Method installPackage

packages/webpack-cli/src/webpack-cli.ts:724–810

(
    packageName: string,
    options: { preMessage?: () => void } = {},
  )

  }

  async installPackage(
    packageName: string,
    options: { preMessage?: () => void } = {},
  ): Promise<string> {
    const packageManager = await this.getDefaultPackageManager();

    if (!packageManager) {
      this.logger.error("Can't find package manager");

      process.exit(2);
    }

    if (options.preMessage) {
      options.preMessage();
    }

    const { createInterface } = await import("node:readline");

    const prompt = ({
      message,
      defaultResponse,
      stream,
    }: {
      message: string;
      defaultResponse: string;
      stream: NodeJS.WritableStream;
    }) => {
      const rl = createInterface({
        input: process.stdin,
        output: stream,
      });

      return new Promise((resolve) => {
        rl.question(`${message} `, (answer: string) => {
          // Close the stream
          rl.close();

          const response = (answer || defaultResponse).toLowerCase();

          // Resolve with the input response
          if (response === "y" || response === "yes") {
            resolve(true);
          } else {
            resolve(false);
          }
        });
      });
    };

    // yarn uses 'add' command, rest npm and pnpm both use 'install'
    const commandArguments = [packageManager === "yarn" ? "add" : "install", "-D", packageName];
    const commandToBeRun = `${packageManager} ${commandArguments.join(" ")}`;

    let needInstall;

    try {
      needInstall = await prompt({
        message: `[webpack-cli] Would you like to install '${this.colors.green(