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39 
40 #include "qitem_p.h"
41 #include "qboolean_p.h"
42 #include "qbuiltintypes_p.h"
43 #include "qcommonsequencetypes_p.h"
44 #include "qemptysequence_p.h"
45 #include "qoptimizationpasses_p.h"
46 
47 #include "qvaluecomparison_p.h"
48 
49 QT_BEGIN_NAMESPACE
50 
51 using namespace QPatternist;
52 
ValueComparison(const Expression::Ptr & op1,const AtomicComparator::Operator op,const Expression::Ptr & op2)53 ValueComparison::ValueComparison(const Expression::Ptr &op1,
54                                  const AtomicComparator::Operator op,
55                                  const Expression::Ptr &op2) : PairContainer(op1, op2),
56                                                                m_operator(op)
57 {
58 }
59 
60 /*! \internal */
~ValueComparison()61 ValueComparison::~ValueComparison()
62 {
63 }
64 
evaluateSingleton(const DynamicContext::Ptr & context) const65 Item ValueComparison::evaluateSingleton(const DynamicContext::Ptr &context) const
66 {
67     const Item it1(m_operand1->evaluateSingleton(context));
68     if(!it1)
69         return Item();
70 
71     const Item it2(m_operand2->evaluateSingleton(context));
72     if(!it2)
73         return Item();
74 
75     return Boolean::fromValue(flexibleCompare(it1, it2, context));
76 }
77 
typeCheck(const StaticContext::Ptr & context,const SequenceType::Ptr & reqType)78 Expression::Ptr ValueComparison::typeCheck(const StaticContext::Ptr &context,
79                                            const SequenceType::Ptr &reqType)
80 {
81     const Expression::Ptr me(PairContainer::typeCheck(context, reqType));
82     const ItemType::Ptr t1(m_operand1->staticType()->itemType());
83     const ItemType::Ptr t2(m_operand2->staticType()->itemType());
84     Q_ASSERT(t1);
85     Q_ASSERT(t2);
86 
87     if(*CommonSequenceTypes::Empty == *t1 ||
88        *CommonSequenceTypes::Empty == *t2)
89     {
90         return EmptySequence::create(this, context);
91     }
92     else
93     {
94         prepareComparison(fetchComparator(t1, t2, context));
95 
96         return me;
97     }
98 }
99 
compress(const StaticContext::Ptr & context)100 Expression::Ptr ValueComparison::compress(const StaticContext::Ptr &context)
101 {
102     const Expression::Ptr me(PairContainer::compress(context));
103 
104     if(me != this)
105         return me;
106 
107     if(isCaseInsensitiveCompare(m_operand1, m_operand2))
108         useCaseInsensitiveComparator();
109 
110     return me;
111 }
112 
isCaseInsensitiveCompare(Expression::Ptr & op1,Expression::Ptr & op2)113 bool ValueComparison::isCaseInsensitiveCompare(Expression::Ptr &op1, Expression::Ptr &op2)
114 {
115     Q_ASSERT(op1);
116     Q_ASSERT(op2);
117 
118     const ID iD = op1->id();
119 
120     if((iD == IDLowerCaseFN || iD == IDUpperCaseFN) && iD == op2->id())
121     {
122         /* Both are either fn:lower-case() or fn:upper-case(). */
123 
124         /* Replace the calls to the functions with its operands. */
125         op1 = op1->operands().first();
126         op2 = op2->operands().first();
127 
128         return true;
129     }
130     else
131         return false;
132 }
133 
optimizationPasses() const134 OptimizationPass::List ValueComparison::optimizationPasses() const
135 {
136     return OptimizationPasses::comparisonPasses;
137 }
138 
expectedOperandTypes() const139 SequenceType::List ValueComparison::expectedOperandTypes() const
140 {
141     SequenceType::List result;
142     result.append(CommonSequenceTypes::ZeroOrOneAtomicType);
143     result.append(CommonSequenceTypes::ZeroOrOneAtomicType);
144     return result;
145 }
146 
staticType() const147 SequenceType::Ptr ValueComparison::staticType() const
148 {
149     if(m_operand1->staticType()->cardinality().allowsEmpty() ||
150        m_operand2->staticType()->cardinality().allowsEmpty())
151         return CommonSequenceTypes::ZeroOrOneBoolean;
152     else
153         return CommonSequenceTypes::ExactlyOneBoolean;
154 }
155 
accept(const ExpressionVisitor::Ptr & visitor) const156 ExpressionVisitorResult::Ptr ValueComparison::accept(const ExpressionVisitor::Ptr &visitor) const
157 {
158     return visitor->visit(this);
159 }
160 
id() const161 Expression::ID ValueComparison::id() const
162 {
163     return IDValueComparison;
164 }
165 
166 QT_END_NAMESPACE
167