import { test } from "node:test";

import assert from "node:assert/strict";

import { alignLines } from "../out/diffutil.mjs";

test("alignLines maps unchanged lines through insertions and deletions", () => {

  const before = ["a", "b", "c", "d", "e"];

  const after = ["a", "x", "b", "d", "e", "f"];

  assert.deepEqual(alignLines(before, after), [0, -1, 1, 3, 4, -1]);

  assert.deepEqual(alignLines([], ["a"]), [-1]);

  assert.deepEqual(alignLines(["a"], []), []);

  assert.deepEqual(alignLines(["same", "same"], ["same", "same"]), [0, 1]);

  const moved = alignLines(["1", "2", "3", "4"], ["3", "4", "1", "2"]);

  assert.equal(moved.filter((i) => i >= 0).length, 2, "one block matches, the other reads as moved");

});