`vue add unit-mocha` removes final newline from tsconfig.json

[spenserblack]

Version

4.5.7

Environment info

  System:
    OS: Linux 5.4 Ubuntu 20.04.1 LTS (Focal Fossa)
    CPU: (2) x64 Intel(R) Xeon(R) CPU E5-1603 v3 @ 2.80GHz
  Binaries:
    Node: 14.7.0 - ~/.nvm/versions/node/v14.7.0/bin/node
    Yarn: 1.22.10 - ~/.nvm/versions/node/v14.7.0/bin/yarn
    npm: 6.14.8 - ~/.nvm/versions/node/v14.7.0/bin/npm
  Browsers:
    Chrome: Not Found
    Firefox: 81.0
  npmPackages:
    @vue/babel-helper-vue-jsx-merge-props:  1.0.0 
    @vue/babel-helper-vue-transform-on:  1.0.0-rc.2 
    @vue/babel-plugin-jsx:  1.0.0-rc.3 
    @vue/babel-plugin-transform-vue-jsx:  1.1.2 
    @vue/babel-preset-app:  4.5.7 
    @vue/babel-preset-jsx:  1.1.2 
    @vue/babel-sugar-functional-vue:  1.1.2 
    @vue/babel-sugar-inject-h:  1.1.2 
    @vue/babel-sugar-v-model:  1.1.2 
    @vue/babel-sugar-v-on:  1.1.2 
    @vue/cli-overlay:  4.5.7 
    @vue/cli-plugin-babel: ~4.5.0 => 4.5.7 
    @vue/cli-plugin-eslint: ~4.5.0 => 4.5.7 
    @vue/cli-plugin-router:  4.5.7 
    @vue/cli-plugin-typescript: ~4.5.0 => 4.5.7 
    @vue/cli-plugin-unit-mocha: ~4.5.0 => 4.5.7 
    @vue/cli-plugin-vuex:  4.5.7 
    @vue/cli-service: ~4.5.0 => 4.5.7 
    @vue/cli-shared-utils:  4.5.7 
    @vue/component-compiler-utils:  3.2.0 
    @vue/eslint-config-typescript: ^5.0.2 => 5.1.0 
    @vue/preload-webpack-plugin:  1.1.2 
    @vue/test-utils: ^1.0.3 => 1.1.0 
    @vue/web-component-wrapper:  1.2.0 
    eslint-plugin-vue: ^7.0.1 => 7.0.1 
    typescript: ~4.0.3 => 4.0.3 
    vue: ^2.6.11 => 2.6.12 
    vue-eslint-parser:  7.1.0 
    vue-hot-reload-api:  2.3.4 
    vue-loader:  15.9.3 (16.0.0-beta.8)
    vue-style-loader:  4.1.2 
    vue-template-compiler: ^2.6.11 => 2.6.12 
    vue-template-es2015-compiler:  1.9.1 
  npmGlobalPackages:
    @vue/cli: 4.5.6

Steps to reproduce

vue create -i '{ "useConfigFiles": true, "plugins": { "@vue/cli-plugin-typescript": { "classComponent": false } }, "vueVersion": "2" }' sample-project
cd sample-project
vue add unit-mocha

What is expected?

The final newline remains unchanged

What is actually happening?

The final newline is removed, resulting in a diff like

@@ -12,7 +12,9 @@
     "sourceMap": true,
     "baseUrl": ".",
     "types": [
-      "webpack-env"
+      "webpack-env",
+      "mocha",
+      "chai"
     ],
     "paths": {
       "@/*": [
@@ -36,4 +38,4 @@
   "exclude": [
     "node_modules"
   ]
-}
+}
\ No newline at end of file

---

This is a very minor issue, so should probably be made low priority