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-rw-r--r--node_modules/react-dom/lib/accumulateInto.js57
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diff --git a/node_modules/react-dom/lib/accumulateInto.js b/node_modules/react-dom/lib/accumulateInto.js
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+/**
+ * Copyright 2014-present, Facebook, Inc.
+ * All rights reserved.
+ *
+ * This source code is licensed under the BSD-style license found in the
+ * LICENSE file in the root directory of this source tree. An additional grant
+ * of patent rights can be found in the PATENTS file in the same directory.
+ *
+ *
+ */
+
+'use strict';
+
+var _prodInvariant = require('./reactProdInvariant');
+
+var invariant = require('fbjs/lib/invariant');
+
+/**
+ * Accumulates items that must not be null or undefined into the first one. This
+ * is used to conserve memory by avoiding array allocations, and thus sacrifices
+ * API cleanness. Since `current` can be null before being passed in and not
+ * null after this function, make sure to assign it back to `current`:
+ *
+ * `a = accumulateInto(a, b);`
+ *
+ * This API should be sparingly used. Try `accumulate` for something cleaner.
+ *
+ * @return {*|array<*>} An accumulation of items.
+ */
+
+function accumulateInto(current, next) {
+ !(next != null) ? process.env.NODE_ENV !== 'production' ? invariant(false, 'accumulateInto(...): Accumulated items must not be null or undefined.') : _prodInvariant('30') : void 0;
+
+ if (current == null) {
+ return next;
+ }
+
+ // Both are not empty. Warning: Never call x.concat(y) when you are not
+ // certain that x is an Array (x could be a string with concat method).
+ if (Array.isArray(current)) {
+ if (Array.isArray(next)) {
+ current.push.apply(current, next);
+ return current;
+ }
+ current.push(next);
+ return current;
+ }
+
+ if (Array.isArray(next)) {
+ // A bit too dangerous to mutate `next`.
+ return [current].concat(next);
+ }
+
+ return [current, next];
+}
+
+module.exports = accumulateInto; \ No newline at end of file