spread-fences.ts:14:21 - error SC1090: conditional spreads beyond `...(c ? { field: v } : {})` (exactly one property against an empty arm — spell other shapes as optional fields) is not supported yet

  13 | const cond = true;
  14 | const s1: Shape = { ...(cond ? { x: 1, y: 2 } : { x: 3, y: 4 }) };
     |                     ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  15 | interface YOnly {

spread-fences.ts:19:27 - error SC1090: object spread after explicit properties (spreads must come first — a later spread would overwrite them with JS semantics the desugar does not model) are not supported yet

  18 | const yPart: YOnly = { y: 0 };
  19 | const s2: Shape = { x: 5, ...yPart };
     |                           ^~~~~~~~
  20 | // A spread field the target keeps (no later override) must match exactly —