Windows-4.7.4/src/script/api/qscriptvalueiterator.cpp - platform/external/qt - Git at Google

 /****************************************************************************
 **
 ** Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies).
 ** All rights reserved.
 ** Contact: Nokia Corporation (qt-info@nokia.com)
 **
 ** This file is part of the QtScript module of the Qt Toolkit.
 **
 ** $QT_BEGIN_LICENSE:LGPL-ONLY$
 ** GNU Lesser General Public License Usage
 ** This file may be used under the terms of the GNU Lesser
 ** General Public License version 2.1 as published by the Free Software
 ** Foundation and appearing in the file LICENSE.LGPL included in the
 ** packaging of this file.  Please review the following information to
 ** ensure the GNU Lesser General Public License version 2.1 requirements
 ** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
 **
 ** If you have questions regarding the use of this file, please contact
 ** Nokia at qt-info@nokia.com.
 ** $QT_END_LICENSE$
 **
 ****************************************************************************/

 #include "config.h"
 #include "qscriptvalueiterator.h"

 #include "qscriptstring.h"
 #include "qscriptengine.h"
 #include "qscriptengine_p.h"
 #include "qscriptvalue_p.h"
 #include "qlinkedlist.h"


 #include "JSObject.h"
 #include "PropertyNameArray.h"
 #include "JSArray.h"
 #include "JSFunction.h"

 QT_BEGIN_NAMESPACE

 /*!
   \since 4.3
   \class QScriptValueIterator

   \brief The QScriptValueIterator class provides a Java-style iterator for QScriptValue.

   \ingroup script


   The QScriptValueIterator constructor takes a QScriptValue as
   argument.  After construction, the iterator is located at the very
   beginning of the sequence of properties. Here's how to iterate over
   all the properties of a QScriptValue:

   \snippet doc/src/snippets/code/src_script_qscriptvalueiterator.cpp 0

   The next() advances the iterator. The name(), value() and flags()
   functions return the name, value and flags of the last item that was
   jumped over.

   If you want to remove properties as you iterate over the
   QScriptValue, use remove(). If you want to modify the value of a
   property, use setValue().

   Note that QScriptValueIterator only iterates over the QScriptValue's
   own properties; i.e. it does not follow the prototype chain. You can
   use a loop like this to follow the prototype chain:

   \snippet doc/src/snippets/code/src_script_qscriptvalueiterator.cpp 1

   Note that QScriptValueIterator will not automatically skip over
   properties that have the QScriptValue::SkipInEnumeration flag set;
   that flag only affects iteration in script code.  If you want, you
   can skip over such properties with code like the following:

   \snippet doc/src/snippets/code/src_script_qscriptvalueiterator.cpp 2

   \sa QScriptValue::property()
 */

 class QScriptValueIteratorPrivate
 {
 public:
     QScriptValueIteratorPrivate()
         : initialized(false)
     {}

     ~QScriptValueIteratorPrivate()
     {
         if (!initialized)
             return;
         QScriptEnginePrivate *eng_p = engine();
         if (!eng_p)
             return;
         QScript::APIShim shim(eng_p);
         propertyNames.clear(); //destroying the identifiers need to be done under the APIShim guard
     }

     QScriptValuePrivate *object() const
     {
         return QScriptValuePrivate::get(objectValue);
     }

     QScriptEnginePrivate *engine() const
     {
         return QScriptEnginePrivate::get(objectValue.engine());
     }

     void ensureInitialized()
     {
         if (initialized)
             return;
         QScriptEnginePrivate *eng_p = engine();
         QScript::APIShim shim(eng_p);
         JSC::ExecState *exec = eng_p->globalExec();
         JSC::PropertyNameArray propertyNamesArray(exec);
         JSC::asObject(object()->jscValue)->getOwnPropertyNames(exec, propertyNamesArray, JSC::IncludeDontEnumProperties);

         JSC::PropertyNameArray::const_iterator propertyNamesIt = propertyNamesArray.begin();
         for(; propertyNamesIt != propertyNamesArray.end(); ++propertyNamesIt) {
             propertyNames.append(*propertyNamesIt);
         }
         it = propertyNames.begin();
         initialized = true;
     }

     QScriptValue objectValue;
     QLinkedList<JSC::Identifier> propertyNames;
     QLinkedList<JSC::Identifier>::iterator it;
     QLinkedList<JSC::Identifier>::iterator current;
     bool initialized;
 };

 /*!
   Constructs an iterator for traversing \a object. The iterator is
   set to be at the front of the sequence of properties (before the
   first property).
 */
 QScriptValueIterator::QScriptValueIterator(const QScriptValue &object)
     : d_ptr(0)
 {
     if (object.isObject()) {
         d_ptr.reset(new QScriptValueIteratorPrivate());
         d_ptr->objectValue = object;
     }
 }

 /*!
   Destroys the iterator.
 */
 QScriptValueIterator::~QScriptValueIterator()
 {
 }

 /*!
   Returns true if there is at least one item ahead of the iterator
   (i.e. the iterator is \e not at the back of the property sequence);
   otherwise returns false.

   \sa next(), hasPrevious()
 */
 bool QScriptValueIterator::hasNext() const
 {
     Q_D(const QScriptValueIterator);
     if (!d)
         return false;

     const_cast<QScriptValueIteratorPrivate*>(d)->ensureInitialized();
     return d->it != d->propertyNames.end();
 }

 /*!
   Advances the iterator by one position.

   Calling this function on an iterator located at the back of the
   container leads to undefined results.

   \sa hasNext(), previous(), name()
 */
 void QScriptValueIterator::next()
 {
     Q_D(QScriptValueIterator);
     if (!d)
         return;
     d->ensureInitialized();

     d->current = d->it;
     ++(d->it);
 }

 /*!
   Returns true if there is at least one item behind the iterator
   (i.e. the iterator is \e not at the front of the property sequence);
   otherwise returns false.

   \sa previous(), hasNext()
 */
 bool QScriptValueIterator::hasPrevious() const
 {
     Q_D(const QScriptValueIterator);
     if (!d)
         return false;

     const_cast<QScriptValueIteratorPrivate*>(d)->ensureInitialized();
     return d->it != d->propertyNames.begin();
 }

 /*!
   Moves the iterator back by one position.

   Calling this function on an iterator located at the front of the
   container leads to undefined results.

   \sa hasPrevious(), next(), name()
 */
 void QScriptValueIterator::previous()
 {
     Q_D(QScriptValueIterator);
     if (!d)
         return;
     d->ensureInitialized();
     --(d->it);
     d->current = d->it;
 }

 /*!
   Moves the iterator to the front of the QScriptValue (before the
   first property).

   \sa toBack(), next()
 */
 void QScriptValueIterator::toFront()
 {
     Q_D(QScriptValueIterator);
     if (!d)
         return;
     d->ensureInitialized();
     d->it = d->propertyNames.begin();
 }

 /*!
   Moves the iterator to the back of the QScriptValue (after the
   last property).

   \sa toFront(), previous()
 */
 void QScriptValueIterator::toBack()
 {
     Q_D(QScriptValueIterator);
     if (!d)
         return;
     d->ensureInitialized();
     d->it = d->propertyNames.end();
 }

 /*!
   Returns the name of the last property that was jumped over using
   next() or previous().

   \sa value(), flags()
 */
 QString QScriptValueIterator::name() const
 {
     Q_D(const QScriptValueIterator);
     if (!d || !d->initialized || !d->engine())
         return QString();
     return d->current->ustring();
 }

 /*!
   \since 4.4

   Returns the name of the last property that was jumped over using
   next() or previous().
 */
 QScriptString QScriptValueIterator::scriptName() const
 {
     Q_D(const QScriptValueIterator);
     if (!d || !d->initialized || !d->engine())
         return QScriptString();
     return d->engine()->toStringHandle(*d->current);
 }

 /*!
   Returns the value of the last property that was jumped over using
   next() or previous().

   \sa setValue(), name()
 */
 QScriptValue QScriptValueIterator::value() const
 {
     Q_D(const QScriptValueIterator);
     if (!d || !d->initialized || !d->engine())
         return QScriptValue();
     QScript::APIShim shim(d->engine());
     JSC::JSValue jsValue = d->object()->property(*d->current);
     return d->engine()->scriptValueFromJSCValue(jsValue);
 }

 /*!
   Sets the \a value of the last property that was jumped over using
   next() or previous().

   \sa value(), name()
 */
 void QScriptValueIterator::setValue(const QScriptValue &value)
 {
     Q_D(QScriptValueIterator);
     if (!d || !d->initialized || !d->engine())
         return;
     QScript::APIShim shim(d->engine());
     JSC::JSValue jsValue = d->engine()->scriptValueToJSCValue(value);
     d->object()->setProperty(*d->current, jsValue);
 }

 /*!
   Returns the flags of the last property that was jumped over using
   next() or previous().

   \sa value()
 */
 QScriptValue::PropertyFlags QScriptValueIterator::flags() const
 {
     Q_D(const QScriptValueIterator);
     if (!d || !d->initialized || !d->engine())
         return 0;
     QScript::APIShim shim(d->engine());
     return d->object()->propertyFlags(*d->current);
 }

 /*!
   Removes the last property that was jumped over using next()
   or previous().

   \sa setValue()
 */
 void QScriptValueIterator::remove()
 {
     Q_D(QScriptValueIterator);
     if (!d || !d->initialized || !d->engine())
         return;
     QScript::APIShim shim(d->engine());
     d->object()->setProperty(*d->current, JSC::JSValue());
     d->propertyNames.erase(d->current);
 }

 /*!
   Makes the iterator operate on \a object. The iterator is set to be
   at the front of the sequence of properties (before the first
   property).
 */
 QScriptValueIterator& QScriptValueIterator::operator=(QScriptValue &object)
 {
     d_ptr.reset();
     if (object.isObject()) {
         d_ptr.reset(new QScriptValueIteratorPrivate());
         d_ptr->objectValue = object;
     }
     return *this;
 }

 QT_END_NAMESPACE
	/****************************************************************************
	**
	** Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies).
	** All rights reserved.
	** Contact: Nokia Corporation (qt-info@nokia.com)
	**
	** This file is part of the QtScript module of the Qt Toolkit.
	**
	** $QT_BEGIN_LICENSE:LGPL-ONLY$
	** GNU Lesser General Public License Usage
	** This file may be used under the terms of the GNU Lesser
	** General Public License version 2.1 as published by the Free Software
	** Foundation and appearing in the file LICENSE.LGPL included in the
	** packaging of this file. Please review the following information to
	** ensure the GNU Lesser General Public License version 2.1 requirements
	** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
	**
	** If you have questions regarding the use of this file, please contact
	** Nokia at qt-info@nokia.com.
	** $QT_END_LICENSE$
	**
	****************************************************************************/

	#include "config.h"
	#include "qscriptvalueiterator.h"

	#include "qscriptstring.h"
	#include "qscriptengine.h"
	#include "qscriptengine_p.h"
	#include "qscriptvalue_p.h"
	#include "qlinkedlist.h"


	#include "JSObject.h"
	#include "PropertyNameArray.h"
	#include "JSArray.h"
	#include "JSFunction.h"

	QT_BEGIN_NAMESPACE

	/*!
	\since 4.3
	\class QScriptValueIterator

	\brief The QScriptValueIterator class provides a Java-style iterator for QScriptValue.

	\ingroup script


	The QScriptValueIterator constructor takes a QScriptValue as
	argument. After construction, the iterator is located at the very
	beginning of the sequence of properties. Here's how to iterate over
	all the properties of a QScriptValue:

	\snippet doc/src/snippets/code/src_script_qscriptvalueiterator.cpp 0

	The next() advances the iterator. The name(), value() and flags()
	functions return the name, value and flags of the last item that was
	jumped over.

	If you want to remove properties as you iterate over the
	QScriptValue, use remove(). If you want to modify the value of a
	property, use setValue().

	Note that QScriptValueIterator only iterates over the QScriptValue's
	own properties; i.e. it does not follow the prototype chain. You can
	use a loop like this to follow the prototype chain:

	\snippet doc/src/snippets/code/src_script_qscriptvalueiterator.cpp 1

	Note that QScriptValueIterator will not automatically skip over
	properties that have the QScriptValue::SkipInEnumeration flag set;
	that flag only affects iteration in script code. If you want, you
	can skip over such properties with code like the following:

	\snippet doc/src/snippets/code/src_script_qscriptvalueiterator.cpp 2

	\sa QScriptValue::property()
	*/

	class QScriptValueIteratorPrivate
	{
	public:
	QScriptValueIteratorPrivate()
	: initialized(false)
	{}

	~QScriptValueIteratorPrivate()
	{
	if (!initialized)
	return;
	QScriptEnginePrivate *eng_p = engine();
	if (!eng_p)
	return;
	QScript::APIShim shim(eng_p);
	propertyNames.clear(); //destroying the identifiers need to be done under the APIShim guard
	}

	QScriptValuePrivate *object() const
	{
	return QScriptValuePrivate::get(objectValue);
	}

	QScriptEnginePrivate *engine() const
	{
	return QScriptEnginePrivate::get(objectValue.engine());
	}

	void ensureInitialized()
	{
	if (initialized)
	return;
	QScriptEnginePrivate *eng_p = engine();
	QScript::APIShim shim(eng_p);
	JSC::ExecState *exec = eng_p->globalExec();
	JSC::PropertyNameArray propertyNamesArray(exec);
	JSC::asObject(object()->jscValue)->getOwnPropertyNames(exec, propertyNamesArray, JSC::IncludeDontEnumProperties);

	JSC::PropertyNameArray::const_iterator propertyNamesIt = propertyNamesArray.begin();
	for(; propertyNamesIt != propertyNamesArray.end(); ++propertyNamesIt) {
	propertyNames.append(*propertyNamesIt);
	}
	it = propertyNames.begin();
	initialized = true;
	}

	QScriptValue objectValue;
	QLinkedList<JSC::Identifier> propertyNames;
	QLinkedList<JSC::Identifier>::iterator it;
	QLinkedList<JSC::Identifier>::iterator current;
	bool initialized;
	};

	/*!
	Constructs an iterator for traversing \a object. The iterator is
	set to be at the front of the sequence of properties (before the
	first property).
	*/
	QScriptValueIterator::QScriptValueIterator(const QScriptValue &object)
	: d_ptr(0)
	{
	if (object.isObject()) {
	d_ptr.reset(new QScriptValueIteratorPrivate());
	d_ptr->objectValue = object;
	}
	}

	/*!
	Destroys the iterator.
	*/
	QScriptValueIterator::~QScriptValueIterator()
	{
	}

	/*!
	Returns true if there is at least one item ahead of the iterator
	(i.e. the iterator is \e not at the back of the property sequence);
	otherwise returns false.

	\sa next(), hasPrevious()
	*/
	bool QScriptValueIterator::hasNext() const
	{
	Q_D(const QScriptValueIterator);
	if (!d)
	return false;

	const_cast<QScriptValueIteratorPrivate*>(d)->ensureInitialized();
	return d->it != d->propertyNames.end();
	}

	/*!
	Advances the iterator by one position.

	Calling this function on an iterator located at the back of the
	container leads to undefined results.

	\sa hasNext(), previous(), name()
	*/
	void QScriptValueIterator::next()
	{
	Q_D(QScriptValueIterator);
	if (!d)
	return;
	d->ensureInitialized();

	d->current = d->it;
	++(d->it);
	}

	/*!
	Returns true if there is at least one item behind the iterator
	(i.e. the iterator is \e not at the front of the property sequence);
	otherwise returns false.

	\sa previous(), hasNext()
	*/
	bool QScriptValueIterator::hasPrevious() const
	{
	Q_D(const QScriptValueIterator);
	if (!d)
	return false;

	const_cast<QScriptValueIteratorPrivate*>(d)->ensureInitialized();
	return d->it != d->propertyNames.begin();
	}

	/*!
	Moves the iterator back by one position.

	Calling this function on an iterator located at the front of the
	container leads to undefined results.

	\sa hasPrevious(), next(), name()
	*/
	void QScriptValueIterator::previous()
	{
	Q_D(QScriptValueIterator);
	if (!d)
	return;
	d->ensureInitialized();
	--(d->it);
	d->current = d->it;
	}

	/*!
	Moves the iterator to the front of the QScriptValue (before the
	first property).

	\sa toBack(), next()
	*/
	void QScriptValueIterator::toFront()
	{
	Q_D(QScriptValueIterator);
	if (!d)
	return;
	d->ensureInitialized();
	d->it = d->propertyNames.begin();
	}

	/*!
	Moves the iterator to the back of the QScriptValue (after the
	last property).

	\sa toFront(), previous()
	*/
	void QScriptValueIterator::toBack()
	{
	Q_D(QScriptValueIterator);
	if (!d)
	return;
	d->ensureInitialized();
	d->it = d->propertyNames.end();
	}

	/*!
	Returns the name of the last property that was jumped over using
	next() or previous().

	\sa value(), flags()
	*/
	QString QScriptValueIterator::name() const
	{
	Q_D(const QScriptValueIterator);
	if (!d \|\| !d->initialized \|\| !d->engine())
	return QString();
	return d->current->ustring();
	}

	/*!
	\since 4.4

	Returns the name of the last property that was jumped over using
	next() or previous().
	*/
	QScriptString QScriptValueIterator::scriptName() const
	{
	Q_D(const QScriptValueIterator);
	if (!d \|\| !d->initialized \|\| !d->engine())
	return QScriptString();
	return d->engine()->toStringHandle(*d->current);
	}

	/*!
	Returns the value of the last property that was jumped over using
	next() or previous().

	\sa setValue(), name()
	*/
	QScriptValue QScriptValueIterator::value() const
	{
	Q_D(const QScriptValueIterator);
	if (!d \|\| !d->initialized \|\| !d->engine())
	return QScriptValue();
	QScript::APIShim shim(d->engine());
	JSC::JSValue jsValue = d->object()->property(*d->current);
	return d->engine()->scriptValueFromJSCValue(jsValue);
	}

	/*!
	Sets the \a value of the last property that was jumped over using
	next() or previous().

	\sa value(), name()
	*/
	void QScriptValueIterator::setValue(const QScriptValue &value)
	{
	Q_D(QScriptValueIterator);
	if (!d \|\| !d->initialized \|\| !d->engine())
	return;
	QScript::APIShim shim(d->engine());
	JSC::JSValue jsValue = d->engine()->scriptValueToJSCValue(value);
	d->object()->setProperty(*d->current, jsValue);
	}

	/*!
	Returns the flags of the last property that was jumped over using
	next() or previous().

	\sa value()
	*/
	QScriptValue::PropertyFlags QScriptValueIterator::flags() const
	{
	Q_D(const QScriptValueIterator);
	if (!d \|\| !d->initialized \|\| !d->engine())
	return 0;
	QScript::APIShim shim(d->engine());
	return d->object()->propertyFlags(*d->current);
	}

	/*!
	Removes the last property that was jumped over using next()
	or previous().

	\sa setValue()
	*/
	void QScriptValueIterator::remove()
	{
	Q_D(QScriptValueIterator);
	if (!d \|\| !d->initialized \|\| !d->engine())
	return;
	QScript::APIShim shim(d->engine());
	d->object()->setProperty(*d->current, JSC::JSValue());
	d->propertyNames.erase(d->current);
	}

	/*!
	Makes the iterator operate on \a object. The iterator is set to be
	at the front of the sequence of properties (before the first
	property).
	*/
	QScriptValueIterator& QScriptValueIterator::operator=(QScriptValue &object)
	{
	d_ptr.reset();
	if (object.isObject()) {
	d_ptr.reset(new QScriptValueIteratorPrivate());
	d_ptr->objectValue = object;
	}
	return *this;
	}

	QT_END_NAMESPACE