Patch domain checks to only happen once

ndsl/dsl/stencil.py

@@ -290,6 +290,8 @@ def __init__(
         else:
             self._timing_collector = timing_collector
 
+        self._arguments_already_checked = False
+
         if externals is None:
             externals = {}
         self.externals = externals
@@ -406,7 +408,11 @@ def __call__(self, *args: Any, **kwargs: Any) -> None:
         if self.stencil_config.verbose:
             ndsl_log.debug(f"Running {self._func_name}")
 
-        self._validate_quantity_sizes(*args, **kwargs)
+        if (
+            not self._arguments_already_checked
+            and self.stencil_config.compilation_config.validate_args
+        ):
+            self._validate_quantity_sizes(*args, **kwargs)
 
         # Marshal arguments
         args_list = list(args)
@@ -430,7 +436,10 @@ def __call__(self, *args: Any, **kwargs: Any) -> None:
             ndsl_debugger.track_data(all_args, self._func_qualname, is_in=True)
 
         # Execute stencil
-        if self.stencil_config.compilation_config.validate_args:
+        if (
+            not self._arguments_already_checked
+            and self.stencil_config.compilation_config.validate_args
+        ):
             if __debug__ and "origin" in kwargs:
                 raise TypeError("origin cannot be passed to FrozenStencil call")
             if __debug__ and "domain" in kwargs:
@@ -443,6 +452,7 @@ def __call__(self, *args: Any, **kwargs: Any) -> None:
                 validate_args=True,
                 exec_info=self._timing_collector.exec_info,
             )
+            self._arguments_already_checked = True
         else:
             self.stencil_object.run(
                 **args_as_kwargs,

tests/dsl/test_stencil.py

@@ -156,3 +156,28 @@ def test_stencil_2D_temporaries() -> None:
     )
     stencil(quantity)
     assert (quantity.data[1, 1, :] == 21.0).all()
+
+
+@pytest.mark.parametrize(
+    "iterations",
+    [2, 1],
+)
+def test_validation_call_count(iterations: tuple[int]):
+    domain = (2, 2, 5)
+    quantity = Quantity(np.zeros(domain), ["x", "y", "z"], "n/a", extent=domain)
+    stencil_config = StencilConfig(
+        compilation_config=CompilationConfig(backend="numpy", rebuild=True)
+    )
+    stencil = FrozenStencil(
+        copy_stencil,
+        origin=(0, 0, 0),
+        domain=domain,
+        stencil_config=stencil_config,
+    )
+    # with expectation:
+    counting_mock = MagicMock()
+    with patch.object(FrozenStencil, "_validate_quantity_sizes", counting_mock):
+        for _i in range(iterations):
+            stencil(quantity, quantity)
+
+    assert counting_mock.call_count == 1