use common linting configuration (sveltejs#4942)

Author: antony

.eslintignore

@@ -2,7 +2,6 @@
 **/expected.js
 _output
 test/*/samples/*/output.js
-node_modules
 
 # automatically generated
 internal_exports.ts

.eslintrc.js

@@ -1,65 +1,6 @@
 module.exports = {
 	root: true,
-	rules: {
-		indent: 'off',
-		'no-unused-vars': 'off',
-		semi: [2, 'always'],
-		'keyword-spacing': [2, { before: true, after: true }],
-		'space-before-blocks': [2, 'always'],
-		'no-mixed-spaces-and-tabs': [2, 'smart-tabs'],
-		'no-cond-assign': 0,
-		'object-shorthand': [2, 'always'],
-		'no-const-assign': 2,
-		'no-class-assign': 2,
-		'no-this-before-super': 2,
-		'no-var': 2,
-		'no-unreachable': 2,
-		'valid-typeof': 2,
-		'quote-props': [2, 'as-needed'],
-		'one-var': [2, 'never'],
-		'prefer-arrow-callback': 2,
-		'prefer-const': [2, { destructuring: 'all' }],
-		'arrow-spacing': 2,
-		'no-inner-declarations': 0,
-		'require-atomic-updates': 'off',
-		'@typescript-eslint/indent': 'off',
-		'@typescript-eslint/camelcase': 'off',
-		'@typescript-eslint/no-use-before-define': 'off',
-		'@typescript-eslint/array-type': ['error', 'array-simple'],
-		'@typescript-eslint/explicit-function-return-type': 'off',
-		'@typescript-eslint/no-explicit-any': 'off',
-		'@typescript-eslint/explicit-member-accessibility': 'off',
-		'@typescript-eslint/no-unused-vars': [
-			'error',
-			{
-				argsIgnorePattern: '^_'
-			}
-		],
-		'@typescript-eslint/no-object-literal-type-assertion': 'off',
-		'@typescript-eslint/no-unused-vars': 'off',
-		'@typescript-eslint/prefer-interface': 'off'
-	},
-	globals: {
-		globalThis: false
-	},
-	env: {
-		es6: true,
-		browser: true,
-		node: true,
-		mocha: true
-	},
-	extends: [
-		'eslint:recommended',
-		'plugin:import/errors',
-		'plugin:import/warnings',
-		'plugin:import/typescript',
-		'plugin:@typescript-eslint/recommended'
-	],
-	parserOptions: {
-		ecmaVersion: 9,
-		sourceType: 'module'
-	},
-	plugins: ['svelte3'],
+	extends: '@sveltejs',
 	settings: {
 		'import/core-modules': [
 			'svelte',
@@ -69,20 +10,5 @@ module.exports = {
 			'estree'
 		],
 		'svelte3/compiler': require('./compiler')
-	},
-	overrides: [
-		{
-			files: ['*.js'],
-			rules: {
-				'@typescript-eslint/no-var-requires': 'off'
-			}
-		},
-		{
-			files: ['*.svelte'],
-			processor: 'svelte3/svelte3',
-			rules: {
-				'@typescript-eslint/indent': 'off'
-			}
-		}
-	]
+	}
 };