diff --git a/dexpreopt/dexpreopt_test.go b/dexpreopt/dexpreopt_test.go
index 12df36b..cd7551c 100644
--- a/dexpreopt/dexpreopt_test.go
+++ b/dexpreopt/dexpreopt_test.go
@@ -166,3 +166,20 @@
 		t.Errorf("\nwant installs:\n   %v\ngot:\n   %v", wantInstalls, rule.Installs())
 	}
 }
+
+func TestDexPreoptConfigToJson(t *testing.T) {
+	config := android.TestConfig("out", nil, "", nil)
+	ctx := android.BuilderContextForTesting(config)
+	module := testSystemModuleConfig(ctx, "test")
+	data, err := moduleConfigToJSON(module)
+	if err != nil {
+		t.Errorf("Failed to convert module config data to JSON, %v", err)
+	}
+	parsed, err := ParseModuleConfig(ctx, data)
+	if err != nil {
+		t.Errorf("Failed to parse JSON, %v", err)
+	}
+	before := fmt.Sprintf("%v", module)
+	after := fmt.Sprintf("%v", parsed)
+	android.AssertStringEquals(t, "The result must be the same as the original after marshalling and unmarshalling it.", before, after)
+}