Validate systems, components and mapping when creating protocol

.github/workflows/rc-test.yaml

@@ -23,7 +23,7 @@ defaults:
 jobs:
   tests:
     runs-on: ${{ matrix.os }}-latest
-    name: "💻-${{matrix.os }} 🐍-${{ matrix.python-version }}"
+    name: "💻-${{matrix.os }} 🐍-${{ matrix.python-version }} OpenFE RC"
     strategy:
       fail-fast: false
       matrix:

feflow/protocols/nonequilibrium_cycling.py

@@ -913,15 +913,27 @@ def _create(
         self,
         stateA: ChemicalSystem,
         stateB: ChemicalSystem,
-        mapping: Optional[dict[str, ComponentMapping]] = None,
+        mapping: Optional[ComponentMapping],
         extends: Optional[ProtocolDAGResult] = None,
     ) -> list[ProtocolUnit]:
-        # Handle parameters
-        if mapping is None:
-            raise ValueError("`mapping` is required for this Protocol")
+        from feflow.utils import system_validation
+
+        # TODO: enable extending https://github.com/choderalab/feflow/pull/44
         if extends:
             raise NotImplementedError("Can't extend simulations yet")
 
+        # TODO: Validate mapping -- comps gufe keys are the same
+        system_validation.validate_mappings(stateA, stateB, mapping)
+
+        # Validate alchemical components
+        alchem_comps = system_validation.get_alchemical_components(stateA, stateB)
+        system_validation.validate_alchemical_components(alchem_comps, mapping)
+
+        # Validate protein and solvent components
+        system_validation.validate_protein(stateA)
+        nonbonded = self.settings.forcefield_settings.nonbonded_method
+        system_validation.validate_solvent(stateA, nonbonded)
+
         # inputs to `ProtocolUnit.__init__` should either be `Gufe` objects
         # or JSON-serializable objects
         num_cycles = self.settings.num_cycles

feflow/utils/system_validation.py

@@ -0,0 +1,31 @@
+"""
+Utility functions that can help validating chemical systems and its components such that they
+make sense for protocols to use.
+"""
+
+# TODO: Migrate utility functions from openfe to this module
+from openfe.protocols.openmm_utils.system_validation import (
+    get_alchemical_components as _ofe_get_alchemical_components,
+)
+from openfe.protocols.openmm_utils.system_validation import (
+    validate_solvent as _ofe_validate_solvent,
+)
+from openfe.protocols.openmm_utils.system_validation import (
+    validate_protein as _ofe_validate_protein,
+)
+from openfe.protocols.openmm_rfe.equil_rfe_methods import (
+    _validate_alchemical_components,
+)
+
+get_alchemical_components = _ofe_get_alchemical_components
+validate_solvent = _ofe_validate_solvent
+validate_protein = _ofe_validate_protein
+validate_alchemical_components = _validate_alchemical_components
+
+
+# TODO: Implement function to validate mappings -- comps are the same gufe key compared to state
+def validate_mappings(state_a, state_b, mapping):
+    """
+    Validate that the components in the states and the mapping are the correct ones.
+    """
+    raise NotImplementedError("Function not implemented.")