Add eslint rules

.eslintrc.js

@@ -22,24 +22,110 @@ module.exports = {
     'sourceType': 'module'
   },
   'plugins': [
+    'simple-import-sort',
     'react'
   ],
   'ignorePatterns': ['**/static/**/*.js'],
   'rules': {
-    'indent': 'off',
+    // Disable unused rules
     'no-empty-pattern': 'off',
-    'linebreak-style': [
+
+    // Unix linebreaks only
+    'linebreak-style': ['error', 'unix'],
+
+    // Single quotes, allow double to avoid escaping
+    'quotes': [
       'error',
-      'unix'
+      'single',
+      { 'avoidEscape': true }
     ],
-    'quotes': [
+
+    // No semicolons
+    'semi': ['error', 'never'],
+
+    // Maximum line length of 120 characters
+    'max-len': [
+      'error',
+      {
+        'code': 120,
+        'ignoreUrls': true,
+        'ignoreRegExpLiterals': true
+      }
+    ],
+
+    // Indent by 2 spaces
+    'indent': ['error', 2, {
+      'SwitchCase': 1,
+    }],
+
+    // Import order
+    'simple-import-sort/imports': ['error', {
+      groups: [
+        // external imports in the given order
+        ['^react$', '^prop-types$', '^react', '^[a-z]', '^lodash'],
+        // rdmo imports: lowercase first, then capitalized components
+        ['^rdmo/.*\\/[a-z]'],
+        ['^rdmo/.*\\/[A-Z]'],
+        // parent imports: lowercase first, then capitalized components
+        ['^\\.\\..*\\/[a-z]'],
+        ['^\\.\\..*\\/[A-Z]'],
+        // sibling imports: lowercase first, then capitalized  components
+        ['^\\./.*\\/[a-z]'],
+        ['^\\./.*\\/[A-Z]'],
+      ],
+    }],
+
+    // Export order
+    'simple-import-sort/exports': 'error',
+
+    // Disallow newlines between the operands of a ternary expression
+    'multiline-ternary': ['error', 'never'],
+
+    // Ensure spaces after commas
+    'comma-spacing': ['error', { before: false, after: true }],
+
+    // Ensure correct multiline imports
+    'object-curly-newline': ['error', {
+      ImportDeclaration: {
+        multiline: true,
+        consistent: true
+      }
+    }],
+
+    // JSX: wrap multiline expressions in parens, opening paren on a new line
+    'react/jsx-wrap-multilines': [
       'error',
-      'single'
+      {
+        'declaration': 'parens-new-line',
+        'assignment': 'parens-new-line',
+        'return': 'parens-new-line',
+        'arrow': 'parens-new-line',
+        'condition': 'parens-new-line',
+        'logical': 'parens-new-line',
+        'prop': 'parens-new-line'
+      }
     ],
-    'semi': [
+
+    // JSX curly braces: require newlines inside for multiline expressions
+    'react/jsx-curly-newline': [
       'error',
-      'never'
-    ]
+      {
+        'multiline': 'require',
+        'singleline': 'consistent'
+      }
+    ],
+
+    // JSX curly brace spacing: no spaces inside { }
+    'react/jsx-curly-spacing': [
+      'error',
+      {
+        'when': 'never',
+        'children': true
+      }
+    ],
+
+    // JSX double quotes for props
+    'jsx-quotes': ['error', 'prefer-double'],
   },
   'settings': {
     'react': {

package.json

@@ -56,6 +56,7 @@
     "css-loader": "^7.1.1",
     "eslint": "~8.56.0",
     "eslint-plugin-react": "^7.37.2",
+    "eslint-plugin-simple-import-sort": "^12.1.1",
     "file-loader": "^6.2.0",
     "mini-css-extract-plugin": "^2.9.0",
     "sass": "^1.94.2",