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avoid-inverted-boolean-checks

added in: 1.4.0
style
Pro+

Warns when a condition has an inverted check.

Inverted checks are harder to spot because of the single ! symbol, which completely inverts the condition. Removing inverted conditions helps other developers understand the code faster.

Example​

❌ Bad:

// LINT: Avoid inverted boolean checks. Try rewriting this expression.
if (!(x == 1)) {}

// LINT: Avoid inverted boolean checks. Try rewriting this expression.
if (!(x != 1)) {}

// LINT: Avoid inverted boolean checks. Try rewriting this expression.
var b = !(x != 1) ? 1 : 2;

// LINT: Avoid inverted boolean checks. Try rewriting this expression.
if (!(a > 4 && b < 2)) {}

✅ Good:

if (x != 1) {} // Correct, == is replaced with !=

if (x == 1) {}

var b = x == 1 ? 1 : 2;

if (a <= 4 || b >= 2) {}