diff --git a/timesketch/lib/analyzers/feature_test.py b/timesketch/lib/analyzers/feature_test.py
index bc9a799fd5..4b0e551bfd 100644
--- a/timesketch/lib/analyzers/feature_test.py
+++ b/timesketch/lib/analyzers/feature_test.py
@@ -14,13 +14,16 @@
 """Unit tests for feature extraction."""
 
 import os
+import re
 import textwrap
 from typing import List, Dict
 
 import yaml
 import mock
 
+from timesketch.lib import emojis
 from timesketch.lib.analyzers.feature import FeatureSketchPlugin
+from timesketch.lib.analyzers.feature_plugins import regex_features
 from timesketch.lib.analyzers.sequence_sessionizer_test import _create_eventObj
 from timesketch.lib.testlib import BaseTest
 from timesketch.lib.testlib import MockDataStore
@@ -151,3 +154,158 @@ def _create_mock_winevt_events(self) -> List[Dict]:
         events.append(security_4624_v2_event)
 
         return events
+
+    # Copied from feature_extraction_test
+
+    def _config_validation(self, config):
+        """Validate that all items of a config are valid."""
+        query = config.get("query_string", config.get("query_dsl"))
+        self.assertIsNotNone(query)
+        self.assertIsInstance(query, str)
+
+        attribute = config.get("attribute")
+        self.assertIsNotNone(attribute)
+
+        store_as = config.get("store_as")
+        self.assertIsNotNone(store_as)
+
+        expression = config.get("re")
+        self.assertIsNotNone(expression)
+        try:
+            _ = re.compile(expression)
+        except re.error as exception:
+            self.assertIsNone(exception)
+
+        emojis_to_add = config.get("emojis")
+        if emojis_to_add:
+            self.assertIsInstance(emojis_to_add, (list, tuple))
+            for emoji_name in emojis_to_add:
+                emoji_code = emojis.get_emoji(emoji_name)
+                self.assertNotEqual(emoji_code, "")
+
+        tags = config.get("tags")
+        if tags:
+            self.assertIsInstance(tags, (list, tuple))
+
+        create_view = config.get("create_view")
+        if create_view:
+            self.assertIsInstance(create_view, bool)
+
+        aggregate = config.get("aggregate")
+        if aggregate:
+            self.assertIsInstance(aggregate, bool)
+
+    # TODO: Add tests for the feature extraction.
+    def test_config(self):
+        """Tests that the config file is valid."""
+        config_file = os.path.join("data", "features.yaml")
+        self.assertTrue(os.path.isfile(config_file))
+
+        with open(config_file) as fh:
+            config = yaml.safe_load(fh)
+
+        self.assertIsInstance(config, dict)
+
+        for key, value in iter(config.items()):
+            self.assertIsInstance(key, str)
+            self.assertIsInstance(value, dict)
+            self._config_validation(value)
+
+    # Mock the OpenSearch datastore.
+    @mock.patch("timesketch.lib.analyzers.interface.OpenSearchDataStore", MockDataStore)
+    def test_get_attribute_value(self):
+        """Test function _get_attribute_value()."""
+        analyzer = FeatureSketchPlugin(
+            index_name="test_index", sketch_id=1, timeline_id=1
+        )
+        plugin = regex_features.RegexFeatureExtractionPlugin(analyzer)
+
+        current_val = ["hello"]
+        extracted_value = ["hello"]
+        # pylint: disable=protected-access
+        new_val = plugin._get_attribute_value(
+            current_val=current_val,
+            extracted_value=extracted_value,
+            keep_multi=True,
+            merge_values=True,
+            type_list=True,
+        )
+        new_val.sort()
+
+        self.assertEqual(new_val, ["hello"])
+
+        current_val = ["hello"]
+        extracted_value = ["hello2", "hello3"]
+        # pylint: disable=protected-access
+        new_val = plugin._get_attribute_value(
+            current_val, extracted_value, True, True, True
+        )
+        new_val.sort()
+
+        self.assertEqual(new_val, ["hello", "hello2", "hello3"])
+
+        current_val = ["hello"]
+        extracted_value = ["hello2", "hello3"]
+        # pylint: disable=protected-access
+        new_val = plugin._get_attribute_value(
+            current_val, extracted_value, False, True, True
+        )
+        new_val.sort()
+
+        self.assertEqual(new_val, ["hello", "hello2"])
+
+        current_val = ["hello"]
+        extracted_value = ["hello2", "hello3"]
+        # pylint: disable=protected-access
+        new_val = plugin._get_attribute_value(
+            current_val, extracted_value, False, False, True
+        )
+        new_val.sort()
+
+        self.assertEqual(new_val, ["hello2"])
+
+        current_val = ["hello"]
+        extracted_value = ["hello2", "hello3"]
+        # pylint: disable=protected-access
+        new_val = plugin._get_attribute_value(
+            current_val, extracted_value, True, False, True
+        )
+        new_val.sort()
+
+        self.assertEqual(new_val, ["hello2", "hello3"])
+
+        current_val = "hello"
+        extracted_value = ["hello2", "hello3"]
+        # pylint: disable=protected-access
+        new_val = plugin._get_attribute_value(
+            current_val, extracted_value, True, True, False
+        )
+
+        self.assertEqual(new_val, "hello,hello2,hello3")
+
+        current_val = "hello"
+        extracted_value = ["hello2", "hello3"]
+        # pylint: disable=protected-access
+        new_val = plugin._get_attribute_value(
+            current_val, extracted_value, False, True, False
+        )
+
+        self.assertEqual(new_val, "hello,hello2")
+
+        current_val = "hello"
+        extracted_value = ["hello2", "hello3"]
+        # pylint: disable=protected-access
+        new_val = plugin._get_attribute_value(
+            current_val, extracted_value, True, False, False
+        )
+
+        self.assertEqual(new_val, "hello2,hello3")
+
+        current_val = "hello"
+        extracted_value = ["hello2", "hello3"]
+        # pylint: disable=protected-access
+        new_val = plugin._get_attribute_value(
+            current_val, extracted_value, False, False, False
+        )
+
+        self.assertEqual(new_val, "hello2")