From 11d2b0250672187ae8a7d3a86aa0dc417d2aaaab Mon Sep 17 00:00:00 2001
From: Callum Forrester <callum.forrester@diamond.ac.uk>
Date: Mon, 11 Aug 2025 14:57:47 +0000
Subject: [PATCH] Enable pep8-naming ruff rules

Fixes #282

Enable pep8-naming ruff rules, enforcing that projects follow convetional pep8 naming styles. See https://peps.python.org/pep-0008
---
 pyproject.toml                |  7 +++++++
 template/pyproject.toml.jinja |  1 +
 tests/test_example.py         | 15 +++++++++++++++
 3 files changed, 23 insertions(+)

diff --git a/pyproject.toml b/pyproject.toml
index b0ab7390..47c023b2 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -62,7 +62,14 @@ lint.select = [
     "C4", # flake8-comprehensions - https://docs.astral.sh/ruff/rules/#flake8-comprehensions-c4
     "E",  # pycodestyle errors - https://docs.astral.sh/ruff/rules/#error-e
     "F",  # pyflakes rules - https://docs.astral.sh/ruff/rules/#pyflakes-f
+    "N",  # pep8-naming - https://docs.astral.sh/ruff/rules/#pep8-naming-n
     "W",  # pycodestyle warnings - https://docs.astral.sh/ruff/rules/#warning-w
     "I",  # isort - https://docs.astral.sh/ruff/rules/#isort-i
     "UP", # pyupgrade - https://docs.astral.sh/ruff/rules/#pyupgrade-up
 ]
+
+[tool.ruff.lint.per-file-ignores]
+# Ignore variable names inside the template because ruff doesn't 
+# work well with jinja templating. Any violations of N rules inside
+# the template are caught by the tests.
+"template/**/*" = ["N"]
diff --git a/template/pyproject.toml.jinja b/template/pyproject.toml.jinja
index 2155ca29..8623ebb3 100644
--- a/template/pyproject.toml.jinja
+++ b/template/pyproject.toml.jinja
@@ -109,6 +109,7 @@ lint.select = [
     "C4",  # flake8-comprehensions - https://docs.astral.sh/ruff/rules/#flake8-comprehensions-c4
     "E",   # pycodestyle errors - https://docs.astral.sh/ruff/rules/#error-e
     "F",   # pyflakes rules - https://docs.astral.sh/ruff/rules/#pyflakes-f
+    "N",   # pep8-naming - https://docs.astral.sh/ruff/rules/#pep8-naming-n
     "W",   # pycodestyle warnings - https://docs.astral.sh/ruff/rules/#warning-w
     "I",   # isort - https://docs.astral.sh/ruff/rules/#isort-i
     "UP",  # pyupgrade - https://docs.astral.sh/ruff/rules/#pyupgrade-up
diff --git a/tests/test_example.py b/tests/test_example.py
index cd672391..2608b0e7 100644
--- a/tests/test_example.py
+++ b/tests/test_example.py
@@ -223,6 +223,21 @@ def __init__(self):
         run("ruff check")
 
 
+def test_pep8_naming(tmp_path: Path):
+    code = """
+myVariable = "foo"
+"""
+
+    copy_project(tmp_path)
+    run = make_venv(tmp_path)
+
+    src_file = tmp_path / "src" / "python_copier_template_example" / "bad_example.py"
+    with src_file.open("w") as stream:
+        stream.write(code)
+    with pytest.raises(AssertionError, match=r"N816 .*"):
+        run("ruff check")
+
+
 def test_pyright_works_in_standard_typing_mode(tmp_path: Path):
     copy_project(tmp_path, type_checker="pyright", strict_typing=False)
     pyproject_toml = tmp_path / "pyproject.toml"