Fix an unexpected exception when using dsn without username & password #260

	name: mycli

	on:
	pull_request:
	paths-ignore:
	- '**.md'

	jobs:
	linux:
	strategy:
	matrix:
	python-version: [
	'3.7',
	'3.8',
	'3.9',
	'3.10',
	]
	include:
	- python-version: '3.7'
	os: ubuntu-18.04 # MySQL 5.7.32
	- python-version: '3.8'
	os: ubuntu-18.04 # MySQL 5.7.32
	- python-version: '3.9'
	os: ubuntu-20.04 # MySQL 8.0.22
	- python-version: '3.10'
	os: ubuntu-22.04 # MySQL 8.0.28

	runs-on: ${{ matrix.os }}
	steps:

	- uses: actions/checkout@v2

	- name: Set up Python ${{ matrix.python-version }}
	uses: actions/setup-python@v2
	with:
	python-version: ${{ matrix.python-version }}

	- name: Start MySQL
	run: \|
	sudo /etc/init.d/mysql start

	- name: Install dependencies
	run: \|
	python -m pip install --upgrade pip
	pip install -r requirements-dev.txt
	pip install --no-cache-dir -e .

	- name: Wait for MySQL connection
	run: \|
	while ! mysqladmin ping --host=localhost --port=3306 --user=root --password=root --silent; do
	sleep 5
	done

	- name: Pytest / behave
	env:
	PYTEST_PASSWORD: root
	PYTEST_HOST: 127.0.0.1
	run: \|
	./setup.py test --pytest-args="--cov-report= --cov=mycli"

	- name: Lint
	run: \|
	./setup.py lint --branch=HEAD

	- name: Coverage
	run: \|
	coverage combine
	coverage report

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