Add eslint and prettier + fix pytest error (#78)

* add eslint and prettier

* add eslintrc

* get eslint working

interface-name-prefix has been removed from recommended so it was causing errors. I also fixed a few mistakes I made

* run lint

* fixing py.test error

Author: ianhi

.travis.yml

@@ -27,6 +27,7 @@ before_script:
 script:
   - py.test
   - npm test
+  - npm run lint:check
   # Check docs can be build + links
   - pushd docs
   - make html

{{cookiecutter.github_project_name}}/.eslintignore

@@ -0,0 +1,5 @@
+node_modules
+dist
+coverage
+**/*.d.ts
+tests

{{cookiecutter.github_project_name}}/.eslintrc.js

@@ -0,0 +1,28 @@
+module.exports = {
+  extends: [
+    'eslint:recommended',
+    'plugin:@typescript-eslint/eslint-recommended',
+    'plugin:@typescript-eslint/recommended',
+    'plugin:prettier/recommended'
+  ],
+  parser: '@typescript-eslint/parser',
+  parserOptions: {
+    project: 'tsconfig.json',
+    sourceType: 'module'
+  },
+  plugins: ['@typescript-eslint'],
+  rules: {
+    '@typescript-eslint/no-unused-vars': ['warn', { args: 'none' }],
+    '@typescript-eslint/no-explicit-any': 'off',
+    '@typescript-eslint/no-namespace': 'off',
+    '@typescript-eslint/no-use-before-define': 'off',
+    '@typescript-eslint/quotes': [
+      'error',
+      'single',
+      { avoidEscape: true, allowTemplateLiterals: false }
+    ],
+    curly: ['error', 'all'],
+    eqeqeq: 'error',
+    'prefer-arrow-callback': 'error'
+  }
+};

{{cookiecutter.github_project_name}}/.prettierignore

@@ -0,0 +1,4 @@
+node_modules
+**/node_modules
+**/lib
+**/package.json

{{cookiecutter.github_project_name}}/.prettierrc

@@ -0,0 +1,3 @@
+{
+    "singleQuote": true
+}

{{cookiecutter.github_project_name}}/package.json

@@ -38,6 +38,8 @@
     "clean:lib": "rimraf lib",
     "clean:labextension": "rimraf {{ cookiecutter.python_package_name }}/labextension",
     "clean:nbextension": "rimraf {{ cookiecutter.python_package_name }}/nbextension/static/index.js",
+    "lint": "eslint . --ext .ts,.tsx --fix",
+    "lint:check": "eslint . --ext .ts,.tsx",
     "prepack": "npm run build:lib",
     "test": "npm run test:firefox",
     "test:chrome": "karma start --browsers=Chrome tests/karma.conf.js",
@@ -58,8 +60,13 @@
     "@types/mocha": "^5.2.5",
     "@types/node": "^10.11.6",
     "@types/webpack-env": "^1.13.6",
+    "@typescript-eslint/eslint-plugin": "^3.6.0",
+    "@typescript-eslint/parser": "^3.6.0",
     "acorn": "^7.2.0",
     "css-loader": "^3.2.0",
+    "eslint": "^7.4.0",
+    "eslint-config-prettier": "^6.11.0",
+    "eslint-plugin-prettier": "^3.1.4",
     "expect.js": "^0.3.1",
     "fs-extra": "^7.0.0",
     "karma": "^3.1.0",
@@ -73,6 +80,7 @@
     "mkdirp": "^0.5.1",
     "mocha": "^5.2.0",
     "npm-run-all": "^4.1.3",
+    "prettier": "^2.0.5",
     "rimraf": "^2.6.2",
     "source-map-loader": "^0.2.4",
     "style-loader": "^1.0.0",

{{cookiecutter.github_project_name}}/setup.py

@@ -90,7 +90,7 @@
     ],
     extras_require = {
         'test': [
-            'pytest>=3.6',
+            'pytest>=4.6',
             'pytest-cov',
             'nbval',
         ],

{{cookiecutter.github_project_name}}/src/extension.ts

@@ -8,6 +8,9 @@
 // Some static assets may be required by the custom widget javascript. The base
 // url for the notebook is not known at build time and is therefore computed
 // dynamically.
-(window as any).__webpack_public_path__ = document.querySelector('body')!.getAttribute('data-base-url') + 'nbextensions/{{ cookiecutter.python_package_name }}';
+// eslint-disable-next-line @typescript-eslint/no-non-null-assertion
+(window as any).__webpack_public_path__ =
+  document.querySelector('body')!.getAttribute('data-base-url') +
+  'nbextensions/{{ cookiecutter.python_package_name }}';
 
 export * from './index';

{{cookiecutter.github_project_name}}/src/plugin.ts

@@ -1,45 +1,39 @@
 // Copyright (c) {{ cookiecutter.author_name }}
 // Distributed under the terms of the Modified BSD License.
 
-import {
-  Application, IPlugin
-} from '@phosphor/application';
+import { Application, IPlugin } from '@phosphor/application';
 
-import {
-  Widget
-} from '@phosphor/widgets';
+import { Widget } from '@phosphor/widgets';
 
-import {
-  IJupyterWidgetRegistry
- } from '@jupyter-widgets/base';
+import { IJupyterWidgetRegistry } from '@jupyter-widgets/base';
 
 import * as widgetExports from './widget';
 
-import {
-  MODULE_NAME, MODULE_VERSION
-} from './version';
+import { MODULE_NAME, MODULE_VERSION } from './version';
 
 const EXTENSION_ID = '{{ cookiecutter.npm_package_name }}:plugin';
 
 /**
  * The example plugin.
  */
-const examplePlugin: IPlugin<Application<Widget>, void> = {
+const examplePlugin: IPlugin<Application<Widget>, void> = ({
   id: EXTENSION_ID,
   requires: [IJupyterWidgetRegistry],
   activate: activateWidgetExtension,
-  autoStart: true
-} as unknown as IPlugin<Application<Widget>, void>;
+  autoStart: true,
+} as unknown) as IPlugin<Application<Widget>, void>;
 // the "as unknown as ..." typecast above is solely to support JupyterLab 1
 // and 2 in the same codebase and should be removed when we migrate to Lumino.
 
 export default examplePlugin;
 
-
 /**
  * Activate the widget extension.
  */
-function activateWidgetExtension(app: Application<Widget>, registry: IJupyterWidgetRegistry): void {
+function activateWidgetExtension(
+  app: Application<Widget>,
+  registry: IJupyterWidgetRegistry
+): void {
   registry.registerWidget({
     name: MODULE_NAME,
     version: MODULE_VERSION,

{{cookiecutter.github_project_name}}/src/version.ts

@@ -1,6 +1,7 @@
 // Copyright (c) {{ cookiecutter.author_name }}
 // Distributed under the terms of the Modified BSD License.
 
+// eslint-disable-next-line @typescript-eslint/no-var-requires
 const data = require('../package.json');
 
 /**