Function diff

packages/effect/src/internal/differ/readonlyArrayPatch.ts:116–141

(
  options: {
    readonly oldValue: ReadonlyArray<Value>
    readonly newValue: ReadonlyArray<Value>
    readonly differ: Differ.Differ<Value, Patch>
  }
)

/** @internal */
export const diff = <Value, Patch>(
  options: {
    readonly oldValue: ReadonlyArray<Value>
    readonly newValue: ReadonlyArray<Value>
    readonly differ: Differ.Differ<Value, Patch>
  }
): Differ.Differ.ReadonlyArray.Patch<Value, Patch> => {
  let i = 0
  let patch = empty<Value, Patch>()
  while (i < options.oldValue.length && i < options.newValue.length) {
    const oldElement = options.oldValue[i]!
    const newElement = options.newValue[i]!
    const valuePatch = options.differ.diff(oldElement, newElement)
    if (!Equal.equals(valuePatch, options.differ.empty)) {
      patch = combine(patch, makeUpdate(i, valuePatch))
    }
    i = i + 1
  }
  if (i < options.oldValue.length) {
    patch = combine(patch, makeSlice(0, i))
  }
  if (i < options.newValue.length) {
    patch = combine(patch, makeAppend(Arr.drop(i)(options.newValue)))
  }
  return patch
}

/** @internal */
export const combine = Dual.dual<