pytest-schema

0.1.2 verified Mon Apr 27 auth: no python

A pytest plugin that allows you to validate return values against a schema-like object, built on top of the `schema` library. Current version 0.1.2, released June 2024. Low release cadence.

pip install pytest-schema

Common errors

error ModuleNotFoundError: No module named 'pytest_schema' ↓

cause pytest-schema is not installed or installed in a different environment.

fix

Run pip install pytest-schema in your virtual environment.

error TypeError: 'Schema' object is not callable ↓

cause Using the `schema` object from `schema` library directly instead of pytest_schema's wrapper.

fix

Import schema from pytest_schema instead: from pytest_schema import schema.

error AssertionError: assert <pytest_schema...> == ... ↓

cause The schema comparison failed because the actual data does not match the schema.

fix

Check the types and structure of your actual data against the schema definition.

Warnings

gotcha The `schema` callable returns a validator that must be compared with `==` (or `!=`) to actually validate. Simply calling `schema(...)` without comparison does nothing. ↓

fix Always use `assert actual == schema(expected)` or `assert actual != schema(expected)`.

gotcha `like_schema` (or `like`) allows extra keys in the actual dict, while `exact_schema` (or `exact`) does not. Using the wrong one can cause false passes or failures. ↓

fix Use `like_schema` when extra keys are acceptable; use `exact_schema` when the dict must match exactly.

deprecated The methods `like` and `exact` are deprecated in favor of `like_schema` and `exact_schema`. The old names may be removed in future versions. ↓

fix Use `like_schema` and `exact_schema` instead.

Imports

schema
```
from pytest_schema import schema
```
Direct import from pytest_schema
like_schema
```
from pytest_schema import like_schema
```
Alias for like method
exact_schema
```
from pytest_schema import exact_schema
```
Alias for exact method

Quickstart

Basic usage of schema, like_schema, and exact_schema in pytest tests.

from pytest_schema import schema

def test_validate_schema():
    expected = {"name": str, "age": int}
    actual = {"name": "Alice", "age": 30}
    assert actual == schema(expected)

def test_like_schema():
    from pytest_schema import like_schema
    expected = {"id": int, "value": str}
    actual = {"id": 1, "value": "foo", "extra": True}
    assert actual == like_schema(expected)

def test_exact_schema():
    from pytest_schema import exact_schema
    expected = {"key": str}
    actual = {"key": "val"}
    assert actual == exact_schema(expected)