PureXML/Sources/Schema/SchemaDerivationControl.swift
Mihaela Mihaljevic 4460508924 fix(schema): inherit finalDefault as a complex type's final (#145)
A complex type without its own final attribute now inherits the schema's
finalDefault as its {final}, so finalDefault=#all or restriction/extension
blocks a complexContent restriction or extension derived from it. An explicit
final= overrides the default to empty. Complex types previously honoured only
an explicit final (elements already inherited finalDefault).

XSTS invalid-schemas-accepted 189 to 185, no other bucket moved.
2026-06-17 15:31:48 +02:00

78 lines
3.9 KiB
Swift

extension PureXML.Schema.XSDParser {
/// Value-space validity of the `final` and `block` derivation-control
/// attributes (XSD 1.0 Structures). Each is `#all` or a whitespace-separated
/// list of method tokens, but the admitted tokens depend on the component:
///
/// - element `final`: `extension`, `restriction`
/// - element `block`: `extension`, `restriction`, `substitution`
/// - complexType `final`/`block`: `extension`, `restriction`
/// - simpleType `final`: `list`, `union`, `restriction`
///
/// `methodSet` parses these leniently (ignoring unknown tokens and admitting
/// `substitution` everywhere), so `final="substitution"` on an element, a
/// misspelled or miscased token (`foo`, `#All`, `Extension`), or `#all` mixed
/// with other tokens was accepted (the elemF / st_final families). The token
/// list is now checked against the component's exact set.
static func derivationControlErrors(_ node: XSDTree, local: String) -> [String] {
var errors: [String] = []
for attribute in ["final", "block"] {
guard let allowed = derivationControlTokens["\(local)|\(attribute)"],
let raw = node.attributes.first(where: { $0.name.prefix == nil && $0.name.localName == attribute })?.value
else { continue }
if let reason = derivationListError(raw, allowed: allowed) {
errors.append("the '\(attribute)' value '\(raw)' on '\(local)' is not valid: \(reason)")
}
}
return errors
}
/// The exact method tokens each component admits in `final`/`block`.
private static let derivationControlTokens: [String: Set<String>] = [
"element|final": ["extension", "restriction"],
"element|block": ["extension", "restriction", "substitution"],
"complexType|final": ["extension", "restriction"],
"complexType|block": ["extension", "restriction"],
"simpleType|final": ["list", "union", "restriction"],
]
/// The reason a `final`/`block` value is invalid, or nil. `#all` stands alone;
/// otherwise every whitespace-separated token must be in `allowed` (exact case),
/// and `#all` may not be mixed with other tokens. An empty value is valid (no
/// control).
private static func derivationListError(_ raw: String, allowed: Set<String>) -> String? {
let tokens = raw.split(whereSeparator: \.isWhitespace).map(String.init)
if tokens == ["#all"] { return nil }
for token in tokens {
if token == "#all" { return "'#all' may not be combined with other tokens" }
if !allowed.contains(token) { return "'\(token)' is not one of \(allowed.sorted().joined(separator: ", "))" }
}
return nil
}
/// The `{final}` derivation methods of a complex type or element: its own
/// `final` when present, otherwise the enclosing schema's `finalDefault`, each
/// intersected with the extension/restriction methods these components admit. An
/// explicit `final=""` overrides the default back to no restriction.
static func finalMethods(of node: XSDTree) -> Set<PureXML.Schema.DerivationMethod> {
if let own = PureXML.Schema.XSDNode.attribute(node, "final") {
return methodSet(own).intersection([.extension, .restriction])
}
if let finalDefault = schemaFinalDefault(of: node) {
return methodSet(finalDefault).intersection([.extension, .restriction])
}
return []
}
/// The `finalDefault` of the `schema` enclosing `node`, or nil.
static func schemaFinalDefault(of node: XSDTree) -> String? {
var current: XSDTree? = node
while let element = current {
if element.name?.namespaceURI == xsdNamespace, PureXML.Schema.XSDNode.localName(element) == "schema" {
return PureXML.Schema.XSDNode.attribute(element, "finalDefault")
}
current = element.parent
}
return nil
}
}