Switch formatter

.github/CONTRIBUTING.md

@@ -137,8 +137,10 @@ But it's way more comfortable to run it locally and catch avoidable errors befor
           A very important return value.
       """
   ```
+
 - If you add or change public APIs, tag the docstring using `..  versionadded:: 16.0.0 WHAT` or `..  versionchanged:: 16.2.0 WHAT`.
-- We use [Ruff](https://ruff.rs/) to sort our imports, and we use [Black](https://github.com/psf/black) with line length of 79 characters to format our code.
+
+- We follow [PEP 8](https://peps.python.org/pep-0008/) as enforced by [Ruff](https://ruff.rs/) with a line length of 79 characters.
   As long as you run our full [*tox*] suite before committing, or install our [*pre-commit*] hooks (ideally you'll do both – see [*Local Development Environment*](#local-development-environment) above), you won't have to spend any time on formatting your code at all.
   If you don't, [CI] will catch it for you – but that seems like a waste of your time!
 

.pre-commit-config.yaml

@@ -1,15 +1,11 @@
 ---
 repos:
-  - repo: https://github.com/psf/black
-    rev: 24.4.2
-    hooks:
-      - id: black
-
   - repo: https://github.com/astral-sh/ruff-pre-commit
-    rev: v0.5.4
+    rev: v0.7.1
     hooks:
       - id: ruff
         args: [--fix, --exit-non-zero-on-fix]
+      - id: ruff-format
 
   - repo: https://github.com/codespell-project/codespell
     rev: v2.3.0
@@ -24,7 +20,7 @@ repos:
         args: [tests]
 
   - repo: https://github.com/pre-commit/pre-commit-hooks
-    rev: v4.6.0
+    rev: v5.0.0
     hooks:
       - id: trailing-whitespace
       - id: end-of-file-fixer

pyproject.toml

@@ -132,12 +132,9 @@ fail-under = 100
 whitelist-regex = ["test_.*"]
 
 
-[tool.black]
-line-length = 79
-
-
 [tool.ruff]
 src = ["src", "tests"]
+line-length = 79
 
 [tool.ruff.lint]
 select = ["ALL"]
@@ -146,11 +143,12 @@ ignore = [
     "ANN",     # Mypy is better at this
     "ARG001",  # we don't control all args passed in
     "ARG005",  # we need stub lambdas
-    "COM",     # Black takes care of our commas
+    "COM",     # ruff format takes care of our commas
     "D",       # We prefer our own docstring style.
-    "E501",    # leave line-length enforcement to Black
+    "E501",    # leave line-length enforcement to ruff format
     "FIX",     # Yes, we want XXX as a marker.
     "INP001",  # sometimes we want Python files outside of packages
+    "ISC001",  # conflicts with ruff format
     "N801",    # some artistic freedom when naming things after RFCs
     "N802",    # ditto
     "PLR2004", # numbers are sometimes fine
@@ -183,6 +181,7 @@ lines-after-imports = 2
 
 [tool.mypy]
 strict = true
+pretty = true
 
 show_error_codes = true
 enable_error_code = ["ignore-without-code"]