2018-10-10 22:03:03 +00:00
---
id: 587d824b367417b2b2512c47
2021-02-06 04:42:36 +00:00
title: Test if a Variable or Function is Defined
2018-10-10 22:03:03 +00:00
challengeType: 2
2020-09-17 10:50:23 +00:00
forumTopicId: 301602
2021-01-13 02:31:00 +00:00
dashedName: test-if-a-variable-or-function-is-defined
2018-10-10 22:03:03 +00:00
---
2020-12-16 07:37:30 +00:00
# --description--
2021-02-06 04:42:36 +00:00
As a reminder, this project is being built upon the following starter project on [Repl.it ](https://repl.it/github/freeCodeCamp/boilerplate-mochachai ), or cloned from [GitHub ](https://github.com/freeCodeCamp/boilerplate-mochachai/ ).
2020-09-17 10:50:23 +00:00
2020-12-16 07:37:30 +00:00
# --instructions--
2018-10-10 22:03:03 +00:00
2021-02-06 04:42:36 +00:00
Within `tests/1_unit-tests.js` under the test labelled `#2` in the `Basic Assertions` suite, change each `assert` to either `assert.isDefined()` or `assert.isUndefined()` to make the test pass (should evaluate to `true` ). Do not alter the arguments passed to the asserts.
2018-10-10 22:03:03 +00:00
2020-12-16 07:37:30 +00:00
# --hints--
2018-10-10 22:03:03 +00:00
2021-02-06 04:42:36 +00:00
All tests should pass.
2018-10-10 22:03:03 +00:00
2020-12-16 07:37:30 +00:00
```js
(getUserInput) =>
$.get(getUserInput('url') + '/_api/get-tests?type=unit& n=1').then(
(data) => {
assert.equal(data.state, 'passed');
},
(xhr) => {
throw new Error(xhr.responseText);
}
);
2018-10-10 22:03:03 +00:00
```
2021-02-06 04:42:36 +00:00
You should choose the correct method for the first assertion - `isDefined` vs. `isUndefined` .
2020-12-16 07:37:30 +00:00
```js
(getUserInput) =>
$.get(getUserInput('url') + '/_api/get-tests?type=unit& n=1').then(
(data) => {
assert.equal(
data.assertions[0].method,
'isDefined',
'Null is not undefined'
);
},
(xhr) => {
throw new Error(xhr.responseText);
}
);
```
2018-10-10 22:03:03 +00:00
2021-02-06 04:42:36 +00:00
You should choose the correct method for the second assertion - `isDefined` vs. `isUndefined` .
2018-10-10 22:03:03 +00:00
2020-12-16 07:37:30 +00:00
```js
(getUserInput) =>
$.get(getUserInput('url') + '/_api/get-tests?type=unit& n=1').then(
(data) => {
assert.equal(
data.assertions[1].method,
'isUndefined',
'Undefined is undefined'
);
},
(xhr) => {
throw new Error(xhr.responseText);
}
);
```
2018-10-10 22:03:03 +00:00
2021-02-06 04:42:36 +00:00
You should choose the correct method for the third assertion - `isDefined` vs. `isUndefined` .
2018-10-10 22:03:03 +00:00
```js
2020-12-16 07:37:30 +00:00
(getUserInput) =>
$.get(getUserInput('url') + '/_api/get-tests?type=unit& n=1').then(
(data) => {
assert.equal(
data.assertions[2].method,
'isDefined',
'A string is not undefined'
);
},
(xhr) => {
throw new Error(xhr.responseText);
}
);
2018-10-10 22:03:03 +00:00
```
2020-08-13 15:24:35 +00:00
2020-12-16 07:37:30 +00:00
# --solutions--
2021-01-13 02:31:00 +00:00
```js
/**
Backend challenges don't need solutions,
because they would need to be tested against a full working project.
Please check our contributing guidelines to learn more.
*/
```