Farshid/Ashouri

pytest

24 posts tagged “pytest”.

  1. 2025

  2. Checking if something is callable or async callable in Python

    I wanted a mechanism to check if a given Python object was "callable" - could be called like a function - or "async callable" - could be called using .

    python asyncio introspection callable testing
    1 min read

  3. Snapshot testing with Syrupy

    I'm a big fan of snapshot testing - writing tests where you compare the output of some function to a previously saved version, and can re-generate that version from scratch any time something changes.

    TIL pytest
    2 min read

  4. Asserting a dictionary is a subset of another dictionary

    Take for example an API endpoint that returns something like this: I want to efficiently assert against the second two keys, but I don't want to hard-code the SQLite version into my test in case it…

    python testing dictionaries pytest
    1 min read

  5. Testing a Click app with streaming input

    For sqlite-utils 364 I needed to write a test for a Click app which dealt with input streamed to standard input.

    TIL pytest
    1 min read

  6. Mocking a Textract LimitExceededException with boto

    For s3-ocr issue 21 I needed to write a test that simulates what happens when Amazon Textract returns a "LimitExceededException".

    TIL pytest
    1 min read

  7. How to mock httpx using pytest-mock

    I wrote this test to exercise some httpx code today, using pytest-mock. The key was to use which patches the module that was imported by the module.

    python testing mocking httpx pytest
    1 min read

  8. Using VCR and pytest with pytest-recording

    pytest-recording is a neat pytest plugin that makes it easy to use the VCR library, which helps write tests against HTTP resources by automatically capturing responses and baking them into a YAML file…

    TIL pytest
    1 min read

  9. Session-scoped temporary directories in pytest

    I habitually use the fixture in pytest to get a temporary directory that will be cleaned up after each test, but that doesn't work with - which can be used to ensure an expensive fixture is run only…

    TIL pytest
    1 min read

  10. Async fixtures with pytest-asyncio

    I wanted to use a fixture with that was itsef as function, so that it could execute statements. Since I'm using a file containing I had to use the fixture to get this to work.

    pytest asyncio python testing fixtures
    1 min read
  11. 2024

  12. Treating warnings as errors in pytest

    I was seeing this warning in a Django project when I thought I was correctly using timezone-aware dates everywhere: RuntimeWarning: DateTimeField Shift.shift start received a naive datetime…

    TIL pytest
    1 min read

  13. Mocking Stripe signature checks in a pytest fixture

    I'm writing some code that accepts webhooks from Stripe. I wanted to simulate hits to this endpoint in my Django tests.

    TIL pytest
    1 min read

  14. Running pytest against a specific Python version with uv run

    While working on this issue I figured out a neat pattern for running the tests for my project locally against a specific Python version using uv run: The new-to-me trick here is that works for adding…

    TIL pytest
    1 min read

  15. pytest coverage with context

    This tweet from \@Mariatta tipped me off to the ability to measure "contexts" when running coverage - as a way to tell which tests exercise which specific lines of code.

    TIL pytest
    1 min read

  16. Start a server in a subprocess during a pytest session

    I wanted to start an actual server process, run it for the duration of my pytest session and shut it down at the end. Here's the recipe I came up with.

    TIL pytest
    1 min read

  17. Registering temporary pluggy plugins inside tests

    While implementing more finely-grained permissions for (issue 8) I decided I wanted to register a Datasette pluggy plugin for the duration of a single test.

    TIL pytest
    1 min read

  18. Mocking subprocess with pytest-subprocess

    For apple-notes-to-sqlite I needed to write some tests that simulated executing the command using the Python module. I wanted my tests to run on Linux CI machines, where that command would not exist.

    TIL pytest
    1 min read

  19. Show files opened by pytest tests

    My test suite for Datasette has grown so large that running the whole thing sometimes causes me to run out of file handles.

    TIL pytest
    1 min read
  20. 2023

  21. Using namedtuple for pytest parameterized tests

    I'm writing some quite complex pytest parameterized tests this morning, and I was finding it a little bit hard to read the test cases as the number of parameters grew.

    TIL pytest
    1 min read

  22. Quick and dirty mock testing with mock_calls

    I needed to write a test that checked for a really complex sequence of mock calls for s3-credentials 3.

    TIL pytest
    1 min read

  23. Writing pytest tests against tools written with argparse

    I usually build command-line tools using Click (and my click-app cookiecutter template), which includes a really nice set of tools for writing tests.

    TIL pytest
    1 min read