ResolvedLayoutIR carried a page/system tree and three flat primitive arrays
with nothing joining them, so a canvas wanting to re-tessellate one damaged
system had to infer ownership spatially — ambiguous exactly where it matters,
at cross-system slurs and boundary-straddling strokes. The partition was
never missing, though: casting-off computes it (system_of_slot, stroke_system,
curve_system) and the fold into ResolvedLayoutIR dropped it. This publishes
it instead of inferring it, so the answer is exact.
ResolvedSystem gains PrimitiveIndices — u32 index lists into the layout's flat
glyphs/strokes/curves — and ResolvedLayoutIR gains an unowned bucket of the
same shape. No primitive is split, merged, reordered, or renumbered; the flat
arrays are exactly what they were. The partition is total and disjoint: for
each array, every system's list plus the unowned bucket covers 0..len exactly
once, tested directly rather than assumed from construction.
Unowned is a first-class bucket with a real producer. The stub solver resolves
no per-system geometry — one default-rect system per region — so it publishes
every primitive unowned rather than fabricating an attribution it never
computed. Cross-system primitives need no special case: casting-off already
splits a spanning stroke or curve into per-system segments carrying
SYSTEM_CONTINUATION_SYNTHESIS provenance, and each segment is owned by the
system it was split into, not by the source's.
Ownership is excluded from the canonical encoding, for the reason vertical_band
already is: it draws nothing, so two layouts differing only in it are the same
rendered layout and hash alike. Encoding it would make the fingerprint more
fragile than the rendering it fingerprints — a casting-off refactor that
re-partitions without moving a pixel would become a byte-level break for
something no renderer and no conformance claim can observe. Verified against
main: all eight reference fixtures produce byte-identical canonical layouts,
and all five GUI goldens are untouched.
One derivation, structurally. The quality census consumed its own copy of the
glyph-to-system rule, and so did vertical_raw's system_of_glyph closure; both
now read the published glyph_system. That left CastLayout::system_of_slot with
no consumer outside the casting pass, so it is removed from the published
struct — a future consumer cannot grow a third copy of the rule, because the
raw material is no longer there. The per-glyph answer travels; the derivation
does not.
Six mutations, each killed and coordinator-re-verified independently: dropping
an index from a system's list, coercing unowned onto system 0, an off-by-one
system index, publishing a constant attribution, attributing a continuation to
its source's system, and encoding ownership into the canonical bytes. The
fourth is the one that proves the single-derivation claim rather than asserting
it — it kills three quality tests, two of which survived it before
vertical_raw was migrated.
Gate: 34 suites / 1341 tests / 0 failed, conformance 9/9 with golden-gate and
8/8 without, requirement labels 6/6 at 212/282/282, clippy 0, five goldens
byte-identical.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Closes P13-S12. epiphany-layout-ir defined its own SmuflVersion storing the
minor LITERALLY ({1,4} for SMuFL 1.4), so derived Ord sorted 1.3 and 1.4
BEFORE 1.12 — backwards versus SMuFL's real release order — on a direct field
of GlyphCatalogIdentity, which is layout-conformance identity. That bug was
live. The crate graph fixes the direction: layout-ir depends on core, so
core's fraction-normalized minor_centi type is necessarily the survivor.
layout-ir deletes its own and re-exports core's, keeping
epiphany_layout_ir::SmuflVersion resolving for downstream at zero churn.
No wire change: no schema major, no Codec, no decode vector. LayoutCache is a
regenerable major-0 role. The one line that moves bytes is encode_catalog's
.minor -> .minor_centi (04 00 -> 28 00 at offset 2, verified by encoding a
default identity: 60 bytes, unchanged elsewhere).
The tranche also closes S12's OTHER half, which had gone unnoticed: the
ratified shape reached Rust and the binary companion but core_spec.tex never
defined SmuflVersion at all — the exact "undefined leaf" S12 was filed about.
It is now declared once, with the hundredths rule as normative prose and the
release table as a rationale note, cross-referenced from both Chapter 9 sites
so the glyph catalog's version and the tuning context's are visibly one type.
No new req: label; counts stay 212/282/282.
Two ledger claims corrected, both verified false before dispatch rather than
after: PASS13_CANDIDATES.md's S12 entry and epiphany-core/DECISIONS.md's S12
bullet both promised this move would land "with golden regen". Nothing is
pinned to the catalog identity — every ResolvedLayoutIR::canonical_bytes()
assertion is RELATIVE (stability, determinism, and a sensitivity check that
mutates metrics_hash, never smufl_version), and the committed SVG/PNG goldens
embed no identity, only a fixed comment string. There was nothing to
regenerate, and conformance gate [9] never moved.
The fix is locked by a test that names the bug: layout-ir asserts the real
release order through GlyphCatalogIdentity.smufl_version. Mutation-verified
independently by making from_decimal store one-digit minors literally — it
fails with "minor_centi: 20 did not sort before minor_centi: 3", which is
precisely the deleted type's behaviour.
Gate: fmt clean, clippy 0, 1283 passed / 0 failed (+1, the new test), doc 0,
conformance 8/8, requirement labels 6/6 at 212/282/282. No golden, vector,
baseline, or editor-track file changed.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Stroke and Curve gain `vertical_band: VerticalBandId`, the field GlyphObject has
always carried. Curve's own doc comment used to call it "a *free* primitive (no
vertical band, no spring slot)" -- but the projection computed each primitive's
band, used it for the glyphs, and threw it away for the strokes and curves.
The engraver then reconstructed it geometrically, and got it wrong twice: nearest
glyph by x handed a lower-staff stem to the upper staff (4132a7a), and nearest
glyph to a slur's start endpoint handed a bottom-staff slur to the top staff
(b1bfe04). Both tore primitives off their own notes, both reached a committed
golden, both were caught by review rather than by the gate. A slur is the proof
the inference can never be made safe: its endpoints are deliberately lifted clear
of its own staff, into the zone where the nearest notehead belongs to the
neighbour. No distance metric recovers the owner.
Both fixes were correct and both were the wrong shape -- reconstructing by
inference a fact the projection had in hand and discarded. So: the projection
declares it (a slur's staff is its notes' staff), the engraver's attribution
becomes three map lookups, and ~60 lines of geometric rules, epsilons, and
fallbacks are deleted.
Two bands had to become unconditional, since strokes could otherwise name bands
that no glyph had caused to exist -- validation now rejects that as UnknownBand:
- a staff band per staff of the region, in the region's own staff order (the
order y_origin stacks by), not only for staves that emitted a glyph. A staff
whose clef is unbundled engraves to an anchor *stroke* and no glyph.
- the margin band unconditionally, because a region's own traced anchor is a
stroke that names it whether or not a margin glyph puts a member in it.
Both may carry zero members, as an inter-staff gap band already did: membership
realizes the spring solve over glyphs; existence is what attribution needs.
Strokes and curves are deliberately NOT added to VerticalBand::members -- their
band reference is one-way.
vertical_band is not part of ResolvedLayoutIR::canonical_bytes (primitives are
encoded field-by-field), so this is layout metadata outside the canonical
encoding: no companion-version bump, and ENGRAVER_VERSION stays at 11 because the
output is unchanged. Zero goldens churn -- which is the evidence that the declared
owner agrees with the inferred one across the entire corpus.
Locked by every_stroke_and_curve_names_a_band_that_exists, verified by mutation:
making the margin band conditional again fails it on valid_score_rich. The two
tear-off regressions are kept -- they now assert an outcome the data model
guarantees, which is where a dropped declaration would surface.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
The third pipeline primitive kind, review-hardened (5 verified findings fixed
pre-commit). A `Curve` (four control points, mirroring `Stroke`) threads
through all three IR stages, the canonical-encode fingerprint (a 5th u32 count
prefix; width-lock 4→5), the round-trip provenance chains and count identity,
`to_render`, the stub solver, engrave remap + casting, SVG path emission, and
hit-testing.
Slurs draw as one cubic bézier per slur carrying the slur's exact provenance
(no synthesis). LayoutContent::Slur resolves each endpoint event to a Note
column at to_logical (SlurEndpoint At/Unresolved — E1's honest-placement
discipline); a symmetric arc whose apex sits `height` from the endpoint line;
curvature_override direction+height honored, style.line (dashed) deferred to
Push 3. Honest non-drawing (traced anchor kept) for an unresolved endpoint, a
non-left-to-right span, or a cross-staff slur (no single staff — would float
at yo=0). Authored height/thickness sanitized to defaults when non-positive
(a negative thickness would else fail validation and blank the layout).
Hit-test: HitShape::Curve (Copy) flattens the cubic to a 16-segment capsule
inside contains/intersects (one region per curve); a slur click resolves to
Slur generically (no editor arm; edit ops refuse it). render-svg: stroked
unfilled <path C> after strokes/before glyphs + curve_count + content-hull
bounds. engrave: HorizontalRemap::curves; casting curve_system = Rigid-to-
start-system (no de Casteljau split — deferred; break-spanning slur draws
whole in its start system, kept for the source surjection); ENGRAVER_VERSION
4→5; slur_shape_penalty now 0.0 by construction (Minimal draws the ideal arc).
Existing SVG goldens changed only in the provenance-note comment (curves now
enumerated) — geometry byte-identical; 6 snapshots gained curve_count; new
ten_measure_with_slurs goldens. 929 tests, conformance 8/8.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
857 workspace tests pass; clippy -D warnings, fmt, and rustdoc clean;
both new companions build with zero undefined references.
Quality Metric Catalog v0.1.0 (spec/quality_metric_catalog.tex, new):
- Formal definitions for all nine normative quality metrics, each with
a raw measurement over resolved geometry and a clamped-linear
normalization n = min(1, raw/R_worst) with pinned anchors.
- The vacuous-geometry rule (a metric over absent geometry evaluates
to 0.0; the notated-but-unrendered honesty edge is an open
question), all-1.0 default tie-breaking weights, and the per-tier
threshold table — Minimal's uniform 0.90 deliberately fails the
all-worst placeholder, forcing real measurement.
- Pins QualityMetricKind (referenced but never defined by the core
spec) and the registered SolverProfile catalog (Draft selects the
Minimal threshold column; Standard/Publication select Standard).
- QualityFloorApproached fires at 0.8x the applicable threshold and
is status-neutral by requirement.
Reference Suite v0.1.0 (spec/reference_suite.tex, new):
- Six entries referenced by deterministic builder + seed (RS-1
ten_measure_single_staff, RS-2 valid_score_rich, RS-3..6 corpus
fixtures), each with the declared A4-at-8mm-staff solve geometry
(Canvas.layout_defaults has no graph home yet, P12-I7).
- All entries required at Minimal; the same set is the pre-declared
Standard bar (no implementation claims Standard yet). Fixed-
expectation tests deliberately unused in v0.1.
Real metrics in the engraver (engrave/src/quality.rs, new;
layout-ir/src/quality.rs = the catalog constants transcribed):
- QualityMetricVector::unmeasured() replaced with computed values:
collision sweep with the catalog's same-slot-cluster and stroke
exclusions, per-system spacing CV, vertical gap deviations,
system-break slack, page fill, casting-off width CV, symbol
density; slur/beam vacuously 0.0 (no drawn geometry exists).
- Bit-identical across repeated solves (tested); floor warnings never
change solve status; malformed inputs keep unmeasured(). The two
all-worst test pins now assert real values; the StubSolver's
unmeasured() stays (Stub genuinely computes nothing).
Reference-suite harness (testkit reference_suite module + tests):
- Each RS entry asserts the four-condition Minimal pass (hard
constraints, byte/bit determinism, well-formed Minimal report,
every axis within threshold) under the F1 Pass/Xfail discipline,
with the measured table printed per run.
- HONEST FINDING, day one: RS-1 fails Minimal casting-off (measured
1.0 vs 0.90) — greedy first-fit leaves a two-measure stub last
system (width CV 0.6145). Encoded as an asserted Xfail row (fails
on XPASS) and filed as P12-I11 (engrave balance pass, or catalog
revision). P12-I12: the Standard spacing floor warns on short
scores with wide lead measures.
Multi-system click-to-insert fix (editor-core):
- Casting-off exposed two inversion breaks: position_anchors fed a
non-monotonic cross-system anchor list into a monotonic inverter
(system-2 clicks resolved to system-1 times), and
nearest_manifestation found only system 1's staff-line segment
(system-2 clicks got system-1 pitch geometry).
- Fixed with a containing-system lookup over the resolved pages tree
(containment, else nearest by vertical distance), per-system staff
resolution, and per-system anchor filtering; degenerate-geometry
fallback preserves the flat path, so all 84 pre-existing
editor-core tests pass unmodified.
- Five regression tests through the real Engraver over the wrapped
ten-measure fixture, each shown to fail without the fix; testkit
gains dev-only dependencies on editor-core and engrave.
Trackers: P12-I11/I12 filed; DECISIONS entries in engrave, layout-ir,
and testkit; Phase-3 memory updated.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01NEs4aYiu8MXjdYdMxw8PTd
The chosen Phase-3 attack, run as two parallel waves. 829 workspace
tests pass; clippy -D warnings, fmt, and rustdoc clean; all three
spec documents build with zero undefined references.
Casting-off (epiphany-engrave/src/casting.rs, wired into the
Engraver):
- Greedy first-fit system breaking per region at measure-start
barline columns; a measure that would overflow the content width
starts a new system. Hard SystemBreakAt/PageBreakAt always
honoured; soft breaks honoured unless pathological (skipped with
the spec's warning + IrOverride-recorded decision).
- Vertical stacking from real content extents with the inter-system
gap read from the vertical band model; page overflow starts the
next page. World frame: pages stacked vertically, coordinates
baked into glyphs/strokes, so the SVG renderer, hit-testing, and
the GUI viewport are unchanged.
- Real ResolvedPage/ResolvedSystem trees (1-based page numbers,
content bounding boxes, staves from staff-line segments, measures
from barline columns); every chosen break appends an
EngravingDecision with MUSCLOID EngravedBreak provenance,
UserOverride-attributed via the new ConstrainedLayoutIR
break_origins sidecar; staff lines split per system with
synthesized continuation provenance.
- Break-constraint evaluation flips: satisfied iff the layout breaks
at the slot. The two single-system tests invert deliberately
(a hard break is now honoured; a user break is honoured and
attributed instead of warned). Geometric constraints evaluate in
the pre-casting spaced frame (documented).
- Page geometry is engraver-side PageGeometry (A4 portrait at an
8 mm staff: page 105 x 148.5 staff spaces, margins 7.5, content
90 x 133.5; arithmetic documented) — Canvas.layout_defaults has no
graph home and is a schema-major addition (P12-I7).
ENGRAVER_VERSION = 2. Goldens regenerated: ten_measure_single_staff
engraves as 2 systems (viewBox 84x20.6, was 103x11);
valid_score_rich as 3 systems; stub goldens byte-identical.
K1 schema-fill (Operation Catalog 0.4.0 -> 0.5.0, ratified first;
wire discriminants strictly appended):
- CreateStaff (24 / tag InsertStaff 24): set-union mint of a global
Staff; CreateStaffInstance now preconditions that its referenced
staff is live.
- SetTimeSignature (25): value-carrying meter-change LWW keyed by
(region, resolved position); the carried TimeSignature mints
set-union; StructuralFieldCollision on meter_sequence.
- SetTempoSegment (26): LWW keyed by (scope, resolved start) over
the score or region tempo map; a write that would malform the map
refuses with the appended PreconditionFailureReason 11
(TempoMapMalformed).
- SetStaffLayout (27): LWW advisory over the staff instance's three
inline layout fields.
- Create score/canvas remain deliberately unavailable slots: the
root and canvas are inline singletons with no addressable object
model (P12-K8), not force-designed.
Value-restoring undo (P11-C8 narrowed; catalog §UndoTransaction
rewritten and per-primitive undo notes updated):
- Canonical-order write chains (base-seeded) across all eleven LWW
families. StrictInverse restores each written key to its
chain-predecessor value iff the transaction's write is still the
key's last writer, else refuses the whole undo with a
TransactionConflict naming the superseder; BestEffort restores the
still-last keys. Clean compensations are Applied; only minted-
object tombstone repairs ride AppliedWithRepair (no new repair
vocabulary). Mixed mint+overwrite transactions compose; strand
guards refuse tombstoning mints still referenced by live
non-members.
- Undo-of-undo pinned and tested: restorations are chain writes, so
undoing the undo's transaction restores the undone value, and a
second undo of the same transaction conflicts (absence-restores
repeat idempotently — documented asymmetry, P12-K11).
- Permutation invariance pinned across five delivery orders; the
convergence generators gain the new ops and a tx-then-undo flow.
- Still deferred in normative text: delete resurrection (needs a
system-derived tag outside the ratified closed set), Transpose
inversion (P12-K2), Cascade dependent closure.
Trackers: Binary Format companion 0.1.0 -> 0.2.0 (appended wire/tag
tables, PreconditionFailureReason 11, payload layouts, history row —
a schema-minor evolution under its own rules); nine new Pass-12 rows
(C5, K8-K11, I7-I10); core-spec OperationKind listing gains the four
kinds; revision-history rows in core spec and companion.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01NEs4aYiu8MXjdYdMxw8PTd
Two audit pushes whose code edits interleave line-by-line in the same
files (reduce.rs, bundle.rs, the DECISIONS logs), committed together so
the tree at every commit builds. Gate: 784 workspace tests pass, clippy
-D warnings clean, fmt clean.
Push 1 — the true MUST violations, all fixed:
- bundle: zstd read support on both read paths, output bounded by the
declared uncompressed_length, typed decompression errors, explicit
CompressedManifest rejection (zstd 0.13 workspace dep; write path
stays uncompressed per the Phase-3 deferral).
- ops: system-derived counter collision check — mint registry seeded
from the base graph, canonical-order pre-walk, halt via the new
PendingReason::HaltedBySystemCollision (discriminant 4, additive)
with transaction-atomicity and causal-dependent closure; neither
input set occupies a collided counter. canonical_pitch_bytes made
pub in core for the MUSCSPCH preimage.
- ops: Transpose skips tombstoned targets per the catalog; missing
targets still refuse the whole operation.
- ops: marker re-anchoring recorded as a RepairRecord in the
triggering operation's effect; ResolveConflict meta-conflicts name
both resolvers; base-free pitch-id freshness; reserved effect
vocabulary annotated.
- core: decomposition pre-pass honors authored attachments
(resolve_decomposition, spec-default precedence); inversion
tolerance typed as a TempoIntegration-class Tolerance.
- CONFORMANCE.md: the determinism conformance statement required by
Appendix D — all seven declarations.
Push 3 — wiring the types-only machinery:
- layout-ir/engrave: to_constrained emits real constraints (successive
notehead no-collision chains, per-glyph region containment, soft
user-break constraints); ConstraintStrength{Required, Preferred}
with strength-by-rule; Preferred violations surface as warnings, not
failures; StubSolver reworked honest-but-renderable. SVG goldens
byte-identical; snapshot constraint counts regenerated (0->90/15).
- layout-ir: to_logical projects user system/page breaks as anchored
EngravingOverrides with paired UserOverride-sourced decisions
(OverrideKind::SystemBreak/PageBreak carry TimeAnchor, ratified in
the spec alongside).
- layout-ir/ops/editor-core: edit-barrier bridge — decode mirrors for
the whole barrier tree (reject-never-normalize, NFC revalidation,
MAX_CONDITION_DEPTH = 64), golden-locked blob codec for the
ExtensionDeclaration fields, a barrier gate in apply and
apply_transaction backed by a Score oracle and real containment
contexts, and apply_unsafe recording the crossed extensions in
extensions_requiring_tombstone() for the next bundle write.
- ops: ResolveEquivocation meta-operation per the newly ratified
catalog entry — payload discriminant 3 (appended), set-level
earliest-resolve-governs promotion, ResolveConflict-mirrored
meta-conflicts, permutation-invariance fuzz; the missing golden
locks on the OperationKind/OperationPayload wire tables added.
- ops/editor-core: validation modes — ValidationMode + a non-canonical
advisory layer (validate.rs), an authoring gate before minting, and
reduction pinned as replay mode by construction (canonical bytes
untouched).
- bundle: the operation index (opindex.rs) — provisional golden-locked
payload, binary-search locate, staleness defined as full-ChunkRef
set equality against operation_roots, and the reject-and-rebuild
discipline (a defective index is never bundle corruption).
- ops: re-anchoring rule table completed — the four-key "nearest"
ordering computed from base-free ledger indices; markers re-anchor
to the nearest live event in the same staff instance (replacing the
Push-1 region-start stand-in); cue-source cascade; graphic-gesture
Events/Range/Free rows; comment and analytical-annotation orphaning.
Zero appended discriminants.
Spec enablers ratified with Push 3: catalog §ResolveEquivocation
(0.3.0 -> 0.4.0) and anchored break overrides; 16 new Pass-12 rows
filed (C1-C4, K5-K7, I4-I6, D1, E1-E5). The data-model payload
expansion (SlurKind, beam geometry, voltas, instrument bodies,
metadata) is deliberately staged to the Binary Format companion — the
positional graph codec has no value-level versioning, so filling those
structs is a schema-major break that should land once, with J.
Also carries the pre-existing editor-track increment: the atomic
tuplet overwrite (CascadeDeleteTuplets prunes decomposition
attachments naming the cascaded tuplet).
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01NEs4aYiu8MXjdYdMxw8PTd
Turn the Score -> layout-IR -> SVG pipeline from placeholder glyphs into real
music notation, rendered through the stub solver and the real Engraver alike.
to_constrained (the spacing pass) now dispatches each layout object to the
notation primitive that represents it, on a column-based spring model:
- Pitch -> notehead at its clef-relative staff position; chord pitches share
one column slot. StaffInstance -> clef glyph. Staff -> five staff-line
strokes (the bottom line its anchor, four synthesized). Pitched Event ->
stem stroke; Measure -> barline glyph; rest Event -> rest glyph.
- Phase 3 ornaments as synthesized glyphs: a spelling's full accidental stack
left of its notehead, a key signature's clef-relative sharp/flat zigzag in
the lead, and a measure's numerator/denominator time-signature digit pair.
- A tied decomposition draws one notehead/stem/rest per component (offsets
honored, not collapsed). Active clef and key resolve by time, not vector
order. The lead area reserves clef + key-signature width.
- Coverage/surjection preserved so the round-trip holds: each laid-out object
is covered by exactly one exact-provenance primitive, and derived primitives
(staff lines, components, accidentals, key/time glyphs) are synthesized from
a laid-out source. Engraving-coverage gaps (missing spelling, unbundled
glyph) are surfaced as ConstrainedLayoutIR diagnostics, not silently
defaulted. A measure depends on the time signature it displays.
The Engraver re-spaces glyphs AND the strokes that track them through one
collision-aware coordinate map (per-slot left/right bearings, pairwise
advances), so stems / barlines / staff lines stay attached and a note's
accidental never overlaps the previous note. validate() now rejects empty
spring slots -- the contract that map relies on -- and to_constrained never
emits one (slots are realized by glyph occupancy).
Bundle the genuine Bravura outlines and metrics for time-signature digits 0-9
(regenerated from the SHA-pinned font via tools/extract_bravura_outlines.py),
replacing an inconsistent hand-written placeholder.
Regions tile left-to-right (no page casting-off yet). Goldens regenerated into
recognizable notation. Full gate green: build, fmt, clippy, 574 tests,
conformance scale 1.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
E-D (layout-ir, honest solver tier): add SolverTier::Stub (a non-conformance rung
below Minimal) and have StubSolver report it instead of falsely claiming the
Minimal conformance tier; the passthrough evaluates no constraints and computes
no quality metrics.
E-C (layout-ir, constraint/reference validation): ConstrainedLayoutIR::validate()
now also checks the LayoutConstraint vector — NoCollision/Align/PositionWithin
must name glyphs in the set, SystemBreakAt/PageBreakAt must name existing slots,
PositionWithin regions must be finite/non-negative — rejecting dangling
references instead of silently accepting them.
E-B (layout-ir, content-sensitive ScoreVersion): derive ScoreVersion from the
whole score's canonical bytes (Agent B's whole-score codec) rather than the
layout projection's object identities, so a pure content edit that changes no
identifier still changes the version — required for correct incremental-layout
cache invalidation.
D-A (bundle, extension-root preservation): Bundle::commit now enforces
preservation — after the builder closure runs, every prior extension declaration
it did not re-declare (by extension_id) is carried forward verbatim, so an
extension-unaware writer cannot silently orphan an unknown extension's
preserved_chunk_roots. An extension-aware writer that re-declares its id keeps
control.
Each fix has a regression test; per-crate DECISIONS updated. (Item-6 remainder:
D-B operation-block summaries next; E-A real time-axis deferred per request.)
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Implements Agent E per spec/QUICKSTART.md — the layout intermediate
representation (Chapter 7) and the constraint-solver interface (Chapter 9):
* Four IR stages: LogicalLayoutIR -> ConstrainedLayoutIR ->
ResolvedLayoutIR -> RenderIR (interface only), with the composite-object
taxonomy, spring slots/constraints, vertical-band model, pages/systems,
engraving decisions + overrides, and the incremental dependency/cache model.
* TimeAxisModel tagged enum (Metric/Proportional/Aleatoric/Registered).
* Provenance back-references with manifestation- and synthesis-aware ids
((source, region) and (source, kind, ordinal)), so multiply-manifested and
synthesized objects never collide.
* In-tree Bravura GlyphCatalog (Send+Sync, metrics + render-data interface),
MUSCFNTM-tagged metrics hash with anchors hashed as a name-keyed map.
* Edit-barrier types keyed on OperationKindTag, with precise EditContext /
EditOracle scope/condition evaluation.
* StubSolver: returns SolveStatus::Solved with the input geometry verbatim;
spec-compliant SolveReport, Minimal tier + all-worst (unmeasured) metric
vector (no false conformance claim); rejects ill-formed input.
* f32 staff-space IR coordinates, quantized to the 1/1024 grid only at
canonical ResolvedLayoutIR serialization (Appendix D); non-finite geometry
is rejected, not normalized. Canonical encoding is injective in glyph
identity, provenance, engraving decisions, and catalog identity.
Re-points Agent F's testkit layout harness from its in-tree stub to the real
crate (v0 acceptance criterion 6) and expands its generators to E's public
surface. Expands Agent C's OperationKindTag to the full normative variant set
so edit barriers can prohibit every operation class.
Workspace gates green: fmt, clippy -D warnings, 377 tests, doc tests, rustdoc
-D warnings, and the conformance suite at scale 1. Decisions and Pass 11
candidates recorded in crates/epiphany-layout-ir/DECISIONS.md.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Levi Neuwirth