feat(library): setup ruff and pyright (#7)

This configuration should provide some extra guarantees about code
correctness and formatting and should be VSCode friendly.

Author: bassosimone

.vscode/extensions.json

@@ -0,0 +1,7 @@
+{
+  "recommendations": [
+    "ms-python.python",
+    "ms-python.vscode-pylance",
+    "charliermarsh.ruff"
+  ]
+}

.vscode/settings.json

@@ -0,0 +1,42 @@
+{
+  // Python configuration
+  "python.defaultInterpreterPath": "${workspaceFolder}/.venv/bin/python",
+
+  // Formatting
+  "[python]": {
+    "editor.defaultFormatter": "charliermarsh.ruff",
+    "editor.formatOnSave": true,
+    "editor.codeActionsOnSave": {
+      "source.fixAll": "explicit",
+      "source.organizeImports": "explicit"
+    }
+  },
+
+  // Ruff linter
+  "ruff.enable": true,
+  "ruff.lint.run": "onType",
+  "ruff.organizeImports": true,
+
+  // Type checking (Pylance)
+  "python.analysis.typeCheckingMode": "basic",
+  "python.analysis.autoImportCompletions": true,
+
+  // Testing
+  "python.testing.pytestEnabled": true,
+  "python.testing.unittestEnabled": false,
+  "python.testing.pytestArgs": [
+    "library/tests"
+  ],
+
+  // File associations
+  "files.exclude": {
+    "**/__pycache__": true,
+    "**/*.pyc": true,
+    "**/.pytest_cache": true
+  },
+
+  // Editor settings
+  "editor.rulers": [100],
+  "files.trimTrailingWhitespace": true,
+  "files.insertFinalNewline": true
+}

library/README.md

@@ -61,6 +61,76 @@ uv run pytest tests/iqb_score_test.py::TestIQBInitialization
 uv run pytest tests/iqb_score_test.py::TestIQBInitialization::test_init_with_name
 ```
 
+## Code Quality Tools
+
+The library uses Ruff for linting/formatting and Pyright for type checking.
+
+### Linting with Ruff
+
+Ruff is a fast Python linter that checks code style, potential bugs, and code quality issues:
+
+```bash
+# From the library directory
+cd library
+
+# Check for linting issues
+uv run ruff check .
+
+# Check and auto-fix issues
+uv run ruff check --fix .
+
+# Format code (like Black)
+uv run ruff format .
+
+# Check specific files
+uv run ruff check src/iqb/iqb_score.py
+```
+
+Ruff configuration is in `pyproject.toml` under `[tool.ruff]`.
+
+### Type Checking with Pyright
+
+Pyright performs static type analysis to catch type-related bugs:
+
+```bash
+# From the library directory
+cd library
+
+# Run type checking
+uv run pyright
+
+# Run with verbose output to verify it's checking the right files
+uv run pyright --verbose
+```
+
+**Verifying Pyright is Working:**
+
+Pyright can be silent if misconfigured. To verify it's actually checking your code:
+
+```bash
+# This should show which files are being analyzed
+uv run pyright --verbose
+
+# Expected output should include:
+# - "Loading pyproject.toml file at ..."
+# - "Found X source files" (should be ~5 files)
+# - Python version and search paths
+# - "X errors, Y warnings, Z informations"
+```
+
+If you see "Found 0 source files", the configuration is wrong.
+
+To test that Pyright catches errors, temporarily introduce a type error:
+
+```python
+# In src/iqb/iqb_score.py, add:
+x: int = "this should fail"  # Pyright should catch this!
+```
+
+If Pyright reports an error, it's working correctly. Remove the test line afterwards.
+
+Pyright configuration is in `pyproject.toml` under `[tool.pyright]`.
+
 ## Development
 
 ### Adding New Tests

library/pyproject.toml

@@ -27,6 +27,8 @@ packages = ["src/iqb"]
 [dependency-groups]
 dev = [
     "pytest>=8.0.0",
+    "ruff>=0.8.0",
+    "pyright>=1.1.380",
 ]
 
 [tool.pytest.ini_options]
@@ -39,3 +41,33 @@ addopts = [
     "--strict-markers",
     "--tb=short",
 ]
+
+[tool.ruff]
+line-length = 100
+target-version = "py313"
+
+[tool.ruff.lint]
+select = [
+    "E",   # pycodestyle errors
+    "W",   # pycodestyle warnings
+    "F",   # pyflakes
+    "I",   # isort
+    "N",   # pep8-naming
+    "UP",  # pyupgrade
+    "B",   # flake8-bugbear
+    "C4",  # flake8-comprehensions
+    "SIM", # flake8-simplify
+]
+ignore = [
+    "E501",  # line too long (handled by formatter)
+]
+
+[tool.ruff.lint.isort]
+known-first-party = ["iqb"]
+
+[tool.pyright]
+include = ["src", "tests"]
+exclude = ["**/__pycache__", ".venv"]
+pythonVersion = "3.13"
+typeCheckingMode = "basic"
+reportMissingTypeStubs = false