const semver = require('semver'); const eslintPkg = require('eslint/package.json'); module.exports = { rules: { // enforce line breaks after opening and before closing array brackets // https://eslint.org/docs/rules/array-bracket-newline // TODO: enable? semver-major 'array-bracket-newline': ['off', 'consistent'], // object option alternative: { multiline: true, minItems: 3 } // enforce line breaks between array elements // https://eslint.org/docs/rules/array-element-newline // TODO: enable? semver-major 'array-element-newline': ['off', { multiline: true, minItems: 3 }], // enforce spacing inside array brackets 'array-bracket-spacing': ['error', 'never'], // enforce spacing inside single-line blocks // https://eslint.org/docs/rules/block-spacing 'block-spacing': ['error', 'always'], // enforce one true brace style 'brace-style': ['error', '1tbs', { allowSingleLine: true }], // require camel case names camelcase: ['error', { properties: 'never', ignoreDestructuring: false }], // enforce or disallow capitalization of the first letter of a comment // https://eslint.org/docs/rules/capitalized-comments 'capitalized-comments': ['off', 'never', { line: { ignorePattern: '.*', ignoreInlineComments: true, ignoreConsecutiveComments: true, }, block: { ignorePattern: '.*', ignoreInlineComments: true, ignoreConsecutiveComments: true, }, }], // require trailing commas in multiline object literals 'comma-dangle': ['error', { arrays: 'always-multiline', objects: 'always-multiline', imports: 'always-multiline', exports: 'always-multiline', functions: 'always-multiline', }], // enforce spacing before and after comma 'comma-spacing': ['error', { before: false, after: true }], // enforce one true comma style 'comma-style': ['error', 'last', { exceptions: { ArrayExpression: false, ArrayPattern: false, ArrowFunctionExpression: false, CallExpression: false, FunctionDeclaration: false, FunctionExpression: false, ImportDeclaration: false, ObjectExpression: false, ObjectPattern: false, VariableDeclaration: false, NewExpression: false, } }], // disallow padding inside computed properties 'computed-property-spacing': ['error', 'never'], // enforces consistent naming when capturing the current execution context 'consistent-this': 'off', // enforce newline at the end of file, with no multiple empty lines 'eol-last': ['error', 'always'], // https://eslint.org/docs/rules/function-call-argument-newline 'function-call-argument-newline': ['error', 'consistent'], // enforce spacing between functions and their invocations // https://eslint.org/docs/rules/func-call-spacing 'func-call-spacing': ['error', 'never'], // requires function names to match the name of the variable or property to which they are // assigned // https://eslint.org/docs/rules/func-name-matching 'func-name-matching': ['off', 'always', { includeCommonJSModuleExports: false, considerPropertyDescriptor: true, }], // require function expressions to have a name // https://eslint.org/docs/rules/func-names 'func-names': 'warn', // enforces use of function declarations or expressions // https://eslint.org/docs/rules/func-style // TODO: enable 'func-style': ['off', 'expression'], // require line breaks inside function parentheses if there are line breaks between parameters // https://eslint.org/docs/rules/function-paren-newline 'function-paren-newline': ['error', semver.satisfies(eslintPkg.version, '>= 6') ? 'multiline-arguments' : 'consistent'], // disallow specified identifiers // https://eslint.org/docs/rules/id-denylist 'id-denylist': 'off', // this option enforces minimum and maximum identifier lengths // (variable names, property names etc.) 'id-length': 'off', // require identifiers to match the provided regular expression 'id-match': 'off', // Enforce the location of arrow function bodies with implicit returns // https://eslint.org/docs/rules/implicit-arrow-linebreak 'implicit-arrow-linebreak': ['error', 'beside'], // this option sets a specific tab width for your code // https://eslint.org/docs/rules/indent indent: ['error', 2, { SwitchCase: 1, VariableDeclarator: 1, outerIIFEBody: 1, // MemberExpression: null, FunctionDeclaration: { parameters: 1, body: 1 }, FunctionExpression: { parameters: 1, body: 1 }, CallExpression: { arguments: 1 }, ArrayExpression: 1, ObjectExpression: 1, ImportDeclaration: 1, flatTernaryExpressions: false, // list derived from https://github.com/benjamn/ast-types/blob/HEAD/def/jsx.js ignoredNodes: ['JSXElement', 'JSXElement > *', 'JSXAttribute', 'JSXIdentifier', 'JSXNamespacedName', 'JSXMemberExpression', 'JSXSpreadAttribute', 'JSXExpressionContainer', 'JSXOpeningElement', 'JSXClosingElement', 'JSXFragment', 'JSXOpeningFragment', 'JSXClosingFragment', 'JSXText', 'JSXEmptyExpression', 'JSXSpreadChild'], ignoreComments: false }], // specify whether double or single quotes should be used in JSX attributes // https://eslint.org/docs/rules/jsx-quotes 'jsx-quotes': ['off', 'prefer-double'], // enforces spacing between keys and values in object literal properties 'key-spacing': ['error', { beforeColon: false, afterColon: true }], // require a space before & after certain keywords 'keyword-spacing': ['error', { before: true, after: true, overrides: { return: { after: true }, throw: { after: true }, case: { after: true } } }], // enforce position of line comments // https://eslint.org/docs/rules/line-comment-position // TODO: enable? 'line-comment-position': ['off', { position: 'above', ignorePattern: '', applyDefaultPatterns: true, }], // disallow mixed 'LF' and 'CRLF' as linebreaks // https://eslint.org/docs/rules/linebreak-style 'linebreak-style': ['error', 'unix'], // require or disallow an empty line between class members // https://eslint.org/docs/rules/lines-between-class-members 'lines-between-class-members': ['error', 'always', { exceptAfterSingleLine: false }], // enforces empty lines around comments 'lines-around-comment': 'off', // require or disallow newlines around directives // https://eslint.org/docs/rules/lines-around-directive 'lines-around-directive': ['error', { before: 'always', after: 'always', }], // specify the maximum depth that blocks can be nested 'max-depth': ['off', 4], // specify the maximum length of a line in your program // https://eslint.org/docs/rules/max-len 'max-len': ['error', 100, 2, { ignoreUrls: true, ignoreComments: false, ignoreRegExpLiterals: true, ignoreStrings: true, ignoreTemplateLiterals: true, }], // specify the max number of lines in a file // https://eslint.org/docs/rules/max-lines 'max-lines': ['off', { max: 300, skipBlankLines: true, skipComments: true }], // enforce a maximum function length // https://eslint.org/docs/rules/max-lines-per-function 'max-lines-per-function': ['off', { max: 50, skipBlankLines: true, skipComments: true, IIFEs: true, }], // specify the maximum depth callbacks can be nested 'max-nested-callbacks': 'off', // limits the number of parameters that can be used in the function declaration. 'max-params': ['off', 3], // specify the maximum number of statement allowed in a function 'max-statements': ['off', 10], // restrict the number of statements per line // https://eslint.org/docs/rules/max-statements-per-line 'max-statements-per-line': ['off', { max: 1 }], // enforce a particular style for multiline comments // https://eslint.org/docs/rules/multiline-comment-style 'multiline-comment-style': ['off', 'starred-block'], // require multiline ternary // https://eslint.org/docs/rules/multiline-ternary // TODO: enable? 'multiline-ternary': ['off', 'never'], // require a capital letter for constructors 'new-cap': ['error', { newIsCap: true, newIsCapExceptions: [], capIsNew: false, capIsNewExceptions: ['Immutable.Map', 'Immutable.Set', 'Immutable.List'], }], // disallow the omission of parentheses when invoking a constructor with no arguments // https://eslint.org/docs/rules/new-parens 'new-parens': 'error', // allow/disallow an empty newline after var statement 'newline-after-var': 'off', // https://eslint.org/docs/rules/newline-before-return 'newline-before-return': 'off', // enforces new line after each method call in the chain to make it // more readable and easy to maintain // https://eslint.org/docs/rules/newline-per-chained-call 'newline-per-chained-call': ['error', { ignoreChainWithDepth: 4 }], // disallow use of the Array constructor 'no-array-constructor': 'error', // disallow use of bitwise operators // https://eslint.org/docs/rules/no-bitwise 'no-bitwise': 'error', // disallow use of the continue statement // https://eslint.org/docs/rules/no-continue 'no-continue': 'error', // disallow comments inline after code 'no-inline-comments': 'off', // disallow if as the only statement in an else block // https://eslint.org/docs/rules/no-lonely-if 'no-lonely-if': 'error', // disallow un-paren'd mixes of different operators // https://eslint.org/docs/rules/no-mixed-operators 'no-mixed-operators': ['error', { // the list of arithmetic groups disallows mixing `%` and `**` // with other arithmetic operators. groups: [ ['%', '**'], ['%', '+'], ['%', '-'], ['%', '*'], ['%', '/'], ['/', '*'], ['&', '|', '<<', '>>', '>>>'], ['==', '!=', '===', '!=='], ['&&', '||'], ], allowSamePrecedence: false }], // disallow mixed spaces and tabs for indentation 'no-mixed-spaces-and-tabs': 'error', // disallow use of chained assignment expressions // https://eslint.org/docs/rules/no-multi-assign 'no-multi-assign': ['error'], // disallow multiple empty lines, only one newline at the end, and no new lines at the beginning // https://eslint.org/docs/rules/no-multiple-empty-lines 'no-multiple-empty-lines': ['error', { max: 1, maxBOF: 0, maxEOF: 0 }], // disallow negated conditions // https://eslint.org/docs/rules/no-negated-condition 'no-negated-condition': 'off', // disallow nested ternary expressions 'no-nested-ternary': 'error', // disallow use of the Object constructor 'no-new-object': 'error', // disallow use of unary operators, ++ and -- // https://eslint.org/docs/rules/no-plusplus 'no-plusplus': 'error', // disallow certain syntax forms // https://eslint.org/docs/rules/no-restricted-syntax 'no-restricted-syntax': [ 'error', { selector: 'ForInStatement', message: 'for..in loops iterate over the entire prototype chain, which is virtually never what you want. Use Object.{keys,values,entries}, and iterate over the resulting array.', }, { selector: 'ForOfStatement', message: 'iterators/generators require regenerator-runtime, which is too heavyweight for this guide to allow them. Separately, loops should be avoided in favor of array iterations.', }, { selector: 'LabeledStatement', message: 'Labels are a form of GOTO; using them makes code confusing and hard to maintain and understand.', }, { selector: 'WithStatement', message: '`with` is disallowed in strict mode because it makes code impossible to predict and optimize.', }, ], // disallow space between function identifier and application 'no-spaced-func': 'error', // disallow tab characters entirely 'no-tabs': 'error', // disallow the use of ternary operators 'no-ternary': 'off', // disallow trailing whitespace at the end of lines 'no-trailing-spaces': ['error', { skipBlankLines: false, ignoreComments: false, }], // disallow dangling underscores in identifiers // https://eslint.org/docs/rules/no-underscore-dangle 'no-underscore-dangle': ['error', { allow: [], allowAfterThis: false, allowAfterSuper: false, enforceInMethodNames: true, }], // disallow the use of Boolean literals in conditional expressions // also, prefer `a || b` over `a ? a : b` // https://eslint.org/docs/rules/no-unneeded-ternary 'no-unneeded-ternary': ['error', { defaultAssignment: false }], // disallow whitespace before properties // https://eslint.org/docs/rules/no-whitespace-before-property 'no-whitespace-before-property': 'error', // enforce the location of single-line statements // https://eslint.org/docs/rules/nonblock-statement-body-position 'nonblock-statement-body-position': ['error', 'beside', { overrides: {} }], // require padding inside curly braces 'object-curly-spacing': ['error', 'always'], // enforce line breaks between braces // https://eslint.org/docs/rules/object-curly-newline 'object-curly-newline': ['error', { ObjectExpression: { minProperties: 4, multiline: true, consistent: true }, ObjectPattern: { minProperties: 4, multiline: true, consistent: true }, ImportDeclaration: { minProperties: 4, multiline: true, consistent: true }, ExportDeclaration: { minProperties: 4, multiline: true, consistent: true }, }], // enforce "same line" or "multiple line" on object properties. // https://eslint.org/docs/rules/object-property-newline 'object-property-newline': ['error', { allowAllPropertiesOnSameLine: true, }], // allow just one var statement per function 'one-var': ['error', 'never'], // require a newline around variable declaration // https://eslint.org/docs/rules/one-var-declaration-per-line 'one-var-declaration-per-line': ['error', 'always'], // require assignment operator shorthand where possible or prohibit it entirely // https://eslint.org/docs/rules/operator-assignment 'operator-assignment': ['error', 'always'], // Requires operator at the beginning of the line in multiline statements // https://eslint.org/docs/rules/operator-linebreak 'operator-linebreak': ['error', 'before', { overrides: { '=': 'none' } }], // disallow padding within blocks 'padded-blocks': ['error', { blocks: 'never', classes: 'never', switches: 'never', }, { allowSingleLineBlocks: true, }], // Require or disallow padding lines between statements // https://eslint.org/docs/rules/padding-line-between-statements 'padding-line-between-statements': 'off', // Disallow the use of Math.pow in favor of the ** operator // https://eslint.org/docs/rules/prefer-exponentiation-operator 'prefer-exponentiation-operator': 'error', // Prefer use of an object spread over Object.assign // https://eslint.org/docs/rules/prefer-object-spread 'prefer-object-spread': 'error', // require quotes around object literal property names // https://eslint.org/docs/rules/quote-props.html 'quote-props': ['error', 'as-needed', { keywords: false, unnecessary: true, numbers: false }], // specify whether double or single quotes should be used quotes: ['error', 'single', { avoidEscape: true }], // do not require jsdoc // https://eslint.org/docs/rules/require-jsdoc 'require-jsdoc': 'off', // require or disallow use of semicolons instead of ASI semi: ['error', 'always'], // enforce spacing before and after semicolons 'semi-spacing': ['error', { before: false, after: true }], // Enforce location of semicolons // https://eslint.org/docs/rules/semi-style 'semi-style': ['error', 'last'], // requires object keys to be sorted 'sort-keys': ['off', 'asc', { caseSensitive: false, natural: true }], // sort variables within the same declaration block 'sort-vars': 'off', // require or disallow space before blocks 'space-before-blocks': 'error', // require or disallow space before function opening parenthesis // https://eslint.org/docs/rules/space-before-function-paren 'space-before-function-paren': ['error', { anonymous: 'always', named: 'never', asyncArrow: 'always' }], // require or disallow spaces inside parentheses 'space-in-parens': ['error', 'never'], // require spaces around operators 'space-infix-ops': 'error', // Require or disallow spaces before/after unary operators // https://eslint.org/docs/rules/space-unary-ops 'space-unary-ops': ['error', { words: true, nonwords: false, overrides: { }, }], // require or disallow a space immediately following the // or /* in a comment // https://eslint.org/docs/rules/spaced-comment 'spaced-comment': ['error', 'always', { line: { exceptions: ['-', '+'], markers: ['=', '!', '/'], // space here to support sprockets directives, slash for TS /// comments }, block: { exceptions: ['-', '+'], markers: ['=', '!', ':', '::'], // space here to support sprockets directives and flow comment types balanced: true, } }], // Enforce spacing around colons of switch statements // https://eslint.org/docs/rules/switch-colon-spacing 'switch-colon-spacing': ['error', { after: true, before: false }], // Require or disallow spacing between template tags and their literals // https://eslint.org/docs/rules/template-tag-spacing 'template-tag-spacing': ['error', 'never'], // require or disallow the Unicode Byte Order Mark // https://eslint.org/docs/rules/unicode-bom 'unicode-bom': ['error', 'never'], // require regex literals to be wrapped in parentheses 'wrap-regex': 'off' } };