Every state's part-year and nonresident returns allow the taxpayer to allocate income, it just varies in how they do it. Mass may show you all of your income as if you were a Mass resident and ask you to subtract out the non-MA income. I know TT/Calif shows you each income item as if you were a Calif resident all year and requires you to enter the amount that is Calif-source (Schedule CA(540NR), Part II, column E. use Forms Mode to see it). No TT/State can do that for you automatically - especially if it's not W-2 income - because it can't tell where your consulting income comes from. You have to make the allocation and that is offered to you by both TT nonresident state programs. It's typically near the end of the state's Step-by-Step. TT/California's is titled, Nonresident Adjustments.
