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'use strict';
const assert = require('assert');const start = require('../common');
const mongoose = new start.mongoose.Mongoose();const Schema = mongoose.Schema;
// This file is in `es-next` because it uses async/await for convenience
describe('Virtuals', function() {  before(async function() {    await mongoose.connect(start.uri);  });
  beforeEach(function() {    mongoose.deleteModel(/.*/);  });
  it('basic', async function() {    const userSchema = mongoose.Schema({      email: String    });    // Create a virtual property `domain` that's computed from `email`.    userSchema.virtual('domain').get(function() {      return this.email.slice(this.email.indexOf('@') + 1);    });    const User = mongoose.model('User', userSchema);
    let doc = await User.create({ email: 'test@gmail.com' });    // `domain` is now a property on User documents.    doc.domain; // 'gmail.com'    // acquit:ignore:start    assert.equal(doc.domain, 'gmail.com');    // acquit:ignore:end  });
  it('fullName', async function() {    const userSchema = mongoose.Schema({      firstName: String,      lastName: String    });    // Create a virtual property `fullName` with a getter and setter.    userSchema.virtual('fullName').      get(function() { return `${this.firstName} ${this.lastName}`; }).      set(function(v) {        // `v` is the value being set, so use the value to set        // `firstName` and `lastName`.        const firstName = v.substring(0, v.indexOf(' '));        const lastName = v.substring(v.indexOf(' ') + 1);        this.set({ firstName, lastName });      });    const User = mongoose.model('User', userSchema);
    const doc = new User();    // Vanilla JavaScript assignment triggers the setter    doc.fullName = 'Jean-Luc Picard';
    doc.fullName; // 'Jean-Luc Picard'    doc.firstName; // 'Jean-Luc'    doc.lastName; // 'Picard'    // acquit:ignore:start    assert.equal(doc.fullName, 'Jean-Luc Picard');    assert.equal(doc.firstName, 'Jean-Luc');    assert.equal(doc.lastName, 'Picard');    // acquit:ignore:end  });
  it('toJSON', async function() {    const opts = { toJSON: { virtuals: true } };    const userSchema = mongoose.Schema({      _id: Number,      email: String    }, opts);    // Create a virtual property `domain` that's computed from `email`.    userSchema.virtual('domain').get(function() {      return this.email.slice(this.email.indexOf('@') + 1);    });    const User = mongoose.model('User', userSchema);
    const doc = new User({ _id: 1, email: 'test@gmail.com' });        doc.toJSON().domain; // 'gmail.com'    // {"_id":1,"email":"test@gmail.com","domain":"gmail.com","id":"1"}    JSON.stringify(doc); 
    // To skip applying virtuals, pass `virtuals: false` to `toJSON()`    doc.toJSON({ virtuals: false }).domain; // undefined    // acquit:ignore:start    assert.equal(doc.toJSON().domain, 'gmail.com');    assert.equal(JSON.stringify(doc),      '{"_id":1,"email":"test@gmail.com","domain":"gmail.com","id":"1"}');    assert.equal(doc.toJSON({ virtuals: false }).domain, void 0);    // acquit:ignore:end  });
  it('lean', async function() {    // acquit:ignore:start    const userSchema = mongoose.Schema({      email: String    });    // Create a virtual property `domain` that's computed from `email`.    userSchema.virtual('domain').get(function() {      return this.email.slice(this.email.indexOf('@') + 1);    });    const User = mongoose.model('User', userSchema);    await User.deleteMany({});    await User.create({ email: 'test@gmail.com' });    // acquit:ignore:end    const fullDoc = await User.findOne();    fullDoc.domain; // 'gmail.com'
    const leanDoc = await User.findOne().lean();    leanDoc.domain; // undefined    // acquit:ignore:start    assert.equal(fullDoc.domain, 'gmail.com');    assert.equal(leanDoc.domain, void 0);    // acquit:ignore:end  });
  it('in query', async function() {    // acquit:ignore:start    const userSchema = mongoose.Schema({      email: String    });    // Create a virtual property `domain` that's computed from `email`.    userSchema.virtual('domain').get(function() {      return this.email.slice(this.email.indexOf('@') + 1);    });    const User = mongoose.model('User', userSchema);    await User.deleteMany({});    await User.create({ email: 'test@gmail.com' });    // acquit:ignore:end    // Will **not** find any results, because `domain` is not stored in    // MongoDB.    const doc = await User.findOne({ domain: 'gmail.com' }, null, { strictQuery: false });    doc; // undefined    // acquit:ignore:start    assert.equal(doc, null);    // acquit:ignore:end  });
  it('populate', async function() {    const userSchema = mongoose.Schema({ _id: Number, email: String });    const blogPostSchema = mongoose.Schema({      title: String,      authorId: Number    });    // When you `populate()` the `author` virtual, Mongoose will find the    // first document in the User model whose `_id` matches this document's    // `authorId` property.    blogPostSchema.virtual('author', {      ref: 'User',      localField: 'authorId',      foreignField: '_id',      justOne: true    });    const User = mongoose.model('User', userSchema);    const BlogPost = mongoose.model('BlogPost', blogPostSchema);
    // acquit:ignore:start    await BlogPost.deleteMany({});    await User.deleteMany({});    // acquit:ignore:end    await BlogPost.create({ title: 'Introduction to Mongoose', authorId: 1 });    await User.create({ _id: 1, email: 'test@gmail.com' });
    const doc = await BlogPost.findOne().populate('author');    doc.author.email; // 'test@gmail.com'    // acquit:ignore:start    assert.equal(doc.author.email, 'test@gmail.com');    // acquit:ignore:end  });});