Adap 821/unit test infer wrong datatype (#852)

* Add test to confirm upstream handling

* Add changelog.

* Add another test.

* standardize names to reflect python objects.

* revert dev requirements.

---------

Co-authored-by: Mila Page <[email protected]>

.changes/unreleased/Fixes-20240625-170324.yaml

@@ -0,0 +1,7 @@
+kind: Fixes
+body: 'Handle unit test fixtures where typing goes wrong from first value in column
+  being Null. '
+time: 2024-06-25T17:03:24.73937-07:00
+custom:
+  Author: versusfacit
+  Issue: "821"

tests/functional/adapter/unit_testing/fixtures.py

@@ -0,0 +1,73 @@
+model_none_value_base = """
+{{ config(materialized="table") }}
+
+select 1 as id, 'a' as col1
+"""
+
+model_none_value_model = """
+{{config(materialized="table")}}
+
+select * from {{ ref('none_value_base') }}
+"""
+
+
+test_none_column_value_doesnt_throw_error_csv = """
+unit_tests:
+  - name: test_simple
+
+    model: none_value_model
+    given:
+      - input: ref('none_value_base')
+        format: csv
+        rows: |
+          id,col1
+          ,d
+          ,e
+          6,f
+
+    expect:
+        format: csv
+        rows: |
+          id,col1
+          ,d
+          ,e
+          6,f
+"""
+
+test_none_column_value_doesnt_throw_error_dct = """
+unit_tests:
+  - name: test_simple
+
+    model: none_value_model
+    given:
+      - input: ref('none_value_base')
+        rows:
+          - { "id":  , "col1": "d"}
+          - { "id":  , "col1": "e"}
+          - { "id": 6, "col1": "f"}
+
+    expect:
+      rows:
+        - {id:  , "col1": "d"}
+        - {id:  , "col1": "e"}
+        - {id: 6, "col1": "f"}
+"""
+
+test_none_column_value_will_throw_error = """
+unit_tests:
+  - name: test_simple
+
+    model: none_value_model
+    given:
+      - input: ref('none_value_base')
+        rows:
+          - { "id":  , "col1": "d"}
+          - { "id":  , "col1": "e"}
+          - { "id": 6, "col1": }
+
+    expect:
+      rows:
+        - {id:  , "col1": "d"}
+        - {id:  , "col1": "e"}
+        - {id: 6, "col1": }
+"""

tests/functional/adapter/unit_testing/test_unit_testing.py

@@ -1,7 +1,19 @@
 import pytest
+
+from dbt.exceptions import ParsingError
+from dbt.tests.fixtures.project import write_project_files
+from dbt.tests.util import run_dbt
+
 from dbt.tests.adapter.unit_testing.test_types import BaseUnitTestingTypes
 from dbt.tests.adapter.unit_testing.test_case_insensitivity import BaseUnitTestCaseInsensivity
 from dbt.tests.adapter.unit_testing.test_invalid_input import BaseUnitTestInvalidInput
+from tests.functional.adapter.unit_testing.fixtures import (
+    model_none_value_base,
+    model_none_value_model,
+    test_none_column_value_doesnt_throw_error_csv,
+    test_none_column_value_doesnt_throw_error_dct,
+    test_none_column_value_will_throw_error,
+)
 
 
 class TestRedshiftUnitTestingTypes(BaseUnitTestingTypes):
@@ -34,6 +46,47 @@ def data_types(self):
         ]
 
 
+class RedshiftUnitTestingNone:
+    def test_nones_handled_dict(self, project):
+        run_dbt(["build"])
+
+
+class TestRedshiftUnitTestCsvNone(RedshiftUnitTestingNone):
+    @pytest.fixture(scope="class")
+    def models(self):
+        return {
+            "none_value_base.sql": model_none_value_base,
+            "none_value_model.sql": model_none_value_model,
+            "__properties.yml": test_none_column_value_doesnt_throw_error_csv,
+        }
+
+
+class TestRedshiftUnitTestDictNone(RedshiftUnitTestingNone):
+    @pytest.fixture(scope="class")
+    def models(self):
+        return {
+            "none_value_base.sql": model_none_value_base,
+            "none_value_model.sql": model_none_value_model,
+            "__properties.yml": test_none_column_value_doesnt_throw_error_dct,
+        }
+
+
+class TestRedshiftUnitTestingTooManyNonesFails:
+    @pytest.fixture(scope="class")
+    def models(self):
+        return {
+            "__properties.yml": test_none_column_value_will_throw_error,
+            "none_value_base.sql": model_none_value_base,
+            "none_value_model.sql": model_none_value_model,
+        }
+
+    def test_invalid_input(self, project):
+        with pytest.raises(ParsingError) as e:
+            run_dbt(["build"])
+
+        assert "Unit Test fixtures require at least one row free of None" in str(e)
+
+
 class TestRedshiftUnitTestCaseInsensitivity(BaseUnitTestCaseInsensivity):
     pass