Enforce f-string interpolation with Ruff

- Adds a pre-commit hook for ungoing enforcement.
- --force-exclude prevents generated migrations from causing problems.

Author: markstos

.pre-commit-config.yaml

@@ -0,0 +1,8 @@
+repos:
+  - repo: local
+    hooks:
+      - id: ruff-check
+        name: ruff check
+        entry: uv run ruff check --fix --force-exclude
+        language: system
+        types_or: [python, pyi]

README.md

@@ -68,6 +68,19 @@ These can be installed be appending `--extra <optional dependency>` like so:
 uv sync --extra cli --extra docs --extra subscription
 ```
 
+## Python linting
+
+Ruff is the source of truth for Python linting. Read `pyproject.toml` and `pulumi/ruff.toml` for the active
+rules; local pre-commit hooks and CI run Ruff against those configs.
+
+To install and run the local pre-commit hook:
+
+```bash
+uv tool install pre-commit
+pre-commit install
+pre-commit run --all-files
+```
+
 ## Re-bootstrapping the project
 
 If you find your environment in a troubled state (it happens) you can add the option `--from-scratch` to bootstrap like

pulumi/ruff.toml

@@ -20,7 +20,9 @@ quote-style = "single"
 
 [lint]
 # Enable pycodestyle (`E`) and Pyflakes (`F`) codes by default.
-select = ["E", "F"]
+# Require f-strings for interpolation instead of printf-style formatting (UP031)
+# or `.format` calls (UP032).
+select = ["E", "F", "UP031", "UP032"]
 ignore = []
 
 # Allow autofix for all enabled rules (when `--fix`) is provided.

pyproject.toml

@@ -131,7 +131,9 @@ quote-style = "single"
 [tool.ruff.lint]
 # Enable pycodestyle (`E`) and Pyflakes (`F`) codes by default.
 # Enable flagging print (T201)
-select = ["E", "F", "T201"]
+# Require f-strings for interpolation instead of printf-style formatting (UP031)
+# or `.format` calls (UP032).
+select = ["E", "F", "T201", "UP031", "UP032"]
 ignore = []
 
 # Allow autofix for all enabled rules (when `--fix`) is provided.

src/thunderbird_accounts/authentication/middleware.py

@@ -441,7 +441,7 @@ def _prepare_reauthorization(self, request):
         request.session['oidc_login_next'] = request.get_full_path()
 
         query = urlencode(params, quote_via=quote)
-        return '{auth_url}?{query}'.format(auth_url=auth_url, query=query)
+        return f'{auth_url}?{query}'
 
 
 class SetHostIPInAllowedHostsMiddleware: