Speed up equality checks for build_dbt_asset_selection asset selectio…

…ns (#25434)

Current implementation does a full equality check on the full manifest.
Scope it down to just the "metadata" part of the manifest, which is much
smaller and faster to compare.

## How I Tested These Changes
New tests
Speed scope importing code like this and see a marked improvement:
```
dbt_job_6 = define_asset_job(
    name="dbt_6",
    selection=build_dbt_asset_selection(dbt_assets=[dbt_project_assets]),
)


@sensor(job=dbt_job_6)
def my_sensor():
    pass
```

## Changelog
[dagster-dbt] Performance improvements when loading definitions using
`build_dbt_asset_selection`.

python_modules/dagster/dagster/_core/definitions/asset_selection.py

@@ -648,6 +648,15 @@ def to_serializable_asset_selection(self, asset_graph: BaseAssetGraph) -> "Asset
             )
         )
 
+    def __eq__(self, other):
+        if not isinstance(other, OperandListAssetSelection):
+            return False
+
+        num_operands = len(self.operands)
+        return len(other.operands) == num_operands and all(
+            self.operands[i] == other.operands[i] for i in range(num_operands)
+        )
+
     def needs_parentheses_when_operand(self) -> bool:
         return True
 

python_modules/libraries/dagster-dbt/dagster_dbt/dbt_manifest_asset_selection.py

@@ -45,6 +45,25 @@ class DbtManifestAssetSelection(AssetSelection, arbitrary_types_allowed=True):
     dagster_dbt_translator: DagsterDbtTranslator
     exclude: str
 
+    def __eq__(self, other):
+        if not isinstance(other, DbtManifestAssetSelection):
+            return False
+
+        self_metadata = self.manifest.get("metadata")
+        other_metadata = other.manifest.get("metadata")
+
+        if not self_metadata or not other_metadata:
+            return super().__eq__(other)
+
+        # Compare metadata only since it uniquely identifies the manifest and the
+        # full manifest dictionary can be large
+        return (
+            self_metadata == other_metadata
+            and self.select == other.select
+            and self.dagster_dbt_translator == other.dagster_dbt_translator
+            and self.exclude == other.exclude
+        )
+
     @classmethod
     def build(
         cls,

python_modules/libraries/dagster-dbt/dagster_dbt_tests/core/test_asset_selection.py

@@ -1,12 +1,16 @@
+import copy
 import os
 from pathlib import Path
-from typing import Any, Dict, Optional, Set
+from typing import Any, Dict, Optional, Set, cast
+from unittest import mock
 
 import pytest
 from dagster._core.definitions.asset_graph import AssetGraph
+from dagster._core.definitions.asset_selection import AndAssetSelection
 from dagster._core.definitions.events import AssetKey
 from dagster_dbt import build_dbt_asset_selection
 from dagster_dbt.asset_decorator import dbt_assets
+from dagster_dbt.dbt_manifest_asset_selection import DbtManifestAssetSelection
 
 
 @pytest.mark.parametrize(
@@ -240,3 +244,54 @@ def my_dbt_assets(): ...
         selected_asset_keys = asset_selection.resolve(all_assets=asset_graph)
 
         assert selected_asset_keys == expected_asset_keys
+
+
+def test_dbt_asset_selection_equality(
+    test_jaffle_shop_manifest_path: Path, test_jaffle_shop_manifest: Dict[str, Any]
+) -> None:
+    for manifest_param in [
+        test_jaffle_shop_manifest,
+        test_jaffle_shop_manifest_path,
+        os.fspath(test_jaffle_shop_manifest_path),
+    ]:
+
+        @dbt_assets(manifest=manifest_param)
+        def my_dbt_assets(): ...
+
+        asset_selection = build_dbt_asset_selection([my_dbt_assets], dbt_select="fqn:*")
+
+        assert asset_selection == asset_selection
+
+        assert asset_selection != build_dbt_asset_selection(
+            [my_dbt_assets], dbt_select="new_select"
+        )
+
+        dbt_manifest_asset_selection = cast(AndAssetSelection, asset_selection).operands[0]
+
+        assert isinstance(dbt_manifest_asset_selection, DbtManifestAssetSelection)
+
+        altered_manifest = copy.deepcopy(dbt_manifest_asset_selection.manifest)
+        altered_manifest["metadata"]["project_id"] = 12345
+
+        assert dbt_manifest_asset_selection != dbt_manifest_asset_selection.model_copy(
+            update={"manifest": altered_manifest}
+        )
+
+        assert dbt_manifest_asset_selection != dbt_manifest_asset_selection.model_copy(
+            update={"select": "other_select"}
+        )
+
+        assert dbt_manifest_asset_selection != dbt_manifest_asset_selection.model_copy(
+            update={"dagster_dbt_translator": mock.MagicMock()}
+        )
+
+        assert dbt_manifest_asset_selection != dbt_manifest_asset_selection.model_copy(
+            update={"exclude": "other_exclude"}
+        )
+
+        # changing non-metadata fields does not affect equality
+        altered_nodes_manifest = dict(copy.deepcopy(dbt_manifest_asset_selection.manifest))
+        altered_nodes_manifest["nodes"] = []
+        assert dbt_manifest_asset_selection == dbt_manifest_asset_selection.model_copy(
+            update={"manifest": altered_nodes_manifest}
+        )