Julia Tests

Julia Tests

Use this skill for all Julia testing work. Choose the runner first, then load only the matching reference file.

Choose a Runner

• Standard Test.jl and Pkg.test(): open references/testjl.md
• @testitem suites with TestItemRunner.jl: open references/testitemrunner.md
• File-per-test suites with ParallelTestRunner.jl: open references/paralleltestrunner.md

Quick Commands

julia -tauto --project=. -e 'using Pkg; Pkg.test()'
julia -tauto --project=. -e 'using Pkg; Pkg.test(; test_args=["integration"])'
julia -tauto --project=. -e 'using Pkg; Pkg.test(; test_args=["--verbose", "--jobs=4"])'

Default Rule

• Prefer Pkg.test(...) over directly executing test/runtests.jl; Pkg.test

activates the intended test environment and should be the default package validation path.

• For test-only dependencies, use test/Project.toml and add

[workspace] projects = ["test"] to the root Project.toml. Avoid adding new [extras]/[targets] test dependencies except for legacy compatibility.

• For randomized tests, add StableRNGs to the test environment and use

StableRNG(seed) objects passed explicitly to random APIs. Do not rely on Julia's default RNG, Random.seed!, or MersenneTwister for reproducible tests.

• Set JULIA_PKG_SERVER_REGISTRY_PREFERENCE=eager or

ENV["JULIA_PKG_SERVER_REGISTRY_PREFERENCE"] = "eager" before Pkg operations in this workspace. Otherwise just-registered packages can look unavailable and create false resolution failures.

• Never read or edit Manifest.toml directly. If test environments look stale,

run Pkg.update() and Pkg.resolve() in the relevant environment first. If recurrent issues remain, delete the relevant Manifest.toml file and regenerate it with Pkg.instantiate().

• Read Project.toml when needed, but update dependencies and compat only

through Pkg APIs.

Resolve First

• If tests hit unreleased compat or registry lag in a multi-repo checkout,

Pkg.develop(path=...) the local sibling repos into the active env before debugging the tests themselves.

Writing Tests

• Standard @testset organization and common support files:

references/standard-tests.md

• Writing filter-friendly @testitems:

references/testitem.md

• Writing file-per-test suites for ParallelTestRunner.jl:

references/parallel-files.md

Extra References

• Conditional loading and environment-based test selection:

references/conditional.md

• Local code coverage checks and reports with LocalCoverage.jl:

references/localcoverage.md

• Advanced ParallelTestRunner.jl setup:

references/parallel-advanced.md

Notes

• Keep doctest authoring and Documenter-specific setup under julia-docs.
• Keep JET-specific analysis workflow under julia-jet.
• Prefer one top-level testing skill and a few narrow reference files over many

sibling skills.

Source & license

This open-source skill is cataloged on AgentStack and links to its original source — we do not rehost the code.

• Author: Krastanov
• Source: Krastanov/JuliaLLMAgentSkills
• License: Unlicense

Install and usage instructions live in the source repository linked above.