--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/src/xmlpatterns/expr/qpath.cpp Mon Jan 11 14:00:40 2010 +0000
@@ -0,0 +1,271 @@
+/****************************************************************************
+**
+** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (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 Technology Preview License Agreement accompanying
+** this package.
+**
+** 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 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** If you have questions regarding the use of this file, please contact
+** Nokia at qt-info@nokia.com.
+**
+**
+**
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "qbuiltintypes_p.h"
+#include "qcommonsequencetypes_p.h"
+#include "qgenericsequencetype_p.h"
+#include "qnodesort_p.h"
+#include "qpatternistlocale_p.h"
+#include "qsequencemappingiterator_p.h"
+#include "qtypechecker_p.h"
+
+#include "qpath_p.h"
+
+QT_BEGIN_NAMESPACE
+
+using namespace QPatternist;
+
+Path::Path(const Expression::Ptr &operand1,
+ const Expression::Ptr &operand2,
+ const Kind kind) : PairContainer(operand1, operand2)
+ , m_hasCreatedSorter(kind != RegularPath)
+ , m_isLast(false)
+ , m_checkXPTY0018(kind == RegularPath)
+ , m_kind(kind)
+{
+}
+
+Item::Iterator::Ptr Path::mapToSequence(const Item &item,
+ const DynamicContext::Ptr &context) const
+{
+ /* item is the focus here. That is in <e/>/1, item is <e/>. However,
+ * we don't use it, since the context item is accessed through
+ * DynamicContext::focusIterator() and friends. */
+ Q_ASSERT(item);
+ Q_UNUSED(item); /* Needed when compiling in release mode. */
+ return m_operand2->evaluateSequence(context);
+}
+
+Item::Iterator::Ptr Path::evaluateSequence(const DynamicContext::Ptr &context) const
+{
+ /* Note, we use the old context for m_operand1. */
+ const Item::Iterator::Ptr source(m_operand1->evaluateSequence(context));
+
+ const DynamicContext::Ptr focus(context->createFocus());
+ focus->setFocusIterator(source);
+
+ const Item::Iterator::Ptr result(makeSequenceMappingIterator<Item>(ConstPtr(this), source, focus));
+
+ if(m_checkXPTY0018)
+ {
+ /* This is an expensive code path, but it should happen very rarely. */
+
+ enum FoundItem
+ {
+ FoundNone,
+ FoundNode,
+ FoundAtomicValue
+ } hasFound = FoundNone;
+
+ Item::List whenChecked;
+
+ Item next(result->next());
+
+ while(next)
+ {
+ const FoundItem found = next.isAtomicValue() ? FoundAtomicValue : FoundNode;
+
+ if(hasFound != FoundNone && hasFound != found)
+ {
+ /* It's an atomic value and we've already found a node. Mixed content. */
+ context->error(QtXmlPatterns::tr("The last step in a path must contain either nodes "
+ "or atomic values. It cannot be a mixture between the two."),
+ ReportContext::XPTY0018, this);
+ }
+ else
+ hasFound = found;
+
+ whenChecked.append(next);
+ next = result->next();
+ }
+
+ return makeListIterator(whenChecked);
+ }
+ else
+ return result;
+}
+
+Item Path::evaluateSingleton(const DynamicContext::Ptr &context) const
+{
+ /* This function is called if both operands' cardinality is exactly-one. Therefore
+ * we manually go forward in the focus by calling next().
+ *
+ * We don't check for XPTY0018, only in evaluateSequence(), since if we're guaranteed
+ * to evaluate to one item, we can only evaluate to one node or one atomic value.
+ */
+
+ /* Note, we use the old context for m_operand1. */
+ const Item::Iterator::Ptr source(m_operand1->evaluateSequence(context));
+
+ const DynamicContext::Ptr focus(context->createFocus());
+ focus->setFocusIterator(source);
+
+ /* This test is needed because if the focus is empty, we don't want to(nor can't) evaluate
+ * the next step. */
+ // TODO Why are we at all invoked then?
+ if(source->next())
+ return m_operand2->evaluateSingleton(focus);
+ else
+ return Item();
+}
+
+void Path::evaluateToSequenceReceiver(const DynamicContext::Ptr &context) const
+{
+ /* Note, we use the old context for m_operand1. */
+ const Item::Iterator::Ptr source(m_operand1->evaluateSequence(context));
+
+ const DynamicContext::Ptr focus(context->createFocus());
+ focus->setFocusIterator(source);
+
+ while(source->next())
+ m_operand2->evaluateToSequenceReceiver(focus);
+}
+
+Expression::Ptr Path::compress(const StaticContext::Ptr &context)
+{
+ const Expression::Ptr me(PairContainer::compress(context));
+
+ /* "./expr" is by now equal to "expr" since we've done
+ * focus/type checks, and a node sorter has been inserted. */
+ if(m_operand1->is(IDContextItem))
+ return m_operand2;
+
+ /* We do this as late as we can, such that we pick up the most recent type
+ * from the operand. */
+ if(m_isLast && m_kind != XSLTForEach && m_operand2->staticType()->itemType() == BuiltinTypes::item)
+ m_checkXPTY0018 = true;
+
+ return me;
+}
+
+Expression::Ptr Path::typeCheck(const StaticContext::Ptr &context,
+ const SequenceType::Ptr &reqType)
+{
+ m_operand2->announceFocusType(newFocusType());
+
+ /* Here we apply the function conversion first, and with the error code
+ * that we want -- XPTY0019 instead of XPTY0004. Unfortunately
+ * PairContainer::typeCheck() will do the type check again, which is
+ * redundant in the case of when we're not XSLTForEach.
+ *
+ * If we're XSLTForEach, it means we're a synthetic "map" expression for
+ * implementing various XSL-T expressions, and hence don't have the
+ * constraint of XPTY0019.
+ *
+ * It's important that typeCheck() is run for the operands(of course), and the call to
+ * PairContainer::typeCheck() ensures that below, in the case that we're XSL-T code.
+ *
+ * The type we expect, CommonSequenceTypes::ZeroOrMoreNodes() needs to be in sync with
+ * what we return in expectedOperandTypes(). */
+ if(m_kind != XSLTForEach)
+ {
+ m_operand1 = TypeChecker::applyFunctionConversion(m_operand1,
+ CommonSequenceTypes::ZeroOrMoreNodes,
+ context,
+ m_kind == ForApplyTemplate ? ReportContext::XTTE0520
+ : ReportContext::XPTY0019);
+ }
+
+ /* If our step ends with atomic values, we cannot sort.
+ *
+ * We must smack the NodeSortExpression ontop before calling typeCheck(), since the latter
+ * may insert an Atomizer, as possibly mandated by reqType. By doing it after, the Atomizer
+ * will be a parent to NodeSortExpression, as opposed to a child.
+ */
+ if(!m_hasCreatedSorter)
+ {
+ m_hasCreatedSorter = true;
+
+ return NodeSortExpression::wrapAround(Expression::Ptr(this), context)->typeCheck(context, reqType);
+ }
+ else
+ return PairContainer::typeCheck(context, reqType);
+}
+
+SequenceType::List Path::expectedOperandTypes() const
+{
+ SequenceType::List result;
+
+ /* This value needs to be in sync with what we pass to
+ * applyFunctionConversion() in typeCheck() above.
+ *
+ * We don't have the XPTY0019 restriction when we're synthetic XSL-T code.
+ */
+ if(m_kind == XSLTForEach)
+ result.append(CommonSequenceTypes::ZeroOrMoreItems);
+ else
+ result.append(CommonSequenceTypes::ZeroOrMoreNodes);
+
+ result.append(CommonSequenceTypes::ZeroOrMoreItems);
+ return result;
+}
+
+SequenceType::Ptr Path::staticType() const
+{
+ const SequenceType::Ptr opType(m_operand2->staticType());
+
+ /* For each parent step, we evaluate the child step. So multiply the two
+ * cardinalities. */
+ return makeGenericSequenceType(opType->itemType(),
+ m_operand1->staticType()->cardinality() * opType->cardinality());
+}
+
+ExpressionVisitorResult::Ptr Path::accept(const ExpressionVisitor::Ptr &visitor) const
+{
+ return visitor->visit(this);
+}
+
+Expression::Properties Path::properties() const
+{
+ return CreatesFocusForLast | ((m_operand1->properties() | m_operand2->properties()) & (RequiresCurrentItem | DisableElimination));
+}
+
+ItemType::Ptr Path::newFocusType() const
+{
+ return m_operand1->staticType()->itemType();
+}
+
+Expression::ID Path::id() const
+{
+ return IDPath;
+}
+
+QT_END_NAMESPACE