* docs(design): derive the exact Particle Valid (Restriction) procedure
The false-negative tail (particles*/elemZ) routes through one approximate
oracle, ParticleRestriction.violation. Rather than patch cases, derive the
exact XSD 1.0 3.9.6 decision procedure once, clean-room from the spec and the
Xerces reference algorithm, with the soundness (no-false-positive) argument for
each clause: normalization, substitution-group expansion, effective total
range, the compositor dispatch table, and the rcases.
Identifies the closeable gaps (subst-group expansion for elemZ026/V020,
MapAndSum effective-total-range, NameAndTypeOK union-member derivation) and
names the genuine spec limitations (Ha161/Z001 contradiction, mgO013 contested,
union-member by-name derivation) as bounded, not bugs. Sets the implementation
order, each clause gated by the proof plus the XSTS valid-rejected=0 gate and an
adversarial over-rejection critic. No behaviour change.
* docs(design): record the empirical finding -- particle-restriction tail is contested
Probing the actual cases overturned the first hypothesis. elemZ026 and
particlesV020 are the same pattern (a derived ref to a substitution-group
MEMBER restricting a base ref to the HEAD), and PureXML already accepts them
because its content model expands a head ref to admit members (for instance
validation), which the restriction oracle inherits -- the Xerces-lenient
reading. They are CONTESTED (Xerces/PureXML accept, XSTS rejects under strict
NameAndTypeOK), so the keystone (adding expansion) would entrench the
acceptance, not close them; closing them risks a false positive. Every
remaining particle case is contested or FP-delicate, so the exact-oracle
keystone yields no clean conformance win. The remaining lever toward the full
bar is the proven resource bound (pushdown matcher), not this oracle. Proof
first earned its keep: it prevented shipping against contested targets.
Generalise the wildcard {namespace constraint} model to the four XSD 1.0 (with
Errata E1-10) expressible forms -- any; a set (with absent); a pair of not and
a namespace name; a pair of not and absent -- replacing the any/##other/set
model that could not represent the union/intersection results. Both not forms
exclude absent, so a union admitting "every namespace except a name, plus
absent" (E1-10 rule 5.1.3) has no expressible form.
A new SchemaWildcardExpressibility compile rule rejects a complexContent
extension whose attribute-wildcard union with its base is not expressible
(src-ct.5), closing XSTS wildZ013 (test328873i). The expressible unions are
computed exactly in XSDComplexContent, so a derived type's wildcard admits the
correct attributes at instance time, closing wildZ013a and wildZ013d.
invalid-schemas-accepted 12 -> 11, invalid-instances-accepted 17 -> 15, with
valid-schemas-rejected and valid-instances-rejected held at 0 (full XSTS
archive). The model is additive for element wildcards (which never produce the
new forms); admits/narrows/UPA-overlap updated and verified unchanged for the
##other cases.
The intersection of two not forms negating different namespace names is not
expressible (src-ct.4), a deferred rule: rather than drop the wildcard and
over-reject valid cross-namespace attributes on an accepted schema, the
intersection stays the less-restrictive not(lhs) over-approximation (FP-safe,
matching prior behaviour). Union/intersection algebra taken clean-room from
Xerces-J XSWildcardDecl. Guarded by SchemaWildcardUnionExpressibilityTests.
XSD charClassSub ::= (posCharGroup | negCharGroup) '-' charClassExpr is the set
difference of the (possibly negated) group and the subtrahend, so for
[^cde-[ag]] negation applies to the base first and the subtrahend is removed
from that result: the class admits everything except {a, c, d, e, g}.
CharClass.matches applied the subtraction to the positive membership and
negated afterwards, so [^cde-[ag]] excluded only {c, d, e} and wrongly matched
a/g, accepting instance values a correct engine rejects. Negation now applies
to the base before subtraction (new result !B && !S is a strict subset of the
old !B || S, matching the Xerces-J reference exactly), so only negated classes
that also carry a subtraction change behaviour.
Closes XSTS RegexTest_430 and RegexTest_422: invalid-instances-accepted 19 ->
17, valid-instances-rejected and valid-schemas-rejected held at 0 (full XSTS
archive). Guarded by RegexCategoryTests.test_negatedSubtraction.
XSD 1.0 charProp is IsCategory | IsBlock, an exhaustive set: every Unicode
general category plus a fixed Unicode-3.1 block list. The block table was
missing the nine supplementary-plane blocks (Old Italic, Gothic, Deseret, the
Byzantine/Musical/Mathematical symbol blocks, CJK Unified Ideographs Extension
B, CJK Compatibility Ideographs Supplement, Tags) and the three surrogate
blocks, so parseCategory could not tell a real-but-untabulated block from a
bogus name and stayed lenient (RegexError.unsupported), accepting the pattern
\p{IsaA0-a9} and the schema declaring it (XSTS reK88).
Complete the table to the full XSD set: supplementary blocks with their ranges,
and surrogate blocks as valid names whose ranges hold no scalar (so they match
nothing). The recognised set is now authoritative, so parseCategory throws the
rejecting RegexError.invalidProperty for any unrecognised name. The now-dead
RegexError.unsupported case and the isMalformedProperty heuristic are removed.
Closes XSTS reK88: invalid-schemas-accepted 13 -> 12, valid-schemas-rejected
held at 0, instance buckets unchanged (full XSTS archive). Side effect: a
pattern naming a supplementary-plane block (e.g. \p{IsMusicalSymbols}) now
matches its characters instead of failing to compile, removing a latent
instance false positive. Block names/ranges taken from the XSD-supported list
in Xerces-J Token.java (clean-room: factual data only). The list is
spec-frozen at Unicode 3.1, so later blocks are rejected by design.
XSD 1.0 Datatypes Appendix F defines SingleCharNoEsc as [^\[\]] and admits a
nested class only as a -[...] subtraction, so a `[` inside a character class
that is not introduced by `-` is a syntax error. RegexParser treated such a
`[` as a literal scalar, so `[a[:xyz:]` compiled and the schema declaring it
was wrongly accepted (XSTS RegexTest_993, RegexTest_1477).
nextClassMember now throws a dedicated RegexError.unescapedClassBracket, kept
distinct from the generic, deliberately-lenient badClass so the change cannot
regress a valid-but-unsupported pattern. XSDSimpleParser.rejectsPattern treats
it as a genuine syntax error, so the declaring schema is invalid.
Closes RegexTest_993 and RegexTest_1477: invalid-schemas-accepted 15 -> 13,
valid-schemas-rejected held at 0, instance buckets unchanged (full XSTS
archive). Escaped [a\[c] and subtraction [a-z-[aeiou]] stay valid; the
unterminated case [a[:xyz: now faults on the inner [.
The streaming-vs-tree differential previously exercised group references only
through the shallow g0/g1 mutual cycle, too weak to gate a future pushdown
content-model matcher whose call/return correctness hinges on deep group
nesting. Add a deep LINEAR group-reference chain (c0 -> ... -> c{chainDepth},
single ref per level so its inlined size is O(depth), not 2^depth) reachable
from any leaf, so the two engines are compared over deep call/return without the
exponential build a doubling chain would trigger. Run divergence-free over the
standing 2000-seed gate and a 60000-seed campaign.
Reconcile docs/release-hurdles.md Part 2 with the deleted positionCap and record
the one remaining structural residual, distinct from occurrence unrolling: the
per-instance NFA build still inlines group references, so a 2^K-inlining schema
makes automaton construction exponential on first instance validation. Document
the pushdown/RTN matcher as the general fix, gated by this hardened differential
(FP-critical: naive sub-model sharing without a stack is unsound).
The Unique Particle Attribution check no longer inlines group references or caps.
A new CompositionalDeterminism engine computes first/followlast over particle
identities and summarizes each xs:group once, so a multiply-referenced nested
group whose inlined Glushkov automaton would be 2^K positions is checked in
O(nodes * particles^2) time. ContentModelDeterminism now delegates to it and the
inlining position automaton plus positionCap are deleted, closing the last named
interactive-safety resource-bound blocker (production-readiness stopper #4) and
the silent under-rejection the cap caused (stopper #3).
The compositional engine was proven verdict-equivalent to the prior inlining
automaton by a differential over the entire XSTS corpus (zero divergences) before
replacing it. The followlast detail was essential: a first attempt that emitted a
repeating end-item's loop-back and the suffix-first as separate decision sets
under-detected 13 XSTS content models; the differential caught every one.
Verification: XSTS gate unchanged (invalid-schemas-accepted 15, valid-schemas-
rejected 0, instance buckets held); SchemaDeterminismGroupBlowupTests compiles a
2^20-position model without hanging and rejects an ambiguous one the old cap would
have skipped (WASI uses a smaller depth, native time limits gated off WASI); full
suite, style, namespacing, and WASM all pass. The per-particle model and QName-only
overlap are preserved, so the false-positive direction stays at zero.
Turns the 'blocked design frontier' for ContentModelDeterminism.positionCap into
a ready-to-implement, FP-safe plan derived from the current engine. Documents the
root cause (group-ref inlining gives 2^K positions), why naive position
dedup/sharing is unsound (cross-context followpos merge = false positive), the
sound compositional algorithm (per-group memoized nullable/firstParticles/
lastParticles/followlast over particle identities, cross-boundary conflicts
computed per reference-site by the parent, the star condition for repetition,
bounded O(nodes x particles^2)), and the differential-gated rollout (build
alongside the inlining oracle, prove verdict-equality on XSTS + a group-ref fuzz,
only then switch and delete the cap) with acceptance criteria.
cvc-elt.3.1: when an element's declaration is not nillable, the xsi:nil attribute
is forbidden entirely, whatever its value. PureXML only rejected xsi:nil="true" on
a non-nillable element, so xsi:nil="false" slipped through. ComplexValidator.nilErrors
now flags the presence of any xsi:nil on a non-nillable element via the new
nilAttributeValue helper, while a nillable element still accepts xsi:nil="false"
(explicitly not nilled, valid empty-or-content per its type).
XSTS invalid-instances-accepted 28 -> 26 (both xsi:nil-on-non-nillable cases), no
other bucket moved (valid-schemas-rejected and valid-instances-rejected held at 0
across all 14383 groups). 1452 unit tests pass.
XSD 1.0 3.3.2: an element with neither a `type` attribute nor an inline type, but
a `substitutionGroup`, takes the {type definition} of its head. PureXML defaulted
such an element to `anyType`, so an instance of it accepted any content.
`XSDParser.elementType` now resolves the head declaration through
`context.globalElements` (transitively, with a cycle guard) and uses its type.
XSTS invalid-instances-accepted 29 -> 28 (typeDef00204m: <root>Yes</root> is no
longer accepted where root substitutes a boolean head), no other bucket moved
(valid-schemas-rejected and valid-instances-rejected held at 0 across all 14383
groups). 1451 unit tests pass.
cvc-elt.4.3.2.1 requires an xsi:type to name a type DERIVED from the element's
declared type. anyType is the ur-supertype of every type, so it is never derived
from anySimpleType (its own subtype); an anyType override on an anySimpleType
element is therefore invalid. The general not-derived check stays silent on
ur-type declared types to avoid false positives, so this adds the narrow,
provably-invalid anyType-for-anySimpleType pairing only, leaving anyType valid on
an anyType-declared element (which resolves to a complex ur-type and is excluded).
XSTS invalid-instances-accepted 30 -> 29 (stZ056), no other bucket moved
(valid-schemas-rejected and valid-instances-rejected held at 0 across all 14383
groups). 1450 unit tests pass.
XSD 1.0 has no year zero (the year before 0001 is -0001), so 0000-01-01T00:00:00
and the other 0000 forms are not valid values. DateTimeParser.parseYearOnly now
rejects a zero magnitude for both signs, so negative years like -0001 still parse.
Closes the XSTS dateTime011 false negative: invalid-instances-accepted 31 -> 30,
no other bucket moved (valid-schemas-rejected and valid-instances-rejected held at
0). 1449 unit tests pass; the full XSTS suite settles at 0/43/0/30.
The Antigravity onboarding definition-of-done checklist still read
'valid-schemas-rejected still 1'; the enforced baseline is 0
(Tests/XSTSSuiteTests.swift), matching the rest of this file and GEMINI.md.
Caught by the PR review pass.
- README, roadmap: XSTS status quad and gates table now read the enforced
0/43/0/31 (Tests/XSTSSuiteTests.swift); test count 986/169 to 1448/258;
encoding list and the remaining-work section reflect shipped reality;
check-all expansion lists the validation and changelog gates
- GEMINI.md, onboarding-antigravity.md: valid-schemas-rejected 1 to 0 and the
pinned baselines updated to current
- SECURITY.md: complete the reporting address
- Parsing.InputEncoding: doc comment lists the full shipped encoding set
- Schema.XSDParserUnion: guard the localName interpolation with ?? "" to match
the same line and silence an optional-interpolation warning (internal dedup
key, behavior preserving)
- CHANGELOG: Unreleased entries for the above
Companion to production-readiness.md and roadmap.md. Characterizes, with code
evidence, the two biggest hurdles. (1) The invalid-accepted tail concentrates in
ParticleRestriction.violation's deliberately under-approximated clauses (MapAndSum,
RecurseAsIfGroup, NameAndTypeOK): a single high-fan-in oracle where tightening
risks a false positive. (2) ContentMatcher unrolls occurrence values into NFA
states, so the occursUnrollCap/totalStateCap/positionCap caps are band-aids that
silently degrade to star; a counting automaton is what turns the cap into a proven
bound.
Make public/rules-swift the canonical source (per project direction) and adopt
its opt-in lint rules that PureXML lacked: empty_count, explicit_init, first_where,
sorted_first_last, unused_import, plus its todo disable. All pass with zero
violations on the existing sources.
PureXML keeps its coherent, stricter tuning where the canon is a self-described
'starting point': force_unwrapping/force_try/force_cast = error (safety), and
trailing commas mandated in both swiftformat (--commas always) and swiftlint
(mandatory_comma) to resolve the canon's formatter-adds vs linter-flags mismatch.
docs/rules/README.md now points at public/rules-swift and documents the tuning.
Adds a dated accounting to the XSTS deviation worklist: the labelled-suite
ratchet stands at 0/74/0/133 with false positives held at 0 across the campaign.
Partitions the remaining 74 into fixable-but-intricate debt (redefine
restriction, NameAndTypeOK union membership, wildcard UPA, chameleon/cross-ns
composition, heterogeneous particle edges) and irreducible-by-design or disclosed
items (RecurseAsIfGroup spec ambiguities, the deliberate regex-tolerance), with
the root cause and false-positive risk for each so the burndown is driven by
understanding. Records that the adversarial critic loop caught three genuine
false positives this session that the suite and differential both missed.
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.
Ship the OpenAPIKit-style validation layer (builtin rules, warnings channel,
Validator tiers, coverage gates) and wire XSD compile checks through it. Advance
#161 with chameleon include validation, multi-container reference resolution,
and include targetNamespace composition rules so merged schema sets compile
correctly when a schemaLoader is provided.
Document the restructured GitHub issue hierarchy (epic #167, gates,
milestones M1-M5, task labels) and point README Status at the current
production-readiness focus and v0.2.0 XSTS baselines.
Cut the second pre-release: schema-validity burn-down to XSTS baselines
1/266/171/155, component child-content shape checks, and synced conformance
docs. CHANGELOG updated for v0.2.0.
Require that any restricted attribute has a type validly derived by restriction from its base counterpart. Validates atomic built-in derivation, list item type restrictions, and union member/subset relationships recursively. Updates baseline to 362 accepted invalid schemas.
Reject top level declarations that omit a name attribute. Disallow derivation by restriction of xs:anySimpleType inside simpleType definitions. Require restriction facets length, minLength, maxLength, totalDigits, and fractionDigits to restrict or equal the base type facets. Updates the conformance baseline to 383 accepted invalid schemas.
