Raise ValueError in attach_subcommand() when the subcommand already e… #883

	# For documentation on GitHub Actions Workflows, see:
	# https://docs.github.com/en/actions/reference/workflow-syntax-for-github-actions
	name: TypeCheck
	on:
	pull_request:
	types: [opened, synchronize, reopened]
	push:
	branches: [main]

	permissions:
	contents: read

	jobs:
	type-check:
	runs-on: ubuntu-latest
	strategy:
	matrix:
	python-version: ["3.10", "3.11", "3.12", "3.13", "3.14"]
	fail-fast: false
	defaults:
	run:
	shell: bash
	steps:
	- name: Check out
	uses: actions/checkout@v6.0.2
	with:
	fetch-depth: 0 # Needed for setuptools_scm to work correctly

	- name: Install uv and set the python version
	uses: astral-sh/setup-uv@v7
	with:
	python-version: ${{ matrix.python-version }}

	- name: Check typing
	run: uv run mypy .

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