AE13b5: add deterministic parser snapshot serializers

crates/html/src/conformance/execution.rs

@@ -26,6 +26,167 @@ pub enum ObservationRequest {
     },
 }
 
+#[cfg(test)]
+mod execution_identity_tests {
+    use super::*;
+
+    #[test]
+    fn every_closed_parser_observation_error_identity_is_preserved_without_text_classification() {
+        for (error, identity) in [
+            (
+                ParserObservationExecutionError::ParserInvariant,
+                ParserObservationExecutionIdentity::ParserInvariant,
+            ),
+            (
+                ParserObservationExecutionError::TokenCanonicalizationInvariant,
+                ParserObservationExecutionIdentity::TokenCanonicalizationInvariant,
+            ),
+            (
+                ParserObservationExecutionError::TreeTransitionTokenCanonicalizationInvariant,
+                ParserObservationExecutionIdentity::TreeTransitionTokenCanonicalizationInvariant,
+            ),
+            (
+                ParserObservationExecutionError::ObservationRecorderMissing,
+                ParserObservationExecutionIdentity::ObservationRecorderMissing,
+            ),
+            (
+                ParserObservationExecutionError::PatchHistoryCaptureMissing,
+                ParserObservationExecutionIdentity::PatchHistoryCaptureMissing,
+            ),
+        ] {
+            assert_eq!(error.identity(), identity);
+        }
+
+        assert_eq!(
+            ParserObservationExecutionError::ParserFatal(crate::ParserFatalError::EngineInvariant)
+                .identity(),
+            ParserObservationExecutionIdentity::ParserFatal(ParserFatalIdentity::EngineInvariant),
+        );
+        for (site, identity) in [
+            (
+                crate::ParserReservationSite::KnownTagAtomStorage,
+                ParserReservationSiteIdentity::KnownTagAtomStorage,
+            ),
+            (
+                crate::ParserReservationSite::KnownTagLookupStorage,
+                ParserReservationSiteIdentity::KnownTagLookupStorage,
+            ),
+            (
+                crate::ParserReservationSite::TemplateChildStorage,
+                ParserReservationSiteIdentity::TemplateChildStorage,
+            ),
+            (
+                crate::ParserReservationSite::PatchHistoryObservationStorage,
+                ParserReservationSiteIdentity::PatchHistoryObservationStorage,
+            ),
+        ] {
+            let error = crate::ParserResourceExhaustion::at(site);
+            assert_eq!(
+                ParserObservationExecutionError::ParserFatal(error.into()).identity(),
+                ParserObservationExecutionIdentity::ParserFatal(
+                    ParserFatalIdentity::ResourceExhaustion(identity)
+                )
+            );
+        }
+
+        for code in [
+            ParserTokenizerInvariantError::SelfClosingFlagMissingSolidusPosition,
+            ParserTokenizerInvariantError::SolidusPositionWithoutPendingTag,
+            ParserTokenizerInvariantError::SolidusPositionOutsideCurrentPendingTag,
+            ParserTokenizerInvariantError::SolidusPositionDoesNotReferenceConsumedSlash,
+            ParserTokenizerInvariantError::DoctypeNameStartMissingForNameState,
+            ParserTokenizerInvariantError::DoctypeNameStartMissingForTailScan,
+            ParserTokenizerInvariantError::DoctypeNameStartMissingForResourceObservation,
+            ParserTokenizerInvariantError::DoctypeNameStartAfterCursor,
+            ParserTokenizerInvariantError::DoctypeNameRangeInvalid,
+            ParserTokenizerInvariantError::DoctypeTailRangeInvalid,
+            ParserTokenizerInvariantError::AsciiPrefixCandidateRangeInvalid,
+            ParserTokenizerInvariantError::CommentStateMissingPendingStart,
+            ParserTokenizerInvariantError::CommentPendingRangeInvalid,
+            ParserTokenizerInvariantError::CommentPendingDelimiterOutsideCurrentRange,
+            ParserTokenizerInvariantError::CommentPendingDelimiterDoesNotMatchState,
+            ParserTokenizerInvariantError::TextModeEndTagCandidateRangeInvalid,
+            ParserTokenizerInvariantError::TextModeEndTagAttributePositionInvalid,
+            ParserTokenizerInvariantError::TextModeEndTagSolidusPositionInvalid,
+            ParserTokenizerInvariantError::PendingTextRangeInvalid,
+            ParserTokenizerInvariantError::CdataStateMissingPendingTextStart,
+            ParserTokenizerInvariantError::CdataEndDelimiterOutsidePendingTextRange,
+            ParserTokenizerInvariantError::CdataEndDelimiterDoesNotMatchState,
+            ParserTokenizerInvariantError::ProcessingInstructionStateMissingPendingMetadata,
+            ParserTokenizerInvariantError::ProcessingInstructionMetadataOutsideState,
+            ParserTokenizerInvariantError::ProcessingInstructionTargetRangeInvalid,
+            ParserTokenizerInvariantError::ProcessingInstructionDataRangeInvalid,
+            ParserTokenizerInvariantError::ProcessingInstructionTargetStartAfterCursor,
+            ParserTokenizerInvariantError::ProcessingInstructionDataStartAfterCursor,
+        ] {
+            assert_eq!(
+                ParserObservationExecutionError::TokenizerInvariant(code).identity(),
+                ParserObservationExecutionIdentity::TokenizerInvariant(code)
+            );
+        }
+
+        for code in [
+            UnsupportedFeatureObservationInvariantError::TokenAttributeNameUnavailable,
+            UnsupportedFeatureObservationInvariantError::ExistingHtmlElementSemanticsUnavailable,
+            UnsupportedFeatureObservationInvariantError::ExistingBodyElementSemanticsUnavailable,
+            UnsupportedFeatureObservationInvariantError::ExistingElementIdentityContradiction,
+        ] {
+            assert_eq!(
+                ParserObservationExecutionError::UnsupportedFeatureObservationInvariant(code)
+                    .identity(),
+                ParserObservationExecutionIdentity::UnsupportedFeatureObservationInvariant(code)
+            );
+        }
+
+        for code in [
+            ParserObservationInvariantError::ParseErrorOccurrenceOverflow,
+            ParserObservationInvariantError::ImplementationDiagnosticOccurrenceOverflow,
+            ParserObservationInvariantError::TreeTransitionOccurrenceOverflow,
+            ParserObservationInvariantError::UnsupportedFeatureOccurrenceOverflow,
+            ParserObservationInvariantError::TokenDroppedCountOverflow,
+            ParserObservationInvariantError::ParseErrorDroppedCountOverflow,
+            ParserObservationInvariantError::ImplementationDiagnosticDroppedCountOverflow,
+            ParserObservationInvariantError::TreeTransitionDroppedCountOverflow,
+            ParserObservationInvariantError::UnsupportedFeatureDroppedCountOverflow,
+            ParserObservationInvariantError::NormalizedPositionOverflow,
+            ParserObservationInvariantError::NormalizedPositionIndexDiscontinuity,
+            ParserObservationInvariantError::NormalizedPositionIndexMissing,
+            ParserObservationInvariantError::InvalidNormalizedPositionOffset,
+            ParserObservationInvariantError::PatchDroppedCountOverflow,
+            ParserObservationInvariantError::CanonicalTreeUnitCountOverflow,
+            ParserObservationInvariantError::CanonicalTreeRootNotDocument,
+            ParserObservationInvariantError::UnexpectedLegacyDocumentDoctypeMetadata,
+            ParserObservationInvariantError::MissingHtmlTemplateContents,
+            ParserObservationInvariantError::InvalidTemplateContentsKind,
+            ParserObservationInvariantError::CanonicalTreeTraversalContradiction,
+            ParserObservationInvariantError::CanonicalTreePreflightProjectionMismatch,
+            ParserObservationInvariantError::InvalidPatchKey,
+            ParserObservationInvariantError::DuplicatePatchCreation,
+            ParserObservationInvariantError::MissingPatchCreationHistory,
+            ParserObservationInvariantError::SnapshotLabelSequenceOverflow,
+        ] {
+            assert_eq!(
+                ParserObservationExecutionError::ObservationInvariant(code).identity(),
+                ParserObservationExecutionIdentity::ObservationInvariant(code)
+            );
+        }
+
+        for site in [
+            ObservationReservationSite::CanonicalTreeProjection,
+            ObservationReservationSite::CanonicalPatchProjection,
+            ObservationReservationSite::SnapshotLabelStorage,
+        ] {
+            assert_eq!(
+                ParserObservationExecutionError::ResourceExhaustion(
+                    ObservationResourceExhaustion::at(site)
+                )
+                .identity(),
+                ParserObservationExecutionIdentity::ResourceExhaustion(site)
+            );
+        }
+    }
+}
+
 #[derive(Clone, Copy, Debug, Default, PartialEq, Eq)]
 pub enum ScalarObservationRequest {
     #[default]
@@ -82,6 +243,104 @@ pub enum ParserObservationExecutionError {
     ResourceExhaustion(ObservationResourceExhaustion),
 }
 
+/// Closed, message-independent identity for fixture disposition matching.
+///
+/// `ParserFatalError` and its reservation site are deliberately non-exhaustive
+/// at the ordinary parser API boundary. Canonical test support therefore asks
+/// the owning HTML subsystem for this feature-gated identity instead of
+/// classifying `Display` or `Debug` text.
+#[derive(Clone, Copy, Debug, PartialEq, Eq)]
+pub enum ParserObservationExecutionIdentity {
+    ParserFatal(ParserFatalIdentity),
+    ParserInvariant,
+    TokenizerInvariant(ParserTokenizerInvariantError),
+    TokenCanonicalizationInvariant,
+    TreeTransitionTokenCanonicalizationInvariant,
+    UnsupportedFeatureObservationInvariant(UnsupportedFeatureObservationInvariantError),
+    ObservationRecorderMissing,
+    PatchHistoryCaptureMissing,
+    ObservationInvariant(ParserObservationInvariantError),
+    ResourceExhaustion(ObservationReservationSite),
+}
+
+#[derive(Clone, Copy, Debug, PartialEq, Eq)]
+pub enum ParserFatalIdentity {
+    EngineInvariant,
+    ResourceExhaustion(ParserReservationSiteIdentity),
+}
+
+#[derive(Clone, Copy, Debug, PartialEq, Eq)]
+pub enum ParserReservationSiteIdentity {
+    KnownTagAtomStorage,
+    KnownTagLookupStorage,
+    TemplateChildStorage,
+    PatchHistoryObservationStorage,
+}
+
+impl ParserObservationExecutionError {
+    #[must_use]
+    pub const fn identity(self) -> ParserObservationExecutionIdentity {
+        match self {
+            Self::ParserFatal(error) => {
+                ParserObservationExecutionIdentity::ParserFatal(parser_fatal_identity(error))
+            }
+            Self::ParserInvariant => ParserObservationExecutionIdentity::ParserInvariant,
+            Self::TokenizerInvariant(error) => {
+                ParserObservationExecutionIdentity::TokenizerInvariant(error)
+            }
+            Self::TokenCanonicalizationInvariant => {
+                ParserObservationExecutionIdentity::TokenCanonicalizationInvariant
+            }
+            Self::TreeTransitionTokenCanonicalizationInvariant => {
+                ParserObservationExecutionIdentity::TreeTransitionTokenCanonicalizationInvariant
+            }
+            Self::UnsupportedFeatureObservationInvariant(error) => {
+                ParserObservationExecutionIdentity::UnsupportedFeatureObservationInvariant(error)
+            }
+            Self::ObservationRecorderMissing => {
+                ParserObservationExecutionIdentity::ObservationRecorderMissing
+            }
+            Self::PatchHistoryCaptureMissing => {
+                ParserObservationExecutionIdentity::PatchHistoryCaptureMissing
+            }
+            Self::ObservationInvariant(error) => {
+                ParserObservationExecutionIdentity::ObservationInvariant(error)
+            }
+            Self::ResourceExhaustion(error) => {
+                ParserObservationExecutionIdentity::ResourceExhaustion(error.site())
+            }
+        }
+    }
+}
+
+const fn parser_fatal_identity(error: crate::ParserFatalError) -> ParserFatalIdentity {
+    match error {
+        crate::ParserFatalError::EngineInvariant => ParserFatalIdentity::EngineInvariant,
+        crate::ParserFatalError::ResourceExhaustion(error) => {
+            ParserFatalIdentity::ResourceExhaustion(parser_reservation_site_identity(error.site()))
+        }
+    }
+}
+
+const fn parser_reservation_site_identity(
+    site: crate::ParserReservationSite,
+) -> ParserReservationSiteIdentity {
+    match site {
+        crate::ParserReservationSite::KnownTagAtomStorage => {
+            ParserReservationSiteIdentity::KnownTagAtomStorage
+        }
+        crate::ParserReservationSite::KnownTagLookupStorage => {
+            ParserReservationSiteIdentity::KnownTagLookupStorage
+        }
+        crate::ParserReservationSite::TemplateChildStorage => {
+            ParserReservationSiteIdentity::TemplateChildStorage
+        }
+        crate::ParserReservationSite::PatchHistoryObservationStorage => {
+            ParserReservationSiteIdentity::PatchHistoryObservationStorage
+        }
+    }
+}
+
 /// Fallible allocation boundary owned by post-parse canonical observation.
 #[derive(Clone, Copy, Debug, PartialEq, Eq, Hash)]
 pub enum ObservationReservationSite {

crates/html/src/conformance/mod.rs

@@ -24,8 +24,9 @@ pub use crate::html5::shared::{
 };
 pub use execution::{
     ObservationRequest, ObservationReservationSite, ObservationResourceExhaustion,
-    ParserObservationExecutionError, ParserObservationInput, ParserObservationInvariantError,
-    ParserObservationRequest, ParserObservationTarget, ParserTokenizerInvariantError,
+    ParserFatalIdentity, ParserObservationExecutionError, ParserObservationExecutionIdentity,
+    ParserObservationInput, ParserObservationInvariantError, ParserObservationRequest,
+    ParserObservationTarget, ParserReservationSiteIdentity, ParserTokenizerInvariantError,
     ScalarObservationRequest, UnsupportedFeatureObservationInvariantError,
     execute_parser_observation,
 };

crates/html/tests/fixtures/html5/conformance/README.md

@@ -1,6 +1,6 @@
 # Canonical HTML Parser Conformance Fixtures
 
-This is the native fixture root for `borrowser-html-parser-fixture-v1`. Discovery
+This is the native fixture root for `borrowser-html-parser-fixture-v2`. Discovery
 is recursive and sorted by normalized repository-relative bundle path. Add a
 directory containing `fixture.toml`, exact input, and declared snapshots; no Rust
 registration is required.
@@ -12,7 +12,7 @@ directory containing `fixture.toml` is a leaf; nested bundles are rejected.
 Native fixtures in this directory must be `source = native` and
 `disposition.status = active`. Xfail, skip, and expected-unsupported entries
 belong only to later external/adapted inputs or a separately identified
-quarantine source. Fixture-v1 permits skips only for an exact unsupported
+quarantine source. Fixture-v2 permits skips only for an exact unsupported
 capability; broad external-source and environment skips are rejected.
 
 Use `input.html` only for valid UTF-8 input whose intended checkout form has LF
@@ -21,11 +21,19 @@ byte delivery, and any byte-sensitive case. `input.html` containing a carriage
 return is rejected. Always update the mandatory SHA-256 from the exact stored
 bytes; the loader never trims input.
 
-AE13a executes only whole-input standalone-tokenizer fixtures with a declared
-`tokens.txt` in `html5-token-v1`. Other fixture-v1 surfaces are declarable but
-fail explicitly as unsupported expectations until their owning AE13 slice lands.
+AE13b5 executes supported whole-input standalone-tokenizer and document
+fixtures from typed canonical observations. Ordinary surfaces are unioned on
+the reference delivery; transition expectations may name another declared
+whole delivery. Each planned delivery executes once. Unused declared whole
+deliveries are capability-checked but do not execute.
 
-See `docs/html5/parser-fixture-format-v1.md` for the complete schema and
+Canonical sidecars use the exact AE13b5 formats, including `html5-token-v2`,
+`html5-dom-v3`, and `html5-dompatch-v3`. Header-only diagnostic, transition,
+unsupported-feature, tree, and patch snapshots represent requested empty
+collections. Fixture-v1 remains an isolated compatibility format.
+
+See `docs/html5/parser-fixture-format-v2.md` and
+`docs/html5/ae13b5-parser-snapshot-formats.md` for the schema/codecs, and
 `docs/html5/ae13-parser-conformance-regression-harness.md` for ownership and
 slice boundaries.
 

crates/html/tests/fixtures/html5/conformance/document-recovery-diagnostics/fixture.toml

@@ -0,0 +1,32 @@
+format = "borrowser-html-parser-fixture-v2"
+id = "document-recovery-diagnostics"
+
+[source]
+kind = "native"
+
+[input]
+path = "input.html"
+kind = "utf8-text"
+sha256 = "f6a8bd0ddf91049b25303c3e04f39f422817603e9a9b4ed051a8d0832294bb8a"
+
+[execution]
+reference_delivery = "whole"
+
+[execution.target]
+kind = "document"
+scripting = "disabled"
+
+[[execution.deliveries]]
+name = "whole"
+unit = "unicode-scalars"
+strategy = "whole"
+
+[expectations]
+parse_errors = "parse-errors.txt"
+implementation_diagnostics = "implementation-diagnostics.txt"
+
+[disposition]
+status = "active"
+
+[metadata]
+description = "Duplicate-attribute and non-void self-closing recovery use typed canonical diagnostics."

crates/html/tests/fixtures/html5/conformance/document-recovery-diagnostics/implementation-diagnostics.txt

@@ -0,0 +1,2 @@
+# format: html5-implementation-diagnostics-v1
+IMPLEMENTATION_DIAGNOSTIC occurrence=1 stage=tree-construction code=tree-construction:non-void-html-self-closing-flag-altered-stack-disposition payload=none position=unavailable:parser-did-not-provide-position context=present context-token=start-tag context-mode=in-body context-namespace=html

crates/html/tests/fixtures/html5/conformance/document-recovery-diagnostics/input.html

@@ -0,0 +1 @@
+<!doctype html><div a='first' a='second'/>

crates/html/tests/fixtures/html5/conformance/document-recovery-diagnostics/parse-errors.txt

@@ -0,0 +1,3 @@
+# format: html5-parse-errors-v1
+PARSE_ERROR occurrence=1 stage=tokenizer code=standard:duplicate-attribute recovery=drop-duplicate-attribute position=normalized-utf8:30:1:31:source-unavailable:no-input-provenance-map context=absent context-token=null context-mode=null context-namespace=null
+PARSE_ERROR occurrence=2 stage=tree-construction code=tree-construction:unacknowledged-self-closing-flag recovery=null position=unavailable:parser-did-not-provide-position context=present context-token=start-tag context-mode=in-body context-namespace=html

crates/html/tests/fixtures/html5/conformance/document-structured-observations/document-mode.txt

@@ -0,0 +1,2 @@
+# format: html5-document-mode-v1
+MODE value=no-quirks