Generate realistic test data including edge cases and boundary conditions. Use when creating realistic fixtures or edge case test data. Trigger with phrases like "generate test data", "create fixtures", or "setup test database".
npxskills add jeremylongshore/claude-code-plugins-plus-skills--skill generating-test-dataLoading…
Generate realistic, type-safe test data including fixtures, factory functions, seed datasets, and edge case values. Supports Faker.js, Factory Bot patterns, Fishery (TypeScript factories), pytest fixtures, and database seed scripts.
faker.seed())faker.person.fullName() for names, faker.internet.email() for emails).faker.seed(12345)).ON CONFLICT or INSERT IF NOT EXISTS).test/factories/ or tests/factories/| Error | Cause | Solution |
|---|---|---|
| Factory produces invalid data | Schema changed but factory not updated | Add a validation step that runs the factory output through the schema validator |
| Duplicate unique values | Faker generates collisions in small datasets | Use sequential IDs or append a counter; increase Faker's unique retry limit |
| Database seed fails on foreign key | Seed insertion order violates referential integrity | Sort seed operations topologically by dependency; disable FK checks during seeding |
| Factory recursion overflow | Circular relationships (User -> Order -> User) | Limit relationship depth; use lazy references; break cycles with ID-only references |
| Non-deterministic test failures | Random seed not set consistently | Call faker.seed() in beforeAll or at factory module level; document seed values |
TypeScript factory with Fishery:
import { Factory } from 'fishery';
import { faker } from '@faker-js/faker';
interface User {
id: string;
name: string;
email: string;
role: 'admin' | 'user';
createdAt: Date;
}
export const userFactory = Factory.define<User>(({ sequence }) => ({
id: `user-${sequence}`,
name: faker.person.fullName(),
email: faker.internet.email(),
role: 'user',
createdAt: faker.date.past(),
}));
// Usage:
const user = userFactory.build();
const admin = userFactory.build({ role: 'admin' });
const users = userFactory.buildList(10);
pytest fixture factory:
import pytest
from faker import Faker
fake = Faker()
Faker.seed(42)
@pytest.fixture
def make_user():
def _make_user(**overrides):
defaults = {
"name": fake.name(),
"email": fake.email(),
"age": fake.random_int(min=18, max=99),
}
return {**defaults, **overrides}
return _make_user
def test_user_validation(make_user):
user = make_user(age=17)
assert validate_age(user) is False
Edge case data collection:
export const edgeCases = {
strings: ['', ' ', '\t\n', 'a'.repeat(10000), '<script>alert(1)</script>', # 10000: 10 seconds in ms
"Robert'); DROP TABLE users;--", '\u0000null\u0000byte'],
numbers: [0, -0, -1, Number.MAX_SAFE_INTEGER, NaN, Infinity, -Infinity],
dates: [new Date(0), new Date('2024-02-29'), new Date('9999-12-31')], # 2024: 9999 = configured value
};
Create or update AgentSkills. Use when designing, structuring, or packaging skills with scripts, references, and assets.
Create or update AgentSkills. Use when designing, structuring, or packaging skills with scripts, references, and assets.
Set up and use 1Password CLI (op). Use when installing the CLI, enabling desktop app integration, signing in (single or multi-account), or reading/injecting/running secrets via op.
CLI to manage emails via IMAP/SMTP. Use `himalaya` to list, read, write, reply, forward, search, and organize emails from the terminal. Supports multiple accounts and message composition with MML (MIME Meta Language).
Create or update AgentSkills. Use when designing, structuring, or packaging skills with scripts, references, and assets.
Create or update AgentSkills. Use when designing, structuring, or packaging skills with scripts, references, and assets.
Set up and use 1Password CLI (op). Use when installing the CLI, enabling desktop app integration, signing in (single or multi-account), or reading/injecting/running secrets via op.
CLI to manage emails via IMAP/SMTP. Use `himalaya` to list, read, write, reply, forward, search, and organize emails from the terminal. Supports multiple accounts and message composition with MML (MIME Meta Language).