mirror of
https://github.com/tristanpenman/valijson.git
synced 2025-01-19 00:46:03 +01:00
Refactor DependenciesConstraint to use custom allocator, hidden behind a more robust encapsulation strategy
This commit is contained in:
Tristan Penman
parent
76f8655d21
commit
c7f2f9b802
@ -5,6 +5,8 @@
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#include <valijson/constraints/constraint.hpp>
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#include <valijson/constraints/constraint_visitor.hpp>
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#include <valijson/internal/custom_allocator.hpp>
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namespace valijson {
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namespace constraints {
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@ -18,6 +20,17 @@ namespace constraints {
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template<typename ConstraintType>
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struct BasicConstraint: Constraint
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{
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typedef internal::CustomAllocator<void *> Allocator;
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typedef std::basic_string<char, std::char_traits<char>,
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internal::CustomAllocator<char> > String;
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BasicConstraint()
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: allocator() { }
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BasicConstraint(Allocator::CustomAlloc allocFn, Allocator::CustomFree freeFn)
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: allocator(allocFn, freeFn) { }
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virtual ~BasicConstraint<ConstraintType>() { }
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virtual bool accept(ConstraintVisitor &visitor) const
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@ -41,6 +54,10 @@ struct BasicConstraint: Constraint
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throw;
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}
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}
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protected:
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Allocator allocator;
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};
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} // namespace constraints
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@ -27,6 +27,7 @@
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#include <valijson/adapters/frozen_value.hpp>
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#include <valijson/constraints/basic_constraint.hpp>
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#include <valijson/internal/custom_allocator.hpp>
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#include <valijson/schema.hpp>
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namespace valijson {
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@ -77,23 +78,113 @@ struct AnyOfConstraint: BasicConstraint<AnyOfConstraint>
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* A dependency constraint ensures that a given property is valid only if the
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* properties that it depends on are present.
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*/
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struct DependenciesConstraint: BasicConstraint<DependenciesConstraint>
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class DependenciesConstraint: public BasicConstraint<DependenciesConstraint>
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{
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// A mapping from property names to the set of names of their dependencies
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typedef std::set<std::string> Dependencies;
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typedef std::map<std::string, Dependencies> PropertyDependenciesMap;
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public:
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DependenciesConstraint()
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: propertyDependencies(allocator),
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schemaDependencies(allocator)
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{ }
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// A mapping from property names to dependent schemas
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typedef std::map<std::string, const Subschema *>
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PropertyDependentSchemasMap;
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DependenciesConstraint(CustomAlloc allocFn, CustomFree freeFn)
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: BasicConstraint(allocFn, freeFn),
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propertyDependencies(allocator),
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schemaDependencies(allocator)
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{ }
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DependenciesConstraint(const PropertyDependenciesMap &dependencies,
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const PropertyDependentSchemasMap &dependentSchemas)
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: dependencies(dependencies),
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dependentSchemas(dependentSchemas) { }
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template<typename StringType>
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DependenciesConstraint & addPropertyDependency(
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const StringType &propertyName,
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const StringType &dependencyName)
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{
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const String key(propertyName.c_str(), allocator);
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PropertyDependencies::iterator itr = propertyDependencies.find(key);
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if (itr == propertyDependencies.end()) {
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itr = propertyDependencies.insert(PropertyDependencies::value_type(
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key, PropertySet(allocator))).first;
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}
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const PropertyDependenciesMap dependencies;
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const PropertyDependentSchemasMap dependentSchemas;
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itr->second.insert(String(dependencyName.c_str(), allocator));
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return *this;
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}
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template<typename StringType, typename ContainerType>
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DependenciesConstraint & addPropertyDependencies(
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const StringType &propertyName,
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const ContainerType &dependencyNames)
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{
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const String key(propertyName.c_str(), allocator);
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PropertyDependencies::iterator itr = propertyDependencies.find(key);
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if (itr == propertyDependencies.end()) {
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itr = propertyDependencies.insert(PropertyDependencies::value_type(
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key, PropertySet(allocator))).first;
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}
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typedef typename ContainerType::value_type ValueType;
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BOOST_FOREACH( const ValueType &dependencyName, dependencyNames ) {
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itr->second.insert(String(dependencyName.c_str(), allocator));
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}
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return *this;
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}
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template<typename StringType>
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DependenciesConstraint & addSchemaDependency(
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const StringType &propertyName,
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const Subschema *schemaDependency)
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{
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if (schemaDependencies.insert(SchemaDependencies::value_type(
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String(propertyName.c_str(), allocator),
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schemaDependency)).second) {
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return *this;
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}
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throw std::runtime_error(
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"Dependencies constraint already contains a dependent "
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"schema for the property '" + propertyName + "'");
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}
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template<typename FunctorType>
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bool applyToPropertyDependencies(const FunctorType &fn) const
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{
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BOOST_FOREACH( const PropertyDependencies::value_type &v,
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propertyDependencies ) {
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if (!fn(v.first, v.second)) {
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return false;
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}
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}
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return true;
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}
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template<typename FunctorType>
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bool applyToSchemaDependencies(const FunctorType &fn) const
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{
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BOOST_FOREACH( const SchemaDependencies::value_type &v,
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schemaDependencies ) {
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if (!fn(v.first, v.second)) {
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return false;
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}
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}
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return true;
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}
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private:
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typedef std::set<String, std::less<String>, Allocator> PropertySet;
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typedef std::map<String, PropertySet, std::less<String>, Allocator>
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PropertyDependencies;
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typedef std::map<String, const Subschema *, std::less<String>, Allocator>
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SchemaDependencies;
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/// Mapping from property names to their property-based dependencies
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PropertyDependencies propertyDependencies;
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/// Mapping from property names to their schema-based dependencies
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SchemaDependencies schemaDependencies;
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};
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/**
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@ -7,7 +7,6 @@ namespace constraints {
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struct AllOfConstraint;
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struct AnyOfConstraint;
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struct DependenciesConstraint;
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struct EnumConstraint;
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struct ItemsConstraint;
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struct FormatConstraint;
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@ -28,6 +27,8 @@ struct RequiredConstraint;
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struct TypeConstraint;
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struct UniqueItemsConstraint;
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class DependenciesConstraint;
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/// Interface to allow usage of the visitor pattern with Constraints
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class ConstraintVisitor
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{
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111
include/valijson/internal/custom_allocator.hpp
Normal file
111
include/valijson/internal/custom_allocator.hpp
Normal file
@ -0,0 +1,111 @@
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#ifndef __VALIJSON_CUSTOM_ALLOCATOR_HPP
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#define __VALIJSON_CUSTOM_ALLOCATOR_HPP
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namespace valijson {
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namespace internal {
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template<class T>
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class CustomAllocator
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{
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public:
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/// Typedef for custom new-/malloc-like function
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typedef void * (*CustomAlloc)(size_t size);
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/// Typedef for custom free-like function
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typedef void (*CustomFree)(void *);
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// Standard allocator typedefs
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typedef T value_type;
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typedef T* pointer;
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typedef const T* const_pointer;
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typedef T& reference;
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typedef const T& const_reference;
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typedef std::size_t size_type;
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typedef std::ptrdiff_t difference_type;
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typedef std::true_type propagate_on_container_move_assignment;
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template<typename U>
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struct rebind
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{
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typedef CustomAllocator<U> other;
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};
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CustomAllocator()
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: allocFn(::operator new),
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freeFn(::operator delete) { }
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CustomAllocator(CustomAlloc allocFn, CustomFree freeFn)
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: allocFn(allocFn),
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freeFn(freeFn) { }
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CustomAllocator(const CustomAllocator &other)
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: allocFn(other.allocFn),
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freeFn(other.freeFn) { }
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template<typename U>
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CustomAllocator(CustomAllocator<U> const &other)
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: allocFn(other.allocFn),
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freeFn(other.freeFn) { }
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CustomAllocator & operator=(const CustomAllocator &other)
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{
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allocFn = other.allocFn;
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freeFn = other.freeFn;
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}
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pointer address(reference r)
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{
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return &r;
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}
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const_pointer address(const_reference r)
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{
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return &r;
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}
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pointer allocate(size_type cnt,
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typename std::allocator<void>::const_pointer = 0)
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{
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return reinterpret_cast<pointer>(allocFn(cnt * sizeof(T)));
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}
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void deallocate(pointer p, size_type)
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{
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freeFn(p);
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}
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size_type max_size() const
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{
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return std::numeric_limits<size_type>::max() / sizeof(T);
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}
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void construct(pointer p, const T& t)
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{
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new(p) T(t);
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}
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void destroy(pointer p)
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{
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p->~T();
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}
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bool operator==(CustomAllocator const &other)
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{
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return other.allocFn == allocFn && other.freeFn == freeFn;
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}
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bool operator!=(CustomAllocator const &other)
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{
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return !operator==(other);
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}
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CustomAlloc allocFn;
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CustomFree freeFn;
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};
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} // end namespace internal
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} // end namespace valijson
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#endif
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@ -617,8 +617,7 @@ private:
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throw std::runtime_error("Expected object value for 'dependencies' constraint.");
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}
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constraints::DependenciesConstraint::PropertyDependenciesMap pdm;
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constraints::DependenciesConstraint::PropertyDependentSchemasMap pdsm;
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constraints::DependenciesConstraint dependenciesConstraint;
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// Process each of the dependency mappings defined by the object
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BOOST_FOREACH ( const typename AdapterType::ObjectMember member, node.asObject() ) {
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@ -632,16 +631,19 @@ private:
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// be detected.
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if (member.second.maybeArray()) {
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// Parse an array of dependency names
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constraints::DependenciesConstraint::Dependencies &dependencies = pdm[member.first];
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std::vector<std::string> dependentPropertyNames;
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BOOST_FOREACH( const AdapterType dependencyName, member.second.asArray() ) {
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if (dependencyName.maybeString()) {
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dependencies.insert(dependencyName.getString());
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dependentPropertyNames.push_back(dependencyName.getString());
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} else {
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throw std::runtime_error("Expected string value in dependency list of property '" +
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member.first + "' in 'dependencies' constraint.");
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}
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}
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dependenciesConstraint.addPropertyDependencies(member.first,
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dependentPropertyNames);
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// If the value of dependency mapping could not be processed as an
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// array, we'll try to process it as an object instead. Note that
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// strict type comparison is used here, since we've already
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@ -651,15 +653,17 @@ private:
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} else if (member.second.isObject()) {
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// Parse dependent subschema
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const Subschema *childSubschema = rootSchema.createSubschema();
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pdsm[member.first] = childSubschema;
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populateSchema<AdapterType>(rootSchema, rootNode, member.second,
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*childSubschema, currentScope, nodePath, fetchDoc);
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dependenciesConstraint.addSchemaDependency(member.first,
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childSubschema);
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// If we're supposed to be parsing a Draft3 schema, then the value
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// of the dependency mapping can also be a string containing the
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// name of a single dependency.
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} else if (version == kDraft3 && member.second.isString()) {
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pdm[member.first].insert(member.second.getString());
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dependenciesConstraint.addPropertyDependency(member.first,
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member.second.getString());
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// All other types result in an exception being thrown.
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} else {
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@ -667,7 +671,7 @@ private:
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}
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}
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return constraints::DependenciesConstraint(pdm, pdsm);
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return dependenciesConstraint;
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}
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/**
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@ -176,16 +176,21 @@ public:
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}
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/**
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* @brief Validate against the dependencies constraint represented by a
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* DependenciesConstraint object.
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* @brief Validate current node against a 'dependencies' constraint
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*
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* A dependencies constraint can specify either a mapping of attribute names
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* to their dependencies, or a mapping of attribute names to child schemas
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* that must be satisfied if a given attribute is present.
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* A 'dependencies' constraint can be used to specify property-based or
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* schema-based dependencies that must be fulfilled when a particular
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* property is present in an object.
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*
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* @param constraint Constraint that the target must validate against.
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* Property-based dependencies define a set of properties that must be
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* present in addition to a particular property, whereas a schema-based
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* dependency defines an additional schema that the current document must
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* validate against.
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*
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* @return true if validation passes, false otherwise.
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* @param constraint DependenciesConstraint that the current node
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* must validate against
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*
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* @return \c true if validation passes; \c false otherwise
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*/
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virtual bool visit(const DependenciesConstraint &constraint)
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{
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@ -194,54 +199,28 @@ public:
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return true;
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}
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// Typedef and reference for conciseness in nested loops
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typedef DependenciesConstraint::PropertyDependenciesMap PDM;
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const PDM &deps = constraint.dependencies;
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typedef DependenciesConstraint::PropertyDependentSchemasMap PDSM;
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const PDSM &depSchemas = constraint.dependentSchemas;
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// Get access to the target as an object
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// Object to be validated
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const typename AdapterType::Object object = target.asObject();
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// Flag used to track validation status if errors are non-fatal
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// Cleared if validation fails
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bool validated = true;
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// For each property in the object, check for a list of dependencies in
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// the constraint object and verify that the dependencies have been
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// satisfied.
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BOOST_FOREACH( const typename AdapterType::ObjectMember m, object ) {
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// Iterate over all dependent properties defined by this constraint,
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// invoking the DependentPropertyValidator functor once for each
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// set of dependent properties
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constraint.applyToPropertyDependencies(ValidatePropertyDependencies(
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object, context, results, &validated));
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if (!results && !validated) {
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return false;
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}
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// Check for this property in the dependency map. If it is not
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// present, we can move on to the next one...
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PDM::const_iterator itr = deps.find(m.first);
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if (itr != deps.end()) {
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BOOST_FOREACH( const std::string &name, itr->second ) {
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if (object.find(name) == object.end()) {
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if (!results) {
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return false;
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}
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validated = false;
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results->pushError(context, "Missing dependency '" + name + "'.");
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}
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}
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}
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// Check for this property in the dependent schemas map. If it is
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// present then we need to validate the current target against the
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// dependent schema.
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PDSM::const_iterator depSchemasItr = depSchemas.find(m.first);
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if (depSchemasItr != depSchemas.end()) {
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const Subschema *subschema = depSchemasItr->second;
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if (!validateSchema(*subschema)) {
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if (results) {
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results->pushError(context, "Failed to validate against dependent schema.");
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validated = false;
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} else {
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return false;
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}
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}
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}
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// Iterate over all dependent schemas defined by this constraint,
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// invoking the DependentSchemaValidator function once for each schema
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// that must be validated if a given property is present
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constraint.applyToSchemaDependencies(ValidateSchemaDependencies(
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object, context, *this, results, &validated));
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if (!results && !validated) {
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return false;
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}
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return validated;
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@ -1087,6 +1066,101 @@ public:
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private:
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struct ValidatePropertyDependencies
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{
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ValidatePropertyDependencies(
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const typename AdapterType::Object &object,
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const std::vector<std::string> &context,
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ValidationResults *results,
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bool *validated)
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: object(object),
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context(context),
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results(results),
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validated(validated) { }
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template<typename StringType, typename ContainerType>
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bool operator()(
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const StringType &propertyName,
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const ContainerType &dependencyNames) const
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{
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const std::string propertyNameKey(propertyName.c_str());
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if (object.find(propertyNameKey) == object.end()) {
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return true;
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}
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typedef typename ContainerType::value_type ValueType;
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BOOST_FOREACH( const ValueType &dependencyName, dependencyNames ) {
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const std::string dependencyNameKey(dependencyName.c_str());
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if (object.find(dependencyNameKey) == object.end()) {
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if (validated) {
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*validated = false;
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}
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if (results) {
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results->pushError(context, "Missing dependency '" +
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dependencyNameKey + "'.");
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} else {
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return false;
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}
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}
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}
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return true;
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}
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private:
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const typename AdapterType::Object &object;
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const std::vector<std::string> &context;
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ValidationResults * const results;
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bool * const validated;
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};
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struct ValidateSchemaDependencies
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{
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ValidateSchemaDependencies(
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const typename AdapterType::Object &object,
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const std::vector<std::string> &context,
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ValidationVisitor &validationVisitor,
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ValidationResults *results,
|
||||
bool *validated)
|
||||
: object(object),
|
||||
context(context),
|
||||
validationVisitor(validationVisitor),
|
||||
results(results),
|
||||
validated(validated) { }
|
||||
|
||||
template<typename StringType>
|
||||
bool operator()(
|
||||
const StringType &propertyName,
|
||||
const Subschema *schemaDependency) const
|
||||
{
|
||||
const std::string propertyNameKey(propertyName.c_str());
|
||||
if (object.find(propertyNameKey) == object.end()) {
|
||||
return true;
|
||||
}
|
||||
|
||||
if (!validationVisitor.validateSchema(*schemaDependency)) {
|
||||
if (validated) {
|
||||
*validated = false;
|
||||
}
|
||||
if (results) {
|
||||
results->pushError(context,
|
||||
"Failed to validate against dependent schema.");
|
||||
} else {
|
||||
return false;
|
||||
}
|
||||
}
|
||||
|
||||
return true;
|
||||
}
|
||||
|
||||
private:
|
||||
const typename AdapterType::Object &object;
|
||||
const std::vector<std::string> &context;
|
||||
ValidationVisitor &validationVisitor;
|
||||
ValidationResults * const results;
|
||||
bool * const validated;
|
||||
};
|
||||
|
||||
/**
|
||||
* @brief Callback function that passes a visitor to a constraint.
|
||||
*
|
||||
|
||||
@ -236,6 +236,7 @@
|
||||
6AD030F51B03FD9900B957E5 /* LICENSE */ = {isa = PBXFileReference; lastKnownFileType = text; name = LICENSE; path = ../LICENSE; sourceTree = "<group>"; };
|
||||
6AE1D76617E3F993008CF38C /* custom_schema.cpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.cpp; path = custom_schema.cpp; sourceTree = "<group>"; };
|
||||
6AEFECC81AB53F1000275614 /* libjsoncpp.a */ = {isa = PBXFileReference; explicitFileType = archive.ar; includeInIndex = 0; path = libjsoncpp.a; sourceTree = BUILT_PRODUCTS_DIR; };
|
||||
6AF3F5071C2D874F001B3445 /* custom_allocator.hpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.h; name = custom_allocator.hpp; path = internal/custom_allocator.hpp; sourceTree = "<group>"; };
|
||||
6AF70AE118FE71F600342325 /* gtest-death-test.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = "gtest-death-test.h"; sourceTree = "<group>"; };
|
||||
6AF70AE218FE71F600342325 /* gtest-message.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = "gtest-message.h"; sourceTree = "<group>"; };
|
||||
6AF70AE318FE71F600342325 /* gtest-param-test.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = "gtest-param-test.h"; sourceTree = "<group>"; };
|
||||
@ -362,6 +363,7 @@
|
||||
6A506D1D1AF88D5E00C2C818 /* internal */ = {
|
||||
isa = PBXGroup;
|
||||
children = (
|
||||
6AF3F5071C2D874F001B3445 /* custom_allocator.hpp */,
|
||||
6A506D1E1AF88D8700C2C818 /* json_pointer.hpp */,
|
||||
6A34698C1BD109A900C97DA2 /* json_reference.hpp */,
|
||||
6A356B0D1C1CFD020007EB8B /* uri.hpp */,
|
||||
|
||||
Loading…
x
Reference in New Issue
Block a user