unmarshal bitset ints like cbor does

core/encoding/json/unmarshal.odin

@@ -116,7 +116,30 @@ assign_int :: proc(val: any, i: $T) -> bool {
 	case int:     dst = int    (i)
 	case uint:    dst = uint   (i)
 	case uintptr: dst = uintptr(i)
-	case: return false
+	case:
+		ti := type_info_of(v.id)
+		if _, ok := ti.variant.(runtime.Type_Info_Bit_Set); ok {
+			do_byte_swap := !reflect.bit_set_is_big_endian(v)
+			switch ti.size * 8 {
+			case 0: // no-op.
+			case 8:
+				x := (^u8)(v.data)
+				x^ = u8(i)
+			case 16:
+				x := (^u16)(v.data)
+				x^ = do_byte_swap ? intrinsics.byte_swap(u16(i)) : u16(i)
+			case 32:
+				x := (^u32)(v.data)
+				x^ = do_byte_swap ? intrinsics.byte_swap(u32(i)) : u32(i)
+			case 64:
+				x := (^u64)(v.data)
+				x^ = do_byte_swap ? intrinsics.byte_swap(u64(i)) : u64(i)
+			case:
+				panic("unknown bit_size size")
+			}
+			return true
+		}
+		return false
 	}
 	return true
 }