webpack不是创建bundle.js文件吗？

Question

我创建了简单的react应用和webpack进行捆绑，这是

webpack.config.js

module.exports = {
  entr:{
    app:'./src/index.js'
  },
  output: {
    path: path.join('./dist'),
    filename: 'bundle.js'
  },
  module: {
    rules: [
      {
        test: /\.(js|jsx)$/,
        exclude: /node_modules/,
        use: {
          loader: "babel-loader"
        }
      }
    ]
  }
};

package.json

{
  "name": "webpack-js",
  "version": "1.0.0",
  "description": "",
  "main": "index.js",
  "dependencies": {
    "babel": "^6.23.0",
    "babel-core": "^6.26.3",
    "babel-generator": "^6.26.1",
    "babel-helper-replace-supers": "^6.24.1",
    "babel-helpers": "^6.24.1",
    "babel-preset-react": "^6.24.1",
    "babel-register": "^6.26.0",
    "bable-loader": "^0.0.1-security",
    "convert-source-map": "^1.6.0",
    "json5": "^0.5.1",
    "react": "^0.14.9",
    "react-dom": "^0.14.9",
    "regenerator-transform": "^0.10.1",
    "slash": "^1.0.0",
    "trim-right": "^1.0.1"
  },
  "devDependencies": {
    "@babel/core": "^7.4.5",
    "@babel/preset-env": "^7.4.5",
    "@babel/preset-react": "^7.0.0",
    "babel-loader": "^8.0.6",
    "prop-types": "^15.7.2",
    "webpack": "^1.15.0",
    "webpack-cli": "^3.3.2"
  },
  "scripts": {
    "test": "echo \"Error: no test specified\" && exit 1",
    "build": "webpack --mode production"
  },
  "keywords": [],
  "author": "",
  "license": "ISC"
}

运行npm run build命令后，它会在cmd上提示以下消息，但没有bundle.js文件。

E:\Dev\webpack-js>npm run build

> webpack-js@1.0.0 build E:\Dev\webpack-js
> webpack --mode production

Hash: 396f0bfb9d565b6f60f0
Version: webpack 1.15.0
Time: 46ms

为什么不创建bundle.js文件？