diff --git a/tests/common/log_helper/log_helper_test_main.py b/tests/common/log_helper/log_helper_test_main.py
index cd8cf6b..e69f7c4 100644
--- a/tests/common/log_helper/log_helper_test_main.py
+++ b/tests/common/log_helper/log_helper_test_main.py
@@ -49,6 +49,7 @@ def main(args):
     throw = 'throw' in args
     percent_autoformat = '%-autoformat' in args
     warn = 'warn' in args
+    exc_info = 'exc-info' in args
 
     log_helper_test_imported.logger.setLevel(logging.ERROR)
 
@@ -64,6 +65,12 @@ def main(args):
         warnings.warn(ACTUAL_WARNING)
         log_helper_test_imported.warn()
 
+    if exc_info:
+        try:
+            raise Exception('This is an exception')
+        except Exception:
+            logger.exception('Caught exception')  # has exc_info=True
+
     log_helper.end_logging()
 
 
diff --git a/tests/common/log_helper/test_log_helper.py b/tests/common/log_helper/test_log_helper.py
index aa26037..1226743 100644
--- a/tests/common/log_helper/test_log_helper.py
+++ b/tests/common/log_helper/test_log_helper.py
@@ -17,8 +17,7 @@ from os.path import dirname, join, relpath, abspath
 from tests.test_utils import PROJECT_ROOT
 
 # test file we use as "main" module
-TEST_FILE = relpath(join(dirname(abspath(__file__)), 'log_helper_test_main.py'),
-                    PROJECT_ROOT)
+TEST_FILE = join(dirname(abspath(__file__)), 'log_helper_test_main.py')
 
 # test file simulating a third party main module that only imports oletools
 TEST_FILE_3RD_PARTY = relpath(join(dirname(abspath(__file__)),
@@ -27,6 +26,8 @@ TEST_FILE_3RD_PARTY = relpath(join(dirname(abspath(__file__)),
 
 PYTHON_EXECUTABLE = sys.executable
 
+PERCENT_FORMAT_OUTPUT = 'The answer is 47.'
+
 
 class TestLogHelper(unittest.TestCase):
     def test_it_doesnt_log_when_not_enabled(self):
@@ -114,7 +115,7 @@ class TestLogHelper(unittest.TestCase):
     def test_percent_autoformat(self):
         """Test that auto-formatting of log strings with `%` works."""
         output = self._run_test(['enable', '%-autoformat', 'info'])
-        self.assertIn('The answer is 47.', output)
+        self.assertIn(PERCENT_FORMAT_OUTPUT, output)
 
     def test_json_correct_on_exceptions(self):
         """
@@ -208,6 +209,21 @@ class TestLogHelper(unittest.TestCase):
         ])
         self.assertEqual(output.strip(), expect)
 
+    def test_json_percent_formatting(self):
+        """Test that json-output has formatting args included in output."""
+        output = self._run_test(['enable', 'as-json', '%-autoformat', 'info'])
+        json.loads(output)    # check that this does not raise, so json is valid
+        self.assertIn(PERCENT_FORMAT_OUTPUT, output)
+
+    def test_json_exception_formatting(self):
+        """Test that json-output has formatted exception info in output"""
+        output = self._run_test(['enable', 'as-json', 'exc-info', 'info'])
+        json.loads(output)    # check that this does not raise, so json is valid
+        self.assertIn('Caught exception', output)      # actual log message
+        self.assertIn('This is an exception', output)    # message of caught exception
+        self.assertIn('Traceback (most recent call last)', output)    # start of trace
+        self.assertIn(TEST_FILE, output)        # part of trace
+
     def _assert_json_messages(self, output, messages):
         try:
             json_data = json.loads(output)