Add ttd directive

multiple_python_version/Makefile

@@ -18,7 +18,6 @@ py_install=$(python) -m pip
 
 test: venv
 	$(pytest) --version || make install
-
 	$(pytest) -sv --durations=5 --ignore-glob=sample_* .
 
 qtest: venv
@@ -29,6 +28,7 @@ install_dependencies:
 	$(py_install) install -U pip wheel
 	$(py_install) install pytest python-dotenv pytest-icdiff
 
+install: venv install_dependencies
 
 venv:
 	make .venv3.$(minor)
@@ -36,7 +36,9 @@ venv:
 clean:
 	rm -fr $(venv)
 
-install: venv install_dependencies
+tdd:
+	ls | entr -d make test
+
 build: install test
 scratch: clean install test