настройка webpack

node_modules/webpack/lib/util/StackedSetMap.js

@@ -0,0 +1,142 @@
+/*
+	MIT License http://www.opensource.org/licenses/mit-license.php
+	Author Tobias Koppers @sokra
+*/
+"use strict";
+
+const util = require("util");
+
+const TOMBSTONE = {};
+const UNDEFINED_MARKER = {};
+
+class StackedSetMap {
+	constructor(parentStack) {
+		this.stack = parentStack === undefined ? [] : parentStack.slice();
+		this.map = new Map();
+		this.stack.push(this.map);
+	}
+
+	add(item) {
+		this.map.set(item, true);
+	}
+
+	set(item, value) {
+		this.map.set(item, value === undefined ? UNDEFINED_MARKER : value);
+	}
+
+	delete(item) {
+		if (this.stack.length > 1) {
+			this.map.set(item, TOMBSTONE);
+		} else {
+			this.map.delete(item);
+		}
+	}
+
+	has(item) {
+		const topValue = this.map.get(item);
+		if (topValue !== undefined) return topValue !== TOMBSTONE;
+		if (this.stack.length > 1) {
+			for (var i = this.stack.length - 2; i >= 0; i--) {
+				const value = this.stack[i].get(item);
+				if (value !== undefined) {
+					this.map.set(item, value);
+					return value !== TOMBSTONE;
+				}
+			}
+			this.map.set(item, TOMBSTONE);
+		}
+		return false;
+	}
+
+	get(item) {
+		const topValue = this.map.get(item);
+		if (topValue !== undefined) {
+			return topValue === TOMBSTONE || topValue === UNDEFINED_MARKER
+				? undefined
+				: topValue;
+		}
+		if (this.stack.length > 1) {
+			for (var i = this.stack.length - 2; i >= 0; i--) {
+				const value = this.stack[i].get(item);
+				if (value !== undefined) {
+					this.map.set(item, value);
+					return value === TOMBSTONE || value === UNDEFINED_MARKER
+						? undefined
+						: value;
+				}
+			}
+			this.map.set(item, TOMBSTONE);
+		}
+		return undefined;
+	}
+
+	_compress() {
+		if (this.stack.length === 1) return;
+		this.map = new Map();
+		for (const data of this.stack) {
+			for (const pair of data) {
+				if (pair[1] === TOMBSTONE) {
+					this.map.delete(pair[0]);
+				} else {
+					this.map.set(pair[0], pair[1]);
+				}
+			}
+		}
+		this.stack = [this.map];
+	}
+
+	asArray() {
+		this._compress();
+		return Array.from(this.map.entries(), pair => pair[0]);
+	}
+
+	asSet() {
+		return new Set(this.asArray());
+	}
+
+	asPairArray() {
+		this._compress();
+		return Array.from(this.map.entries(), pair =>
+			/** @type {[TODO, TODO]} */ (pair[1] === UNDEFINED_MARKER
+				? [pair[0], undefined]
+				: pair)
+		);
+	}
+
+	asMap() {
+		return new Map(this.asPairArray());
+	}
+
+	get size() {
+		this._compress();
+		return this.map.size;
+	}
+
+	createChild() {
+		return new StackedSetMap(this.stack);
+	}
+
+	get length() {
+		throw new Error("This is no longer an Array");
+	}
+
+	set length(value) {
+		throw new Error("This is no longer an Array");
+	}
+}
+
+// TODO remove in webpack 5
+StackedSetMap.prototype.push = util.deprecate(
+	/**
+	 * @deprecated
+	 * @this {StackedSetMap}
+	 * @param {any} item Item to add
+	 * @returns {void}
+	 */
+	function(item) {
+		this.add(item);
+	},
+	"This is no longer an Array: Use add instead."
+);
+
+module.exports = StackedSetMap;