'make test' and 'make install-test' independent

Makefile

@@ -58,7 +58,8 @@ install-test: compile
 	pip3 install .[test]
 
 # TODO: maybe use setup.py test?
-test: install-test
+# --forked, because every test needs a separate process, see PYADPT-100
+test:
 	pytest --forked
 
 

docs/source/install.rst

@@ -73,12 +73,16 @@ To install the extension module into your home dir, use:
 
 Test
 ----
-To run the whole testsuite you need to create/activate the venv, and then invoke the make target 'test'.
+To run the whole testsuite you need to first create/activate the venv:
-You can do this from a clean clone of the repo, no prior actions required, the whole module and all dependencies
-will be compiled and installed into the venv.
 
 ``make venv``
 
+then install the test-dependencies:
+
+``make install-test``
+
+And finally run the test-suite:
+
 ``make test``