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.
