \e {myObj.value = Math.max(myValue, 100)} -- would be passed to the \c script property
and the class could choose how to handle it. Typically, the class will evaluate
the script at some later time using a QQmlExpression.
 
\code
QQmlExpression expr(scriptString);
expr.evaluate();
\endcode
 
\note A QQmlScriptString can always be evaluated through a QQmlExpression, but
its source code is not guaranteed to be retrievable. If the QML module is
compiled ahead of time, the source code of non-literal script strings may be
discarded and cannot be recovered via \l QQmlExpression::expression(). Avoid
relying on the textual form of a script string; evaluate it instead.
 
\sa QQmlExpression
*/
 
const QQmlScriptStringPrivate* QQmlScriptStringPrivate::get(const QQmlScriptString &script)
{
    return script.d.constData();
}
 
QQmlScriptString QQmlScriptStringPrivate::create(const QString &script, QQmlContext *context,
    QObject *scope)
{
    return QQmlScriptString(script, context, scope);
}
 
/*!
Constructs an empty instance.
*/
QQmlScriptString::QQmlScriptString()
:  d()
{
}
 
/*!
    \internal
*/
QQmlScriptString::QQmlScriptString(const QString &script, QQmlContext *context, QObject *scope)
:  d(new QQmlScriptStringPrivate)
{
    d->script = script;
    d->context = context;
    d->scope = scope;
}
 
/*!
Copies \a other.
*/
QQmlScriptString::QQmlScriptString(const QQmlScriptString &other)
: d(other.d)
{
}
 
/*!
\internal
*/
QQmlScriptString::~QQmlScriptString()
{
}
 
/*!
Assigns \a other to this.
*/
QQmlScriptString &QQmlScriptString::operator=(const QQmlScriptString &other)
{
    d = other.d;
    return *this;
}
 
/*!
Returns \c true if this and the \a other QQmlScriptString objects are equal.
 
\sa operator!=()
*/
bool QQmlScriptString::operator==(const QQmlScriptString &other) const
{
    if (d == other.d)
        return true;
    if (!d || !other.d)
        return false;
 
    if (d->isNumberLiteral || other.d->isNumberLiteral)
        return d->isNumberLiteral && other.d->isNumberLiteral && d->numberValue == other.d->numberValue;
 
    if (d->isStringLiteral || other.d->isStringLiteral)
        return d->isStringLiteral && other.d->isStringLiteral && d->script == other.d->script;
 
    if (d->script == QLatin1String("true") ||
        d->script == QLatin1String("false") ||
        d->script == QLatin1String("undefined") ||
        d->script == QLatin1String("null"))
        return d->script == other.d->script;
 
    return d->context == other.d->context &&
           d->scope == other.d->scope &&
           d->script == other.d->script &&
           d->bindingId == other.d->bindingId;
}
 
/*!
Returns \c true if this and the \a other QQmlScriptString objects are different.
 
\sa operator==()
*/
bool QQmlScriptString::operator!=(const QQmlScriptString &other) const
{
    return !operator==(other);
}
 
/*!
Returns whether the QQmlScriptString is empty.
*/
bool QQmlScriptString::isEmpty() const
{
    if (!d)
        return true;
    if (!d->script.isEmpty())
        return false;
    return d->bindingId == -1;
}
 
/*!
Returns whether the content of the QQmlScriptString is the \c undefined literal.
*/
bool QQmlScriptString::isUndefinedLiteral() const
{
    return d && d->script == QLatin1String("undefined");
}
 
/*!
Returns whether the content of the QQmlScriptString is the \c null literal.
*/
bool QQmlScriptString::isNullLiteral() const
{
    return d && d->script == QLatin1String("null");
}
 
/*!
If the content of the QQmlScriptString is a string literal, returns that string.
Otherwise returns a null QString.
*/
QString QQmlScriptString::stringLiteral() const
{
    if (d && d->isStringLiteral)
        return d->script.mid(1, d->script.size()-2);
    return QString();
}
 
/*!
If the content of the QQmlScriptString is a number literal, returns that number and
sets \a ok to true. Otherwise returns 0.0 and sets \a ok to false.
*/
qreal QQmlScriptString::numberLiteral(bool *ok) const
{
    if (ok)
        *ok = d && d->isNumberLiteral;
    return (d && d->isNumberLiteral) ? d->numberValue : 0.;
}
 
/*!
If the content of the QQmlScriptString is a boolean literal, returns the boolean value and
sets \a ok to true. Otherwise returns false and sets \a ok to false.
*/
bool QQmlScriptString::booleanLiteral(bool *ok) const
{
    bool isTrue = d && d->script == QLatin1String("true");
    bool isFalse = !isTrue && d && d->script == QLatin1String("false");
    if (ok)
        *ok = isTrue || isFalse;
    return isTrue ? true : false;
}
 
QT_END_NAMESPACE
 
#include "moc_qqmlscriptstring.cpp"