Elamur Groupantsalgorithm-bitset-subset-sum-tests
The groupant beside algorithms/src/bitset_subset_sum/tests.rs in the Mova repository: what the code computes, what it never does, how to go back from its outputs, its invariants, cost and checks.
Facts
Implementation material. A Mova code model describes this code at one source revision: partial models, finite checks and their stated scope. It is not a reviewed general exposition, and its labels are shown as written, never raised.
Components
| component | label | where |
|---|---|---|
| approximant | partial | approximant |
| ast | partial | syntax.json |
| descriptant | present | descriptant |
| invariant | partial | approximant |
| tests | existing checks referenced | tests |
Obernants
The typed relations around the forward model: the behaviour complement (what the code never does), the reverse reconstruction (every input compatible with an output) and specialised views.
| id | type | label | where |
|---|---|---|---|
behavior_complement | behavior_complement | partial relational specification | behavior_complement |
reverse_reconstruction | reverse_reconstruction | partial relational specification | reverse_reconstruction |
oracle_separation | oracle_separation | partial relational specification | oracle_separation |
boundary_partition | boundary_partition | partial relational specification | boundary_partition |
compiled_fault | compiled_fault | partial relational specification | compiled_fault |
Model text
descriptant
bitset_subset_sum tests.rs
Original std-only implementation and independent fixtures. Bellman, Dynamic Programming (1957); word-parallel implementation is original.
Prospective model saved before changes in $MOVA_DATA/runs/octopus-wave20-dp-2026-10-30/prospective.md. Current epoch 2026-10-30: exact optimization with explicit bounded-resource outcomes. Finite oracle agreement does not establish the caller's monotonicity premises. No timing or whole-Mova speed claim.
approximant
Forward model
Execute exhaustive finite oracle comparisons and focused boundary assertions for bitset_subset_sum. A mismatch panics; successful observations cover only enumerated fixtures.
Cost
Exhaustive fixture growth is exponential in fixed small dimensions; independent full scans intentionally cost more than optimized source. Test allocation can panic; test harness is not a fallible production API.
Limits
No timing guarantee, allocator injection, or general proof. No useful cheaper executable surrogate for assertions; omitted explicitly.
models
behavior_complement
A successful harness run excludes disagreement on the enumerated fixtures, not on untested inputs; an intentionally changed production recurrence must yield an assertion failure, not merely compilation rejection.
reverse_reconstruction
The same all-pass observation admits distinct implementations agreeing on finite fixtures and differing elsewhere; complete source behavior is not recoverable from test output.
oracle_separation
Small exhaustive expected values use subset enumeration, full row scans, full predecessor scans or cubic BST recurrence, independently of optimized candidate pruning.
boundary_partition
Budget-zero fixtures and empty-domain fixtures distinguish successful mathematical emptiness from rejected resource exhaustion; the two statuses are not interchangeable.
compiled_fault
The production control changes a recurrence comparison, initial reachability or objective result while retaining compilation; the named focused test must reject that semantic change.
tests
Checks
cargo test -p mova-algorithms bitset_subset_sum::tests
Independent small oracle and resource boundary fixtures live in ../tests.rs. Repeated debug/release and compiled mutation receipts: $MOVA_DATA/runs/octopus-wave20-dp-2026-10-30.
combiner
Composition
Raw tests.rs syntax and mathematical recurrence are separate evidence. The partial syntax projection binds the exact source bytes but does not certify the recurrence. Oracle tests compare observable outputs; typed relations constrain lawful transformations and compatible preimages. For bitset_subset_sum, resource caps and checked failures remain separate from mathematical objective equivalence. Prospective expectations remain unchanged; finite validation cannot turn monotonicity assumptions into runtime validation.
validation
Validation — 2026-10-30
Ten new native tests cover five exact kernels. Full mova-algorithms library: 557 tests pass in two debug and two release executions; sorted native test outcomes agree byte-for-byte across all four. Strict all-target Clippy and focused rustfmt pass. External receipts: $MOVA_DATA/runs/octopus-wave20-dp-2026-10-30/{debug1,debug2,release1,release2,clippy}.log.
Compiled production controls: zero initial subset bit, forced zero MITM objective, right-tie SMAWK reduction, forced zero layered-DP objective and forced zero BST objective all fail named equality assertions. Byte restoration followed by full positive library rerun passes. A separate SMAWK interpolation tie mutation fails lawful_matrices after adding half-integer squared-distance centers; the restored focused test passes. Receipts: controls.log, mutant-*.log, restored.log, smawk-restored.log in the same external run directory. The original constant-matrix fixture alone did not distinguish interpolation ties; the stronger fixture closes that observed gap.
Every source/test file has two independently generated identical syntax projections and current source SHA. An isolated ten-leaf modelcheck groupants run reports valid=true, diagnostics=[], ten sidecars, zero missing source sidecars; the temporary collection parent has no sidecar and makes no composition claim. Root integration owns global registry and ancestor binding checks.
No timing speedup, machine-independent resource guarantee, allocation-failure injection, monotonicity validation, or end-to-end Mova improvement is inferred. Successful finite tests certify the listed observations only. No teacher, model, corpus or live database operations were used.
This page in Markdown → https://md.groupants.elamur.ai/free/en/mova/algorithms/src/bitset_subset_sum/tests.rs.groupant/