Identity-constraint selector and field XPath prefixes were resolved against
the instance document's namespace bindings, so a constraint declared with
xmlns:v="..." and a selector like .//v:vehicle matched nothing when the
instance used a default namespace instead of the v prefix. The selector then
selected no nodes, no key tuples were collected, and duplicate-key and
keyref violations went undetected.
Prefixes now resolve against the namespace bindings in scope where the
constraint is declared in the schema (XSD Part 1, Identity-constraint
Definition), captured at parse time onto IdentityConstraint. A QName field
value still compares using the instance's bindings, so QName keys are
unaffected.
XSTS invalid-instances-accepted 143 to 133: the idc004/5/6 namespaced
key/keyref cluster and namespace-resolution cases (idZ010 and kin), no other
bucket moved.
Validate XSD identity constraints over the instance document in a pass that
walks the tree alongside type validation:
- xs:unique requires the selected nodes' field tuples to be distinct, excluding
any node that is missing a field.
- xs:key additionally requires every field to be present.
- xs:keyref requires each tuple to equal a tuple of the named key or unique
visible in an enclosing scope, resolved through a stack of scope frames so a
keyref and the key it refers to may sit on the same element.
The selector and field XPaths run on the existing XPath engine, relative to the
declaring element and each selected node. Constraints are gathered for every
element declaration at any depth, keyed by element name.
Closes#67
