llm-ide-rules pytest-tests.instructions.md

Pytest Tests

• Look first to app.factories.* instead of app.models.* to generate any required database state
  • For example, to create and persist a Distribution record DistributionFactory.save()
  • If a factory doesn't exist for the model you are working with, create one.
  • You can customize one or more params in a factory using DistributionFactory.save(host="custom_host.com)
• Use faker factory to generate emails, etc.
• Do not mock or patch unless I instruct you to. Test as much of the application stack as possible in each test.
• If you get lazy attribute errors, or need a database session to share across logic, use the db_session fixture to fix the issue.
  • Note that when writing route tests a db_session is not needed for the logic inside of the route.
• When testing Stripe, use the sandbox API. Never mock out Stripe interactions unless explicitly told to.
• Omit obvious docstrs and comments. Add comments for non-obvious but easy-to-miss lines that are key to what the test is checking.

Example Test

Below is an example test, you'll notice the following:

• Docstr is omitted since the purpose of the test is obvious
• Comment about the county is added since it's the main point of the test
• Newline between test setup, functionality under test, and assertions against result
• api_app_url_path_for helper is used instead of hardcoded routes

from app.generated.fastapi_typed_routes import api_app_url_path_for
import json


def test_calculate_quote_unknown_county(client):
    payload = {
        "subscriber": {"age": 35, "gender": "M"},
        # fake county to ensure error is thrown
        "county": "NotACounty",
    }

    response = client.post(
        api_app_url_path_for("composite_quote"),
        json=payload,
    )

    assert_status(response, status.HTTP_422_UNPROCESSABLE_CONTENT)

File Structure

• If there's more than a handful of tests in a folder, you should probably create subfolders.
• File name should be related to the file or primary class / functionality the test is covering. Do not add a component to the test name that exists in the test file path.
  • Example: app/routes/unauthenticated/quote.py should be tests/routes/unauthenticated/quote_test.py
• tests/routes/{unauthenticated,authenticated} and a handful of top-level test files for fastapi API route testing.
• tests/integration/ for browser tests