Tuple + Record Intersection Assignment Compatibility Inconsistency

TypeScript Version: 4.1.0-dev.20200824

Search Terms: tuple, object, intersection, type, assignment, coercion

Code

Here is the type that I'd like to use in an assignment:

type X = {example: "Field"} & number[];

The following produces TS error 2322.

const x: X = {
  ...[1, 2],
  example: "Field",
} as const;

If we update this example like so, the type error disappears:

- const x: X = {
+ const x = {
    ...[1, 2],
    example: "Field",
  } as const;

+ const y: X = x;

Expected behavior:

I would have expected the first assignment to not produce a type error. I'm wondering if this inconsistency (if that's the correct word for it) is an edge case, or by design? Apologies if this issue is unhelpful! Thank you!

Actual behavior:

Playground Link: https://www.typescriptlang.org/play?#code/HYQwtgpgzgDiDGEAEAhATgewNYWEg3gLABQSSALgJ4zIAaSAvARAB7gwA2EAXEgEQAxAJYQOAEz4BfJADIkwAK5gARhDQBtALoBuEiTLwMwKOSQte9JkVJkkAOgfqAjABokAJk0v9t1uy68giLifN420iBQSIbG5LrEknrEoJCwCMgA6hhoWFHWZFQ0SJbMbGCcPPzCohLScooqalrxPjEmZowEPmQOds5unmG2SH7lAVXBEkNIEVFtcUkGRu2UFp0s8ZJAA

Comienza con el TypeScript Playground enlazado y reproduce las dos formas de asignación mostradas en el issue. Sigue el recorrido de comprobación de tipos para los tipos intersección, los spreads de arrays o tuplas y las asignaciones de literales de objeto; se considera terminado cuando el comportamiento está explicado y, si se confirma que es un bug, una prueba de regresión captura el resultado esperado.