diff --git a/tests/data/test_llvm_coverage_report.py b/tests/data/test_llvm_coverage_report.py
index 0e4ec580e..9c88573b3 100644
--- a/tests/data/test_llvm_coverage_report.py
+++ b/tests/data/test_llvm_coverage_report.py
@@ -4,6 +4,7 @@
 from collections import defaultdict
 from pathlib import Path
 from tempfile import TemporaryDirectory
+from unittest.mock import patch
 
 from plumbum import colors, local
 
@@ -407,8 +408,9 @@ def test_cov_show(self):
                                                ).replace("\x1b[41m\x1b[0m", "")
             self.assertEqual(cov_show_slow_color_txt, output)
 
-    @unittest.skipIf(
-        not module_exists("vara_feature"), "vara_feature module not installed"
+    @patch(
+        "varats.data.reports.llvm_coverage_report.CoverageReport._extract_feature_option_mapping",
+        lambda self, xml: None
     )
     @run_in_test_environment(
         UnitTestFixtures.PAPER_CONFIGS, UnitTestFixtures.RESULT_FILES
diff --git a/tests/plots/test_llvm_coverage_plot.py b/tests/plots/test_llvm_coverage_plot.py
index 1a2a43d64..3ebf92762 100644
--- a/tests/plots/test_llvm_coverage_plot.py
+++ b/tests/plots/test_llvm_coverage_plot.py
@@ -1,6 +1,6 @@
 import typing as tp
 import unittest
-from unittest.mock import create_autospec
+from unittest.mock import create_autospec, patch
 
 from tests.helper_utils import run_in_test_environment, UnitTestFixtures
 from varats.data.reports.llvm_coverage_report import (
@@ -290,9 +290,6 @@ def confusion_matrix(
         self.assertEqual(confusion_matrix(region, 1.0).TN, 1)
         self.assertEqual(confusion_matrix(region, 0.0).TN, 1)
 
-    @unittest.skipIf(
-        not module_exists("vara_feature"), "vara_feature module not installed"
-    )
     @run_in_test_environment(
         UnitTestFixtures.PAPER_CONFIGS, UnitTestFixtures.RESULT_FILES
     )
@@ -303,9 +300,13 @@ def test_feature_report_interactions(self):
             "FeaturePerfCSCollection", commit_hash.to_short_commit_hash()
         ) as base_dir:
 
-            reports = setup_reports(
-                "test_coverage_SimpleFeatureInteraction", base_dir
-            )
+            with patch(
+                "varats.data.reports.llvm_coverage_report.CoverageReport._extract_feature_option_mapping",
+                lambda self, xml: None
+            ):
+                reports = setup_reports(
+                    "test_coverage_SimpleFeatureInteraction", base_dir
+                )
             report = reports.feature_report()
 
             code_region = report.tree["src/SimpleFeatureInteraction/SFImain.cpp"
@@ -340,9 +341,6 @@ def test_feature_report_interactions(self):
                         pass
                     self.assertIn(region.coverage_features(), ["", "+True"])
 
-    @unittest.skipIf(
-        not module_exists("vara_feature"), "vara_feature module not installed"
-    )
     @run_in_test_environment(
         UnitTestFixtures.PAPER_CONFIGS, UnitTestFixtures.RESULT_FILES
     )
@@ -522,9 +520,6 @@ def test_line_feature_plot(self):
                 )
             )
 
-    @unittest.skipIf(
-        not module_exists("vara_feature"), "vara_feature module not installed"
-    )
     @run_in_test_environment(
         UnitTestFixtures.PAPER_CONFIGS, UnitTestFixtures.RESULT_FILES
     )
@@ -534,10 +529,20 @@ def test_confusion_matrices(self):
         with RepositoryAtCommit(
             "FeaturePerfCSCollection", commit_hash.to_short_commit_hash()
         ) as base_dir:
-
-            reports = setup_reports(
-                "test_coverage_SimpleFeatureInteraction", base_dir
-            )
+            with patch(
+                "varats.data.reports.llvm_coverage_report.CoverageReport._extract_feature_option_mapping",
+                lambda self, xml: self.__setattr__(
+                    "featue_option_mapping", {
+                        "root": "",
+                        "Compression": "--compress",
+                        "Encryption": "--enc",
+                        "Slow": "--slow"
+                    }
+                )
+            ):
+                reports = setup_reports(
+                    "test_coverage_SimpleFeatureInteraction", base_dir
+                )
             feature_option_mapping = reports.feature_option_mapping()
             result_1 = reports.confusion_matrices(
                 feature_option_mapping, threshold=1.0
diff --git a/varats/varats/data/reports/llvm_coverage_report.py b/varats/varats/data/reports/llvm_coverage_report.py
index 45f97d154..75801687c 100644
--- a/varats/varats/data/reports/llvm_coverage_report.py
+++ b/varats/varats/data/reports/llvm_coverage_report.py
@@ -504,7 +504,9 @@ def __contains__(self, element: CodeRegion) -> bool:
 class FilenameRegionMapping(tp.Dict[str, CodeRegion]):
     """Mapping from function names to CodeRegion objects."""
 
-    def __init__(self, *args, base_dir: tp.Optional[Path] = None, **kwargs):
+    def __init__(
+        self, *args, base_dir: tp.Optional[Path] = None, **kwargs
+    ) -> None:
         self.base_dir = base_dir
         super().__init__(*args, **kwargs)