setup-python/node_modules/define-properties/index.js

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2019-06-27 03:12:00 +02:00
'use strict';
var keys = require('object-keys');
var hasSymbols = typeof Symbol === 'function' && typeof Symbol('foo') === 'symbol';
var toStr = Object.prototype.toString;
var concat = Array.prototype.concat;
var origDefineProperty = Object.defineProperty;
var isFunction = function (fn) {
return typeof fn === 'function' && toStr.call(fn) === '[object Function]';
};
var arePropertyDescriptorsSupported = function () {
var obj = {};
try {
origDefineProperty(obj, 'x', { enumerable: false, value: obj });
// eslint-disable-next-line no-unused-vars, no-restricted-syntax
for (var _ in obj) { // jscs:ignore disallowUnusedVariables
return false;
}
return obj.x === obj;
} catch (e) { /* this is IE 8. */
return false;
}
};
var supportsDescriptors = origDefineProperty && arePropertyDescriptorsSupported();
var defineProperty = function (object, name, value, predicate) {
if (name in object && (!isFunction(predicate) || !predicate())) {
return;
}
if (supportsDescriptors) {
origDefineProperty(object, name, {
configurable: true,
enumerable: false,
value: value,
writable: true
});
} else {
object[name] = value;
}
};
var defineProperties = function (object, map) {
var predicates = arguments.length > 2 ? arguments[2] : {};
var props = keys(map);
if (hasSymbols) {
props = concat.call(props, Object.getOwnPropertySymbols(map));
}
for (var i = 0; i < props.length; i += 1) {
defineProperty(object, props[i], map[props[i]], predicates[props[i]]);
}
};
defineProperties.supportsDescriptors = !!supportsDescriptors;
module.exports = defineProperties;