parseTree ran TreeNode(parse(...)), which allocates two full trees: the parser
builds an immutable value Node tree, then TreeNode.init(_:) walks it to build
the mutable reference tree. The parsed tree is the deliverable, so building the
value tree first is pure overhead.
Parser.buildTree is the direct counterpart to build: the same iterative event
loop with the same element stack and the same well-formedness guards (an
unmatched end tag throws unexpectedEndOfInput; a document with no element throws
emptyDocument), but it accumulates TreeNode children per frame and adopts them
when an element closes, so the tree is allocated once. The produced tree is
identical: same kinds, names, attributes, values, child order, and parent links.
Measured parse ~8% faster on the 20k-item generated corpus via a same-state A/B
(6.1x to ~5.5x slower than libxml2). Verified by ParseTreeDirectBuildTests (a
structural differential against the convert-from-Node path, plus throw-parity
and a serialized round-trip), the full suite and the W3C XML conformance,
RELAX NG, and Xalan corpora (which all build trees through parseTree), the WASM
build, and an adversarial equivalence review.
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.
The scanner records declaration provenance (internal-subset entities,
element models, attribute lists); the validator reports the three
standalone='yes' dependencies on the external subset: a default that
would be supplied, a non-CDATA normalization that would change a value,
and whitespace in externally-declared element content. The parser hides
externally-declared entities from standalone documents, so referencing
one reports as undeclared (WFC: Entity Declared, 2.9). The Sun section
is fully clean: not-wf 56/56, valid 28/28, invalid 74/74, no baseline.
Closes#134Closes#124
Document the weak-parent ownership trap at the public entry points: parseTree
and readTree now state that a tree (or ownerDocument) must be held while using
any node inside it, that TreeNode has no internal synchronization (confine to
one thread or actor), and that the immutable Sendable Node projection is the
way across concurrency boundaries; the TreeNode class doc carries the same
contract. QualifiedName's malformed-colon fallback (':local', 'prefix:', '::'
stay whole and unprefixed), already implemented, is now documented on init
and locked by a test.
Closes#114
Add PureXML.Parsing.ByteEncoder, the inverse of ByteDecoder, and a
Serializer.serialize(_:encoding:) / PureXML.serialize(_:encoding:) that
emits bytes in a chosen encoding (the libxml2 save-with-encoding model).
Covers the Unicode transformation formats and the single-byte legacy
families, built by inverting the existing vendored to-Unicode tables, so
no new data is introduced. The declaration carries the canonical encoding
name, a UTF-16/32 stream is preceded by a byte-order mark, and any
unrepresentable scalar becomes a decimal numeric character reference, so
output round-trips. CJK output encodings remain (tracked on #106).
Part of #106, #105
Parse the XML declaration's pseudo-attributes instead of skipping the
<?xml?> processing instruction:
- version, encoding, and standalone are surfaced on a new XMLDeclaration,
returned from parseWithDocumentType and via PureXML.xmlDeclaration(_:).
- The pseudo-attributes are validated: fixed order (version, encoding,
standalone), known names only, and standalone must be yes or no. A
malformed declaration is rejected.
- The declared version is now readable, a prerequisite for XML 1.1.
parseWithDocumentType returns a ParsedDocument struct (node,
documentType, declaration) rather than a 2-tuple; the member names are
unchanged so existing call sites are unaffected.
Closes#95
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
Slice 1 of #94 (editor integration). The keystone: a located validation finding
can now be mapped back to a source range.
- TreeNode gains a sourceRange (start/end Mark); SourceRange is a half-open span.
- PureXML.readTree builds a mutable, parent-aware, best-effort tree whose every
node carries its span (an element from the < of its start tag to past its end
tag; leaves over the text they consumed). Never throws, recovers in place,
returns located diagnostics.
- TreeNode.node(at:) navigates a validation coding path to its node using the
same canonical convention the validators build paths with (a sibling index
only when a name repeats), and sourceRange(at:) returns the span. So
Document.validate's ValidationError.codingPath resolves to characters in the
document.
Tests prove the spans, the navigation, the end-to-end bridge (an XSD finding to
a source range), and that ranged reading of invalid input never crashes.
Slice 3 of #92. The DTD validator's imperative walk becomes declared Validation
values over a DTDSchema document:
- DTDSchema is now just the schema (content models + attribute declarations) and
serves as the rules' Document context; its validate/walk methods are gone.
- contentModel and attributeDeclarations are Validation<Element, DTDSchema>, so
every content-model and attribute violation is now located by coding path
("... at path: r/a"). undeclaredElement is added only in strict mode.
- identifierIntegrity is a Validation<Node, DTDSchema> gated to the root, doing
the document-wide ID-uniqueness and IDREF-resolution checks in one pass.
- DTD.validator(strict:) assembles the rule set; validateAgainstInternalDTD runs
it and returns [ValidationError] instead of [Issue].
A new test pins the located result. Schema (XSD) and Schematron validators still
use Issue and migrate in the following slices.
Slice 2 of #92. Add PureXML.read, a deterministic recovering reader: it never
throws and never traps, returning the maximal best-effort tree plus one located
Diagnostic per problem.
- ReadResult { node, diagnostics } is the Equatable result type, so a
deterministic read can be compared whole.
- Diagnostic carries a message and a structured source Mark; a thrown ParseError
maps to one directly (ParseError.mark exposes the position each case carries).
- The reader resynchronizes after a failure (EventReader.recover(from:)):
progress-aware, so a failure that already consumed the bad construct retries
from there, while a stuck failure skips to the next markup start; it always
advances when input remains, guaranteeing termination.
- The tree builder assembles leniently: elements left open by truncation are
closed, an end tag with no open element is dropped. Well-formed input yields
exactly parse(_:)'s tree with no diagnostics.
Tests pin exact trees and diagnostics for truncation, mismatched tags, and stray
junk, prove determinism (same bytes give an identical ReadResult), and fuzz 400
seeded inputs (arbitrary plus truncated valid docs) asserting no crash.
Recovery here is resync-based; finer in-reader recovery (keep the element on a
duplicate attribute, pop to a matching open tag) is the next slice.
Slice 1 of #92. Introduce the OpenAPIKit-idiom validation framework, replacing
the imperative if-tree structural validator:
- ValidationError (reason + coding path) renders "<reason> at path: root/row/cell";
ValidationErrorCollection gathers every failure and is thrown once.
- Validation<Subject, Document> is the atomic, composable rule value, with the
multi-error and single-error Bool inits (the latter auto-forms "Failed to
satisfy: <description>"). Predicate-gated, type-directed via an erased
AnyValidation that guards an optional from matching a non-optional rule.
- The framework is parameterized over both Subject and Document so the structural,
DTD, XSD, and Schematron layers share one machinery (Document = Void for rules
that need only their subject).
- Validator<Document> walks the node tree, building the coding path, with blank /
default factories and fluent validating / withoutValidating.
- The combinator algebra (&&, ||, comparison lifts, take, lift, unwrap, all) as
free functions returning closures.
The structural duplicate-attribute rule is reborn as Validation<Element, Void>.
Combinators and the erased wrapper are unit-tested as pure functions per the rule.
The legacy Validation.Issue stays only for the not-yet-migrated schema validators
and is retired in a later slice.
Replace monolithic ci.yml with per-platform workflows so each README badge
tracks one job. Scan commit messages for tool-agnostic AI attribution in CI,
sync local hooks to the canon, and refresh README status plus git-discipline Rule 8.
Add PureXML.Parsing.TextReader (via PureXML.reader), a pull cursor over the
streaming core. read() advances node by node, exposing nodeKind, name,
value, depth, attributes, and isEmptyElement. A childless element is
reported once as an empty element, normalizing <a/> and <a></a>. The
documentType accessor surfaces the DTD read so far as the validation hook.
Closes#33
Add PureXML.Model.TreeNode, a reference-type document tree that knows its
parent and siblings. Navigation goes up and sideways (parent, nextSibling,
previousSibling, ancestors, root, elementChildren, stringValue) and editing
is in place (append, insert before/after, removeFromParent, replace, copy).
Children are held strongly and the parent weakly; attaching a node detaches
it from any prior parent and a node can never become its own ancestor.
parseTree builds one from XML; TreeNode.node converts back for serialization.
Closes#31
Add internal parameter entities (parsed, stored, and expanded within the
DTD, including bare %name; references that inject markup declarations,
bounded by depth and the expansion budget). Record external general
entities and the external subset identifier, and load them only through an
injected EntityResolver (a struct of closures). The default refusing
resolver fetches nothing, so XXE stays closed: an external entity fails as
undefined and the external subset is left unread. Internal declarations win
over the external subset.
Closes#29
Add PureXML.Parsing.SAXHandler (a struct of optional callbacks) and
PureXML.parse(_:sax:), which drives the handler from the streaming event core,
delivering start/end document, start/end element, characters, CDATA, comment,
and processing-instruction callbacks. Element names are namespace-resolved.
Closes the SAX2 epic (#19). Reimplemented from the libxml2 SAX2 model; no
upstream code copied. 5 tests; 84 total.
Surface <!ATTLIST> declarations from the parser and validate attributes against
them. Reimplemented from the DTD attribute-list spec; no upstream code copied.
- DocumentType gains attributeLists (raw ATTLIST bodies per element); the
DoctypeScanner captures them and the EventReader plumbs them through.
- AttributeListParser parses a body into AttributeDeclaration values
(AttributeType: cdata or enumeration; AttributeDefault: required/implied/
fixed/value).
- DTDSchema now checks #REQUIRED presence, #FIXED value match (when present),
and enumerated-value membership, in addition to content models.
- Tokenized types (ID/IDREF/NMTOKEN) parse but are not yet value-enforced.
- 5 attribute tests; 75 total.
Surface the parsed <!DOCTYPE> internal subset's <!ELEMENT> declarations from the
parser and validate a tree against them. Reimplemented from the DTD content-model
spec; no upstream code copied.
- DoctypeScanner captures <!ELEMENT name model> declarations; the parser surfaces
them as Parsing.DocumentType (via parseWithDocumentType).
- Validation.ContentModel + ContentModelParser parse a model string (EMPTY, ANY,
(#PCDATA), mixed, and element content with sequence/choice and ?/*/+).
- ContentModelMatcher matches the child element-name sequence against a model as
a regular language (NFA-position matching).
- Validation.DTDSchema.validate reports issues for EMPTY/PCDATA/mixed violations,
element content with stray text, and child sequences that do not match.
- PureXML.validateAgainstInternalDTD(_:) parses and validates in one call.
- ATTLIST validation is out of scope. 9 tests; 70 total.
Add PureXML.XPath: a compiled location-path query engine reimplemented from the
XPath 1.0 specification; no upstream code copied.
- Compiler parses a path into steps; Evaluator walks the tree returning a
Selection node-set (node or attribute) in document order.
- Forward axes only (child, descendant //, self ., attribute @), since the value
model has no parent pointers. Node tests: name, *, text(), node(), comment().
Predicates: [n], [@a], [@a='v'], [child], [child='v'].
- Public surface: XPath.Query (init compiles, evaluate/elements/strings), the
Selection enum (element / stringValue), QueryError, and the one-shot
PureXML.xpath(_:over:). Upward/sibling axes and the full expression language
are explicitly out of scope.
- 12 XPath tests; 61 total.
Add PureXML.parse(pullingBytes:) and events(pullingBytes:) over an incremental
byte source (() -> UInt8?). StreamingDecoder detects the encoding from the
leading bytes, strips any BOM, and yields one scalar at a time as a Character,
so a byte stream is never fully buffered. UTF-8 (1 to 4 bytes) and UTF-16 (with
surrogate pairs) are decoded incrementally; invalid sequences become the Unicode
replacement character. Standard library only, no Foundation. Reimplemented from
the documented UTF decoding rules; no upstream code copied.
Add PureXML.parse(bytes:) and events(bytes:) for raw [UInt8] input. The encoding
is detected following the XML sniff order (BOM first, then the <? byte pattern,
defaulting to UTF-8) and decoded with the Swift standard library only, so the
package stays Foundation-free and portable. UTF-8 and UTF-16 (both byte orders,
with or without a BOM) are supported, the encoding set the XML spec requires.
Malformed input (odd-length UTF-16) raises ParseError.malformedEncoding.
PureXML.Parsing.InputEncoding.detect(_:) exposes the detector. The lint rule
optional_data_string_conversion is disabled because its suggested fix is a
Foundation API this package cannot use. Reimplemented from the documented XML
byte-detection algorithm; no upstream code copied.
Add PureXML.Parsing.Limits: configurable caps on nesting depth (default 256,
matching libxml2), name length, and content length, enforced during scanning in
the event reader. This protects against pathological input (deeply nested or
oversized documents) and keeps the recursive Model.Node value safe to build and
tear down (extreme depth otherwise overflows on ARC release). Threaded through
Parser.parse and the top-level parse/events API. Reimplemented from libxml2's
bounded-by-default posture; no upstream code copied.
Replace the notImplemented stub with a real parser built on a pull-based,
streaming event core that never requires the whole document in memory.
- Parsing.EventReader: pulls characters through a source closure with a bounded
lookahead buffer and emits one Parsing.Event at a time, holding only an
open-element stack. Drives chunked/streamed input.
- Parsing.Parser: builds a Model.Node tree iteratively over the event core
(explicit stack, no recursion).
- Reader: streaming character cursor (closure-backed, bounded buffer) replacing
the previous whole-string Array.
- EntityDecoder: the five predefined entities and decimal/hex char references.
- Handles elements, attributes, text, comments, CDATA, processing instructions,
and an XML declaration in the prolog. Rejects <!DOCTYPE> by default (no
DTD/XXE/entity-expansion exposure).
- Top-level API: parse(_:), parse(pulling:), events(_:), events(pulling:).
- 21 tests including event-stream and chunked-source coverage.
Root Swift package mirroring PureYAML's structure, rules, and verification
gates. Includes the XML node model (Node, Element, Attribute, QualifiedName),
a working emitter (Serializer) with escaping and pretty/compact options, and
structural validation. The parser surface is stable; parse() raises
notImplemented until the scanner lands, pinned by a test.
- dependency-free, namespaced under PureXML
- portability and style gates carried over (style, namespacing, forbidden
patterns, swiftformat, swiftlint, linux, wasm, windows CI)
- 11 tests passing
