Adding a warning if there is a conflict between env vars and arguments (

#2913)

* Avoiding having both "start_instance" and "ip" set.
Adding tests

* Adding warnings if there is a conflict between env vars and arguments

* Update src/ansys/mapdl/core/launcher.py

Co-authored-by: Camille <78221213+clatapie@users.noreply.github.com>

---------

Co-authored-by: Camille <78221213+clatapie@users.noreply.github.com>

src/ansys/mapdl/core/launcher.py

@@ -799,9 +799,19 @@ def get_start_instance(start_instance: bool = True):
         Raised when ``PYMAPDL_START_INSTANCE`` is not either true or false
         (case independent).
 
+    Notes
+    -----
+    If the environment variable ``PYMAPDL_START_INSTANCE`` is set,
+    hence the argument ``start_instance`` is overwritten.
+
     """
     if "PYMAPDL_START_INSTANCE" in os.environ and os.environ["PYMAPDL_START_INSTANCE"]:
         # It should not be empty
+        if isinstance(start_instance, bool):
+            warnings.warn(
+                "The environment variable 'PYMAPDL_START_INSTANCE' is set, "
+                "hence the argument 'start_instance' is overwritten."
+            )
         start_instance = os.environ["PYMAPDL_START_INSTANCE"]
     else:
         LOG.debug(
@@ -1475,6 +1485,11 @@ def launch_mapdl(
     # Getting IP from env var
     ip_env_var = os.environ.get("PYMAPDL_IP", "")
     if ip_env_var != "":
+        if ip:
+            warnings.warn(
+                "The env var 'PYMAPDL_IP' is set, hence the 'ip' argument is overwritten."
+            )
+
         ip = ip_env_var
         LOG.debug(f"An IP ({ip}) has been set using 'PYMAPDL_IP' env var.")
 

tests/test_launcher.py

@@ -25,6 +25,7 @@
 import os
 import tempfile
 from time import sleep
+import warnings
 
 import psutil
 import pytest
@@ -648,7 +649,18 @@ def test_ip_and_start_instance(
 
         return  # Exit
 
-    options = launch_mapdl(start_instance=start_instance, ip=ip, _debug_no_launch=True)
+    if (
+        isinstance(start_instance_envvar, bool) and isinstance(start_instance, bool)
+    ) or (ip_envvar and ip):
+        with pytest.warns(UserWarning):
+            options = launch_mapdl(
+                start_instance=start_instance, ip=ip, _debug_no_launch=True
+            )
+    else:
+        with warnings.catch_warnings():
+            options = launch_mapdl(
+                start_instance=start_instance, ip=ip, _debug_no_launch=True
+            )
 
     if start_instance_envvar is True:
         assert options["start_instance"] is True