better naming

python_modules/dagster/dagster/_core/execution/context/compute.py

@@ -1462,7 +1462,13 @@ def job_def(self) -> JobDefinition:
     def latest_materialization_event(
         self, key: CoercibleToAssetKey
     ) -> Optional[AssetMaterialization]:
-        return self._step_execution_context.latest_materialization_event.get(
+        """Get the most recent AssetMaterialization event for the key. Information like metadata and tags
+        can be found on the AssetMaterialization. If the key is not an upstream asset of the currently
+        materializing asset, None will be returned.
+
+        Returns: Optional[AssetMaterialization]
+        """
+        return self._step_execution_context.upstream_asset_materialization_events.get(
             AssetKey.from_coercible(key)
         )
 

python_modules/dagster/dagster/_core/execution/context/system.py

@@ -571,7 +571,9 @@ def __init__(
         self._output_metadata: Dict[str, Any] = {}
         self._seen_outputs: Dict[str, Union[str, Set[str]]] = {}
 
-        self.latest_materialization_event: Dict[AssetKey, Optional[AssetMaterialization]] = {}
+        self._upstream_asset_materialization_events: Dict[
+            AssetKey, Optional[AssetMaterialization]
+        ] = {}
 
         self._input_asset_version_info: Dict[AssetKey, Optional["InputAssetVersionInfo"]] = {}
         self._is_external_input_asset_version_info_loaded = False
@@ -951,6 +953,12 @@ def get_data_version(self, asset_key: AssetKey) -> "DataVersion":
     def input_asset_records(self) -> Optional[Mapping[AssetKey, Optional["InputAssetVersionInfo"]]]:
         return self._input_asset_version_info
 
+    @property
+    def upstream_asset_materialization_events(
+        self,
+    ) -> Dict[AssetKey, Optional[AssetMaterialization]]:
+        return self._upstream_asset_materialization_events
+
     @property
     def is_external_input_asset_version_info_loaded(self) -> bool:
         return self._is_external_input_asset_version_info_loaded
@@ -991,9 +999,9 @@ def _fetch_input_asset_materialization_and_version_info(self, key: AssetKey) ->
         event = self._get_input_asset_event(key)
         if event is None:
             self._input_asset_version_info[key] = None
-            self.latest_materialization_event[key] = None
+            self._upstream_asset_materialization_events[key] = None
         else:
-            self.latest_materialization_event[key] = (
+            self._upstream_asset_materialization_events[key] = (
                 event.asset_materialization if event.asset_materialization else None
             )
             storage_id = event.storage_id