hyperledger-solang_solang/tests/contract_testcases/substrate/inheritance/multiple_override_01.sol

        contract base is bar, bar2 {
            function foo(uint64 a) override(bar) internal returns (uint64) {
                return a + 102;
            }
        }

        contract bar {
            function foo(uint64 a) virtual internal returns (uint64) {
                return a + 102;
            }
        }

        contract bar2 {
            function foo(uint64 a) virtual internal returns (uint64) {
                return a + 103;
            }
        }
        
// ---- Expect: diagnostics ----
// error: 3:36-49: function 'foo' missing overrides 'bar2', specify 'override(bar2,bar)'