tooling-catalog

name	tooling-catalog
description	Per-language catalog of test runners, coverage tools, coverage formats, mutation tools, and dry-run probe commands. Use when detecting a repository's test tooling or configuring a lane for any language.

Tooling Catalog

Reference data for configuring TDD Guardian lanes in any language. The detection method lives in commands/shared/detect-tooling.md; this skill holds the facts it needs.

Read the index below, identify the ecosystem, then read only that reference file. Loading the whole catalog wastes context — each file is self-contained.

Reference index

File	Languages
references/js-ts.md	JavaScript, TypeScript, Node.js, Deno, Bun
references/python.md	Python
references/jvm.md	Java, Kotlin, Scala, Clojure, Groovy
references/dotnet.md	C#, F#, VB.NET
references/native.md	C, C++, Rust, Go, Zig, Swift, Objective-C
references/dynamic.md	Ruby, PHP, Perl, Lua
references/functional.md	Elixir, Erlang, Haskell, OCaml
references/data-mobile.md	Dart/Flutter, R, Julia, Shell
references/e2e.md	Cross-language e2e, integration, contract, and load tooling

Manifest fingerprints

Find every match, not just the first — a repo matching more than one is polyglot, and each ecosystem needs its own lane.

Manifest	Ecosystem	Reference
package.json	Node/TS	js-ts.md
deno.json, deno.jsonc	Deno	js-ts.md
bunfig.toml	Bun	js-ts.md
pyproject.toml, setup.py, setup.cfg, requirements.txt, tox.ini	Python	python.md
pom.xml	Java/Kotlin (Maven)	jvm.md
build.gradle, build.gradle.kts	Java/Kotlin (Gradle)	jvm.md
build.sbt	Scala	jvm.md
deps.edn, project.clj	Clojure	jvm.md
*.csproj, *.fsproj, *.sln, Directory.Build.props	.NET	dotnet.md
go.mod	Go	native.md
Cargo.toml	Rust	native.md
CMakeLists.txt, Makefile, meson.build, conanfile.txt	C/C++	native.md
build.zig	Zig	native.md
Package.swift, *.xcodeproj	Swift	native.md
Gemfile, *.gemspec

Coverage formats the gate can read

Every parser is implemented in scripts/tdd-guardian/lib/coverage.js and covered by tests/coverage.test.js.

Format	Produced by	Per-line detail
istanbul-summary	Jest, Vitest, nyc (coverage-summary.json)	No
istanbul-final	Jest, Vitest, nyc (coverage-final.json)	Yes
lcov	node:test, c8, cargo-llvm-cov, lcov, Flutter, bisect_ppx, Deno	Yes
cobertura	tarpaulin, coverlet, gcovr, scoverage, covr, pytest-cov	Yes
jacoco	JaCoCo (Java/Kotlin/Scala/Groovy)	Yes
clover	PHPUnit, Pest	Yes
coverage-py	coverage.py / pytest-cov JSON	Yes
go-cover	go test -coverprofile	Yes
simplecov	SimpleCov .resultset.json (Ruby)	Yes

Prefer a per-line format whenever more than one lane contributes coverage. Only per-line data merges as a true union; summary-only reports fall back to a weighted average that double-counts any line exercised by two lanes. Most tools can emit LCOV or Cobertura with one flag — take it.

Metrics each format actually measures

A dimension a tool does not measure is reported as null, not zero, and produces a WARNING rather than a gate failure. Set that threshold to 0 rather than chasing a number the tool cannot produce.

Format	Lines	Functions	Branches	Statements
istanbul	yes	yes	yes	yes
lcov	yes	yes (when FNF/FNH present)	yes (when BRF/BRH present)	mirrors lines
cobertura	yes	from <method> elements	yes	mirrors lines
jacoco	yes	yes (METHOD)	yes (BRANCH)	mirrors lines
clover	yes	yes	yes (conditionals)	mirrors lines
coverage-py	yes	no	yes (with --branch)	same as lines
go-cover	yes	no	no	yes
simplecov	yes	no	no (without the branch flag)	mirrors lines

Property-testing libraries

policy-core requires an S4-S6 case for every unit that has a law. That requirement is only real if a library exists to express it, so the catalog names one per ecosystem. Where the column says none in wide use, that is the honest answer: fall back to table-driven S2/S3 cases over a hand-written input set, and say so in the matrix rather than pretending a property was checked.

Ecosystem	Library	Notes
JavaScript / TypeScript	fast-check	Integrates with Vitest, Jest, and node:test; shrinks counterexamples
Python	hypothesis	Also has stateful testing for S5 state-machine invariants
Java / Kotlin	jqwik	JUnit 5 engine; @Property alongside ordinary @Test
Scala	ScalaCheck	Bundled with ScalaTest and munit
Clojure	test.check	clojure.spec generators feed it directly
C# / F#	FsCheck, CsCheck	FsCheck drives xUnit/NUnit from both languages
Go	pgregory.net/rapid	Stdlib testing/quick exists but does not shrink; prefer rapid
Rust	proptest, quickcheck	proptest shrinks structurally; both integrate with cargo test
C / C++	RapidCheck	Integrates with GoogleTest and Catch2
Swift	SwiftCheck	SPM package; XCTest-compatible
Ruby	rantly, prop_check	Either works with RSpec and minitest
PHP	eris	PHPUnit integration
Elixir	StreamData	ExUnitProperties ships in the ecosystem; strongest fit for S5
Erlang	PropEr	Also supports stateful/statem models
Haskell	QuickCheck, hedgehog	hedgehog generates and shrinks integrally
OCaml	qcheck

Where properties pay and where they do not

Unit shape	Worth a property?
Serializer/parser pair	Yes — round-trip is the law: parse(print(x)) == x
Money, quantities, ledgers	Yes — conservation across operations
Sorting, ranking, dedup	Yes — ordering, permutation, and idempotence
Retry, cache, upsert	Yes — idempotence under repetition
Rate limiter, state machine	Yes — invariants across transitions (S5, stateful generators)
Search, ranking, compression	Yes, as a metamorphic relation (S6) — there is no oracle to compare against
A formatter with three hard-coded strings	No — S1/S2 says everything there is to say
A thin adapter over one HTTP call	No — the behavior is at the integration lane, not in a generator

When a language is not in the catalog

Do not guess a command. Instead:

1. Read the CI config — the repo tells you what it runs.
2. Read the project's own README/CONTRIBUTING for the documented test command.
3. Ask the user, and state plainly that the ecosystem is not in the catalog.

Then check whether the tool can emit LCOV or Cobertura. Almost every coverage tool can, and either one makes the lane fully supported without any change to the plugin.

Scope

Covers the per-language facts: runners, coverage tools, report formats and paths, mutation tools, property-testing libraries, and probe commands. It is a reference table, not a procedure.

Does NOT cover:

Question	Where
How do I detect which of these a repo uses?	commands/shared/detect-tooling.md
Which tier should this suite gate?	tdd-guardian:lane-policy
How are thresholds enforced against the report?	tdd-guardian:coverage-gate
How is the report parsed and merged?	commands/shared/parse-coverage.md