mappingOf(
          sourceCodePoint0 = 0,
          sourceCodePoint1 = 0,
          mappedToCodePoints = listOf(1 shl 18),
        ),
      ),
    ).isEqualTo(null)
  }

  private fun mappingOf(
    sourceCodePoint0: Int,
    sourceCodePoint1: Int,
    mappedToCodePoints: List<Int>,
  ): Mapping =
    Mapping(
      sourceCodePoint0 = sourceCodePoint0,

      if (type == TYPE_MAPPED && mappedTo != next.mappedTo) break

      unionWith = next
      index++
    }

    result +=
      Mapping(
        sourceCodePoint0 = mapping.sourceCodePoint0,
        sourceCodePoint1 = unionWith.sourceCodePoint1,
        type = type,
        mappedTo = mappedTo,
      )
  }

  return result
}