source: trip-planner-front/node_modules/webpack/lib/UseStrictPlugin.js

/*
        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;