Streamline LinkableSpecSet.create_from_specs() to avoid circular im…

…ports.

metricflow-semantics/metricflow_semantics/specs/linkable_spec_set.py

@@ -1,5 +1,6 @@
 from __future__ import annotations
 
+import dataclasses
 import itertools
 import typing
 from dataclasses import dataclass
@@ -13,13 +14,15 @@
 from metricflow_semantics.specs.dimension_spec import DimensionSpec
 from metricflow_semantics.specs.entity_spec import EntitySpec
 from metricflow_semantics.specs.group_by_metric_spec import GroupByMetricSpec
-from metricflow_semantics.specs.instance_spec import InstanceSpec, LinkableInstanceSpec
-from metricflow_semantics.specs.spec_set import InstanceSpecSet
+from metricflow_semantics.specs.instance_spec import InstanceSpecVisitor, LinkableInstanceSpec
 from metricflow_semantics.specs.time_dimension_spec import TimeDimensionSpec
 
 if typing.TYPE_CHECKING:
     from metricflow_semantics.model.semantics.metric_lookup import MetricLookup
     from metricflow_semantics.model.semantics.semantic_model_lookup import SemanticModelLookup
+    from metricflow_semantics.specs.measure_spec import MeasureSpec
+    from metricflow_semantics.specs.metadata_spec import MetadataSpec
+    from metricflow_semantics.specs.metric_spec import MetricSpec
 
 
 @dataclass(frozen=True)
@@ -90,8 +93,8 @@ def merge(self, other: LinkableSpecSet) -> LinkableSpecSet:
             group_by_metric_specs=self.group_by_metric_specs + other.group_by_metric_specs,
         )
 
-    @override
     @classmethod
+    @override
     def empty_instance(cls) -> LinkableSpecSet:
         return LinkableSpecSet()
 
@@ -136,14 +139,57 @@ def __len__(self) -> int:  # noqa: D105
         return len(self.dimension_specs) + len(self.time_dimension_specs) + len(self.entity_specs)
 
     @staticmethod
-    def create_from_spec_set(spec_set: InstanceSpecSet) -> LinkableSpecSet:  # noqa: D102
-        return LinkableSpecSet(
-            dimension_specs=spec_set.dimension_specs,
-            time_dimension_specs=spec_set.time_dimension_specs,
-            entity_specs=spec_set.entity_specs,
-            group_by_metric_specs=spec_set.group_by_metric_specs,
-        )
+    def create_from_specs(specs: Sequence[LinkableInstanceSpec]) -> LinkableSpecSet:  # noqa: D102
+        return _group_specs_by_type(specs)
 
-    @staticmethod
-    def create_from_specs(specs: Sequence[InstanceSpec]) -> LinkableSpecSet:  # noqa: D102
-        return LinkableSpecSet.create_from_spec_set(InstanceSpecSet.create_from_specs(specs))
+
+@dataclass
+class _GroupSpecByTypeVisitor(InstanceSpecVisitor[None]):
+    """Groups a spec by type into an `InstanceSpecSet`."""
+
+    dimension_specs: List[DimensionSpec] = dataclasses.field(default_factory=list)
+    entity_specs: List[EntitySpec] = dataclasses.field(default_factory=list)
+    time_dimension_specs: List[TimeDimensionSpec] = dataclasses.field(default_factory=list)
+    group_by_metric_specs: List[GroupByMetricSpec] = dataclasses.field(default_factory=list)
+
+    @override
+    def visit_measure_spec(self, measure_spec: MeasureSpec) -> None:
+        pass
+
+    @override
+    def visit_dimension_spec(self, dimension_spec: DimensionSpec) -> None:
+        self.dimension_specs.append(dimension_spec)
+
+    @override
+    def visit_time_dimension_spec(self, time_dimension_spec: TimeDimensionSpec) -> None:
+        self.time_dimension_specs.append(time_dimension_spec)
+
+    @override
+    def visit_entity_spec(self, entity_spec: EntitySpec) -> None:
+        self.entity_specs.append(entity_spec)
+
+    @override
+    def visit_group_by_metric_spec(self, group_by_metric_spec: GroupByMetricSpec) -> None:
+        self.group_by_metric_specs.append(group_by_metric_spec)
+
+    @override
+    def visit_metric_spec(self, metric_spec: MetricSpec) -> None:
+        pass
+
+    @override
+    def visit_metadata_spec(self, metadata_spec: MetadataSpec) -> None:
+        pass
+
+
+def _group_specs_by_type(specs: Sequence[LinkableInstanceSpec]) -> LinkableSpecSet:
+    """Groups a sequence of specs by type."""
+    grouper = _GroupSpecByTypeVisitor()
+    for spec in specs:
+        spec.accept(grouper)
+
+    return LinkableSpecSet(
+        dimension_specs=tuple(grouper.dimension_specs),
+        entity_specs=tuple(grouper.entity_specs),
+        time_dimension_specs=tuple(grouper.time_dimension_specs),
+        group_by_metric_specs=tuple(grouper.group_by_metric_specs),
+    )

metricflow-semantics/tests_metricflow_semantics/query/group_by_item/test_available_group_by_items.py

@@ -9,7 +9,6 @@
 from metricflow_semantics.query.group_by_item.group_by_item_resolver import GroupByItemResolver
 from metricflow_semantics.query.group_by_item.resolution_dag.dag import GroupByItemResolutionDag
 from metricflow_semantics.specs.linkable_spec_set import LinkableSpecSet
-from metricflow_semantics.specs.spec_set import group_specs_by_type
 from metricflow_semantics.test_helpers.config_helpers import MetricFlowTestConfiguration
 from metricflow_semantics.test_helpers.snapshot_helpers import assert_linkable_spec_set_snapshot_equal
 
@@ -37,5 +36,5 @@ def test_available_group_by_items(  # noqa: D103
         request=request,
         mf_test_configuration=mf_test_configuration,
         set_id="set0",
-        spec_set=LinkableSpecSet.create_from_spec_set(group_specs_by_type(result.specs)),
+        spec_set=LinkableSpecSet.create_from_specs(result.specs),
     )