Mihaela Mihaljevic
85d435d035
Running the full W3C XSTS archive to completion exposed three crash and hang classes, now fixed with regression tests, which unblocked the #129 first measurement. - Content-model and regex NFA builders now cap total state count (2^20), degrading further occurrence/quantifier repetition to star, so nested high-maxOccurs schemas no longer OOM (was 8 GB on the MS Particles set). - Content-model validation advances one active state-set per child instead of re-walking the prefix each time, removing the O(children^2) spin. - Regex class subtraction [abc-[b]] no longer traps on a reversed range, and a reversed range such as [z-a] is rejected cleanly. XSTS first measurement baselined: 75 valid schemas rejected, 2467 invalid schemas accepted, 604 valid instances rejected, 582 invalid instances accepted across 14383 groups. The suite runs green in 8s, opt-in via XSTS_ROOT. Refs #129, #122.
373 lines
18 KiB
Swift
373 lines
18 KiB
Swift
/// File-scope aliases for the XSD complex-type validator, kept out of the
|
|
/// namespace to avoid nesting a type two levels deep.
|
|
typealias XSDFailure = PureXML.Validation.ValidationError
|
|
typealias XSDPath = [PureXML.Validation.PathKey]
|
|
private typealias XSDGroup = PureXML.Schema.Group
|
|
private typealias XSDTerm = PureXML.Schema.Term
|
|
private typealias XSDTermLabel = PureXML.Schema.TermLabel
|
|
private typealias XSDProcessContents = PureXML.Schema.ProcessContents
|
|
private typealias XSDElementType = PureXML.Schema.ElementType
|
|
private typealias XSDWildcard = PureXML.Schema.Wildcard
|
|
|
|
public extension PureXML.Schema {
|
|
/// Validates an element against a ``ComplexType``: its attribute uses, its
|
|
/// content model, and, recursively, each child element against the type
|
|
/// declared for its name. Every violation is located by the element's coding
|
|
/// path, and the results are ``PureXML/Validation/ValidationError`` values.
|
|
struct ComplexValidator {
|
|
/// The named type table that `ElementType.typeReference` resolves against.
|
|
let types: [String: ElementType]
|
|
/// Local names of elements declared `nillable="true"`.
|
|
private let nillableElements: Set<String>
|
|
/// The `default`/`fixed` value constraint declared on each element name.
|
|
private let elementConstraints: [String: ValueConstraint]
|
|
/// Local names of complex types declared `abstract="true"`.
|
|
let abstractTypes: Set<String>
|
|
/// Derivation methods each named type forbids through `xsi:type`.
|
|
let typeBlock: [String: Set<DerivationMethod>]
|
|
/// Each named complex type's base and derivation method.
|
|
let typeDerivation: [String: TypeDerivation]
|
|
|
|
public init(
|
|
types: [String: ElementType] = [:],
|
|
nillableElements: Set<String> = [],
|
|
elementConstraints: [String: ValueConstraint] = [:],
|
|
abstractTypes: Set<String> = [],
|
|
typeBlock: [String: Set<DerivationMethod>] = [:],
|
|
typeDerivation: [String: TypeDerivation] = [:],
|
|
) {
|
|
self.types = types
|
|
self.nillableElements = nillableElements
|
|
self.elementConstraints = elementConstraints
|
|
self.abstractTypes = abstractTypes
|
|
self.typeBlock = typeBlock
|
|
self.typeDerivation = typeDerivation
|
|
}
|
|
|
|
/// Validates `element` against `type` at `path`, one error per violation.
|
|
public func validate(
|
|
_ element: PureXML.Model.Element,
|
|
against type: ComplexType,
|
|
at path: [PureXML.Validation.PathKey] = [],
|
|
) -> [PureXML.Validation.ValidationError] {
|
|
var errors: [XSDFailure] = []
|
|
validateAttributes(element, type, at: path, into: &errors)
|
|
// An xsi:nil element keeps its attribute obligations but must have no
|
|
// content; its content model is not otherwise checked.
|
|
if let nilErrors = nilErrors(element, at: path) {
|
|
return errors + nilErrors
|
|
}
|
|
validateContent(element, type.content, at: path, into: &errors)
|
|
errors += elementFixedErrors(element, at: path)
|
|
return errors
|
|
}
|
|
|
|
/// The errors from an `xsi:nil="true"` element: rejecting it when the
|
|
/// element is not nillable, or when it carries content. Returns nil when
|
|
/// the element is not nilled.
|
|
func nilErrors(_ element: PureXML.Model.Element, at path: XSDPath) -> [XSDFailure]? {
|
|
guard Self.isNil(element) else { return nil }
|
|
let name = element.name.localName
|
|
if !nillableElements.contains(name) {
|
|
return [XSDFailure(reason: "element '\(name)' is not nillable but has xsi:nil", at: path)]
|
|
}
|
|
if Self.hasContent(element) {
|
|
return [XSDFailure(reason: "nil element '\(name)' must be empty", at: path)]
|
|
}
|
|
return []
|
|
}
|
|
|
|
/// The error from a `fixed` element value constraint: the element's text
|
|
/// must equal the fixed value.
|
|
func elementFixedErrors(_ element: PureXML.Model.Element, at path: XSDPath) -> [XSDFailure] {
|
|
guard let fixed = elementConstraints[element.name.localName]?.fixedValue else { return [] }
|
|
let text = Self.textContent(element)
|
|
return text == fixed ? [] : [XSDFailure(reason: "element '\(element.name.localName)' is fixed and must be '\(fixed)'", at: path)]
|
|
}
|
|
|
|
/// Validates `element` against any element type at `path`, resolving a
|
|
/// `typeReference` through the type table.
|
|
public func validate(
|
|
_ element: PureXML.Model.Element,
|
|
as type: ElementType,
|
|
at path: [PureXML.Validation.PathKey] = [],
|
|
) -> [PureXML.Validation.ValidationError] {
|
|
var errors: [XSDFailure] = []
|
|
validateChild(element, against: type, at: path, into: &errors)
|
|
return errors
|
|
}
|
|
|
|
// MARK: Attributes
|
|
|
|
func validateAttributes(
|
|
_ element: PureXML.Model.Element,
|
|
_ type: ComplexType,
|
|
at path: XSDPath,
|
|
into errors: inout [XSDFailure],
|
|
) {
|
|
let present = element.attributes.filter { !Self.isNamespaceDeclaration($0) && !Self.isSchemaInstanceAttribute($0) }
|
|
for use in type.attributes {
|
|
let match = present.first { Self.sameName($0.name, use.name) }
|
|
if let match {
|
|
if let error = use.type.validate(match.value) {
|
|
errors.append(XSDFailure(reason: "attribute '\(use.name.localName)': \(error)", at: path))
|
|
}
|
|
if let fixed = use.valueConstraint?.fixedValue, match.value != fixed {
|
|
errors.append(XSDFailure(reason: "attribute '\(use.name.localName)' is fixed and must be '\(fixed)'", at: path))
|
|
}
|
|
} else if use.required {
|
|
errors.append(XSDFailure(reason: "missing required attribute '\(use.name.localName)'", at: path))
|
|
}
|
|
}
|
|
// An undeclared attribute is allowed only if an xs:anyAttribute wildcard
|
|
// admits its namespace.
|
|
for attribute in present where !type.attributes.contains(where: { Self.sameName($0.name, attribute.name) }) {
|
|
if type.attributeWildcard?.admits(attribute.name) == true { continue }
|
|
errors.append(XSDFailure(reason: "undeclared attribute '\(attribute.name.localName)'", at: path))
|
|
}
|
|
}
|
|
|
|
// MARK: Content
|
|
|
|
private func validateContent(
|
|
_ element: PureXML.Model.Element,
|
|
_ content: ContentType,
|
|
at path: XSDPath,
|
|
into errors: inout [XSDFailure],
|
|
) {
|
|
let children = element.children.compactMap(\.element)
|
|
switch content {
|
|
case .empty:
|
|
if !children.isEmpty { errors.append(XSDFailure(reason: "element must be empty", at: path)) }
|
|
rejectText(element, at: path, into: &errors)
|
|
case let .simpleContent(type):
|
|
if !children.isEmpty { errors.append(XSDFailure(reason: "element must not have children", at: path)) }
|
|
if let error = type.validate(Self.textContent(element)) {
|
|
errors.append(XSDFailure(reason: "content: \(error)", at: path))
|
|
}
|
|
case let .elementOnly(particle):
|
|
rejectText(element, at: path, into: &errors)
|
|
validateParticle(particle, children: children, at: path, into: &errors)
|
|
case let .mixed(particle):
|
|
validateParticle(particle, children: children, at: path, into: &errors)
|
|
}
|
|
}
|
|
|
|
func rejectText(_ element: PureXML.Model.Element, at path: XSDPath, into errors: inout [XSDFailure]) {
|
|
guard !Self.textContent(element).isEmpty else { return }
|
|
errors.append(XSDFailure(reason: "element must not contain text", at: path))
|
|
}
|
|
|
|
// MARK: Particles
|
|
|
|
private func validateParticle(
|
|
_ particle: Particle,
|
|
children: [PureXML.Model.Element],
|
|
at path: XSDPath,
|
|
into errors: inout [XSDFailure],
|
|
) {
|
|
// Locate each content-model violation at the offending child (or the
|
|
// missing one), with a recovery hint, rather than one opaque failure,
|
|
// then still validate every well-placed child's own content.
|
|
if case let .group(group) = particle.term, group.compositor == .all {
|
|
allStructureErrors(group, children: children, at: path, into: &errors)
|
|
} else {
|
|
sequenceStructureErrors(particle, children: children, at: path, into: &errors)
|
|
}
|
|
validateChildren(
|
|
children,
|
|
childTypes: Self.elementTypes(in: particle.term),
|
|
wildcard: Self.wildcard(in: particle.term),
|
|
at: path,
|
|
into: &errors,
|
|
)
|
|
}
|
|
|
|
private func validateChildren(
|
|
_ children: [PureXML.Model.Element],
|
|
childTypes: [String: ElementType],
|
|
wildcard: ProcessContents?,
|
|
at path: XSDPath,
|
|
into errors: inout [XSDFailure],
|
|
) {
|
|
let steps = Self.childSteps(children)
|
|
for (child, step) in zip(children, steps) {
|
|
if let declared = childTypes[Self.key(child.name)] {
|
|
validateChild(child, against: declared, at: path + [step], into: &errors)
|
|
} else if let wildcard {
|
|
// The structure already matched, so an undeclared child here was
|
|
// admitted by a wildcard; process its content per the wildcard.
|
|
validateWildcardChild(child, processContents: wildcard, at: path + [step], into: &errors)
|
|
}
|
|
}
|
|
}
|
|
|
|
/// Validates a wildcard-matched child by its `processContents`: skip does
|
|
/// nothing, lax validates against a global declaration when one exists, and
|
|
/// strict requires one.
|
|
private func validateWildcardChild(
|
|
_ child: PureXML.Model.Element,
|
|
processContents: ProcessContents,
|
|
at path: XSDPath,
|
|
into errors: inout [XSDFailure],
|
|
) {
|
|
switch processContents {
|
|
case .skip:
|
|
return
|
|
case .lax:
|
|
if let declaration = types["element:\(child.name.localName)"] {
|
|
validateChild(child, against: declaration, at: path, into: &errors)
|
|
}
|
|
case .strict:
|
|
guard let declaration = types["element:\(child.name.localName)"] else {
|
|
errors.append(XSDFailure(reason: "no declaration for wildcard-matched element '\(child.name.localName)'", at: path))
|
|
return
|
|
}
|
|
validateChild(child, against: declaration, at: path, into: &errors)
|
|
}
|
|
}
|
|
|
|
private func validateChild(
|
|
_ child: PureXML.Model.Element,
|
|
against declared: ElementType,
|
|
at path: XSDPath,
|
|
into errors: inout [XSDFailure],
|
|
) {
|
|
// An instance `xsi:type` overrides the declared type, provided the named
|
|
// type exists in the schema. Resolve to the type itself rather than a
|
|
// reference so re-entry does not re-read the same xsi:type. A `block` on
|
|
// the declared type can forbid the substitution; an abstract declared
|
|
// type requires one.
|
|
if let blocked = blockedSubstitutionError(declared: declared, child: child, at: path) {
|
|
errors.append(blocked)
|
|
return
|
|
}
|
|
if case let .typeReference(name) = declared, let missing = abstractTypeError(named: name, child: child, at: path) {
|
|
errors.append(missing)
|
|
return
|
|
}
|
|
guard let declared = overriddenType(declared, for: child, at: path, into: &errors) else { return }
|
|
switch declared {
|
|
case let .simple(simple):
|
|
if let nilErrors = nilErrors(child, at: path) {
|
|
errors += nilErrors
|
|
return
|
|
}
|
|
if !child.children.compactMap(\.element).isEmpty {
|
|
errors.append(XSDFailure(reason: "'\(child.name.localName)' must not have children", at: path))
|
|
}
|
|
if let error = simple.validate(Self.textContent(child)) {
|
|
errors.append(XSDFailure(reason: "'\(child.name.localName)': \(error)", at: path))
|
|
}
|
|
errors += elementFixedErrors(child, at: path)
|
|
case let .complex(complex):
|
|
errors.append(contentsOf: validate(child, against: complex, at: path))
|
|
case .typeReference:
|
|
validateResolvedReference(declared, child, at: path, into: &errors)
|
|
}
|
|
}
|
|
|
|
/// The declared type after an `xsi:type` override. An override naming an
|
|
/// undeclared type appends an error and returns nil, not a silent fallback
|
|
/// to the declared type.
|
|
private func overriddenType(
|
|
_ declared: ElementType,
|
|
for child: PureXML.Model.Element,
|
|
at path: XSDPath,
|
|
into errors: inout [XSDFailure],
|
|
) -> ElementType? {
|
|
guard let overriding = Self.xsiTypeName(child) else { return declared }
|
|
guard let resolved = types[overriding] else {
|
|
errors.append(XSDFailure(reason: "unknown xsi:type '\(overriding)' on '\(child.name.localName)'", at: path))
|
|
return nil
|
|
}
|
|
return resolved
|
|
}
|
|
|
|
/// Validates a child against a `typeReference` through the shared resolver,
|
|
/// reporting an unknown name or a circular chain as a located error.
|
|
private func validateResolvedReference(
|
|
_ declared: ElementType,
|
|
_ child: PureXML.Model.Element,
|
|
at path: XSDPath,
|
|
into errors: inout [XSDFailure],
|
|
) {
|
|
switch resolveReference(declared) {
|
|
case let .unknown(name):
|
|
errors.append(XSDFailure(reason: "unknown type '\(name)'", at: path))
|
|
case let .circular(name):
|
|
errors.append(XSDFailure(reason: "circular type reference '\(name)'", at: path))
|
|
case let .resolved(resolved):
|
|
validateChild(child, against: resolved, at: path, into: &errors)
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
/// Located content-model diagnostics: pinpoint which child breaks the model and
|
|
/// what was expected there, so an editor shows placed errors with recovery hints
|
|
/// rather than one opaque "content does not match" per element.
|
|
extension PureXML.Schema.ComplexValidator {
|
|
/// Walks the children through the content automaton, flagging the first child
|
|
/// the follow-set rejects, or the missing content when the sequence ends early.
|
|
func sequenceStructureErrors(_ particle: PureXML.Schema.Particle, children: [PureXML.Model.Element], at path: XSDPath, into errors: inout [XSDFailure]) {
|
|
let nfa = PureXML.Schema.ContentNFABuilder.build(particle)
|
|
let steps = Self.childSteps(children)
|
|
// Advance one active state-set across the children rather than re-walking
|
|
// the prefix per child (which is quadratic over the content model, #129).
|
|
var current = nfa.startStates()
|
|
for (index, child) in children.enumerated() {
|
|
guard let next = nfa.step(current, over: child.name) else {
|
|
let allowed = nfa.admissible(from: current)
|
|
errors.append(XSDFailure(reason: "element '\(child.name.localName)' is not allowed here\(Self.expectation(allowed))", at: path + [steps[index]]))
|
|
return
|
|
}
|
|
current = next
|
|
}
|
|
if !nfa.isComplete(current) {
|
|
errors.append(XSDFailure(reason: "content is incomplete\(Self.expectation(nfa.admissible(from: current)))", at: path))
|
|
}
|
|
}
|
|
|
|
/// Locates `all`-group violations: each child that is not an in-bounds member,
|
|
/// recovering past it, then each required member that never appeared.
|
|
func allStructureErrors(_ group: PureXML.Schema.Group, children: [PureXML.Model.Element], at path: XSDPath, into errors: inout [XSDFailure]) {
|
|
var counts = [Int](repeating: 0, count: group.particles.count)
|
|
let steps = Self.childSteps(children)
|
|
for (index, child) in children.enumerated() {
|
|
guard let position = group.particles.indices.first(where: { slot in
|
|
let member = group.particles[slot]
|
|
let room = member.maxOccurs.map { counts[slot] < $0 } ?? true
|
|
return room && Self.memberMatches(member.term, child.name)
|
|
}) else {
|
|
errors.append(XSDFailure(reason: "element '\(child.name.localName)' is not allowed here", at: path + [steps[index]]))
|
|
continue
|
|
}
|
|
counts[position] += 1
|
|
}
|
|
for (index, member) in group.particles.enumerated() where counts[index] < member.minOccurs {
|
|
if case let .element(name, _) = member.term {
|
|
errors.append(XSDFailure(reason: "element '\(name.localName)' is required but missing", at: path))
|
|
}
|
|
}
|
|
}
|
|
|
|
static func memberMatches(_ term: PureXML.Schema.Term, _ name: PureXML.Model.QualifiedName) -> Bool {
|
|
switch term {
|
|
case let .element(declared, _): declared.localName == name.localName && declared.namespaceURI == name.namespaceURI
|
|
case let .wildcard(wildcard): wildcard.admits(name)
|
|
case .group: false
|
|
}
|
|
}
|
|
|
|
/// A "; expected a, b" hint naming the elements the automaton accepts next.
|
|
static func expectation(_ labels: [PureXML.Schema.TermLabel]) -> String {
|
|
let names = labels.compactMap { label -> String? in
|
|
if case let .name(qualified) = label { return "<\(qualified.localName)>" }
|
|
return nil
|
|
}
|
|
let unique = Set(names).sorted()
|
|
return unique.isEmpty ? "" : "; expected \(unique.joined(separator: ", "))"
|
|
}
|
|
}
|