github-pages-deploy-action/node_modules/eslint-plugin-jest/docs/rules/no-if.md
2020-03-06 22:45:40 -05:00

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# Disallow conditional logic. (no-if)
Conditional logic in tests is usually an indication that a test is attempting to
cover too much, and not testing the logic it intends to. Each branch of code
executing within an if statement will usually be better served by a test devoted
to it.
Conditionals are often used to satisfy the typescript type checker. In these
cases, using the non-null assertion operator (!) would be best.
## Rule Details
This rule prevents the use of if/ else statements and conditional (ternary)
operations in tests.
The following patterns are considered warnings:
```js
it('foo', () => {
if ('bar') {
// an if statement here is invalid
// you are probably testing too much
}
});
it('foo', () => {
const bar = foo ? 'bar' : null;
});
```
These patterns would not be considered warnings:
```js
it('foo', () => {
// only test the 'foo' case
});
it('bar', () => {
// test the 'bar' case separately
});
it('foo', () => {
function foo(bar) {
// nested functions are valid
return foo ? bar : null;
}
});
```
## When Not To Use It
If you do not wish to prevent the use of if statements in tests, you can safely
disable this rule.