diff --git a/CHANGELOG.rst b/CHANGELOG.rst
index aa372dc9..e39a66b4 100644
--- a/CHANGELOG.rst
+++ b/CHANGELOG.rst
@@ -3,6 +3,7 @@ v6.4.1
 
 
 * fix regression #669: restore get_version signature
+* fix #668: harden the selftest for distribution extras
 
 6.4.0
 ======
diff --git a/testing/test_integration.py b/testing/test_integration.py
index c0a22979..23d8966a 100644
--- a/testing/test_integration.py
+++ b/testing/test_integration.py
@@ -142,11 +142,11 @@ def testwarn_on_broken_setuptools():
 
 
 @pytest.mark.issue(611)
-def test_provides_toml_exta():
+def test_distribution_procides_extras():
     try:
         from importlib.metadata import distribution
     except ImportError:
         from importlib_metadata import distribution
 
     dist = distribution("setuptools_scm")
-    assert "toml" in dist.metadata["Provides-Extra"]
+    assert sorted(dist.metadata.get_all("Provides-Extra")) == ["test", "toml"]