generalize BaseConfig.update_from + call adapter factory methods in core

.changes/unreleased/Under the Hood-20240104-135849.yaml

@@ -0,0 +1,6 @@
+kind: Under the Hood
+body: Remove usage of dbt.adapters.factory in dbt/common
+time: 2024-01-04T13:58:49.221966-05:00
+custom:
+  Author: michelleark
+  Issue: "9334"

core/dbt/common/contracts/config/base.py

@@ -1,7 +1,10 @@
+# necessary for annotating constructors
+from __future__ import annotations
+
 from dataclasses import dataclass, Field
 
 from itertools import chain
-from typing import Callable, Dict, Any, List, TypeVar
+from typing import Callable, Dict, Any, List, TypeVar, Type
 
 from dbt.common.contracts.config.metadata import Metadata
 from dbt.common.exceptions import CompilationError, DbtInternalError
@@ -140,21 +143,18 @@ def _merge_dicts(cls, src: Dict[str, Any], data: Dict[str, Any]) -> Dict[str, An
             )
         return result
 
-    def update_from(self: T, data: Dict[str, Any], adapter_type: str, validate: bool = True) -> T:
+    def update_from(
+        self: T, data: Dict[str, Any], config_cls: Type[BaseConfig], validate: bool = True
+    ) -> T:
         """Given a dict of keys, update the current config from them, validate
         it, and return a new config with the updated values
         """
-        # sadly, this is a circular import
-        from dbt.adapters.factory import get_config_class_by_name
-
         dct = self.to_dict(omit_none=False)
 
-        adapter_config_cls = get_config_class_by_name(adapter_type)
-
         self_merged = self._merge_dicts(dct, data)
         dct.update(self_merged)
 
-        adapter_merged = adapter_config_cls._merge_dicts(dct, data)
+        adapter_merged = config_cls._merge_dicts(dct, data)
         dct.update(adapter_merged)
 
         # any remaining fields must be "clobber"

core/dbt/context/context_config.py

@@ -3,6 +3,7 @@
 from dataclasses import dataclass
 from typing import List, Iterator, Dict, Any, TypeVar, Generic, Optional
 
+from dbt.adapters.factory import get_config_class_by_name
 from dbt.config import RuntimeConfig, Project, IsFQNResource
 from dbt.contracts.graph.model_config import get_config_for
 from dbt.common.contracts.config.base import BaseConfig, _listify
@@ -199,9 +200,11 @@ def initial_result(self, resource_type: NodeType, base: bool) -> C:
     def _update_from_config(self, result: C, partial: Dict[str, Any], validate: bool = False) -> C:
         translated = self._active_project.credentials.translate_aliases(partial)
         translated = self.translate_hook_names(translated)
-        updated = result.update_from(
-            translated, self._active_project.credentials.type, validate=validate
-        )
+
+        adapter_type = self._active_project.credentials.type
+        adapter_config_cls = get_config_class_by_name(adapter_type)
+
+        updated = result.update_from(translated, adapter_config_cls, validate=validate)
         return updated
 
     def translate_hook_names(self, project_dict):