no-if.md

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:

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:

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.