The two monolithic XSD content/identity rules only satisfied the OpenAPIKit
validation idiom at the wrong granularity: no per-constraint removability,
no isolable failing/near-miss tests. Split them into 32 named rules, each
finding tagged at its origin and cached per XSDContext so the walk still
runs once per document (the #101 decision against duplicating XSD's
recursive type resolution still holds). Wired the streaming path's ID/IDREF
and identity checks through the same framework instead of calling the
validators imperatively, and added the unwrapAndLookup combinator the rule
already named as required.
Also includes the mandated repo-wide swiftformat/swiftlint pass.
Keep the reader on its byte fast path through dispatch and name/attribute
scanning so plain-ASCII documents avoid the per-Character String machinery
(String.Iterator.next, string comparison, small-string materialization,
bridge-object ARC) that a profile indicted as the parse bottleneck.
The root cause was that a single buffered lookahead Character defeated every
existing byte path, each of which requires an empty buffer, and the content,
markup, and attribute dispatch each peeked a Character before scanning. Add a
non-buffering peekByte for dispatch, a byte-mode skipSpace, an all-ASCII
takeASCIIName, and an attributeRunBytes bulk scanner (with the 3.3.3
whitespace-to-space transform, deferring any carriage return to the Character
path so CRLF is not double-counted). Detect a text run's closing '<' via
peekByte instead of buffering it, which had cascaded the next element's whole
dispatch and name scan onto the slow path. Skip reference decoding for
ampersand-free text. The Character path remains the exact fallback for a
streaming source, spliced entity text, and any non-ASCII byte; the two paths
share scanContentMarkup so they cannot diverge.
Measured parse 20.1x -> 9.5x slower than libxml2 on the 20k-item generated
corpus, roughly a 53 percent wall-clock reduction. A differential oracle pins
the byte and Character paths to identical event streams and error marks over
an adversarial corpus, alongside boundary tests. Verified against the full
local suite, the Apache Xalan XSLT gold-output corpus, the W3C XML conformance
corpora, the RELAX NG spec suite, and the WASM build. No spec behavior changed.
Complete the DTD attribute handling found in the audit:
- Default and #FIXED attribute values are applied to the parsed tree.
parseApplyingInternalDTDDefaults returns a tree where every element
carries the attributes its <!ATTLIST> defaults, so an editor sees the
same effective attributes a validating processor would.
- NMTOKEN, NMTOKENS, ENTITY, ENTITIES are validated: NMTOKEN(S) must be
XML name tokens, ENTITY/ENTITIES must be XML names. Previously all fell
through to unconstrained CDATA.
- DTD default values are normalized per XML 1.0: character and predefined
entity references are expanded, literal whitespace becomes a space, and
non-CDATA values are collapsed and trimmed.
ENTITY/ENTITIES check name syntax only; that the named entity is a
declared unparsed entity is not verified, since NDATA entity tracking is
not yet modeled.
Closes#73
Add PureXML.Parsing.XMLCharacter as the single source of truth for character
classes, implementing the exact XML 1.0 (Fifth Edition) Char, NameStartChar, and
NameChar productions as public scalar predicates, plus isValidName. The scanner's
name recognition now delegates to these exact ranges (replacing a loose isLetter
check) and handles precomposed and combining-mark names. Closes#35.
Reimplemented from the XML grammar; no upstream code copied. 4 tests; 98 total.