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Diffstat (limited to 'src/xmlpatterns/expr/qaxisstep.cpp')
| -rw-r--r-- | src/xmlpatterns/expr/qaxisstep.cpp | 247 |
1 files changed, 247 insertions, 0 deletions
diff --git a/src/xmlpatterns/expr/qaxisstep.cpp b/src/xmlpatterns/expr/qaxisstep.cpp new file mode 100644 index 0000000..5297dab --- /dev/null +++ b/src/xmlpatterns/expr/qaxisstep.cpp @@ -0,0 +1,247 @@ +/**************************************************************************** +** +** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies). +** Contact: Qt Software Information (qt-info@nokia.com) +** +** This file is part of the QtXmlPatterns module of the Qt Toolkit. +** +** $QT_BEGIN_LICENSE:LGPL$ +** No Commercial Usage +** This file contains pre-release code and may not be distributed. +** You may use this file in accordance with the terms and conditions +** contained in the either Technology Preview License Agreement or the +** Beta Release License Agreement. +** +** GNU Lesser General Public License Usage +** Alternatively, 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. +** +** In addition, as a special exception, Nokia gives you certain +** additional rights. These rights are described in the Nokia Qt LGPL +** Exception version 1.0, included in the file LGPL_EXCEPTION.txt in this +** package. +** +** GNU General Public License Usage +** Alternatively, this file may be used under the terms of the GNU +** General Public License version 3.0 as published by the Free Software +** Foundation and appearing in the file LICENSE.GPL included in the +** packaging of this file. Please review the following information to +** ensure the GNU General Public License version 3.0 requirements will be +** met: http://www.gnu.org/copyleft/gpl.html. +** +** If you are unsure which license is appropriate for your use, please +** contact the sales department at qt-sales@nokia.com. +** $QT_END_LICENSE$ +** +****************************************************************************/ + +#include "qbuiltintypes_p.h" +#include "qcommonsequencetypes_p.h" +#include "qitemmappingiterator_p.h" +#include "qgenericsequencetype_p.h" +#include "qparentnodeaxis_p.h" + +#include "qaxisstep_p.h" + +QT_BEGIN_NAMESPACE + +using namespace QPatternist; + +namespace QPatternist +{ + /** + * This operator is needed for the s_whenAxisNodeKindEmpty array. The @c int constructors + * ensure we invoke another operator| such that we don't get an infinite loop. + */ + static inline QXmlNodeModelIndex::NodeKind operator|(const QXmlNodeModelIndex::NodeKind &op1, const QXmlNodeModelIndex::NodeKind &op2) + { + return QXmlNodeModelIndex::NodeKind(int(op1) | int(op2)); + } +} + +/** + * @note The order is significant. It is of the same order as the values in QXmlNodeModelIndex::Axis is declared. + */ +const QXmlNodeModelIndex::NodeKind AxisStep::s_whenAxisNodeKindEmpty[] = +{ + QXmlNodeModelIndex::Attribute|QXmlNodeModelIndex::Text|QXmlNodeModelIndex::ProcessingInstruction|QXmlNodeModelIndex::Comment|QXmlNodeModelIndex::Namespace, // child; + QXmlNodeModelIndex::Attribute|QXmlNodeModelIndex::Text|QXmlNodeModelIndex::ProcessingInstruction|QXmlNodeModelIndex::Comment|QXmlNodeModelIndex::Namespace, // descendant; + QXmlNodeModelIndex::Document|QXmlNodeModelIndex::Attribute|QXmlNodeModelIndex::Text|QXmlNodeModelIndex::ProcessingInstruction|QXmlNodeModelIndex::Comment|QXmlNodeModelIndex::Namespace,// attribute; + QXmlNodeModelIndex::NodeKind(0), // self; + QXmlNodeModelIndex::NodeKind(0), // descendant-or-self; + QXmlNodeModelIndex::Document|QXmlNodeModelIndex::Attribute|QXmlNodeModelIndex::Text|QXmlNodeModelIndex::ProcessingInstruction|QXmlNodeModelIndex::Comment|QXmlNodeModelIndex::Namespace, // namespace; + QXmlNodeModelIndex::Document, // following; + QXmlNodeModelIndex::Document, // parent; + QXmlNodeModelIndex::Document, // ancestor + QXmlNodeModelIndex::Document|QXmlNodeModelIndex::Attribute|QXmlNodeModelIndex::Namespace, // preceding-sibling; + QXmlNodeModelIndex::Document|QXmlNodeModelIndex::Attribute|QXmlNodeModelIndex::Namespace, // following-sibling; + QXmlNodeModelIndex::Document, // preceding; + QXmlNodeModelIndex::NodeKind(0) // ancestor-or-self; +}; + +bool AxisStep::isAlwaysEmpty(const QXmlNodeModelIndex::Axis axis, const QXmlNodeModelIndex::NodeKind nodeKind) +{ + return (s_whenAxisNodeKindEmpty[(1 >> axis) - 1] & nodeKind) != 0; +} + +AxisStep::AxisStep(const QXmlNodeModelIndex::Axis a, + const ItemType::Ptr &nt) : m_axis(a), + m_nodeTest(nt) +{ + Q_ASSERT(m_nodeTest); + Q_ASSERT_X(BuiltinTypes::node->xdtTypeMatches(m_nodeTest), Q_FUNC_INFO, + "We assume we're a node type."); +} + +Item AxisStep::mapToItem(const QXmlNodeModelIndex &node, + const DynamicContext::Ptr &context) const +{ + Q_ASSERT(!node.isNull()); + Q_ASSERT(Item(node).isNode()); + Q_ASSERT(Item(node)); + Q_UNUSED(context); + + if(m_nodeTest->itemMatches(Item(node))) + return Item(node); + else + return Item(); +} + +Item::Iterator::Ptr AxisStep::evaluateSequence(const DynamicContext::Ptr &context) const +{ + /* If we don't have a focus, it's either a bug or our parent isn't a Path + * that have advanced the focus iterator. Hence, attempt to advance the focus on our own. */ + if(!context->contextItem()) + context->focusIterator()->next(); + + Q_ASSERT(context->contextItem()); + + const QXmlNodeModelIndex::Iterator::Ptr source(context->contextItem().asNode().iterate(m_axis)); + + return makeItemMappingIterator<Item>(ConstPtr(this), source, context); +} + +Item AxisStep::evaluateSingleton(const DynamicContext::Ptr &context) const +{ + /* If we don't have a focus, it's either a bug or our parent isn't a Path + * that have advanced the focus iterator. Hence, attempt to advance the focus on our own. */ + if(!context->contextItem()) + context->focusIterator()->next(); + + Q_ASSERT(context->contextItem()); + + const QXmlNodeModelIndex::Iterator::Ptr it(context->contextItem().asNode().iterate(m_axis)); + QXmlNodeModelIndex next(it->next()); + + while(!next.isNull()) + { + const Item candidate(mapToItem(next, context)); + + if(candidate) + return candidate; + else + next = it->next(); + }; + + return Item(); +} + +Expression::Ptr AxisStep::typeCheck(const StaticContext::Ptr &context, + const SequenceType::Ptr &reqType) +{ + if(m_axis == QXmlNodeModelIndex::AxisParent && *m_nodeTest == *BuiltinTypes::node) + { + /* We only rewrite parent::node() to ParentNodeAxis. */ + return rewrite(Expression::Ptr(new ParentNodeAxis()), context)->typeCheck(context, reqType); + } + /* TODO temporarily disabled + else if(isAlwaysEmpty(m_axis, static_cast<const AnyNodeType *>(m_nodeTest.data())->nodeKind())) + return EmptySequence::create(this, context); + */ + else + return EmptyContainer::typeCheck(context, reqType); +} + +SequenceType::Ptr AxisStep::staticType() const +{ + Cardinality cardinality; + + if(m_axis == QXmlNodeModelIndex::AxisSelf || m_axis == QXmlNodeModelIndex::AxisParent) + cardinality = Cardinality::zeroOrOne(); + else + cardinality = Cardinality::zeroOrMore(); + + return makeGenericSequenceType(m_nodeTest, + cardinality); +} + +SequenceType::List AxisStep::expectedOperandTypes() const +{ + SequenceType::List result; + result.append(CommonSequenceTypes::ZeroOrMoreNodes); + return result; +} + +Expression::Properties AxisStep::properties() const +{ + return RequiresContextItem | DisableElimination; +} + +ItemType::Ptr AxisStep::expectedContextItemType() const +{ + return BuiltinTypes::node; +} + +ExpressionVisitorResult::Ptr AxisStep::accept(const ExpressionVisitor::Ptr &visitor) const +{ + return visitor->visit(this); +} + +QXmlNodeModelIndex::Axis AxisStep::axis() const +{ + return m_axis; +} + +QString AxisStep::axisName(const QXmlNodeModelIndex::Axis axis) +{ + const char *result = 0; + + switch(axis) + { + /* These must not be translated. */ + case QXmlNodeModelIndex::AxisAncestorOrSelf: result = "ancestor-or-self"; break; + case QXmlNodeModelIndex::AxisAncestor: result = "ancestor"; break; + case QXmlNodeModelIndex::AxisAttributeOrTop: result = "attribute-or-top"; break; + case QXmlNodeModelIndex::AxisAttribute: result = "attribute"; break; + case QXmlNodeModelIndex::AxisChildOrTop: result = "child-or-top"; break; + case QXmlNodeModelIndex::AxisChild: result = "child"; break; + case QXmlNodeModelIndex::AxisDescendantOrSelf: result = "descendant-or-self"; break; + case QXmlNodeModelIndex::AxisDescendant: result = "descendant"; break; + case QXmlNodeModelIndex::AxisFollowing: result = "following"; break; + case QXmlNodeModelIndex::AxisFollowingSibling: result = "following-sibling"; break; + case QXmlNodeModelIndex::AxisNamespace: result = "namespace"; break; + case QXmlNodeModelIndex::AxisParent: result = "parent"; break; + case QXmlNodeModelIndex::AxisPreceding: result = "preceding"; break; + case QXmlNodeModelIndex::AxisPrecedingSibling: result = "preceding-sibling"; break; + case QXmlNodeModelIndex::AxisSelf: result = "self"; break; + } + + Q_ASSERT_X(result, Q_FUNC_INFO, "An unknown axis type was apparently encountered."); + return QString::fromLatin1(result); +} + +PatternPriority AxisStep::patternPriority() const +{ + return static_cast<const AnyNodeType *>(m_nodeTest.data())->patternPriority(); +} + +Expression::ID AxisStep::id() const +{ + return IDAxisStep; +} + +QT_END_NAMESPACE |