node-postgres/packages/pg-cursor/test/close.js

const assert = require('assert');
const Cursor = require('../');
const pg = require('pg');

const text = 'SELECT generate_series as num FROM generate_series(0, 50)';
describe('close', function () {
  beforeEach(function (done) {
    const client = (this.client = new pg.Client());
    client.connect(done);
  });

  this.afterEach(function (done) {
    this.client.end(done);
  });

  it('can close a finished cursor without a callback', function (done) {
    const cursor = new Cursor(text);
    this.client.query(cursor);
    this.client.query('SELECT NOW()', done);
    cursor.read(100, function (err) {
      assert.ifError(err);
      cursor.close();
    });
  });

  it('closes cursor early', function (done) {
    const cursor = new Cursor(text);
    this.client.query(cursor);
    this.client.query('SELECT NOW()', done);
    cursor.read(25, function (err) {
      assert.ifError(err);
      cursor.close();
    });
  });

  it('works with callback style', function (done) {
    const cursor = new Cursor(text);
    const client = this.client;
    client.query(cursor);
    cursor.read(25, function (err, rows) {
      assert.ifError(err);
      assert.strictEqual(rows.length, 25);
      cursor.close(function (err) {
        assert.ifError(err);
        client.query('SELECT NOW()', done);
      });
    });
  });

  it('is a no-op to "close" the cursor before submitting it', function (done) {
    const cursor = new Cursor(text);
    cursor.close(done);
  });
});