isUndeclaredReferenceType matched a no-namespace type/base/itemType/memberTypes
reference by local name, ignoring that an unprefixed QName with no default
xmlns resolves to the absent namespace: type="t" is {}t, not {urn:x}t where the
type is declared, so the reference does not resolve (XSD 1.0 §3.15.3). It now
mirrors isUndeclaredReferenceRef's nil-namespace branch: a no-namespace
reference is undeclared when the schema has a non-empty target namespace; a
chameleon-included global and an imported no-namespace type (via the foreign
pools, checked first) remain accepted.
This corrects an asymmetry where the ref side already rejected the pattern but
the type side did not. The existing SchemaXSIAttributeTests case that asserted
this very pattern compiles used an invalid schema (the same shape as XSTS
addB009/test66059); its type reference is now qualified (tns:attRef), which
preserves the test's xsi:Not-Allowed intent while being valid.
Verified against the full W3C XSTS 2006-11-06 suite: invalid-schemas-accepted
27 -> 25 (addB009/test66059 and one more), valid-schemas-rejected held at 0,
no other bucket moved. Adds a reference test for the type-side rule.
Mihaela Mihaljevic
6e7f1b7bfc