Promise chains aren't being executed all the way through - node.js

Question

I'm trying to do an integration test on a function that manages users. The calls it makes are asynchronous but Jest seems to be cutting out after I add the test user and check the details.
it("runs lifecycle", async done => {
// expect.assertions(1);
function check(a, b, c) {
return new Promise((resolve, reject) => {
console.log(a, b, c);
if (a != b) reject(c);
console.error(a, b, c);
resolve();
});
}
await new Promise((resolve, reject) => {
user.add(testUser).then(() => {
user.get(testUser.id).then(out => {
check(out, testUser, "adding").then(() => {
user.update(testUser1).then(() => {
user
.get(testUser1.id)
.then(out => check(out, testUser1, "update"))
.then(() => {
user.delete(testUser.id).then(() => {
user
.get(testUser1.id)
.then(out => check(out, null, "delete"))
.then(() => {
resolve();
done();
});
});
});
});
});
});
});
}).then(() => {
expect(true).toBeTruthy;
done();
});
done();
testUser and testUser1 are objects with some of their properties changed. I have tested this outside of Jest and the code runs fine.
console.log user.js:68
Successfully created new user: test
console.log user.test.js:26
{ id: 'test',
email: 'you#me.com',
first: 'Wilhelm',
last: 'Erasmus',
phone: '[phone]' } { id: 'test',
email: 'yo#me.com',
first: 'Wilhelm',
last: 'Erasmus',
phone: '[phone]' } 'adding'
console.error user.test.js:28
{ id: 'test',
email: 'you#me.com',
first: 'Wilhelm',
last: 'Erasmus',
phone: '[phone]' } { id: 'test',
email: 'yo#me.com',
first: 'Wilhelm',
last: 'Erasmus',
phone: '[phone]' } 'adding'
FAIL ./user.test.js (7.269s)
User APIs
✕ runs lifecycle (2779ms)
● User APIs › runs lifecycle
Error
adding
----------|----------|----------|----------|----------|-------------------|
File | % Stmts | % Branch | % Funcs | % Lines | Uncovered Line #s |
----------|----------|----------|----------|----------|-------------------|
All files | Unknown | Unknown | Unknown | Unknown | |
----------|----------|----------|----------|----------|-------------------|
Test Suites: 1 failed, 1 total
Tests: 1 failed, 1 total
Snapshots: 0 total
Time: 9.916s
Ran all test suites.
console.log user.js:114
Successfully deleted test
Jest did not exit one second after the test run has completed.
This usually means that there are asynchronous operations that weren't stopped in your tests. Consider running Jest with `--detectOpenHandles` to troubleshoot this issue.

Answer 1

I fixed the problem. I'm not sure why this solution works and I am happy to accept an answer that explains it better.
var addUser = user.add(testUser);
var checkAdd = addUser
.then(() => user.get(testUser.id))
.then(check1 => check(check1, testUser, "Add"));
var updateUser = checkAdd.then(() => user.update(testUser1));
var checkUpdate = updateUser
.then(() => user.get(testUser1.id))
.then(check2 => check(check2, testUser1, "Add"));
var deleteUser = checkUpdate.then(() => user.delete(testUser1.id));
var checkDelete = deleteUser.then(() => {
expect(user.exists).resolves.toBeFalsy;
});
return Promise.all([
addUser,
checkAdd,
updateUser,
checkUpdate,
deleteUser,
checkDelete
]);