feat(coverage-gate): add target-specific policies

Cargo.toml

@@ -41,6 +41,8 @@ cargo-gamma-process = { path = "crates/cargo-gamma-process", default-features =
 cargo-gamma-rt = { path = "crates/cargo-gamma-rt", default-features = false, version = "0.1.0" }
 cargo-gamma-unsafe = { path = "crates/cargo-gamma-unsafe", default-features = false, version = "0.1.0" }
 cargo-heather = { path = "crates/cargo-heather", default-features = false, version = "0.2.1" }
+# external dependencies
+cargo-platform = { version = "0.3.3", default-features = false }
 cargo_metadata = { version = "0.23.1", default-features = false }
 cel = { version = "0.14.4", default-features = false }
 chrono = { version = "0.4.45", default-features = false }

crates/cargo-coverage-gate/CHANGELOG.md

@@ -1 +1,24 @@
 # Changelog
+## [0.4.0] - 2026-08-28
+
+- ✨ Features
+
+  - add target-specific policies
+  - add cargo-aprz and cargo-ensure-no-default-features ([#76](https://github.com/microsoft/ox-tools/pull/76))
+  - run a command per workspace member with cargo-style selection ([#61](https://github.com/microsoft/ox-tools/pull/61))
+  - add expect-no-coverable-lines assertion ([#51](https://github.com/microsoft/ox-tools/pull/51))
+
+- 🐛 Bug Fixes
+
+  - preserve cross-package coverage
+  - resolve effective target policies lazily
+
+- 📚 Documentation
+
+  - document configuration capabilities
+
+- ♻️ Code Refactoring
+
+  - tighten target policy contracts
+  - reuse thresholds for target opt-outs
+

crates/cargo-coverage-gate/Cargo.toml

@@ -4,7 +4,7 @@
 [package]
 name = "cargo-coverage-gate"
 description = "A cargo subcommand that gates pull requests on per-package line coverage measured by cargo-llvm-cov"
-version = "0.3.0"
+version = "0.4.0"
 readme = "README.md"
 keywords = ["oxidizer", "cargo", "subcommand", "coverage", "ci"]
 categories = ["command-line-utilities", "development-tools::cargo-plugins"]
@@ -31,6 +31,7 @@ name = "cargo-coverage-gate"
 path = "src/bin/cargo-coverage-gate/main.rs"
 
 [dependencies]
+cargo-platform = { workspace = true }
 cargo_metadata = { workspace = true }
 clap = { workspace = true, features = ["derive", "std", "help", "usage", "error-context"] }
 lcov = { workspace = true }

crates/cargo-coverage-gate/README.md

@@ -18,8 +18,9 @@
 A pull-request-time gate that compares per-package line coverage produced
 by [`cargo-llvm-cov`][__link0] against per-package thresholds carried in
 `Cargo.toml`. The accompanying `cargo-coverage-gate` binary reads the
-coverage lcov tracefile, resolves each package’s threshold from a small
-three-layer lookup, and emits a verdict table to stdout (and,
+coverage lcov tracefile, resolves each package’s base policy from a small
+three-layer lookup, applies any matching package target policy, and emits a
+verdict table to stdout (and,
 optionally, to a Markdown summary file for CI step summaries). A failing
 verdict includes actionable details without relying on a later
 coverage-service upload. A coverable line is a distinct LCOV `DA:` record.
@@ -28,9 +29,27 @@ Numeric failures show exact covered/coverable counts and uncovered ranges;
 and `NO DATA` explains that no records were attributed. Location lists are
 bounded, with an exact count of omitted locations.
 
-### Threshold resolution
+### Configuration
 
-For each workspace member, the effective threshold is the first match
+#### Numeric thresholds
+
+A workspace can define the default line-coverage threshold:
+
+```toml
+# Illustrative workspace policy.
+[workspace.metadata.coverage-gate]
+min-lines-percent = 80
+```
+
+Individual packages can override it:
+
+```toml
+# Illustrative package policy, intentionally stricter than the workspace.
+[package.metadata.coverage-gate]
+min-lines-percent = 95
+```
+
+For each workspace member, the base threshold is the first match
 among:
 
 1. `[package.metadata.coverage-gate] min-lines-percent = N` in the package’s
@@ -40,13 +59,67 @@ among:
 1. The built-in default of `100.0` — full coverage required.
 
 Setting `min-lines-percent = 0.0` explicitly opts a package out of
-gating (it always passes, regardless of attributed data). A package
-that legitimately contains no coverable lines (pure re-exports, type
-definitions, a thin binary shim) instead declares
-`expect-no-coverable-lines = true`: the gate passes only while that
-holds and fails — as a regression — if coverable lines later appear.
-The two keys are mutually exclusive, and `expect-no-coverable-lines`
-is package-scoped only.
+gating: it always passes, regardless of attributed data. Thresholds must
+be in the inclusive range `0.0..=100.0`.
+
+#### Packages with no coverable lines
+
+A package that legitimately contains no coverable lines (pure re-exports,
+type definitions, or a thin binary shim) can make that invariant explicit:
+
+```toml
+[package.metadata.coverage-gate]
+expect-no-coverable-lines = true
+```
+
+The gate passes only while the package has no attributed coverable lines
+and fails as a regression if coverable code later appears. This differs
+from `min-lines-percent = 0`, which keeps passing if the package grows
+coverable code. The two keys are mutually exclusive, and
+`expect-no-coverable-lines` is package-scoped only.
+
+#### Target-specific policies
+
+A package can replace its base policy for a Cargo-style target selector:
+
+```toml
+[package.metadata.coverage-gate]
+min-lines-percent = 100
+
+[package.metadata.coverage-gate.target.'cfg(not(windows))']
+expect-no-coverable-lines = true
+
+[package.metadata.coverage-gate.target.x86_64-unknown-linux-gnu]
+min-lines-percent = 100
+```
+
+A target-specific no-coverable-lines assertion uses the same nesting:
+
+```toml
+[package.metadata.coverage-gate.target.thumbv7em-none-eabihf]
+expect-no-coverable-lines = true
+```
+
+Target tables are package-scoped; they are invalid in workspace metadata.
+Their keys accept exact Rust target triples or quoted `cfg(...)` expressions
+using the target-derived subset of Cargo’s target grammar. Target
+configuration options such as `windows`, `unix`, `target_os`, and
+`target_arch` are supported. Build-context options such as `feature`, `test`,
+`debug_assertions`, and `proc_macro` are rejected because a standalone target
+query cannot evaluate them. A selected target table sets either
+`min-lines-percent` or `expect-no-coverable-lines = true`, completely
+replacing the package’s base policy to produce its effective policy. Exact
+triples take precedence over matching `cfg(...)` expressions. Multiple
+matching cfg policies are a configuration error rather than depending on
+declaration order.
+
+A zero target-specific threshold disables gating on the matching target,
+but does not disable test execution or instrumentation. Those test binaries
+remain instrumented because they may contribute coverage to other packages.
+If cargo-llvm-cov reports that an instrumented run produced no coverage
+data, automation can supply an empty lcov tracefile: zero-threshold and
+`expect-no-coverable-lines` packages pass, while positively gated packages
+report `NO DATA`.
 
 ### Why lcov, not the JSON?
 
@@ -66,6 +139,7 @@ Codecov / ADO numbers confusing.
 
 ```text
 cargo coverage-gate  [--lcov <path>]... [-p|--package <spec>]...
+                     [--target <triple>]
                      [--summary-file <path>] [--quiet]
 ```
 
@@ -97,25 +171,29 @@ let code = report.verdict().as_exit_code();
 
 ### Public API
 
-The library exposes [`evaluate`][__link1], which returns an
-[`EvaluatedReport`][__link2]. The report can be rendered as plain text via
-[`EvaluatedReport::render_text`][__link3] or as GitHub-flavored Markdown
-via [`EvaluatedReport::render_markdown`][__link4], and reduced to a single
-[`Verdict`][__link5] via [`EvaluatedReport::verdict`][__link6]. The accompanying
-binary loads the lcov tracefile from disk and orchestrates rendering
-plus the appropriate exit code.
+[`evaluate`][__link1] gates one lcov tracefile for the rustc host target, while
+[`evaluate_many`][__link2] merges multiple tracefiles at line level.
+[`evaluate_many_for_target`][__link3] evaluates a selected Rust target, which may be
+supplied explicitly or omitted to select the rustc host target.
+Evaluation returns an [`EvaluatedReport`][__link4], which renders as plain
+text via [`EvaluatedReport::render_text`][__link5] or GitHub-flavored Markdown via
+[`EvaluatedReport::render_markdown`][__link6] and reduces to a [`Verdict`][__link7] via
+[`EvaluatedReport::verdict`][__link8]. The accompanying binary loads tracefiles from
+disk and orchestrates rendering plus the appropriate exit code.
 
 
 <hr/>
 <sub>
 This crate was developed as part of <a href="../..">The Oxidizer Project</a>. Browse this crate's <a href="https://github.com/microsoft/ox-tools/tree/main/crates/cargo-coverage-gate">source code</a>.
 </sub>
 
- [__cargo_doc2readme_dependencies_info]: ggGmYW0CYXZlMC43LjNhdIQbFhzZ8rzWNNYbuRaDSGWynFgbH4PMdoT7GNcbVwNPtPjAhvFhYvRhcoQbSLvuLqYvzncbvkJE0ZCfihkbvLj44R1A234bYHxJKfzepgZhZIGDc2NhcmdvLWNvdmVyYWdlLWdhdGVlMC4zLjBzY2FyZ29fY292ZXJhZ2VfZ2F0ZQ
+ [__cargo_doc2readme_dependencies_info]: ggGmYW0CYXZlMC43LjNhdIQbFhzZ8rzWNNYbuRaDSGWynFgbH4PMdoT7GNcbVwNPtPjAhvFhYvRhcoQb3wjNoVxGaCAbpkmpjr98NCcbw-HRsqJQXfkb8-afvWiSredhZIGDc2NhcmdvLWNvdmVyYWdlLWdhdGVlMC40LjBzY2FyZ29fY292ZXJhZ2VfZ2F0ZQ
  [__link0]: https://github.com/taiki-e/cargo-llvm-cov
- [__link1]: https://docs.rs/cargo-coverage-gate/0.3.0/cargo_coverage_gate/fn.evaluate.html
- [__link2]: https://docs.rs/cargo-coverage-gate/0.3.0/cargo_coverage_gate/struct.EvaluatedReport.html
- [__link3]: https://docs.rs/cargo-coverage-gate/0.3.0/cargo_coverage_gate/?search=EvaluatedReport::render_text
- [__link4]: https://docs.rs/cargo-coverage-gate/0.3.0/cargo_coverage_gate/?search=EvaluatedReport::render_markdown
- [__link5]: https://docs.rs/cargo-coverage-gate/0.3.0/cargo_coverage_gate/enum.Verdict.html
- [__link6]: https://docs.rs/cargo-coverage-gate/0.3.0/cargo_coverage_gate/?search=EvaluatedReport::verdict
+ [__link1]: https://docs.rs/cargo-coverage-gate/0.4.0/cargo_coverage_gate/fn.evaluate.html
+ [__link2]: https://docs.rs/cargo-coverage-gate/0.4.0/cargo_coverage_gate/fn.evaluate_many.html
+ [__link3]: https://docs.rs/cargo-coverage-gate/0.4.0/cargo_coverage_gate/fn.evaluate_many_for_target.html
+ [__link4]: https://docs.rs/cargo-coverage-gate/0.4.0/cargo_coverage_gate/struct.EvaluatedReport.html
+ [__link5]: https://docs.rs/cargo-coverage-gate/0.4.0/cargo_coverage_gate/?search=EvaluatedReport::render_text
+ [__link6]: https://docs.rs/cargo-coverage-gate/0.4.0/cargo_coverage_gate/?search=EvaluatedReport::render_markdown
+ [__link7]: https://docs.rs/cargo-coverage-gate/0.4.0/cargo_coverage_gate/enum.Verdict.html
+ [__link8]: https://docs.rs/cargo-coverage-gate/0.4.0/cargo_coverage_gate/?search=EvaluatedReport::verdict