solvecraft/tests/kernel-cases/README.md

Kernel regression rig

Every geometry case the old kernel (truck) got wrong, recorded in an issue, a pull request or a crash report, is a use case here with its own right answer. The kernel, solidcore, is held to all of them. cargo xtask kernel-cases runs them and writes docs/kernel-cases.md.

This folder takes no new cases. New kernel cases go to solidcore's corpus, solidcore/crates/solidcore/tests/kernel_cases/<area>/ in this repository (the vendored kernel, mirrored to tangency-labs/solidcore; see Exporting to solidcore). CASES lists every case here and only shrinks: cargo xtask lists fails on a case it does not list, and on a listed case that is gone.

cargo xtask kernel-cases                                    # every case
cargo xtask kernel-cases --cli target/release/solidcraft-cli --out /tmp/run   # with a CLI already built
cargo run -p solidcraft-cli -- kernel-cases tests/kernel-cases/booleans/<id>   # one case

The run's output folder (--out, default target/kernel-cases) gets results.json, every case's full result, and dumps/<area>-<case>/: the inputs of each kernel call a case failed in, for replay (the CLI's --dumps=DIR, which the rig always passes). --validation MODE runs the cases' features under that mode of the kernel's check (diagnostics.validation): each_feature (the default: the bodies each feature keeps are checked once), each_step (after every sweep, boolean and blend, as before) or off; the KNOWN_FAILING lists are each_feature's.

Rules

• The answer never comes from a kernel. Not from truck's output, nor any commercial kernel's. It comes from analysis or a hand calculation, or else from the invariants below.
• No user designs. A crash report or a repro design becomes a small synthetic recipe that shows the same geometry. Check for private content before committing anything.
• No workaround on SolidCraft's side. A case that fails stays failing until the kernel is fixed. File SMLib defects as issues here with the area:kernel label; the fix goes into solidcore, and the mirror workflow pushes it to tangency-labs/solidcore.

Layout

One directory per area, one per case: tests/kernel-cases/<area>/<id>/.

Area	Owner
booleans (combine, cuts, holes, patterns, split, mirror, draft)	booleans/shell/import/crash rig
shell (shell, offset, thicken)	booleans/shell/import/crash rig
import (STEP and IGES geometry)	booleans/shell/import/crash rig
crashes (crashes and hangs inside kernel operations)	booleans/shell/import/crash rig
fillets, sweeps, threads, sheet-metal, tessellation	history rig
continuity (designed seams of known order, G0 to G4, that prove the continuity measurement itself)	history rig
solids (cones, scale, align, bounding solids)	tool coverage
frames (frame members, inserted profiles)	tool coverage
plastic (boss, lip and groove, rest, snap fit, plastic rules)	tool coverage rig
surfaces (every surface.* tool: offset, ruled, untrim, unstitch, reverse normal, boundary, blend, match, fair, and a normal and an edge case of each of the others)	surfaces rig
construction (construction planes, axes and points: construct.*)	tool coverage rig
inspect (the inspect commands that return numbers)	tool coverage rig
history (the timeline's suppress, reorder, delete, roll back, edit and folders; configuration rows, columns and rules; parameters that drive geometry)	tool coverage rig
assemblies (joints and couplings, motion studies, contact, components and occurrences, interference and clearance between placed parts: placements and answers worked out by hand)	rig coverage

Each area also has its gate files: KNOWN_FAILING and PATHS (see the gate).

<id> is <source number>-<short-name>, such as 1894-prism-cut-touching-walls. A case from a report with no issue or pull request (a failure the maintainers met in the app) is report-<short-name> and lists no sources; its what says where it was reported. A case that covers a command with no source at all is cov-<short-name>.

Each case has:

• recipe.json: an engine command script ({"commands": [...]}, as solidcraft-cli run takes) or an oracle recipe (tests/oracle/*/recipe.json). $CASE in a string is the case directory, for an input file such as $CASE/input.step (written by hand from the STEP or IGES specification, never a user's file), and $OUT a scratch directory outside the repository for files the case writes (an export).
• expected.json: the right answer, graded by solidcraft-cli kernel-cases.

A script may start with "base": "<case directory>" (relative to its own directory): that case's commands, and its own base's, run first. The ladder's cases build on each other this way.

Each area also has skipped.json (or several, skipped-<part>.json, where an area is triaged in parts): every issue and PR looked at that did not become a case, with one line each saying why.

[{"source": "tangency-labs/solidcraft#123", "why": "UI only: the selection highlight, no geometry"}]

sources.json says what kind each source number is (an open or closed issue, a merged PR, one of the frozen truck-geometry PRs, a kernel-paused PR), for the report's coverage by source.

expected.json

{
  "sources": ["tangency-labs/solidcraft#1894", "tangency-labs/solidcraft#1629"],
  "what": "a prism cut whose walls only touch the target's walls",
  "source": "analytic",
  "method": "box 40x30x20 minus the prism 10x30x5 flush with the side: V = 24000 - 1500",
  "body_count": 1,
  "volume_mm3": 22500.0,
  "area_mm2": 5200.0,
  "faces": 8
}

Field	Meaning
sources	The issues, PRs or crash reports the case comes from (owner/repo#N).
what	One line: the geometry that went wrong.
source	analytic (numbers worked out by hand; method gives the formulas) or invariants (no number is known: only the outcome, validity and counts are graded).
method	How the numbers were derived, or which invariants hold and why.
outcome	solid (default: the script succeeds), refused (the right answer is a clean error, never a panic or a hang), or solid_or_refused (either a clean error or a result graded as usual, where the geometry has no single manifold answer, such as two bodies touching along a curve only).
refusal	Required with outcome: refused (optional with solid_or_refused): a part of the refusal's message, the reason it must be refused for. A refusal for another reason (an SMLib status, a different check) fails.
valid	Default true: every body is one closed shell (or shells in all) that passes the record's structure and geometry checks and SMLib's check(All). false only where the result is legitimately not a solid (a sheet). Where SMLib can't take the record yet (a surface kind its conversion lacks), its check gives no verdict and is not graded.
shells	The total number of shells, where it isn't one per body: a body with a sealed void (2), several lumps kept in one body.
body_count, faces, edges, vertices	Exact counts, where the geometry fixes them. Faces and edges count whole analytic surfaces and curves once (a full cylinder side is one face).
volume_mm3, area_mm2, center_of_mass, bbox	As in tests/oracle: totals over every body, relative tolerance 1e-3 for volume and area, 1e-3 of the box diagonal for positions.
faces, edges, vertices, shells, body_count as [min, max]	An inclusive range, where the geometry only bounds a count (a modelled thread's faces).
volume_mm3, area_mm2 as [min, max]	An inclusive range, where analysis only bounds the measure: a cut removes at most its tool's volume, a join adds at most the tool's. method derives both ends.
continuity	{order, edges}: every seam edges names reaches order (g0 … g4), as Continuity Analysis (inspect.continuity) measures it: from the faces' exact surfaces, at its default 33 stations a seam and its default tolerances (1 µm, 1°, 0.01 / mm, 0.001 / mm², 0.0001 / mm³), never loosened per case. A failure names the worst seam (lowest order; of those, the one furthest past the next order's tolerance), its faces, the order it reaches and that next order's worst value. edges: blend (default), every seam of a face a fillet or chamfer made (a round, a chamfer face or a corner patch) with the faces either side of the edge it replaced, and every seam of a corner patch with the rounds it joins: what the blend is built to meet (not where a round runs into an end face, nor where two rounds meet without a patch: that seam is the input's, tangent only where the rounded edges were); corner, those of them on a corner patch (a blend made from several replaced edges); or a list of points [[x,y,z], …], the edges nearest them, as Continuity Analysis picks them. exact: true: every seam reaches order and not the next (a case built to an order proves the measurement reads that order, no more and no less). A constant round meets its faces G1 (curvature jumps by 1 / r), a curvature round G2, a chamfer G0; a corner: g2 patch is built G2 to the rounds and faces round it.
continuity (older form)	{near, within_mm, clear_mm, curvature_jump_per_mm}: over every tangent seam lying wholly within within_mm of near (a corner's patch and its neighbours), the curvature jump across it (the faces' normal curvatures square to the seam, from their exact surfaces, at 65 stations a seam) is at most curvature_jump_per_mm at every station at least clear_mm along the seam from a vertex where two of those seams turn (where a neighbour's own G1 seam ends, which no surface is G2 to both sides of). A rolling ball's corner jumps 1 / r everywhere.
surface_types	The set of kinds the faces' surfaces are, over every body, as the records hold them: plane, cylinder, cone, sphere, torus, ball_patch (a corner's patch on a sphere, its NURBS net), bspline (a B-spline or NURBS surface), revolution (a revolved curve) or blend (a round by its definition, its NURBS net its geometry). Exact: none missing, none extra.
splines	[{degree: [p, q], spans?: [m, n]}, …]: one entry per B-spline face, each matching one face (directions in either order); spans, the distinct knot intervals each way, only where the construction fixes them.
boundary_edges	The edges only one face uses (a sheet's free boundary), over every body, as the records hold them; exact or [min, max].
flat_pattern	A sheet metal case's flat pattern, from the script's last sheet.flat_pattern result: size_mm ([w, h] of the outline), area_mm2 (the outline's area less the cut-outs', relative tolerance as volume) and bend_lines (each [[x, y], [x, y]], a bend's centre line in flat coordinates, matched one for one, either way round, and as many as the result has), positions within the box-diagonal tolerance.
watertight	true: each body's display mesh (chord tolerance tolerance.mesh_mm, default 0.01 mm) has no open and no over-shared edges, with vertices closer than tolerance.weld_mm (default 1e-4 mm) taken as one.
timeout_s	A longer timeout for this case than the run's (at most 1800 s), for cases that are slow by nature. A case that only needs it on a loaded machine shouldn't set it.
tolerance	Optional overrides: rel, abs_mm, mesh_mm, weld_mm.
files	The files the case wrote to $OUT, each {path, json | csv | dxf}, matched as a part of what is there: every key the case gives, an array item by item and as long, a whole number exactly, any other number within rel. json: the file's JSON; csv: its rows, as objects keyed by the header row; dxf: per layer of its ENTITIES section, how many of each entity ({"CUT": {"CIRCLE": 1, "ELLIPSE": 0, "length_mm": 31.416}}; a count may be a range [min, max]) and length_mm, the total length of its lines, arcs, circles, ellipses and polylines.
results	The commands' own answers, each {step, pointer?, json, rel?, abs_mm?}: the answer of the stepth command (from 1, base commands included), or its part at the JSON pointer (RFC 6901), matched as files matches JSON: a whole number exactly (a count), another within rel (the case's relative tolerance unless given) or abs_mm, lists item by item.
construction	{name: spec}, a spec being {point: [x,y,z]}, {axis: {through, dir}} or {plane: {through, normal}}: each named construction point, axis or plane as the timeline evaluated it. A point within the position tolerance (tolerance.abs_mm, else 1e-3 of the box diagonal, of 1 mm where there is no body); an axis whose direction is parallel to dir (either way, sine of the angle at most 1e-6) and whose line passes within it of through; a plane likewise with normal. An axis or plane is graded as the line or plane it is, not by the origin it keeps.
missing	A capability SolidCraft has no command or parameter for yet ("solid.thread has no start count"): the case is reported not supported yet without running, so the gap stays visible.

The kernel rig gate

Every area is a regression suite: each case is one small case of one issue, with its exact answer. .github/workflows/kernel-rig.yml runs them, and the ladder, on pull requests (not drafts). A plan job (scripts/ci/kernel_rig_plan.py) picks the areas from the changed files, one job builds solidcraft-cli (release) and the rig's runner, and a matrix of shards, one per selected area plus the ladder, runs them in parallel; the kernel-rig check passes when every selected shard does (and when none was selected). Pushes to main and develop, merge groups, the release gate (release-gate.yml) and a run by hand run every area. Each area's shard runs:

cargo xtask kernel-cases --area <area> --cli target/release/solidcraft-cli \
  --known-failing tests/kernel-cases/<area>/KNOWN_FAILING

<area>/KNOWN_FAILING lists the cases of that area that fail today, sorted, one a line with its cause (<case> <why it fails today>; # starts a comment; the header names the baseline: the SolidCore commit it was taken from). The gate fails on a regression, a case that fails (or crashes, hangs, or is not supported yet) and is not listed, and on a fixed case, one listed that passes. With --known-failing the run writes no report; docs/kernel-cases.md stays the full run's.

Updating a list. The pull request that changes an outcome changes the list in the same pull request, so the list only shrinks and never goes stale:

• a fix (yours, or a SolidCore update): remove the line of each case the shard reports as FIXED;
• a case here that starts failing for a reason the kernel owns (a SolidCore update): add its line, sorted, with the cause from its result (results.json in the shard's kernel-rig-results-<area> artifact, or a local run);
• a regression: fix it in the same pull request.

To check a list locally before pushing: cargo xtask kernel-cases --area <area> --cli target/release/solidcraft-cli --known-failing tests/kernel-cases/<area>/KNOWN_FAILING.

Which areas a pull request runs

• <area>/PATHS: the source files whose change reruns that area, one git pathspec glob a line (* within a folder, ** across folders; # starts a comment): the engine command modules, doc evaluation and kernel files its commands go through. Only the area's own files: never a file PATHS-ALL covers, nor a whole crate (the self-test fails on either).
• PATHS-ALL: the shared core, whose change reruns every area: the kernel's wrapper (crates/smlib/**), crates/geom/**, the kernel's core (bodies, extrude and revolve, booleans, the kernel bridge, tessellation, what the grader measures), timeline evaluation, the solid feature commands, the grader, the runner and the workflow.
• A change under <area>/ (a case, its KNOWN_FAILING, its PATHS) reruns that area.
• The ladder spans every operation: it runs whenever any area does, and on a change under ladder/.

The workflow's trigger paths are whole folders that hold every PATHS glob (a self-test, scripts/ci/test_kernel_rig_plan.py, checks it), so a pull request that touches none of them starts no job at all. To see what a change would run: git diff --name-only -z origin/develop... | python3 scripts/ci/kernel_rig_plan.py --paths -.

The plan finds the areas from the folders, so the workflow needs no edit when an area's PATHS changes (unless a glob lies outside the trigger paths, which the self-test reports). No new area joins: new kernel cases go to solidcore's corpus.

Every command has a case

cargo xtask kernel-cases --coverage --cli target/release/solidcraft-cli (run in the gate's build job) lists every registry command (solidcraft-cli commands, planned ones aside) that no recipe.json here runs, and fails unless EXEMPT lists it: one line a command, <id> <why it has no case>, each section sorted. Lines before [to cover] have no geometry to grade (the view, rendering, appearance, files, component and parameter bookkeeping, ...). Lines after it make geometry and wait for a case: that section only shrinks. The check also fails on a listed command that a case now uses (remove its line in the same pull request) or that the registry no longer has. A new command gets an EXEMPT line before [to cover] whose reason names where it is tested: its kernel case in solidcore's corpus, or its test in its area's test file. The build job runs for this check on any change to crates/engine/src/cmd/, a recipe or EXEMPT, even when no area does.

The complexity ladder

ladder/ orders kernel operations by complexity instead of by where they went wrong: tiers from primitives through degenerate booleans, analytic and spline profiles, holes and taps, threads, fillets, chamfers, shells, patterns, whole parts, and sheet metal. Later tiers build on earlier tiers' shapes (a running part grows one tier at a time through base), so the last case carries everything.

• ladder/<NN-tier>/<NNN-name>/: cases in the format above, each a test with its own answer.
• ladder/ladder.json: the tiers in order and, per tier, its cases in order (paths under tests/kernel-cases/, so a tier may also list a rig case from another area).
• ladder/golden.json: per case the status, the commands' time and what was made (counts, volume, area). Runs compare with it and flag slowdowns (over twice the time and 0.25 s more) and changed counts or statuses. It is re-recorded only with a reason.
• tools/kernel-ladder/cases.py writes the recipes and answers (standard-library Python; each method gives the derivation).

cargo xtask kernel-cases --ladder --cli target/release/solidcraft-cli
cargo xtask kernel-cases --ladder --cli target/release/solidcraft-cli --gate
cargo xtask kernel-cases --ladder --cli target/release/solidcraft-cli --record "why"

The ladder needs no known-failing list: the golden is the reference. Its shard in the kernel rig gate runs with --gate, which fails on any case whose status or counts differ from the golden, better or worse, and on a case with no golden; times are not compared there (they are the machine's). A pull request that changes a ladder result re-records the golden with --record "why the golden changes" and commits golden.json and ladder.json with it.

Ladder runs measure one case at a time (unless --jobs) and keep their output in target/kernel-ladder (--out); --record rewrites the golden and sorts each tier by time, fastest first; commit both files. The report, docs/kernel-ladder.md, gives per tier the counts per status and the frontier: the first case in ladder order that fails.

Results

Per case: pass; fail with the numbers; not supported yet (the kernel says so, or the case names a missing capability); crash (a panic caught by the guards, or the process died); hang (no result before the timeout).

Exporting to solidcore

solidcore holds the kernel cases as a corpus of kernel operations, solidcore/crates/solidcore/tests/kernel_cases/<area>/<case>.json, described in that folder's README. cargo xtask kernel-cases [--ladder] [--area AREA] --export DIR writes each case here as such an entry: the kernel operations that made its result, their operand records (<case>.bodies.json.gz), the fix set and the expected values, with DIR/manifest.json listing every case that is not expressible as kernel input and why.

A new kernel case: draft it here as <area>/<id>/recipe.json and expected.json (the format above, answers in closed form or exact), export it with --area <area> --export DIR, add DIR/<area>/<id>.json and its .bodies.json.gz under solidcore, and delete the draft (it is not in CASES, so it cannot be committed here). An entry can also be written by hand as solidcore's README describes. The mirror workflow pushes the change to tangency-labs/solidcore. A case about a command, the UI or a product rule stays in SolidCraft as a test in its area's existing test file.