diff --git a/tests/sources/test_sourcecode_page.py b/tests/sources/test_sourcecode_page.py
index 3e3d4c3..7ffce2d 100644
--- a/tests/sources/test_sourcecode_page.py
+++ b/tests/sources/test_sourcecode_page.py
@@ -7,6 +7,7 @@
     get_github_readme,
     search_in_readme,
     SourcecodePage,
+    replace_chars,
 )
 
 
@@ -55,6 +56,17 @@ def test_get_github_readme(
             )
 
 
+class TestReplaceChars(unittest.TestCase):
+    """Test the replace_chars function."""
+
+    def test_replace_chars(self):
+        """Test the replace_chars function."""
+        with self.subTest("Test with dash char"):
+            self.assertEqual("package-name123", replace_chars("package-name123"))
+        with self.subTest("Test with other chars"):
+            self.assertEqual("package-name-123", replace_chars("package_name.123"))
+
+
 class TestSearchInReadme(unittest.TestCase):
     """Test the search_in_readme function."""