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node_modules/core-js/modules/es.array.unshift.js

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+'use strict';
+var $ = require('../internals/export');
+var toObject = require('../internals/to-object');
+var lengthOfArrayLike = require('../internals/length-of-array-like');
+var setArrayLength = require('../internals/array-set-length');
+var deletePropertyOrThrow = require('../internals/delete-property-or-throw');
+var doesNotExceedSafeInteger = require('../internals/does-not-exceed-safe-integer');
+
+// IE8-
+var INCORRECT_RESULT = [].unshift(0) !== 1;
+
+// V8 ~ Chrome < 71 and Safari <= 15.4, FF < 23 throws InternalError
+var properErrorOnNonWritableLength = function () {
+  try {
+    // eslint-disable-next-line es/no-object-defineproperty -- safe
+    Object.defineProperty([], 'length', { writable: false }).unshift();
+  } catch (error) {
+    return error instanceof TypeError;
+  }
+};
+
+var FORCED = INCORRECT_RESULT || !properErrorOnNonWritableLength();
+
+// `Array.prototype.unshift` method
+// https://tc39.es/ecma262/#sec-array.prototype.unshift
+$({ target: 'Array', proto: true, arity: 1, forced: FORCED }, {
+  // eslint-disable-next-line no-unused-vars -- required for `.length`
+  unshift: function unshift(item) {
+    var O = toObject(this);
+    var len = lengthOfArrayLike(O);
+    var argCount = arguments.length;
+    if (argCount) {
+      doesNotExceedSafeInteger(len + argCount);
+      var k = len;
+      while (k--) {
+        var to = k + argCount;
+        if (k in O) O[to] = O[k];
+        else deletePropertyOrThrow(O, to);
+      }
+      for (var j = 0; j < argCount; j++) {
+        O[j] = arguments[j];
+      }
+    } return setArrayLength(O, len + argCount);
+  }
+});