@reducer is here

tests/authoring/test_reducers.py

@@ -0,0 +1,63 @@
+from __future__ import annotations
+
+from pydantic import BaseModel, Field
+
+from wf_authoring import ReducerCatalog, reducer
+from wf_core import ReducerRef
+
+
+class ModuloConfig(BaseModel):
+    modulus: int = Field(gt=0)
+
+
+@reducer(name="wf.std.add")
+def add(current: int | None, incoming: int) -> int:
+    """Add incoming values into integer state."""
+    return (current or 0) + incoming
+
+
+@reducer(name="wf.std.modulo_add", config_model=ModuloConfig)
+def modulo_add(
+    current: int | None,
+    incoming: int,
+    config: ModuloConfig,
+) -> int:
+    """Add incoming values modulo a configured positive integer."""
+    return ((current or 0) + incoming) % config.modulus
+
+
+def test_reducer_decorator_wraps_plain_callable() -> None:
+    assert add.definition.spec.name == "wf.std.add"
+    assert add.definition.spec.description == "Add incoming values into integer state."
+
+    result = add.definition.apply(
+        reducer=ReducerRef(name="wf.std.add"),
+        current_value=2,
+        incoming_value=3,
+        destination_path="state.total",
+    )
+
+    assert result == 5
+
+
+def test_reducer_decorator_wraps_configured_basemodel_callable() -> None:
+    schema = modulo_add.definition.spec.config_schema
+
+    assert schema["properties"]["modulus"]["exclusiveMinimum"] == 0
+
+    result = modulo_add.definition.apply(
+        reducer=ReducerRef(name="wf.std.modulo_add", config={"modulus": 10}),
+        current_value=8,
+        incoming_value=5,
+        destination_path="state.total",
+    )
+
+    assert result == 3
+
+
+def test_reducer_catalog_exposes_definitions_and_specs() -> None:
+    catalog = ReducerCatalog.from_reducers(add, modulo_add)
+
+    assert set(catalog.definitions) == {"wf.std.add", "wf.std.modulo_add"}
+    assert catalog.specs["wf.std.add"].name == "wf.std.add"
+    assert catalog.specs["wf.std.modulo_add"].name == "wf.std.modulo_add"