component filename, default fmt ascii, revert sim path -> workspace

Author: wpbonelli

docs/examples/quickstart.py

@@ -13,7 +13,7 @@
 workspace = Path(__file__).parent / name
 time = ModelTime(perlen=[1.0], nstp=[1])
 grid = StructuredGrid(nlay=1, nrow=10, ncol=10)
-sim = Simulation(name=name, path=workspace, tdis=time)
+sim = Simulation(name=name, workspace=workspace, tdis=time)
 ims = Ims(parent=sim)
 gwf_name = "mymodel"
 gwf = Gwf(parent=sim, name=gwf_name, save_flows=True, dis=grid)

docs/examples/quickstart_expanded.py

@@ -31,7 +31,7 @@
 
 ws = "./mymodel"
 name = "mymodel"
-sim = Simulation(name=name, path=ws, exe="mf6")
+sim = Simulation(name=name, workspace=ws, exe="mf6")
 tdis = Tdis(sim)
 gwf = Gwf(sim, name=name, save_flows=True)
 dis = Dis(gwf, nrow=10, ncol=10)

flopy4/mf6/__init__.py

@@ -7,8 +7,8 @@
 
 def _default_filename(component: Component) -> str:
     """Default path for a component, based on its name."""
-    if hasattr(component, "filename") and component.filename is not None:
-        return component.filename
+    if filename := component.filename:
+        return filename
     name = component.name  # type: ignore
     cls_name = component.__class__.__name__.lower()
     return f"{name}.{cls_name}"

flopy4/mf6/component.py

@@ -4,14 +4,16 @@
 from modflow_devtools.dfn import Dfn, Field
 from xattree import xattree
 
-from flopy4.mf6.spec import fields_dict, to_dfn_field
+from flopy4.mf6.spec import field, fields_dict, to_dfn_field
 from flopy4.uio import IO, Loader, Writer
 
 COMPONENTS = {}
 """MF6 component registry."""
 
 
-@xattree
+# kw_only=True necessary so we can define optional fields here
+# and required fields in subclasses. attrs complains otherwise
+@xattree(kw_only=True)
 class Component(ABC, MutableMapping):
     """
     Base class for MF6 components.
@@ -22,11 +24,14 @@ class Component(ABC, MutableMapping):
 
     We use the `children` attribute provided by `xattree`. We know
     children are also `Component`s, but mypy does not. TODO: fix??
+    Then we can remove the `# type: ignore` comments.
     """
 
     _load = IO(Loader)  # type: ignore
     _write = IO(Writer)  # type: ignore
 
+    filename: str = field(default=None)
+
     @classmethod
     def __attrs_init_subclass__(cls):
         COMPONENTS[cls.__name__.lower()] = cls
@@ -49,13 +54,14 @@ def __len__(self):
 
     @classmethod
     def get_dfn(cls) -> Dfn:
+        """Generate the component's MODFLOW 6 definition."""
         fields = {field_name: to_dfn_field(field) for field_name, field in fields_dict(cls).items()}
         blocks: dict[str, dict[str, Field]] = {}
-        for field_name, field in fields.items():
-            if (block := field.get("block", None)) is not None:
-                blocks.setdefault(block, {})[field_name] = field
+        for field_name, field_ in fields.items():
+            if (block := field_.get("block", None)) is not None:
+                blocks.setdefault(block, {})[field_name] = field_
             else:
-                blocks[field_name] = field
+                blocks[field_name] = field_
 
         return Dfn(
             name=cls.__name__.lower(),

flopy4/mf6/exchange.py

@@ -1,3 +1,4 @@
+from abc import ABC
 from pathlib import Path
 from typing import Optional
 
@@ -7,8 +8,10 @@
 
 
 @xattree
-class Exchange(Package):
-    exgtype: type = field()
-    exgfile: Path = field()
+class Exchange(Package, ABC):
+    # mypy doesn't understand that kw_only=True on the
+    # Component means we can have required fields here
+    exgtype: type = field()  # type: ignore
+    exgfile: Path = field()  # type: ignore
     exgmnamea: Optional[str] = field(default=None)
     exgmnameb: Optional[str] = field(default=None)

flopy4/mf6/simulation.py

@@ -1,15 +1,16 @@
 from os import PathLike
 from pathlib import Path
-from typing import ClassVar
+from warnings import warn
 
 from flopy.discretization.modeltime import ModelTime
 from modflow_devtools.misc import cd, run_cmd
-from xattree import field, xattree
+from xattree import xattree
 
 from flopy4.mf6.component import Component
 from flopy4.mf6.exchange import Exchange
 from flopy4.mf6.model import Model
 from flopy4.mf6.solution import Solution
+from flopy4.mf6.spec import field
 from flopy4.mf6.tdis import Tdis
 
 
@@ -27,31 +28,49 @@ class Simulation(Component):
     exchanges: dict[str, Exchange] = field()
     solutions: dict[str, Solution] = field()
     tdis: Tdis = field(converter=convert_time)
-    # TODO: decorator for components bound
-    # to some directory or file path?
-    path: Path = field(default=None)
-    filename: ClassVar[str] = "mfsim.nam"
+    workspace: Path = field(default=None)
+    filename: str = field(default="mfsim.nam")
+
+    def __attrs_post_init__(self):
+        """Post-initialization hook to set up the simulation."""
+        super().__attrs_post_init__()
+        if self.filename != "mfsim.nam":
+            warn(
+                "Simulation filename must be 'mfsim.nam'.",
+                UserWarning,
+            )
+            self.filename = "mfsim.nam"
+
+    @property
+    def path(self) -> Path:
+        """Return the path to the simulation namefile."""
+        if self.workspace is None:
+            raise ValueError("Simulation has no workspace path.")
+        return Path(self.workspace).expanduser().resolve() / self.filename
 
     @property
     def time(self) -> ModelTime:
+        """Return the simulation time discretization."""
         return self.tdis.to_time()
 
     def run(self, exe: str | PathLike = "mf6", verbose: bool = False) -> None:
         """Run the simulation using the given executable."""
-        if self.path is None:
+        if self.workspace is None:
             raise ValueError(f"Simulation {self.name} has no workspace path.")
-        with cd(self.path):
+        with cd(self.workspace):
             stdout, stderr, retcode = run_cmd(exe, verbose=verbose)
             if retcode != 0:
                 raise RuntimeError(
                     f"Simulation {self.name}: {exe} failed to run with returncode "  # type: ignore
                     f"{retcode}, and error message:\n\n{stdout + stderr} "
                 )
 
-    def load(self, format):
-        with cd(self.path):
+    def load(self, format="ascii"):
+        """Load the simulation in the specified format."""
+        with cd(self.workspace):
             super().load(format)
 
-    def write(self, format):
-        with cd(self.path):
+    def write(self, format="ascii"):
+        """Write the simulation in the specified format."""
+        with cd(self.workspace):
             super().write(format)