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
Criterion 6 (the Chapter 7 layout round-trip) and the render goldens previously
exercised only the verbatim StubSolver, so a regression in the real Engraver's
geometry could land unseen. I-3 drives both through the Engraver.
- round_trip_with<S: ConstraintSolver> factors the solver-agnostic provenance
contract out of round_trip (now a one-line stub wrapper): coverage, the
complete Provenance surviving constrained -> resolved -> render, the source
surjection, and no duplicate stable ids hold for *any* conformant solver. The
Stub tier's verbatim-geometry clause is gated behind solver.tier() == Stub;
every other tier re-spaces. The status gate accepts any renderable status
(Solved / SolvedWithWarnings / PartialBudgetExhausted), not exactly Solved, so
the helper matches its "arbitrary conformant solver" contract while still
rejecting the diagnostic-only statuses that carry no authoritative layout.
- criterion_six_round_trips_through_the_engravers_respacing (epiphany-engrave)
runs the full graph -> logical -> constrained -> *engraved* -> render round
trip over the criterion-6 hand-off fixtures -- ten_measure_single_staff (the
measured fixture) and valid_score_rich (cross-cutting tuplet/tie/spanner),
plus valid_score for breadth -- and asserts the whole provenance contract
survives the Engraver's re-spacing. A non-vacuity check confirms the Engraver
genuinely moved geometry, so provenance is preserved *through* a real geometry
change -- the statement the verbatim stub can never make. This adds an
epiphany-testkit dev-dep (no cycle: testkit does not depend on this crate).
- The render-svg engraver acceptance test is upgraded from invariant-only to
byte-locked: new .engrave.snapshot.txt / .engrave.svg goldens for both
fixtures capture the Engraver's re-spaced output (e.g. ten_measure view_box
width 82.26 vs the stub's 88.88, same glyph/stroke/class counts), so an
Engraver geometry regression is caught at the byte level. A companion test
asserts the engrave goldens genuinely differ from the stub goldens, catching
the degeneracy where the Engraver echoes the stub (which would otherwise pass
both golden checks independently).
Also corrects the epiphany-engrave package description, which still claimed it
reports SolverTier::Stub until it earns Minimal (it earned Minimal in I-2).
Full gate green: build, fmt, clippy, 580 tests, conformance scale 1.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Lands the renderer-against-stub slice of Agent I's visible engraving work
(spec/PHASE2_QUICKSTART.md). Two new crates; prerequisites (G Pass 11, H
spelling/decomposition) are in place. Real engraving + Minimal-tier solver
follow next phase.
epiphany-render-svg (the deliverable this phase):
- Renders a ResolvedLayoutIR to well-formed SVG 1.1, drawing each glyph as a
GENUINE Bravura SMuFL outline <path>. Outlines are extracted reproducibly
from the official OFL Bravura.otf by a committed generator
(tools/extract_bravura_outlines.py, OFL.txt); the font is not vendored, only
the generated Rust (src/outlines_generated.rs). Staff-space/y-up coords with
one global y-flip wrapper; viewBox in staff spaces, px scale on the root.
- Non-overreach: every element traces to a ResolvedGlyph (data-prov) or a
declared wrapper; a glyph lacking an outline is surfaced as a diagnostic and
drawn as a fallback rect, never silently dropped.
- Hand-rolled xml::check_well_formed (no XML dep); acceptance tests cross-check
with system xmllint when present.
- examples/render_fixture.rs demo (fixture name -> SVG stdout, --solver=stub|real).
- Golden-locked machine acceptance snapshot + full-SVG golden for
ten_measure_single_staff and valid_score_rich; deterministic output.
epiphany-engrave (honest scaffold):
- Engraver: a deterministic horizontal-spacing pass (first axis of the planned
two-pass spring layout). Reports SolverTier::Stub — NOT Minimal — until it
evaluates the declared hard constraints, guarded by a regression test. The
demo's --solver=real exercises it end to end.
Honesty notes (recorded as Pass-12 candidates P12-I1..I3 in spec/PASS12_BATCH.md
and the crates' DECISIONS.md): the v0 to_logical/to_constrained pipeline is a
structural placeholder (arbitrary glyph per object, y=0), so stub output is not
yet recognizable notation and the QUICKSTART human visual gate is a next-phase
gate; MUSCLOID layout-id derivation stays unwired; bundled BRAVURA_METRICS are
approximations that disagree with the real outlines.
Gates: cargo fmt + clippy -D warnings clean; cargo test --workspace 504 passed,
0 failed, 0 ignored (criterion 6 layout round-trip still green).
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Levi Neuwirth