Slightly more dodgy but more robust test dependency installation script

src/blenderbim/docs/devs/running_tests.rst

@@ -6,7 +6,8 @@ Running tests
 The BlenderBIM Add-on has three layers of tests for each of its three technology
 layers. These roughly form a test pyramid, moving from many abstract domain
 logic tests, to low-level concrete unit tests, to a minimal number of UI and
-smoke tests. These tests use ``pytest`` as the test framework and runner.
+smoke tests. These tests use ``pytest`` as the test framework and runner, so you
+will need to install ``pytest``.
 
 All development is expected to use test driven development, and so we expect
 test coverage to be 100% where it is technically possible to test.
@@ -39,8 +40,8 @@ similar.
 Tool tests
 ----------
 
-The tool layer tests actual concrete functions. These have the following
-dependencies:
+The tool layer tests actual concrete functions. You will need to install the
+following dependencies:
 
 * pytest-blender, accessible to your system's Python
 * Blender executable, accessible to pytest-blender on your system's Python
@@ -51,6 +52,16 @@ dependencies:
 You can install the dependencies by running the ``scripts/setup_pytest.py``
 script in Blender.
 
+.. warning::
+
+   The ``scripts/setup_pytest.py`` may not work for all operating systems and
+   installation environments. In this case, you may be required to install the
+   dependencies manually.
+
+   Please be aware that some Blender may come packaged with its own Python,
+   which may be separate to the Python installation on your system. Be sure to
+   install the dependencies to the correct Python environment.
+
 Then, run the tests. This will launch Blender headlessly and check the behaviour
 of all concrete functions.
 

src/blenderbim/scripts/setup_pytest.py

@@ -16,16 +16,40 @@
 # You should have received a copy of the GNU General Public License
 # along with BlenderBIM Add-on.  If not, see <http://www.gnu.org/licenses/>.
 
-import subprocess
 import sys
-from pathlib import Path
+import subprocess
+
+print("Here are the detected system paths:")
+print(sys.path)
 
 py_exec = str(sys.executable)
-lib = Path(py_exec).parent.parent / "lib" 
+
+print("Detected executable:", py_exec)
 
 subprocess.call([py_exec, "-m", "ensurepip", "--user"])
-subprocess.call([py_exec, "-m", "pip", "install", "--upgrade",  "pip"])
-subprocess.call([py_exec, "-m", "pip", "install", f"--target={str(lib)}", "pytest"])
-subprocess.call([py_exec, "-m", "pip", "install", f"--target={str(lib)}", "pytest-blender"])
-subprocess.call([py_exec, "-m", "pip", "install", f"--target={str(lib)}", "pytest-bdd"])
-subprocess.call([py_exec, "-m", "pip", "install", f"--target={str(lib)}", "pygments"])
+subprocess.call([py_exec, "-m", "pip", "install", "--upgrade", "pip"])
+
+sys_paths = [p for p in sys.path if "site-packages" in p]
+if sys_paths:
+    print("Detected installation directory:", sys_paths[-1])
+    subprocess.call([py_exec, "-m", "pip", "install", f"--target={sys_paths[-1]}", "pytest"])
+    subprocess.call([py_exec, "-m", "pip", "install", f"--target={sys_paths[-1]}", "pytest-bdd"])
+    subprocess.call([py_exec, "-m", "pip", "install", f"--target={sys_paths[-1]}", "pytest-blender"])
+    subprocess.call([py_exec, "-m", "pip", "install", f"--target={sys_paths[-1]}", "pygments"])
+else:
+    print("Could not detect installation directory. Good luck.")
+    subprocess.call([py_exec, "-m", "pip", "install", "pytest"])
+    subprocess.call([py_exec, "-m", "pip", "install", "pytest-bdd"])
+    subprocess.call([py_exec, "-m", "pip", "install", "pytest-blender"])
+    subprocess.call([py_exec, "-m", "pip", "install", "pygments"])
+
+try:
+    import pytest
+    import pytest_bdd
+    import pytest_blender
+    import pygments
+
+    print("Test dependency installation was successful!")
+except Exception as e:
+    print("Installation failed :(")
+    print(e)