1 files changed, 213 insertions, 0 deletions
diff --git a/node_modules/webpack/lib/util/WeakTupleMap.js b/node_modules/webpack/lib/util/WeakTupleMap.js
new file mode 100644
index 00000000..ac64e869
--- /dev/null
+++ b/node_modules/webpack/lib/util/WeakTupleMap.js
@@ -0,0 +1,213 @@
+/*
+	MIT License http://www.opensource.org/licenses/mit-license.php
+	Author Tobias Koppers @sokra
+*/
+
+"use strict";
+
+/**
+ * @template {any[]} T
+ * @template V
+ * @typedef {Map<object, WeakTupleMap<T, V>>} M
+ */
+/**
+ * @template {any[]} T
+ * @template V
+ * @typedef {WeakMap<object, WeakTupleMap<T, V>>} W
+ */
+
+/**
+ * @param {any} thing thing
+ * @returns {boolean} true if is weak
+ */
+const isWeakKey = thing => typeof thing === "object" && thing !== null;
+
+/**
+ * @template {any[]} T
+ * @template V
+ */
+class WeakTupleMap {
+	constructor() {
+		/** @private */
+		this.f = 0;
+		/**
+		 * @private
+		 * @type {any}
+		 */
+		this.v = undefined;
+		/**
+		 * @private
+		 * @type {M<T, V> | undefined}
+		 */
+		this.m = undefined;
+		/**
+		 * @private
+		 * @type {W<T, V> | undefined}
+		 */
+		this.w = undefined;
+	}
+
+	/**
+	 * @param {[...T, V]} args tuple
+	 * @returns {void}
+	 */
+	set(...args) {
+		/** @type {WeakTupleMap<T, V>} */
+		let node = this;
+		for (let i = 0; i < args.length - 1; i++) {
+			node = node._get(args[i]);
+		}
+		node._setValue(args[args.length - 1]);
+	}
+
+	/**
+	 * @param {T} args tuple
+	 * @returns {boolean} true, if the tuple is in the Set
+	 */
+	has(...args) {
+		/** @type {WeakTupleMap<T, V> | undefined} */
+		let node = this;
+		for (let i = 0; i < args.length; i++) {
+			node = node._peek(args[i]);
+			if (node === undefined) return false;
+		}
+		return node._hasValue();
+	}
+
+	/**
+	 * @param {T} args tuple
+	 * @returns {V | undefined} the value
+	 */
+	get(...args) {
+		/** @type {WeakTupleMap<T, V> | undefined} */
+		let node = this;
+		for (let i = 0; i < args.length; i++) {
+			node = node._peek(args[i]);
+			if (node === undefined) return;
+		}
+		return node._getValue();
+	}
+
+	/**
+	 * @param {[...T, function(): V]} args tuple
+	 * @returns {V} the value
+	 */
+	provide(...args) {
+		/** @type {WeakTupleMap<T, V>} */
+		let node = this;
+		for (let i = 0; i < args.length - 1; i++) {
+			node = node._get(args[i]);
+		}
+		if (node._hasValue()) return node._getValue();
+		const fn = args[args.length - 1];
+		const newValue = fn(...args.slice(0, -1));
+		node._setValue(newValue);
+		return newValue;
+	}
+
+	/**
+	 * @param {T} args tuple
+	 * @returns {void}
+	 */
+	delete(...args) {
+		/** @type {WeakTupleMap<T, V> | undefined} */
+		let node = this;
+		for (let i = 0; i < args.length; i++) {
+			node = node._peek(args[i]);
+			if (node === undefined) return;
+		}
+		node._deleteValue();
+	}
+
+	/**
+	 * @returns {void}
+	 */
+	clear() {
+		this.f = 0;
+		this.v = undefined;
+		this.w = undefined;
+		this.m = undefined;
+	}
+
+	_getValue() {
+		return this.v;
+	}
+
+	_hasValue() {
+		return (this.f & 1) === 1;
+	}
+
+	/**
+	 * @param {any} v value
+	 * @private
+	 */
+	_setValue(v) {
+		this.f |= 1;
+		this.v = v;
+	}
+
+	_deleteValue() {
+		this.f &= 6;
+		this.v = undefined;
+	}
+
+	/**
+	 * @param {any} thing thing
+	 * @returns {WeakTupleMap<T, V> | undefined} thing
+	 * @private
+	 */
+	_peek(thing) {
+		if (isWeakKey(thing)) {
+			if ((this.f & 4) !== 4) return;
+			return /** @type {W<T, V>} */ (this.w).get(thing);
+		}
+		if ((this.f & 2) !== 2) return;
+		return /** @type {M<T, V>} */ (this.m).get(thing);
+	}
+
+	/**
+	 * @private
+	 * @param {any} thing thing
+	 * @returns {WeakTupleMap<T, V>} value
+	 */
+	_get(thing) {
+		if (isWeakKey(thing)) {
+			if ((this.f & 4) !== 4) {
+				const newMap = new WeakMap();
+				this.f |= 4;
+				const newNode = new WeakTupleMap();
+				(this.w = newMap).set(thing, newNode);
+				return newNode;
+			}
+			const entry =
+				/** @type {W<T, V>} */
+				(this.w).get(thing);
+			if (entry !== undefined) {
+				return entry;
+			}
+			const newNode = new WeakTupleMap();
+			/** @type {W<T, V>} */
+			(this.w).set(thing, newNode);
+			return newNode;
+		}
+		if ((this.f & 2) !== 2) {
+			const newMap = new Map();
+			this.f |= 2;
+			const newNode = new WeakTupleMap();
+			(this.m = newMap).set(thing, newNode);
+			return newNode;
+		}
+		const entry =
+			/** @type {M<T, V>} */
+			(this.m).get(thing);
+		if (entry !== undefined) {
+			return entry;
+		}
+		const newNode = new WeakTupleMap();
+		/** @type {M<T, V>} */
+		(this.m).set(thing, newNode);
+		return newNode;
+	}
+}
+
+module.exports = WeakTupleMap;