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function canAccessProperty(base, property) {
let safe;
try {
safe = Boolean(base[property]);
} catch (error) {
safe = false;
}
return safe;
}
function canCallFunction(base, functionName, ...args) {
let safe = true;
try {
base[functionName](...args);
} catch (error) {
safe = false;
}
return safe;
}
/**
* Determines if `window.localStorage` is available and
* can be written to and read from.
*
* Important: This is not a guarantee that
* `localStorage.setItem` will work in all cases.
*
* `setItem` can still throw exceptions and should be
* surrounded with a try/catch where used.
*
* See: https://developer.mozilla.org/en-US/docs/Web/API/Storage/setItem#exceptions
*/
function canUseLocalStorage() {
let safe;
const TEST_KEY = 'canUseLocalStorage';
const TEST_VALUE = 'true';
safe = canAccessProperty(window, 'localStorage');
if (!safe) return safe;
safe = canCallFunction(window.localStorage, 'setItem', TEST_KEY, TEST_VALUE);
if (safe) window.localStorage.removeItem(TEST_KEY);
return safe;
}
/**
* Determines if `window.crypto` is available.
*/
function canUseCrypto() {
return window.crypto?.subtle !== undefined;
}
const AccessorUtilities = {
canUseLocalStorage,
canUseCrypto,
};
export default AccessorUtilities;
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