Allow passing of Python objects in the parameters dict

petsctools/options.py

@@ -1,10 +1,12 @@
 from __future__ import annotations
 
-import weakref
 import contextlib
 import functools
 import itertools
+import numbers
+import types
 import warnings
+import weakref
 from functools import cached_property
 from typing import Any, Iterable
 
@@ -280,6 +282,15 @@ def get_default_options(default_options_set: DefaultOptionSet,
     return default_options
 
 
+_native_petsc_option_types = (
+    bool,
+    str,
+    types.NoneType,
+    numbers.Number,
+)
+"""Types that are allowed to be directly passed as PETSc options."""
+
+
 class OptionsManager:
     """Class that helps with managing setting PETSc options.
 
@@ -419,6 +430,14 @@ def __init__(self, parameters: dict,
             # Convert nested dicts
             parameters = flatten_parameters(parameters)
 
+        if appmngr is None:
+            appmngr = AppContextManager()
+
+        # Replace any Python objects in the parameters dict with appctx entries
+        for key, value in parameters.items():
+            if not isinstance(value, _native_petsc_option_types):
+                parameters[key] = appmngr.add(value)
+
         # If no prefix is provided generate a default prefix
         # and ignore any command line options
         if options_prefix is None:

tests/test_appctx.py

@@ -26,7 +26,8 @@ def apply(self, pc, x, y):
 
 @pytest.mark.skipnopetsc4py
 @pytest.mark.parametrize("use_prefix", ["with_prefix", "without_prefix"])
-def test_appctx_context_manager(use_prefix):
+@pytest.mark.parametrize("implicit_appmngr", [False, True])
+def test_appctx_context_manager(use_prefix, implicit_appmngr):
     PETSc = petsctools.init()
     n = 4
     sizes = (n, n)
@@ -40,19 +41,21 @@ def test_appctx_context_manager(use_prefix):
     ksp = PETSc.KSP().create()
     ksp.setOperators(mat, mat)
 
-    appmngr = petsctools.AppContextManager()
+    parameters = {
+        'ksp_type': 'preonly',
+        'pc_type': 'python',
+        'pc_python_type': f'{__name__}.JacobiTestPC',
+        'jacobi_use_prefixed_appctx': use_prefix == "with_prefix",
+    }
+    if implicit_appmngr:
+        appmngr = None
+        parameters['jacobi_scale'] = diag
+    else:
+        appmngr = petsctools.AppContextManager()
+        parameters['jacobi_scale'] = appmngr.add(diag)
 
     petsctools.set_from_options(
-        ksp,
-        parameters={
-            'ksp_type': 'preonly',
-            'pc_type': 'python',
-            'pc_python_type': f'{__name__}.JacobiTestPC',
-            'jacobi_scale': appmngr.add(diag),
-            'jacobi_use_prefixed_appctx': use_prefix == "with_prefix",
-        },
-        options_prefix="myksp",
-        appmngr=appmngr,
+        ksp, parameters=parameters, options_prefix="myksp", appmngr=appmngr
     )
 
     x, b = mat.createVecs()