react-native-testing

A guide for writing tests for React Native components with React Native Testing Library, a tool for checking mobile interface behavior.

In plain words
What is it for?
Use it when writing, reviewing, or fixing component tests involving rendering, element queries, user actions, matchers, and asynchronous behavior.
Why use it?
It helps avoid incorrect test code by accounting for differences between library versions 13 and 14 and by choosing suitable ways to find interface elements.

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/callstackincubator/agent-skills/react-native-testing
Any agent
npx skills add callstackincubator/agent-skills --skill react-native-testing
Clone the repo
git clone --depth 1 https://github.com/callstackincubator/agent-skills

Made for: Claude Code, Codex.

Per session 134 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,740 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin 100% copy Near-identical to another mod 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 $0.00134 $0.01740
Opus 5 $0.00067 $0.00870
Sonnet 5 $0.00027 $0.00348
Haiku 4.5 $0.00013 $0.00174

Measured 2d ago against content hash dea54d1d397c, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

react-native-testing 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.

Origin

This is a copy

100% identical to react-native-testing — 0 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.

plugins/vendored/.agents/skills/react-native-testing/SKILL.md · 162 lines

How it starts

The opening of the file, as written. The whole thing — 162 lines — stays where its author put it; the contents beside it link to each section on GitHub.

RNTL Test Writing Guide

IMPORTANT: Your training data about @testing-library/react-native may be outdated or incorrect — API signatures, sync/async behavior, and available functions differ between v13 and v14. Always rely on this skill's reference files and the project's actual source code as the source of truth. Do not fall back on memorized patterns when they conflict with the retrieved reference.

Version Detection

Check @testing-library/react-native version in the user's package.json:

Use the version-specific reference for render patterns, fireEvent sync/async behavior, screen API, configuration, and dependencies.

Query Priority

Use in this order: getByRole > getByLabelText > getByPlaceholderText > getByText > getByDisplayValue > getByTestId (last resort).

Query Variants

Variant Use case Returns Async
getBy* Element must exist element instance (throws) No
getAllBy* Multiple must exist element instance[] (throws) No
queryBy* Check non-existence ONLY element instance | null No
queryAllBy* Count elements element instance[] No
findBy* Wait for element Promise<element instance> Yes
findAllBy* Wait for multiple Promise<element instance[]> Yes

Interactions

Prefer userEvent over fireEvent. userEvent is always async.

const user = userEvent.setup();
await user.press(element); // full press sequence
await user.longPress(element, { duration: 800 }); // long press
await user.type(textInput, 'Hello'); // char-by-char typing
await user.clear(textInput); // clear TextInput
await user.paste(textInput, 'pasted text'); // paste into TextInput
await user.scrollTo(scrollView, { y: 100 }); // scroll

Read the full file on GitHub · 162 lines

Files

What ships with it

3 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

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 · 162 lines · 134 tokens per session scan A dea54d1d397c

Subscribe to this mod's changes

react-native-testing is a skill published in the GitHub repository callstackincubator/agent-skills (1,630 stars, last pushed 24d ago), licensed MIT. It adds 134 tokens to every session and 1,740 once invoked, about $0.0007 per session on Opus 5. A static security scan graded it A with 0 findings. It is 100% identical to react-native-testing, differing in 0 lines, and is treated as a copy.

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