The instance-validity derivation and substitution tables were keyed by bare
local name, so two same-local-name types or elements in different namespaces
collided. In multi-document validation this let one schema's block/derivation
facts shadow another's, and it blocked honouring blockDefault (whose re-land
widened that collision into an over-rejection).
Key the instance subsystem by namespaced identity {ns}local instead. The shared
DerivationTables keeps its bare-keyed fields for the schema-validity machinery
(Particle-Valid-Restriction and the consistency rules, which resolve QNames to
bare names and walk the same backbone) and gains parallel ns* fields built in
the same pass, resolving each container's components through its target
namespace and prefix bindings. Only the instance consumers
(blockedSubstitutionError, notDerivedSubstitutionError, abstractTypeError, the
substitution-group closure, and referenceParticle) read the ns* tables, via a
derivationKey(fromReference:) that reduces a type:{ns}local reference, a bare
name, or an element ref to a {ns}local backbone key. A key miss stays permissive
(no constraint, substitution allowed), so the re-keying cannot over-reject.
With the namespaced backbone in place, blockDefault is re-landed FP-free: a
schema's blockDefault supplies the {disallowed substitutions} of every element
and complex type without an explicit block (own block overrides; block="" clears;
intersected with the methods each component admits), so blockDefault="extension"
bars an extension substitution and "#all" bars all, without one namespace's
defaults shadowing another's.
The pure re-keying preserves single-document behaviour exactly (the corpus is
overwhelmingly single-namespace, where {ns}local and bare coincide): all four
XSTS buckets held at vsr=0 / isa=69 / vir=0 / ivi=89 after re-keying alone.
blockDefault then drove invalid-instances-accepted 89 to 81, no false positive
(valid-instances-rejected and valid-schemas-rejected held at 0), no other bucket
moved. An adversarial review exercised same- and cross-namespace substitutions,
no-targetNamespace keys, simple-type restriction, transitive substitution groups,
and blockDefault override/over-block cases, and the prior multi-document
cross-namespace blockDefault over-rejection is now accepted while a same-namespace
blocked substitution is still rejected (precise, not merely permissive).
A restricting element may not be nillable unless the base element it restricts
is also nillable. The element particle (Term.element) now carries a nillable
flag, populated from the element's nillable attribute.
XSTS invalid-schemas-accepted 144 to 142, no other bucket moved.
Particle Valid (Restriction) now requires a restricting element's {disallowed
substitutions} to be a superset of the base element's: a restriction may block
more substitutions, never fewer. The element particle (Term.element) carries a
block set, populated from the element's block attribute or the schema's
blockDefault.
XSTS invalid-schemas-accepted 179 to 163, no other bucket moved.
Consolidates the in-progress #146 work; valid-instances-rejected reaches 4
on the 2006-11-06 XSTS archive (buckets now 1/262/4/147).
Regex: match Unicode scalars rather than grapheme clusters; the empty
pattern matches only the empty string; pin the category repertoire to
Unicode 3.2, the version the corpus is consistent at, so code points added
in 3.2 (Tagalog, Cyrillic Komi) are word characters while later additions
(the Tamil digit zero) stay unassigned and match \D. New XSDCategory and a
3.2 assignment table derived from DerivedAge, replacing the old Unicode31
files.
Content model: assess each child against the particle the content automaton
matched, not a by-name lookup (#180). Two same-named particles keep their
own fixed values, and an element matching a skip wildcard is no longer
validated against its global declaration. Selection is made reproducible
when an ambiguous schema slips past the UPA check.
XSTS runner: compile and merge every schemaDocument in a schemaTest, not
just the first; this also surfaced one previously-masked invalid-instance
acceptance (recorded in the baselines).
Also folds in attribute-group anyAttribute inheritance, extension wildcard
union, namespace-qualified type tables for multi-document
xsi:schemaLocation, per-container elementFormDefault, strict and lax
attribute wildcard validation, built-in type resolution, and xs:redefine
simpleType overrides.
