Crate dev_coverage 

dev-coverage

Test coverage measurement and regression detection for Rust. Part of the dev-* verification suite.

Wraps cargo-llvm-cov — the modern Rust coverage standard — and emits results as a dev_report::Report. Compares against a stored baseline to flag regressions so AI agents and CI gates can decide whether a PR drops coverage too far.

Quick example

use dev_coverage::{CoverageRun, CoverageThreshold};

let run = CoverageRun::new("my-crate", "0.1.0");
let result = run.execute().unwrap();

let threshold = CoverageThreshold::min_line_pct(80.0);
let check = result.into_check_result(threshold);

What dev-coverage provides

• CoverageRun — builder around cargo llvm-cov.
• CoverageResult — line / function / region percentages plus per-file breakdown.
• CoverageThreshold — fail when coverage drops below an absolute floor.
• Baseline + BaselineStore — persist per-commit coverage so the next run can flag regressions.
• CoverageProducer — dev_report::Producer integration for pipelines that compose multiple producers via dev-tools.

Requirements

cargo-llvm-cov must be installed on the system:

cargo install cargo-llvm-cov

The crate detects its absence and emits CoverageError::ToolNotInstalled without panicking.

Re-exports

pub use baseline::Baseline;

pub use baseline::BaselineStore;

pub use baseline::JsonFileBaselineStore;

Modules

baseline

Persisted coverage baselines.

Structs

CoverageDiff

Signed deltas between a current CoverageResult and a stored Baseline.

CoverageProducer

Producer adapter that runs a CoverageRun, compares the result against the configured CoverageThreshold, and (optionally) flags regressions against a stored Baseline.

CoverageResult

Result of a coverage run.

CoverageRun

Configuration for a coverage run.

FileCoverage

Coverage measurements for a single source file.

Enums

CoverageError

Errors that can arise during a coverage run.

CoverageThreshold

Threshold defining the minimum acceptable coverage.