original()

original(draft) returns the value that a draft was created from: the object of the base state, without the changes that the recipe has made to it.

original<T>(draft: T): T

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import { create, original } from 'mutative';

const baseState = {
  foo: 'bar',
  list: [{ text: 'todo' }],
};

const state = create(baseState, (draft) => {
  draft.foo = 'foobar';
  draft.list.push({ text: 'learning' });

  expect(original(draft.list)).toEqual([{ text: 'todo' }]);
  expect(original(draft.list)).toBe(baseState.list);
  expect(original(draft.list)).not.toBe(draft.list);
});

Use it to compare a draft with its original value, or to read the base state without creating drafts, since the original value holds no proxies.

• original() returns the object of the base state itself, so never change it.
• It throws for a value that is not a draft, such as the base state, a finished state, or a value that the recipe assigned, which Mutative does not draft. Use isDraft() to check.
• An object of the base state is drafted when the recipe reads it, so a search of a draft array for such an object does not find it; search original(draft.list) for it, as in original(draft.list).indexOf(item).

original() reflects the state before the recipe's changes, so an index found in original(draft.list) no longer matches the draft once the recipe has added, removed or moved elements. To search a draft array, use current().