Topics covered in this episode:

Python 3.14.0 alpha 1 is now available
uv supports dependency groups
dive: A tool for exploring each layer in a docker image
pytest-metadata
Extras
Joke

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Michael #1: Python 3.14.0 alpha 1 is now available

First of seven planned alpha releases.
Many new features for Python 3.14 are still being planned and written. Among the new major new features and changes so far:
- PEP 649: deferred evaluation of annotations
- Improved error messages

Brian #2: uv supports dependency groups

we covered dependency groups in episode 406
as of 0.4.27, uv supports dependency groups
docs show how to add dependencies with uv add --group
- also “The --dev, --only-dev, and --no-dev flags are equivalent to --group dev, --only-group dev, and --no-group dev respectively.”
To install a group, uv pip install --group doesn’t work yet.
- It’s waiting for PyPA to decide on an interface for pip, and uv pip will use that interface.

But sync works.

$ uv init # create a pyproject.toml
$ uv add --group foo pytest
$ uv venv # create venv
$ uv sync --group foo # will install all dependencies, including group "foo"

Michael #3: dive: A tool for exploring each layer in a docker image

via Mike Fiedler
Features:
- Show Docker image contents broken down by layer
- Indicate what's changed in each layer
- Estimate "image efficiency"
- Quick build/analysis cycles
- CI Integration

Brian #4: pytest-metadata

An incredibly useful plugin for adding, you guessed it, metadata, to your pytest results.
Required for pytest-html but also useful on it’s own
Adds metadata to
- text output with --verbose
- xml output when using --junit-xml, handy for CI systems that support junit.xml
Other plugins depend on this and report in other ways, such as pytest-html
By default, already grabs
- Python version
- Platform info
- List of installed packages
- List of installed pytest plugins
You can add your own metadata
You can access all metadata (and add to it) from tests, fixtures, and hook functions via a metadata fixture.
This is in the Top pytest Plugins list, currently #5.

Extras

Brian:

I’ve started filtering deprecated plugins from the pytest plugin list.
I’m also going to start reviewing the list and pulling out interesting plugins as the topic of the next season of Test & Code.

Michael:

Pillow 11 is out
pip install deutschland
Talk Python has a dedicated blog, please subscribe!

Joke: Dog names

#407 Back to the future, destination 3.14

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