UseStrictPlugin.js
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	/*
	MIT License http://www.opensource.org/licenses/mit-license.php
	Author Tobias Koppers @sokra
	*/

	"use strict";

	const ConstDependency = require("./dependencies/ConstDependency");

	/** @typedef {import("./Compiler")} Compiler */

	class UseStrictPlugin {
	/**
	* Apply the plugin
	* @param {Compiler} compiler the compiler instance
	* @returns {void}
	*/
	apply(compiler) {
	compiler.hooks.compilation.tap(
	"UseStrictPlugin",
	(compilation, { normalModuleFactory }) => {
	const handler = parser => {
	parser.hooks.program.tap("UseStrictPlugin", ast => {
	const firstNode = ast.body[0];
	if (
	firstNode &&
	firstNode.type === "ExpressionStatement" &&
	firstNode.expression.type === "Literal" &&
	firstNode.expression.value === "use strict"
	) {
	// Remove "use strict" expression. It will be added later by the renderer again.
	// This is necessary in order to not break the strict mode when webpack prepends code.
	// @see https://github.com/webpack/webpack/issues/1970
	const dep = new ConstDependency("", firstNode.range);
	dep.loc = firstNode.loc;
	parser.state.module.addPresentationalDependency(dep);
	parser.state.module.buildInfo.strict = true;
	}
	});
	};

	normalModuleFactory.hooks.parser
	.for("javascript/auto")
	.tap("UseStrictPlugin", handler);
	normalModuleFactory.hooks.parser
	.for("javascript/dynamic")
	.tap("UseStrictPlugin", handler);
	normalModuleFactory.hooks.parser
	.for("javascript/esm")
	.tap("UseStrictPlugin", handler);
	}
	);
	}
	}

	module.exports = UseStrictPlugin;