chore: convert log into error

modules/neo4j/config.go

@@ -106,8 +106,7 @@ func addSetting(req *testcontainers.GenericContainerRequest, key string, newVal
 	if oldVal, found := req.Env[normalizedKey]; found {
 		// make sure AUTH is not overwritten by a setting
 		if key == "AUTH" {
-			req.Logger.Printf("setting %q is not permitted, WithAdminPassword has already been set\n", normalizedKey)
-			return nil
+			return fmt.Errorf("setting %q is not permitted, WithAdminPassword has already been set", normalizedKey)
 		}
 
 		req.Logger.Printf("setting %q with value %q is now overwritten with value %q\n", []any{key, oldVal, newVal}...)

modules/neo4j/neo4j_test.go

@@ -115,24 +115,16 @@ func TestNeo4jWithWrongSettings(outer *testing.T) {
 		})
 	})
 
-	outer.Run("ignores auth setting outside WithAdminPassword", func(t *testing.T) {
+	outer.Run("auth setting outside WithAdminPassword raises error", func(t *testing.T) {
 		container, err := neo4j.RunContainer(ctx,
 			neo4j.WithAdminPassword(testPassword),
-			neo4j.WithNeo4jSetting("AUTH", "neo4j/thisisgonnabeignored"),
+			neo4j.WithNeo4jSetting("AUTH", "neo4j/thisisgonnafail"),
 		)
-		if err != nil {
-			t.Fatalf("expected env to successfully run but did not: %s", err)
+		if err == nil {
+			t.Fatalf("expected env to fail due to conflicting auth settings but did not")
 		}
-		t.Cleanup(func() {
-			if err := container.Terminate(ctx); err != nil {
-				outer.Fatalf("failed to terminate container: %s", err)
-			}
-		})
-
-		env := getContainerEnv(t, ctx, container)
-
-		if !strings.Contains(env, "NEO4J_AUTH=neo4j/"+testPassword) {
-			t.Fatalf("expected WithAdminPassword to have higher precedence than auth set with WithNeo4jSetting")
+		if container != nil {
+			t.Fatalf("container must not be created with conflicting auth settings")
 		}
 	})