From 555a49a36b0a948f581fdfeef76cfec4f121320c Mon Sep 17 00:00:00 2001
From: Martin Lang <martin.lang@mpsd.mpg.de>
Date: Sat, 8 Jun 2024 17:11:00 +0200
Subject: [PATCH] Fix kwarg setup: _checkargs must modify kwargs inplace to
 fulfil assumptions in micromagneticmodel

---
 oommfc/drivers/driver.py           | 10 ++++------
 oommfc/drivers/hysteresisdriver.py | 14 ++++++--------
 oommfc/drivers/mindriver.py        |  2 +-
 oommfc/drivers/timedriver.py       |  1 -
 4 files changed, 11 insertions(+), 16 deletions(-)

diff --git a/oommfc/drivers/driver.py b/oommfc/drivers/driver.py
index 47bdb9d..3403c37 100644
--- a/oommfc/drivers/driver.py
+++ b/oommfc/drivers/driver.py
@@ -21,12 +21,11 @@ def __init__(self, **kwargs):
             self.autoselect_evolver = True
 
     @abc.abstractmethod
-    def _checkargs(self, kwargs) -> dict:
+    def _checkargs(self, kwargs):
         """Check drive keyword arguments.
 
-        This method can also update keyword arguments where required. It must return
-        a dict of all keyword arguments (initial or modified) that shall be used for the
-        simulation.
+        This method can also update keyword arguments where required. Changes must
+        happen in-place, i.e. `kwargs` must be modified directly.
         """
 
     def drive_kwargs_setup(self, drive_kwargs):
@@ -61,12 +60,11 @@ def drive_kwargs_setup(self, drive_kwargs):
             save additional data. Defaults to ``None``.
 
         """
-        drive_kwargs = self._checkargs(drive_kwargs)
+        self._checkargs(drive_kwargs)
         drive_kwargs.setdefault("fixed_subregions", None)
         drive_kwargs.setdefault("output_step", False)
         drive_kwargs.setdefault("n_threads", None)
         drive_kwargs.setdefault("compute", None)
-        return drive_kwargs
 
     def schedule_kwargs_setup(self, schedule_kwargs):
         """Additional keyword arguments allowed for schedule.
diff --git a/oommfc/drivers/hysteresisdriver.py b/oommfc/drivers/hysteresisdriver.py
index 75143ce..f4630fe 100644
--- a/oommfc/drivers/hysteresisdriver.py
+++ b/oommfc/drivers/hysteresisdriver.py
@@ -79,12 +79,12 @@ def _checkargs(self, kwargs):
         if all(item in kwargs for item in ["Hmin", "Hmax", "n"]):
             # case of a symmetric hysteresis simulation
             # construct symmetric Hsteps from (Hmin, Hmax, n)
-            kwargs = {
-                "Hsteps": [
-                    [kwargs["Hmin"], kwargs["Hmax"], kwargs["n"]],
-                    [kwargs["Hmax"], kwargs["Hmin"], kwargs["n"]],
-                ]
-            }
+            kwargs["Hsteps"] = [
+                [kwargs["Hmin"], kwargs["Hmax"], kwargs["n"]],
+                [kwargs["Hmax"], kwargs["Hmin"], kwargs["n"]],
+            ]
+            for key in ["Hmin", "Hmax", "n"]:
+                kwargs.pop(key)
 
         if "Hsteps" in kwargs:
             # case of a stepped hysteresis simulation
@@ -101,8 +101,6 @@ def _checkargs(self, kwargs):
             )
             return ValueError(msg)
 
-        return kwargs
-
     @staticmethod
     def _checkvalues(Hmin, Hmax, n):
         for item in [Hmin, Hmax]:
diff --git a/oommfc/drivers/mindriver.py b/oommfc/drivers/mindriver.py
index a04b9aa..f93fbb7 100644
--- a/oommfc/drivers/mindriver.py
+++ b/oommfc/drivers/mindriver.py
@@ -57,7 +57,7 @@ class MinDriver(Driver):
     ]
 
     def _checkargs(self, kwargs):
-        return kwargs  # no kwargs should be checked
+        pass  # no kwargs should be checked
 
     def _check_system(self, system):
         """Checks the system has energy in it"""
diff --git a/oommfc/drivers/timedriver.py b/oommfc/drivers/timedriver.py
index 3df8070..9f6fff3 100644
--- a/oommfc/drivers/timedriver.py
+++ b/oommfc/drivers/timedriver.py
@@ -66,7 +66,6 @@ def _checkargs(self, kwargs):
         if n <= 0:
             msg = f"Cannot drive with {n=}."
             raise ValueError(msg)
-        return kwargs
 
     def _check_system(self, system):
         """Checks the system has dynamics in it"""