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'use strict';
const assert = require('assert');const mongoose = require('../../');const start = require('../common');
describe('defaults docs', function() {  let db;  const Schema = mongoose.Schema;
  before(function() {    db = mongoose.createConnection(start.uri);  });
  after(async function() {    await db.close();  });
  afterEach(function() {    db.models = {};  });
  /**   * Your schemas can define default values for certain paths. If you create   * a new document without that path set, the default will kick in.   *   * Note: Mongoose only applies a default if the value of the path is   * strictly `undefined`.   */  it('Declaring defaults in your schema', async function() {    const schema = new Schema({      name: String,      role: { type: String, default: 'guitarist' }    });
    const Person = db.model('Person', schema);
    const axl = new Person({ name: 'Axl Rose', role: 'singer' });    assert.equal(axl.role, 'singer');
    const slash = new Person({ name: 'Slash' });    assert.equal(slash.role, 'guitarist');
    const izzy = new Person({ name: 'Izzy', role: undefined });    assert.equal(izzy.role, 'guitarist');
    // Defaults do **not** run on `null`, `''`, or value other than `undefined`.    const foo = new Person({ name: 'Bar', role: null });    assert.strictEqual(foo.role, null);
    await Person.create(axl, slash);        const docs = await Person.find({ role: 'guitarist' });        assert.equal(docs.length, 1);    assert.equal(docs[0].name, 'Slash');  });
  /**   * You can also set the `default` schema option to a function. Mongoose will   * execute that function and use the return value as the default.   */  it('Default functions', function() {    const schema = new Schema({      title: String,      date: {        type: Date,        // `Date.now()` returns the current unix timestamp as a number        default: Date.now      }    });
    const BlogPost = db.model('BlogPost', schema);
    const post = new BlogPost({ title: '5 Best Arnold Schwarzenegger Movies' });
    // The post has a default Date set to now    assert.ok(post.date.getTime() >= Date.now() - 1000);    assert.ok(post.date.getTime() <= Date.now());  });
  /**   * Mongoose also applies defaults when you upsert a document.   * Mongoose only applies defaults on upsert if a new document is   * inserted, not if the upsert updated an existing document.   *   */  it('The `setDefaultsOnInsert` option', async function() {    const schema = new Schema({      title: String,      genre: { type: String, default: 'Action' }    });
    const Movie = db.model('Movie', schema);    // acquit:ignore:start    await Movie.deleteMany({});    // acquit:ignore:end
    const query = {};    const update = { title: 'The Terminator' };    const options = {      // Return the document after updates are applied      new: true,      // Create a document if one isn't found.      upsert: true    };
    let doc = await Movie.findOneAndUpdate(query, update, options).lean();    doc.genre; // 'Action', Mongoose set a default value.    // acquit:ignore:start    assert.equal(doc.title, 'The Terminator');    assert.equal(doc.genre, 'Action');    // acquit:ignore:end
    await Movie.deleteMany({});
    doc = await Movie.findOneAndUpdate(query, update, { new: true, upsert: true, setDefaultsOnInsert: false }).lean();    doc.genre; // undefined, Mongoose did not set a default value    // acquit:ignore:start    assert.equal(doc.title, 'The Terminator');    assert.equal(doc.genre, void 0);    // acquit:ignore:end  });
  /**   * Unless it is running on a query with `setDefaultsOnInsert`, a default   * function's `this` refers to the document.   */  it('Default functions and `this`', function() {    const schema = new Schema({      title: String,      released: Boolean,      releaseDate: {        type: Date,        default: function() {          if (this.released) {            return Date.now();          }          return null;        }      }    });
    const Movie = db.model('Movie', schema);
    const movie1 = new Movie({ title: 'The Terminator', released: true });
    // The post has a default Date set to now    assert.ok(movie1.releaseDate.getTime() >= Date.now() - 1000);    assert.ok(movie1.releaseDate.getTime() <= Date.now());
    const movie2 = new Movie({ title: 'The Legend of Conan', released: false });
    // Since `released` is false, the default function will return null    assert.strictEqual(movie2.releaseDate, null);  });});