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// Number.isNaN as it is not supported in IE11 so conditionally using ponyfill
// Using Number.isNaN where possible as it is ~10% faster
const safeIsNaN =
Number.isNaN ||
function ponyfill(value: unknown): boolean {
// // https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Number/isNaN#polyfill
// NaN is the only value in JavaScript which is not equal to itself.
return typeof value === 'number' && value !== value;
};
function isEqual(first: unknown, second: unknown): boolean {
if (first === second) {
return true;
}
// Special case for NaN (NaN !== NaN)
if (safeIsNaN(first) && safeIsNaN(second)) {
return true;
}
return false;
}
export default function areInputsEqual(
newInputs: readonly unknown[],
lastInputs: readonly unknown[],
): boolean {
// no checks needed if the inputs length has changed
if (newInputs.length !== lastInputs.length) {
return false;
}
// Using for loop for speed. It generally performs better than array.every
// https://github.com/alexreardon/memoize-one/pull/59
for (let i = 0; i < newInputs.length; i++) {
if (!isEqual(newInputs[i], lastInputs[i])) {
return false;
}
}
return true;
}