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41
42 #include "qcommonsequencetypes_p.h"
43 #include "qcommonvalues_p.h"
44 #include "qemptysequence_p.h"
45 #include "qinteger_p.h"
46 #include "qschemanumeric_p.h"
47 #include "qrangeiterator_p.h"
48
49 #include "qnodecomparison_p.h"
50
51 QT_BEGIN_NAMESPACE
52
53 using namespace QPatternist;
54
NodeComparison(const Expression::Ptr & operand1,const QXmlNodeModelIndex::DocumentOrder op,const Expression::Ptr & operand2)55 NodeComparison::NodeComparison(const Expression::Ptr &operand1,
56 const QXmlNodeModelIndex::DocumentOrder op,
57 const Expression::Ptr &operand2)
58 : PairContainer(operand1, operand2)
59 , m_op(op)
60 {
61 Q_ASSERT(op == QXmlNodeModelIndex::Precedes ||
62 op == QXmlNodeModelIndex::Follows ||
63 op == QXmlNodeModelIndex::Is);
64 }
65
evaluateSingleton(const DynamicContext::Ptr & context) const66 Item NodeComparison::evaluateSingleton(const DynamicContext::Ptr &context) const
67 {
68 switch(evaluate(context))
69 {
70 case True:
71 return CommonValues::BooleanTrue;
72 case False:
73 return CommonValues::BooleanFalse;
74 default:
75 return Item();
76 }
77 }
78
evaluateEBV(const DynamicContext::Ptr & context) const79 bool NodeComparison::evaluateEBV(const DynamicContext::Ptr &context) const
80 {
81 switch(evaluate(context))
82 {
83 case True:
84 return true;
85 default:
86 /* We include the empty sequence here. */
87 return false;
88 }
89 }
90
evaluate(const DynamicContext::Ptr & context) const91 NodeComparison::Result NodeComparison::evaluate(const DynamicContext::Ptr &context) const
92 {
93 const Item op1(m_operand1->evaluateSingleton(context));
94 if(!op1)
95 return Empty;
96
97 const Item op2(m_operand2->evaluateSingleton(context));
98 if(!op2)
99 return Empty;
100
101 /* We just returns an arbitrary value, since there's no order defined for nodes from different
102 * models, except for that the return value must be stable. */
103 if(op1.asNode().model() != op2.asNode().model())
104 return False;
105
106 switch(m_op)
107 {
108 case QXmlNodeModelIndex::Is:
109 return op1.asNode().is(op2.asNode()) ? True : False;
110 case QXmlNodeModelIndex::Precedes:
111 return op1.asNode().compareOrder(op2.asNode()) == QXmlNodeModelIndex::Precedes ? True : False;
112 default:
113 {
114 Q_ASSERT(m_op == QXmlNodeModelIndex::Follows);
115 return op1.asNode().compareOrder(op2.asNode()) == QXmlNodeModelIndex::Follows ? True : False;
116 }
117 }
118 }
119
120
expectedOperandTypes() const121 SequenceType::List NodeComparison::expectedOperandTypes() const
122 {
123 SequenceType::List result;
124 result.append(CommonSequenceTypes::ZeroOrOneNode);
125 result.append(CommonSequenceTypes::ZeroOrOneNode);
126 return result;
127 }
128
compress(const StaticContext::Ptr & context)129 Expression::Ptr NodeComparison::compress(const StaticContext::Ptr &context)
130 {
131 const Expression::Ptr me(PairContainer::compress(context));
132
133 if(me != this)
134 /* We're already rewritten. */
135 return me;
136
137 if(m_operand1->staticType()->cardinality().isEmpty() ||
138 m_operand2->staticType()->cardinality().isEmpty())
139 {
140 // TODO issue a warning in the @p context saying that one of the operands
141 // were empty, and that the expression always result in the empty sequence
142 // (which never is the intent, right?).
143 return EmptySequence::create(this, context);
144 }
145
146 return Expression::Ptr(this);
147 }
148
displayName(const QXmlNodeModelIndex::DocumentOrder op)149 QString NodeComparison::displayName(const QXmlNodeModelIndex::DocumentOrder op)
150 {
151 switch(op)
152 {
153 case QXmlNodeModelIndex::Is:
154 return QLatin1String("is");
155 case QXmlNodeModelIndex::Precedes:
156 return QLatin1String("<<");
157 default:
158 {
159 Q_ASSERT(op == QXmlNodeModelIndex::Follows);
160 return QLatin1String(">>");
161 }
162 }
163 }
164
staticType() const165 SequenceType::Ptr NodeComparison::staticType() const
166 {
167 if(m_operand1->staticType()->cardinality().allowsEmpty() ||
168 m_operand2->staticType()->cardinality().allowsEmpty())
169 return CommonSequenceTypes::ZeroOrOneBoolean;
170 else
171 return CommonSequenceTypes::ExactlyOneBoolean;
172 }
173
operatorID() const174 QXmlNodeModelIndex::DocumentOrder NodeComparison::operatorID() const
175 {
176 return m_op;
177 }
178
accept(const ExpressionVisitor::Ptr & visitor) const179 ExpressionVisitorResult::Ptr NodeComparison::accept(const ExpressionVisitor::Ptr &visitor) const
180 {
181 return visitor->visit(this);
182 }
183
184 QT_END_NAMESPACE
185