Command and flags

argus [globs...]

Positional arguments are globs of test files to discover and run. With none, the defaults are **/*.test.ts and **/*.test.tsx.

Flags

Flag	Short	Default	Purpose
--timeout <ms>	-t	10000	Per-file Hermes timeout
--concurrency <n>	-c	CPU count, capped at 8	Max files in flight
--hermes <path>		—	Hermes binary to use, overrides ARGUS_HERMES
--engine <name>		project’s pin, preferring V1	legacy or v1
--provision		off	Authorise building Hermes from source
--help	-h		Print usage and exit 0

Environment

Variable	Effect
ARGUS_HERMES	Hermes binary path. Overridden by --hermes.
NO_COLOR / FORCE_COLOR	Honoured — colour comes from Node’s util.styleText.

--timeout

argus --timeout 30000 "src/**/*.test.ts"

Applies to the whole Hermes process for one file, not to individual tests. Exceeding it kills the process and reports the file as timeout, exit code 2.

There is no per-test timeout. The unit of isolation is the file, so the unit of timeout is too.

--concurrency

argus -c 1 "src/**/*.test.ts"    # sequential — useful when debugging
argus -c 16 "src/**/*.test.ts"

Defaults to availableParallelism() clamped to 8. Each unit is a full process, so pushing it far past your core count buys nothing.

Only a strict positive integer is accepted. 0, negatives, 1.5, 1e2 and 2abc are all rejected with a usage error and exit code 2 — a silently coerced concurrency is a performance mystery waiting to happen.

--engine

argus --engine v1 "src/**/*.test.ts"
argus --engine legacy "src/**/*.test.ts"

Only legacy and v1 are accepted. A typo is rejected, never ignored — silently falling back to the default would run the tests on an engine you did not ask for, which is the exact failure this flag exists to prevent.

Asking for an engine your project does not pin is a usage error:

--engine legacy is not available: react-native 0.87.0 pins only: v1.

--hermes

argus --hermes /opt/hermes/bin/hermes "src/**/*.test.ts"

Outranks everything, and is not probed before selection: naming a path entitles you to an error about that path rather than a silent fallback onto another binary.

If it turns out to be a different engine than your project targets, you get the mismatch warning — a warning, not a refusal.

--provision

argus --provision "src/**/*.test.ts"

Authorises a source build when nothing else in the chain can supply a binary. Needs git, cmake and ninja. Never happens without this flag — a multi-minute build is not something to trigger by accident.

Globs

Quote them. Unquoted globs are expanded by your shell before Argus sees them, which usually works and occasionally does something surprising with **.

argus "src/**/*.test.ts"                       # ✓
argus "src/**/*.test.ts" "lib/**/*.test.tsx"   # ✓ several
argus src/cart.test.ts                         # ✓ a literal path

node_modules is excluded from discovery. Report order follows discovery order even though execution is parallel, so output is stable run to run.

A run that matches zero files exits 2. There is no passWithNoTests yet — it is on the roadmap.

No config file yet

Test globs, ignore patterns, timeout, concurrency, esbuild target, module aliases and the JSX runtime are all either flags or built-in defaults. There is no argus.config.ts.

The design is settled — first match wins across --config <path>, argus.config.ts, .mts, .js, .mjs, .config/argus.config.ts, then a package.json field, then built-in defaults; precedence lowest to highest is defaults → package.json → config file → environment → CLI flags. It is not implemented.

Exit codes

Code	Meaning
0	Every test passed
1	At least one test failed
2	Something else went wrong — infra failure, timeout, protocol failure, usage error, or zero files matched

Details: Reporting and exit codes.