write-tests

A guide for writing or reviewing Jest tests, which are automated JavaScript tests, in a specific codebase. It defines where tests belong and requires integration tests to use real PostgreSQL and Redis services rather than database mocks.

In plain words
What is it for?
Use it when adding tests, testing an action or task, or improving coverage in this codebase. It covers unit, integration, and task tests and specifies how to run them.
Why use it?
It keeps new tests consistent with the repository's conventions and separates business-logic tests from tests of database and HTTP wiring. It also requires error and authorization failures to be covered.

Skill for Claude CodeCodex

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods
npx agentmods add skills/hackbyrd/orbital-express/write-tests
Any agent
npx skills add Hackbyrd/orbital-express --skill write-tests
Clone the repo
git clone --depth 1 https://github.com/Hackbyrd/orbital-express

Made for: Claude Code, Codex.

Per session 66 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,541 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5 $0.00066 $0.01541
Opus 5 $0.00033 $0.00771
Sonnet 5 $0.00013 $0.00308
Haiku 4.5 $0.00007 $0.00154

Measured 2d ago against content hash 247ab2683846, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

write-tests scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 2d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

.claude/skills/write-tests/SKILL.md · 60 lines

How it starts

The opening of the file, as written. The whole thing — 60 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Write tests

Tests use Jest + supertest against a real Postgres + Redis (no DB mocks). Read README "Tests Folder", "Writing Testable Code", "Testing: *" sections. Postgres and Redis must be running, and the suite runs --runInBand (parallel suites race on sync({force:true})).

Writing testable code (do this BEFORE testing)

Separate logic from I/O. An action/task does three things: load (DB/API), process (business logic), save (DB/side effects). Extract the process step into a pure function in helper.js (or the global helpers/logic.js) — plain inputs → plain output, no DB, no API, no req. Then:

  • Test that pure function exhaustively in helper.test.js (every edge case — fast, no DB/server/mocks).
  • Test the action/task integration once (the happy path + error/auth cases) — its only job is to verify wiring (loaded the right record, called the service, wrote the result). Don't re-run every logic edge case through the full HTTP+DB stack.
  • If you can't test a piece of logic without a running DB, that's the signal to extract it.

Where tests live (mandatory — never put a test file anywhere else)

  • app/<Feature>/tests/integration/V1<Action>.test.js — one per action (full HTTP via supertest).
  • app/<Feature>/tests/tasks/V1<Task>.test.js — one per task (call the task fn directly, assert side effects).
  • app/<Feature>/tests/helper.test.js — pure unit tests for app/<Feature>/helper.js (no server/DB).
  • test/helpers/<name>.test.js — pure unit tests for files in helpers/<name>.js.
  • test/services/<name>.test.js — pure unit tests for files in services/<name>.js.

Never drop a test directly in test/ — every test file lives in a sub-folder that mirrors where its source lives. A test for services/email.js goes in test/services/email.test.js; a test for helpers/logic.js goes in test/helpers/logic.test.js.

Every feature retains tests/helper.test.js, tests/integration/, and tests/tasks/; empty integration/task directories use README markers. Restore missing counterparts with yarn repair <Feature> --dry-run, review, then yarn repair <Feature>. Repair never overwrites.

Read the full file on GitHub · 60 lines

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 2d ago First seen · 60 lines · 66 tokens per session scan A 247ab2683846

Subscribe to this mod's changes

write-tests is a skill published in the GitHub repository Hackbyrd/orbital-express (14 stars, last pushed 13d ago), licensed MIT. It adds 66 tokens to every session and 1,541 once invoked, about $0.0003 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.

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