tox: testenv: use single command, settings via env

Author: blueyed

tox.ini

@@ -35,16 +35,18 @@ setenv =
  COV_CORE_CONFIG={toxinidir}/.coveragerc
  COV_CORE_DATAFILE={toxinidir}/.coverage.eager
 
+ mysql_innodb: DJANGO_SETTINGS_MODULE=pytest_django_test.settings_mysql_innodb
+ mysql_myisam: DJANGO_SETTINGS_MODULE=pytest_django_test.settings_mysql_myisam
+ postgres: DJANGO_SETTINGS_MODULE=pytest_django_test.settings_postgres
+ sqlite: DJANGO_SETTINGS_MODULE=pytest_django_test.settings_sqlite
+ sqlite_file: DJANGO_SETTINGS_MODULE=pytest_django_test.settings_sqlite_file
+
 passenv = PYTEST_ADDOPTS
 usedevelop = True
 commands =
  checkqa: flake8 --version
  checkqa: flake8 --show-source --statistics {posargs:pytest_django pytest_django_test}
- mysql_innodb: pytest --ds=pytest_django_test.settings_mysql_innodb --strict {posargs:tests}
- mysql_myisam: pytest --ds=pytest_django_test.settings_mysql_myisam --strict {posargs:tests}
- postgres: pytest --ds=pytest_django_test.settings_postgres --strict {posargs:tests}
- sqlite: pytest --ds=pytest_django_test.settings_sqlite --strict {posargs:tests}
- sqlite_file: pytest --ds=pytest_django_test.settings_sqlite_file --strict {posargs:tests}
+ pytest --strict {posargs:tests}
 
 [testenv:doc8]
 basepython = python3.6