Cannot Build loopback4 app without errors

[frost-byte]

Description / Steps to reproduce / Feature proposal

Install LoopBack4
Run lb4 app
Enable all options (specifically tests)

Current Behavior

During the build, when the command tsc --outDir dist --target es2017 runs,
nine errors appear, all related to @types/jest, jest and @types/mocha, mocha

src/__tests__/acceptance/home-page.acceptance.ts:5:1 - error TS2582: Cannot find name 'describe'. Do you need to install type definitions for a test runner? Try `npm i @types/jest` or `npm i @types/mocha`.

5 describe('HomePage', () => {


src/__tests__/acceptance/home-page.acceptance.ts:9:3 - error TS2304: Cannot find name 'before'.

9   before('setupApplication', async () => {

src/__tests__/acceptance/home-page.acceptance.ts:13:3 - error TS2304: Cannot find name 'after'.

13   after(async () => {

src/__tests__/acceptance/home-page.acceptance.ts:17:3 - error TS2582: Cannot find name 'it'. Do you need to install type definitions for a test runner? Try `npm i @types/jest` or `npm i @types/mocha`.

17   it('exposes a default home page', async () => {

src/__tests__/acceptance/home-page.acceptance.ts:24:3 - error TS2582: Cannot find name 'it'. Do you need to install type definitions for a test runner? Try `npm i @types/jest` or `npm i @types/mocha`.

24   it('exposes self-hosted explorer', async () => {

src/__tests__/acceptance/ping.controller.acceptance.ts:5:1 - error TS2582: Cannot find name 'describe'. Do you need to install type definitions for a test runner? Try `npm i @types/jest` or `npm i @types/mocha`.

5 describe('PingController', () => {

src/__tests__/acceptance/ping.controller.acceptance.ts:9:3 - error TS2304: Cannot find name 'before'.

9   before('setupApplication', async () => {

src/__tests__/acceptance/ping.controller.acceptance.ts:13:3 - error TS2304: Cannot find name 'after'.

13   after(async () => {

src/__tests__/acceptance/ping.controller.acceptance.ts:17:3 - error TS2582: Cannot find name 'it'. Do you need to install type definitions for a test runner? Try `npm i @types/jest` or `npm i @types/mocha`.

17   it('invokes GET /ping', async () => {

Found 9 errors.

Expected Behavior

The build completes without any errors thrown by typescript when the tests are built.

Observations

I did not see anything in the documentation saying that I should globally install mocha, jest and the relevant type files. Installing them globally, or locally in the project directory and then running the command to build the tests then completes without throwing any errors.
Edit Installing mocha, jest and the @types for them does not fix the issue. Deleting the app and recreating it using lb4 appName still shows the same errors. The only way to fix the issues is to install them as dependencies in the project

Environment

Ubuntu 18.04.2 LTS
npm v6.7.0
nodejs 11.14.0

[dhmlau]

@frost-byte , you're right that you don't need to install mocha globally. I assume you accept all options when running lb4 app to create the app?
Could you please check whether you have node_modules folder in the parent directories?
Your error is not the same as #2611, but removing node_modules in the parent directories might help. Thanks.

[dhmlau]

@frost-byte, does the above suggestion help in getting rid of the error? Thanks.

[dhmlau]

Closing due to inactivity.

[pSnehanshu]

I am having the same issue.
Running npm install gives this:

> office-rent-backend@1.0.0 prepare /home/snehanshu/Desktop/office-rent-backend
> npm run build


> office-rent-backend@1.0.0 build /home/snehanshu/Desktop/office-rent-backend
> tsc

src/__tests__/acceptance/home-page.acceptance.ts:5:1 - error TS2582: Cannot find name 'describe'. Do you need to install type definitions for a test runner? Try `npm i @types/jest` or `npm i @types/mocha`.

5 describe('HomePage', () => {
  ~~~~~~~~

src/__tests__/acceptance/home-page.acceptance.ts:9:3 - error TS2304: Cannot find name 'before'.

9   before('setupApplication', async () => {
    ~~~~~~

src/__tests__/acceptance/home-page.acceptance.ts:13:3 - error TS2304: Cannot find name 'after'.

13   after(async () => {
     ~~~~~

src/__tests__/acceptance/home-page.acceptance.ts:17:3 - error TS2582: Cannot find name 'it'. Do you need to install type definitions for a test runner? Try `npm i @types/jest` or `npm i @types/mocha`.

17   it('exposes a default home page', async () => {
     ~~

src/__tests__/acceptance/home-page.acceptance.ts:24:3 - error TS2582: Cannot find name 'it'. Do you need to install type definitions for a test runner? Try `npm i @types/jest` or `npm i @types/mocha`.

24   it('exposes self-hosted explorer', async () => {
     ~~

src/__tests__/acceptance/ping.controller.acceptance.ts:5:1 - error TS2582: Cannot find name 'describe'. Do you need to install type definitions for a test runner? Try `npm i @types/jest` or `npm i @types/mocha`.

5 describe('PingController', () => {
  ~~~~~~~~

src/__tests__/acceptance/ping.controller.acceptance.ts:9:3 - error TS2304: Cannot find name 'before'.

9   before('setupApplication', async () => {
    ~~~~~~

src/__tests__/acceptance/ping.controller.acceptance.ts:13:3 - error TS2304: Cannot find name 'after'.

13   after(async () => {
     ~~~~~

src/__tests__/acceptance/ping.controller.acceptance.ts:17:3 - error TS2582: Cannot find name 'it'. Do you need to install type definitions for a test runner? Try `npm i @types/jest` or `npm i @types/mocha`.

17   it('invokes GET /ping', async () => {
     ~~


Found 9 errors.

npm ERR! code ELIFECYCLE
npm ERR! errno 2
npm ERR! office-rent-backend@1.0.0 build: `tsc`
npm ERR! Exit status 2
npm ERR! 
npm ERR! Failed at the office-rent-backend@1.0.0 build script.
npm ERR! This is probably not a problem with npm. There is likely additional logging output above.

npm ERR! A complete log of this run can be found in:
npm ERR!     /home/snehanshu/.npm/_logs/2019-11-04T18_35_49_946Z-debug.log
npm ERR! code ELIFECYCLE
npm ERR! errno 2
npm ERR! office-rent-backend@1.0.0 prepare: `npm run build`
npm ERR! Exit status 2
npm ERR! 
npm ERR! Failed at the office-rent-backend@1.0.0 prepare script.
npm ERR! This is probably not a problem with npm. There is likely additional logging output above.

npm ERR! A complete log of this run can be found in:
npm ERR!     /home/snehanshu/.npm/_logs/2019-11-04T18_35_49_961Z-debug.log

[pSnehanshu]

Installing @types/jest and @types/mocha solved the issue, wondering why they aren't installed by default.