Typing with inserts

Hi there. What a lovely library. I'm encountering a typing issue with dynamic inserts: Type of 'await' operand must either be a valid promise or must not contain a callable 'then' member.

const users = [{
  name: 'Murray',
  age: 68,
  garbage: 'ignore'
},
{
  name: 'Walter',
  age: 80
}];

await sql`insert into users ${sql(users, 'name', 'age')}`; // fine
await sql`insert into users ${sql(users, 'name', 'age')} returning id`; // fine
await sql<{ id: number }[]>`insert into users ${sql(users, 'name', 'age')} returning id`; // Type of 'await' operand must either be a valid promise or must not contain a callable 'then' member.

something I'm doing wrong?

Start with the TypeScript reproduction in the issue and compare the inferred type of the tagged query with and without the explicit result type. The issue is done when the explicit generic compiles without the await error while the existing insert examples continue to type-check.