mathlib-http

The groupant beside tools/mathlib/src/http.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	`model.md`
ast	partial	`syntax.json`
composition	partial	Composition
cost	partial	invariant-and-cost
descriptant	present	descriptant
invariant	partial	invariant-and-cost
tests	bounded checks	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
`percent_codec`	percent_codec	partial source derived model	percent_codec
`download_commit`	download_commit	partial source derived model	download_commit
`clock_projection`	clock_projection	partial source derived model	clock_projection
`df_output_projection`	df_output_projection	partial source derived model	df_output_projection

Parts

mathlib-http-codecs

Model text

descriptant

mathlib-http

Polite gates each GET by elapsed time, returns nested transport/status results, reads text lossily or downloads through .part with content-length/stream cap, rolling hashes, sync and rename. Helpers hex/encode/civil/free_bytes project bytes, time and df output.

Epoch 2026-10-31

Prospective model retained before changes. Existing production bytes are preserved; additions are bounded inline tests. Nine source groupants expose ingestion and routing boundaries; typed children bind exact source bytes and reuse their parent syntax projection. Native tests run twice per profile; behavior mutants run as compiled source changes and exact bytes are restored before positive checks.

Important retained observation: network-looking helpers are not all pure (DNS inside github_host and books build); selection deliberately excludes those effects. Mixed-format manifest order is not deterministic, and error paths do not imply rollback.

No network/DNS/download, real catalog/corpus/model/teacher or database execution. Effect paths are source-derived; finite helper tests are not universal verification. No executable percentage surrogate or speed claim; future caps require metric/domain/reference and remain 1/2/5/10%.

approximant

Forward relation

Model observations include returns, retained state and ordered partial effects; on external failures the successful-prefix relation replaces a total-function claim.

Composition

Scoped children isolate the declared contiguous source intervals. Their operations compose only where the source calls them; costs of overlapping parent/child descriptions are not added twice. Remaining effect paths retain explicit gaps.

catalog

behavior_complement

Subject: mathlib-http, source SHA-256 3df63f2ba1d7bcdb4f0bf02fa7c7a1f0feb5817d22f7409456945ccf6a57aa32; finite transition observation.

Known Content-Length>limit cannot create the .part file. Stream overflow cannot return Fetched. Non-2xx cannot be silently retried inside Polite. Network and filesystem failure paths are source-derived, not exercised.

Domain: stated source predicates, bounded inputs and available resources; arithmetic assumptions and external effect gaps as in the invariant. Operator is the stated relation/projection; complement is a source-derived inner exclusion, reverse retains compatible antecedents. Other views are source-derived partial constraints, not inverse laws.