Elamur Groupantsvalue-cli-subprocess
The groupant beside tools/value/src/main.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 |
| cost | symbolic source derived | invariant-and-cost |
| descriptant | present | descriptant |
| invariant | partial | invariant-and-cost |
| tests | bounded evidence and explicit gaps | 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 source derived model | behavior_complement |
reverse_reconstruction | reverse_reconstruction | partial source derived model | reverse_reconstruction |
stderr_tail | stderr_tail | partial source derived model | stderr_tail |
lossy_utf8 | lossy_utf8 | partial source derived model | lossy_utf8 |
environment_override | environment_override | partial source derived model | environment_override |
spawn_partition | spawn_partition | partial source derived model | spawn_partition |
Model text
descriptant
value-cli-subprocess
Command(args,cwd,envs).output; spawn error context; failed exit returns reversed last-five stderr lines; success returns lossy stdout.
Epoch 2026-10-31
Prospective full-source read preceded edits. Model separates source-derived effects from bounded actual-helper evidence. Bibliography host identity old code admitted foreign authorities; a failing fixture motivated the narrow HTTP(S) exact-authority repair. Other production bytes were retained; added test modules are cfg(test). Topic run now uses the same canonical ID guard for JSONL admission; an old-code failing fixture confirms foreign matched entries remain only in abstract listings. Namespace compilation is representation evidence, not independent runtime coverage. Value workflow and bench transport remain unexecuted. No live data, network, model, DB or benchmark invocation was used.
approximant
Forward model
Command(args,cwd,envs).output; spawn error context; failed exit returns reversed last-five stderr lines; success returns lossy stdout.
Domain and assumptions: Ok requires successful status. Successful stderr discarded. Child env overrides do not mutate parent environment.
This source-derived relation abstracts allocation, formatting and external failures; no executable percentage surrogate is asserted. Categorical decisions/effects have no supported error metric yet. Future budget caps are 1%, 2%, 5%, 10% only.
catalog
Typed model catalog
Subject: exact manifest source SHA-256 and optional byte scope. Domain/assumptions: forward and invariant companion. Observation is one completed helper transition or the stated IO prefix; external interference is excluded for finite fixtures. All models are partial source-derived specifications; the complement is an inner set of excluded behaviors, the reverse a compatible-antecedent relation. Evidence: tests.md; unsampled branches are not proven.
behavior_complement
Nonzero exit cannot return Ok even with nonempty stdout.
Operator and approximation: the stated constraint on the source transition, with all unmentioned state held fixed; not a total solver or uniqueness claim. Falsifiable oracle: compare actual helper outputs/effect order on a bounded input satisfying the domain. Current executed subset and unsupported observations are listed in tests.md.
reverse_reconstruction
Equal lossy stdout fibers include invalid-byte variants and arbitrary stderr for successful processes.
Operator and approximation: the stated constraint on the source transition, with all unmentioned state held fixed; not a total solver or uniqueness claim. Falsifiable oracle: compare actual helper outputs/effect order on a bounded input satisfying the domain. Current executed subset and unsupported observations are listed in tests.md.
stderr_tail
Error suffix=reverse(lines(stderr)).take(5).join(' | '); early stderr discarded.
Operator and approximation: the stated constraint on the source transition, with all unmentioned state held fixed; not a total solver or uniqueness claim. Falsifiable oracle: compare actual helper outputs/effect order on a bounded input satisfying the domain. Current executed subset and unsupported observations are listed in tests.md.
lossy_utf8
Invalid UTF-8 replacement makes byte->String noninjective.
Operator and approximation: the stated constraint on the source transition, with all unmentioned state held fixed; not a total solver or uniqueness claim. Falsifiable oracle: compare actual helper outputs/effect order on a bounded input satisfying the domain. Current executed subset and unsupported observations are listed in tests.md.
environment_override
Explicit child environment overlays inherited environment; inherited keys not cleared.
Operator and approximation: the stated constraint on the source transition, with all unmentioned state held fixed; not a total solver or uniqueness claim. Falsifiable oracle: compare actual helper outputs/effect order on a bounded input satisfying the domain. Current executed subset and unsupported observations are listed in tests.md.
spawn_partition
Missing executable or cwd fails before status observation, unlike spawned nonzero exit.
Operator and approximation: the stated constraint on the source transition, with all unmentioned state held fixed; not a total solver or uniqueness claim. Falsifiable oracle: compare actual helper outputs/effect order on a bounded input satisfying the domain. Current executed subset and unsupported observations are listed in tests.md.
tests
Checks and limits
Exact target-qualified native names for this source family:
- wave33_tests::subprocess_status_precedes_stdout_and_reverses_stderr_tail
Run each selected exact name twice debug and twice release, one test thread, offline/locked dependencies. External wave33 sources receipts contain numeric statuses/raw logs and sorted outcome comparisons. Scoped children inherit only relevant evidence: parse/IDs directly exercised; admission/check/merge actual helpers exercised; subprocess actual helper exercised. bench_transport has source-derived evidence only, never an executed benchmark. Library namespace is compile/representation evidence.
Compiled source controls change bibliography license threshold, sources size guard and value status guard; targeted assertions must reject, then exact backup restoration and positive rerun. Finite controls are not comprehensive fault coverage. See evidence.md at source root for receipts summary.
invariant-and-cost
Invariants and costs
Ok requires successful status. Successful stderr discarded. Child env overrides do not mutate parent environment.
O(child runtime+captured output bytes); no helper output limit, fixtures bounded.
Bounds are symbolic, conditional on stated domain and successful allocation. No unmeasured speedup or universal finite-test guarantee.
This page in Markdown → https://md.groupants.elamur.ai/free/en/mova/tools/value/src/main.rs.groupant/subprocess.groupant/