convert 038_caching_tests (#6612)

* convert 038_caching_tests

* Adapt for dbt-snowflake

* PR feedback

* Reformat

tests/adapter/dbt/tests/adapter/caching/test_caching.py

@@ -0,0 +1,103 @@
+import pytest
+
+from dbt.tests.util import run_dbt
+
+model_sql = """
+{{
+    config(
+        materialized='table'
+    )
+}}
+select 1 as id
+"""
+
+another_schema_model_sql = """
+{{
+    config(
+        materialized='table',
+        schema='another_schema'
+    )
+}}
+select 1 as id
+"""
+
+
+class BaseCachingTest:
+    @pytest.fixture(scope="class")
+    def project_config_update(self):
+        return {
+            "config-version": 2,
+            "quoting": {
+                "identifier": False,
+                "schema": False,
+            },
+        }
+
+    def run_and_inspect_cache(self, project, run_args=None):
+        run_dbt(run_args)
+
+        # the cache was empty at the start of the run.
+        # the model materialization returned an unquoted relation and added to the cache.
+        adapter = project.adapter
+        assert len(adapter.cache.relations) == 1
+        relation = list(adapter.cache.relations).pop()
+        assert relation.schema == project.test_schema
+        assert relation.schema == project.test_schema.lower()
+
+        # on the second run, dbt will find a relation in the database during cache population.
+        # this relation will be quoted, because list_relations_without_caching (by default) uses
+        # quote_policy = {"database": True, "schema": True, "identifier": True}
+        # when adding relations to the cache.
+        run_dbt(run_args)
+        adapter = project.adapter
+        assert len(adapter.cache.relations) == 1
+        second_relation = list(adapter.cache.relations).pop()
+
+        # perform a case-insensitive + quote-insensitive comparison
+        for key in ["database", "schema", "identifier"]:
+            assert getattr(relation, key).lower() == getattr(second_relation, key).lower()
+
+    def test_cache(self, project):
+        self.run_and_inspect_cache(project, run_args=["run"])
+
+
+class BaseCachingLowercaseModel(BaseCachingTest):
+    @pytest.fixture(scope="class")
+    def models(self):
+        return {
+            "model.sql": model_sql,
+        }
+
+
+class BaseCachingUppercaseModel(BaseCachingTest):
+    @pytest.fixture(scope="class")
+    def models(self):
+        return {
+            "MODEL.sql": model_sql,
+        }
+
+
+class BaseCachingSelectedSchemaOnly(BaseCachingTest):
+    @pytest.fixture(scope="class")
+    def models(self):
+        return {
+            "model.sql": model_sql,
+            "another_schema_model.sql": another_schema_model_sql,
+        }
+
+    def test_cache(self, project):
+        # this should only cache the schema containing the selected model
+        run_args = ["--cache-selected-only", "run", "--select", "model"]
+        self.run_and_inspect_cache(project, run_args)
+
+
+class TestCachingLowerCaseModel(BaseCachingLowercaseModel):
+    pass
+
+
+class TestCachingUppercaseModel(BaseCachingUppercaseModel):
+    pass
+
+
+class TestCachingSelectedSchemaOnly(BaseCachingSelectedSchemaOnly):
+    pass