#150: Add beginning of tests for ICATQuery

- This commit also includes a skeleton for the remaining tests for this class

test/icat/test_query.py

@@ -0,0 +1,92 @@
+from icat.entity import Entity
+import pytest
+
+from datagateway_api.common.exceptions import PythonICATError
+from datagateway_api.common.icat.filters import PythonICATWhereFilter
+from datagateway_api.common.icat.query import ICATQuery
+
+
+def remove_meta_attributes(entity_dict):
+    meta_attributes = Entity.MetaAttr
+    for attr in meta_attributes:
+        entity_dict.pop(attr)
+
+
+class TestICATQuery:
+    def test_valid_query_creation(self, icat_client):
+        # Paramitise and add inputs for conditions, aggregate and includes
+        test_query = ICATQuery(icat_client, "User")
+
+        assert test_query.query.entity == icat_client.getEntityClass("User")
+
+    def test_invalid_query_creation(self, icat_client):
+        with pytest.raises(PythonICATError):
+            ICATQuery(icat_client, "User", conditions={"invalid": "invalid"})
+
+    # @pytest.mark.usefixtures("")
+    def test_valid_query_exeuction(
+        self, icat_client, add_single_investigation_test_data,
+    ):
+        test_query = ICATQuery(icat_client, "Investigation")
+        test_data_filter = PythonICATWhereFilter(
+            "title", "Test data for the Python ICAT Backend on DataGateway API", "eq",
+        )
+        test_data_filter.apply_filter(test_query.query)
+        query_data = test_query.execute_query(icat_client)
+
+        query_output_dicts = []
+        for entity in query_data:
+            entity_dict = entity.as_dict()
+            remove_meta_attributes(entity_dict)
+            query_output_dicts.append(entity_dict)
+
+        assert query_output_dicts == add_single_investigation_test_data
+
+    def test_invalid_query_execution(self, icat_client):
+        # Try to get ICATValidationError raised
+        pass
+
+    def test_valid_count_query_execution(self, icat_client):
+        pass
+
+    def test_valid_distinct_query_execution(self, icat_client):
+        pass
+
+    def test_json_format_execution_output(self, icat_client):
+        pass
+
+    def test_icat_execution_output(self, icat_client):
+        pass
+
+    # gap in function testing
+
+    def test_valid_entity_to_dict_conversion(self, icat_client):
+        # Want just a typical entity and an entity with an entity list in it
+        pass
+
+    def test_valid_distinct_attribute_mapping(self):
+        pass
+
+    # another gap
+
+    def test_include_fields_list_flatten(self, icat_client):
+        included_field_set = {
+            "investigationUsers.investigation.datasets",
+            "userGroups",
+            "instrumentScientists",
+            "studies",
+        }
+
+        test_query = ICATQuery(icat_client, "User")
+
+        flat_list = test_query.flatten_query_included_fields(included_field_set)
+        print(flat_list)
+
+        assert flat_list == [
+            "instrumentScientists",
+            "investigationUsers",
+            "investigation",
+            "datasets",
+            "studies",
+            "userGroups",
+        ]