denoland-deno/tests/node_compat/test/parallel/test-stream-transform-final.js

// deno-fmt-ignore-file
// deno-lint-ignore-file

// Copyright Joyent and Node contributors. All rights reserved. MIT license.
// Taken from Node 18.12.1
// This file is automatically generated by `tests/node_compat/runner/setup.ts`. Do not modify this file manually.

'use strict';
const common = require('../common');
const assert = require('assert');

const stream = require('stream');
let state = 0;


// What you do:
//
// const stream = new stream.Transform({
//   transform: function transformCallback(chunk, _, next) {
//     // part 1
//     this.push(chunk);
//     //part 2
//     next();
//   },
//   final: function endCallback(done) {
//     // part 1
//     process.nextTick(function () {
//       // part 2
//       done();
//     });
//   },
//   flush: function flushCallback(done) {
//     // part 1
//     process.nextTick(function () {
//       // part 2
//       done();
//     });
//   }
// });
// t.on('data', dataListener);
// t.on('end', endListener);
// t.on('finish', finishListener);
// t.write(1);
// t.write(4);
// t.end(7, endMethodCallback);
//
// The order things are called

// 1. transformCallback part 1
// 2. dataListener
// 3. transformCallback part 2
// 4. transformCallback part 1
// 5. dataListener
// 6. transformCallback part 2
// 7. transformCallback part 1
// 8. dataListener
// 9. transformCallback part 2
// 10. finalCallback part 1
// 11. finalCallback part 2
// 12. flushCallback part 1
// 13. finishListener
// 14. endMethodCallback
// 15. flushCallback part 2
// 16. endListener

const t = new stream.Transform({
  objectMode: true,
  transform: common.mustCall(function(chunk, _, next) {
    // transformCallback part 1
    assert.strictEqual(++state, chunk);
    this.push(state);
    // transformCallback part 2
    assert.strictEqual(++state, chunk + 2);
    process.nextTick(next);
  }, 3),
  final: common.mustCall(function(done) {
    state++;
    // finalCallback part 1
    assert.strictEqual(state, 10);
    setTimeout(function() {
      state++;
      // finalCallback part 2
      assert.strictEqual(state, 11);
      done();
    }, 100);
  }, 1),
  flush: common.mustCall(function(done) {
    state++;
    // flushCallback part 1
    assert.strictEqual(state, 12);
    process.nextTick(function() {
      state++;
      // flushCallback part 2
      assert.strictEqual(state, 13);
      done();
    });
  }, 1)
});
t.on('finish', common.mustCall(function() {
  state++;
  // finishListener
  assert.strictEqual(state, 15);
}, 1));
t.on('end', common.mustCall(function() {
  state++;
  // end event
  assert.strictEqual(state, 16);
}, 1));
t.on('data', common.mustCall(function(d) {
  // dataListener
  assert.strictEqual(++state, d + 1);
}, 3));
t.write(1);
t.write(4);
t.end(7, common.mustCall(function() {
  state++;
  // endMethodCallback
  assert.strictEqual(state, 14);
}, 1));