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Brian #1: Coverage.py regex pragmas
Ned Batchelder
The regex implementation of how coverage.py recognizes pragmas is pretty amazing.
It’s extensible through plugins
- covdefaults adds a bunch of default exclusions, and also platform- and version-specific comment syntaxes.
- coverage-conditional-plugin gives you a way to create comment syntaxes for entire files, for whether other packages are installed, and so on.
A change from last year (as part of coverage.py 7.6 allows multiline regexes, which let’s us do things like:
- Exclude an entire file with
\\A(?s:.*# pragma: exclude file.*)\\Z
- Allow start and stop delimiters with
# no cover: start(?s:.*?)# no cover: stop
- Exclude empty placeholder methods with
^\\s*(((async )?def .*?)?\\)(\\s*->.*?)?:\\s*)?\\.\\.\\.\\s*(#|$)
- See Ned’s article for explanations of these
Michael #2: Python of Yore
- via Matthias
- Use
YORE: ... comments to highlight CPython version dependencies.
# YORE: EOL 3.8: Replace block with line 4.
if sys.version_info < (3, 9):
from astunparse import unparse
else:
from ast import unparse
Then check when they go out of support:
$ yore check --eol-within '5 months'
./src/griffe/agents/nodes/_values.py:11: Python 3.8 will reach its End of Life within approx. 4 months
Even fix them with fix .
Michael #3: nox-uv
- via John Hagen
- What nox-uv does is make it very simple to install uv extras and/or dependency groups into a nox session's virtual environment.
- The versions installed are constrained by uv's lockfile meaning that everything is deterministic and pinned.
- Dependency groups make it very easy to install only want is necessary for a session (e.g., only linting dependencies like Ruff, or main dependencies + mypy for type checking).
Brian #4: A couple Django items
- Stop Using Django's squashmigrations: There's a Better Way
- Johnny Metz
- Resetting migrations is sometimes the right thing.
- Overly simplified summary: delete migrations and start over
- dj-lite
- Adam Hill
- Use SQLite in production with Django
- “Simplify deploying and maintaining production Django websites by using SQLite in production.
dj-lite helps enable the best performance for SQLite for small to medium-sized projects. It requires Django 5.1+.”
Extras
Brian:
Michael:
Joke: Copy/Paste
