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node_modules/webpack/lib/serialization/PlainObjectSerializer.js

@@ -0,0 +1,80 @@
+/*
+	MIT License http://www.opensource.org/licenses/mit-license.php
+*/
+
+"use strict";
+
+const cache = new WeakMap();
+
+class ObjectStructure {
+	constructor() {
+		this.keys = undefined;
+		this.children = undefined;
+	}
+
+	getKeys(keys) {
+		if (this.keys === undefined) this.keys = keys;
+		return this.keys;
+	}
+
+	key(key) {
+		if (this.children === undefined) this.children = new Map();
+		const child = this.children.get(key);
+		if (child !== undefined) return child;
+		const newChild = new ObjectStructure();
+		this.children.set(key, newChild);
+		return newChild;
+	}
+}
+
+const getCachedKeys = (keys, cacheAssoc) => {
+	let root = cache.get(cacheAssoc);
+	if (root === undefined) {
+		root = new ObjectStructure();
+		cache.set(cacheAssoc, root);
+	}
+	let current = root;
+	for (const key of keys) {
+		current = current.key(key);
+	}
+	return current.getKeys(keys);
+};
+
+class PlainObjectSerializer {
+	serialize(obj, { write }) {
+		const keys = Object.keys(obj);
+		if (keys.length > 128) {
+			// Objects with so many keys are unlikely to share structure
+			// with other objects
+			write(keys);
+			for (const key of keys) {
+				write(obj[key]);
+			}
+		} else if (keys.length > 1) {
+			write(getCachedKeys(keys, write));
+			for (const key of keys) {
+				write(obj[key]);
+			}
+		} else if (keys.length === 1) {
+			const key = keys[0];
+			write(key);
+			write(obj[key]);
+		} else {
+			write(null);
+		}
+	}
+	deserialize({ read }) {
+		const keys = read();
+		const obj = {};
+		if (Array.isArray(keys)) {
+			for (const key of keys) {
+				obj[key] = read();
+			}
+		} else if (keys !== null) {
+			obj[keys] = read();
+		}
+		return obj;
+	}
+}
+
+module.exports = PlainObjectSerializer;