fix: Implement Automatic Activation of Virtual Environment in the dev nox session

noxfile.py

@@ -1,6 +1,7 @@
 import nox
 import os
 import sys
+from pathlib import Path
 
 
 # Options to modify nox behaviour
@@ -16,6 +17,7 @@
     "SUNDIALS_INST": f"{homedir}/.local",
     "LD_LIBRARY_PATH": f"{homedir}/.local/lib:",
 }
+VENV_DIR = Path('./venv').resolve()
 
 
 def set_environment_variables(env_dict, session):
@@ -117,8 +119,14 @@ def set_dev(session):
     """Install PyBaMM in editable mode."""
     set_environment_variables(PYBAMM_ENV, session=session)
     envbindir = session.bin
-    session.install("-e", ".[all]", silent=False)
+    session.install("virtualenv")
+    session.run("virtualenv", os.fsdecode(VENV_DIR), silent=True)
+    python = os.fsdecode(VENV_DIR.joinpath("bin/python"))
+    session.run(python, "-m", "pip", "install", "-e", ".[all]", silent=False)
     session.install("cmake", silent=False)
+    session.install("-e", ".[dev]", external=True)
+    if session.platform.startswith("macos") or session.platform.startswith("linux"):
+        session.run(python, "-m", "pip", "install", ".[jax,odes]", silent=False)
     if sys.platform == "linux" or sys.platform == "darwin":
         session.run(
             "echo",