Eslint: brace-style: Having a catch method on a plain ES6 class throws `Closing curly brace does not appear on the same line as the subsequent brace style`

[kojinkai]

Tell us about your environment

• ESLint Version: 3.14.0
• Node Version: 4.4.7
• npm Version: 2.15.8

What parser (default, Babel-ESLint, etc.) are you using?
babel-eslint v5.0.4
Please show your full configuration:

{
  // http://eslint.org/docs/rules/
  "parser": "babel-eslint",
  "ecmaFeatures": {
    "binaryLiterals": false,                    // enable binary literals
    "blockBindings": false,                     // enable let and const (aka block bindings)
    "defaultParams": false,                     // enable default function parameters
    "forOf": false,                             // enable for-of loops
    "generators": false,                        // enable generators
    "modules": true,                            // enable ES Module System
    "objectLiteralComputedProperties": false,   // enable computed object literal property names
    "objectLiteralDuplicateProperties": false,  // enable duplicate object literal properties in strict mode
    "objectLiteralShorthandMethods": false,     // enable object literal shorthand methods
    "objectLiteralShorthandProperties": false,  // enable object literal shorthand properties
    "octalLiterals": false,                     // enable octal literals
    "regexUFlag": false,                        // enable the regular expression u flag
    "regexYFlag": false,                        // enable the regular expression y flag
    "templateStrings": false,                   // enable template strings
    "unicodeCodePointEscapes": false,           // enable code point escapes
    "jsx": false                                // enable JSX
  },

  "env": {
    "es6": true,         // all es6 features except modules
    "browser": true,     // browser global variables.
    "node": true,        // Node.js global variables and Node.js-specific rules.
    "jasmine": true,     // adds all of the Jasmine testing global variables for version 1.3 and 2.0.
    "phantomjs": true,   // phantomjs global variables.
    "jquery": true,      // jquery global variables.
  },

  "globals": {
    "document": true,
    "angular": true,
    "$": true
  },

  "plugins": [
    // e.g. "react" (must run `npm install eslint-plugin-react` first)
  ],

  "rules": {
    ////////// Possible Errors ////////

    // http://eslint.org/docs/rules/ //

    // 0 = 'off', 1 = 'warn', 2 = 'error' //
    "indent": [2, 2],
    "comma-dangle": 2,            // disallow trailing commas in object literals
    "no-cond-assign": 1,          // disallow assignment in conditional expressions
    "no-console": 1,              // disallow use of console (off by default in the node environment)
    "no-constant-condition": 2,   // disallow use of constant expressions in conditions
    "no-control-regex": 0,    // disallow control characters in regular expressions
    "no-debugger": 2,             // disallow use of debugger
    "no-dupe-keys": 2,            // disallow duplicate keys when creating object literals
    "no-empty": 2,                // disallow empty statements
    "no-empty-character-class": 2,// disallow the use of empty character classes in regular expressions
    "no-ex-assign": 2,            // disallow assigning to the exception in a catch block
    "no-extra-boolean-cast": 1 ,  // disallow double-negation boolean casts in a boolean context
    "no-extra-parens": 1,         // disallow unnecessary parentheses (off by default)
    "no-extra-semi": 2,           // disallow unnecessary semicolons
    "no-func-assign": 2,          // disallow overwriting functions written as function declarations
    "no-inner-declarations": 2,   // disallow function or variable declarations in nested blocks
    "no-invalid-regexp": 2,       // disallow invalid regular expression strings in the RegExp constructor
    "no-irregular-whitespace": 2, // disallow irregular whitespace outside of strings and comments
    "no-negated-in-lhs": 2,       // disallow negation of the left operand of an in expression
    "no-obj-calls": 2,            // disallow the use of object properties of the global object (Math and JSON) as functions
    "no-regex-spaces": 1,         // disallow multiple spaces in a regular expression literal
    "no-sparse-arrays": 2,        // disallow sparse arrays
    "no-unreachable": 2,          // disallow unreachable statements after a return, throw, continue, or break statement
    "use-isnan": 2,               // disallow comparisons with the value NaN
    "valid-jsdoc": 1,             // Ensure JSDoc comments are valid (off by default)
    "valid-typeof": 2,            // Ensure that the results of typeof are compared against a valid string


    ////////// Best Practices //////////

    "block-scoped-var": 2,      // treat var statements as if they were block scoped (off by default)
    "complexity": [2, {
      "max": 3
    }],                         // specify the maximum cyclomatic complexity allowed in a program (off by default)
    "consistent-return": 0,     // require return statements to either always or never specify values
    "curly": 2,                 // specify curly brace conventions for all control statements
    "default-case": 2,          // require default case in switch statements (off by default)
    "dot-notation": 2,          // encourages use of dot notation whenever possible
    "eqeqeq": 2,                // require the use of === and !==
    "guard-for-in": 1,          // make sure for-in loops have an if statement (off by default)
    "no-alert": 2,              // disallow the use of alert, confirm, and prompt
    "no-caller": 2,             // disallow use of arguments.caller or arguments.callee
    "no-div-regex": 0,          // disallow division operators explicitly at beginning of regular expression (off by default)
    "no-else-return":2,         // disallow else after a return in an if (off by default)
    "no-labels": 2,             // disallow use of labels for anything other then loops and switches
    "no-eq-null": 2,            // disallow comparisons to null without a type-checking operator (off by default)
    "no-eval": 2,               // disallow use of eval()
    "no-extend-native": 2,      // disallow adding to native types
    "no-extra-bind": 2,         // disallow unnecessary function binding
    "no-fallthrough": 2,        // disallow fallthrough of case statements
    "no-floating-decimal": 2,   // disallow the use of leading or trailing decimal points in numeric literals (off by default)
    "no-implied-eval": 2,       // disallow use of eval()-like methods
    "no-iterator": 2,           // disallow usage of __iterator__ property
    "no-lone-blocks": 2,        // disallow unnecessary nested blocks
    "no-loop-func": 2,          // disallow creation of functions within loops
    "no-multi-spaces": 0,       // disallow use of multiple spaces
    "no-multi-str": 2,          // disallow use of multiline strings
    "no-native-reassign": 2,    // disallow reassignments of native objects
    "no-new": 2,                // disallow use of new operator when not part of the assignment or comparison
    "no-new-func": 2,           // disallow use of new operator for Function object
    "no-new-wrappers": 2,       // disallows creating new instances of String, Number, and Boolean
    "no-octal": 2,              // disallow use of octal literals
    "no-octal-escape": 1,       // disallow use of octal escape sequences in string literals, such as var foo = "Copyright \251";
    "no-process-env": 1,        // disallow use of process.env (off by default)
    "no-proto": 1,              // disallow usage of __proto__ property
    "no-redeclare":2,           // disallow declaring the same variable more then once
    "no-return-assign": 2,      // disallow use of assignment in return statement
    "no-self-assign": 2,        // disallow assignment operators in return statements
    "no-script-url": 2,         // disallow use of javascript: urls.
    "no-self-compare": 2,       // disallow comparisons where both sides are exactly the same (off by default)
    "no-sequences": 2,          // disallow use of comma operator
    "no-unused-expressions": 2, // disallow usage of expressions in statement position
    "no-void": 0,               // disallow use of void operator (off by default)
    "no-warning-comments": 0,   // disallow usage of configurable warning terms in comments, e.g. TODO or FIXME (off by default)
    "no-with": 0,               // disallow use of the with statement
    "radix": 2,                 // require use of the second argument for parseInt() (off by default)
    "vars-on-top": 2,           // requires to declare all vars on top of their containing scope (off by default)
    "wrap-iife": 0,             // require immediate function invocation to be wrapped in parentheses (off by default)
    "yoda": 1,                  // require or disallow Yoda conditions


    ////////// Strict Mode //////////

    "strict": 2,          // controls location of Use Strict Directives

    ////////// Variables //////////
    "init-declarations": 0,           // require or disallow initialization in var declarations
    "no-catch-shadow": 2,             // disallow the catch clause parameter name being the same as a variable in the outer scope (off by default in the node environment)
    "no-delete-var": 2,               // disallow deletion of variables
    "no-label-var": 2,                // disallow labels that share a name with a variable
    "no-shadow": 2,                   // disallow declaration of variables already declared in the outer scope
    "no-shadow-restricted-names": 2,  // disallow shadowing of names such as arguments
    "no-undef": 2,                    // disallow use of undeclared variables unless mentioned in a /*global */ block
    "no-undef-init": 2,               // disallow use of undefined when initializing variables
    "no-undefined": 2,                // disallow use of undefined variable (off by default)
    "no-unused-vars": 2,              // disallow declaration of variables that are not used in the code
    "no-use-before-define": 2,        // disallow use of variables before they are defined


    ////////// Node.js //////////

    "handle-callback-err": 0,   // enforces error handling in callbacks (off by default) (on by default in the node environment)
    "no-mixed-requires": 0,     // disallow mixing regular variable and require declarations (off by default) (on by default in the node environment)
    "no-new-require": 0,        // disallow use of new operator with the require function (off by default) (on by default in the node environment)
    "no-path-concat": 0,        // disallow string concatenation with __dirname and __filename (off by default) (on by default in the node environment)
    "no-process-exit": 0,       // disallow process.exit() (on by default in the node environment)
    "no-restricted-modules": 0, // restrict usage of specified node modules (off by default)
    "no-sync": 0,               // disallow use of synchronous methods (off by default)


    ////////// Stylistic Issues //////////

    "brace-style": [2, "1tbs"],       // enforce one true brace style (off by default)
    "camelcase": [2, {
      properties: "always"
    }],                                     // require camel case names
    "comma-spacing": [2, {
      "before": false,
      "after": true
    }],                                     // enforce spacing before and after comma
    "comma-style": [2, "last"],       // enforce one true comma style (off by default)
    "consistent-this": [2, "_this"],  // enforces consistent naming when capturing the current execution context (off by default)
    "eol-last": 2,                          // enforce newline at the end of file, with no multiple empty lines
    "func-names": 0,                        // require function expressions to have a name (off by default)
    "func-style": 0,                        // enforces use of function declarations or expressions (off by default)
    "key-spacing": [2, {
      "beforeColon": false,
      "afterColon": true
    }],                                     // enforces spacing between keys and values in object literal properties
    "max-nested-callbacks": [2, 3],   // specify the maximum depth callbacks can be nested (off by default)
    "new-cap": 2,                           // require a capital letter for constructors
    "new-parens": 2,                        // disallow the omission of parentheses when invoking a constructor with no arguments
    "no-array-constructor": 2,              // disallow use of the Array constructor
    "no-inline-comments": 0,                // disallow comments inline after code (off by default)
    "no-lonely-if": 2,                      // disallow if as the only statement in an else block (off by default)
    "no-mixed-spaces-and-tabs": 2,          // disallow mixed spaces and tabs for indentation
    "no-multiple-empty-lines": 2,           // disallow multiple empty lines (off by default)
    "no-nested-ternary": 1,                 // disallow nested ternary expressions (off by default)
    "no-new-object": 2,                     // disallow use of the Object constructor
    "semi-spacing": [2, {
      "before": false,
      "after": true
    }],                                     // disallow space before semicolon
    "no-spaced-func": 2,                    // disallow space between function identifier and application
    "no-ternary": 0,                        // disallow the use of ternary operators (off by default)
    "no-trailing-spaces": 2,                // disallow trailing whitespace at the end of lines
    "no-underscore-dangle": 0,              // disallow dangling underscores in identifiers
    "one-var": 0,                           // allow just one var statement per function (off by default)
    "operator-assignment": 0,               // require assignment operator shorthand where possible or prohibit it entirely (off by default)
    "padded-blocks": 0,                     // enforce padding within blocks (off by default)
    "quote-props": 0,                       // require quotes around object literal property names (off by default)
    "quotes": [2, "single"],          // specify whether double or single quotes should be used
    "semi": [2, "always"],            // require or disallow use of semicolons instead of ASI
    "sort-vars": 2,                         // sort variables within the same declaration block (off by default)
    "space-before-function-paren": [
      2, "never"
    ],                                      // require a space after function names (off by default)
    "keyword-spacing": 2,                   // require a space after certain keywords (off by default)
    "space-before-blocks": 2,               // require or disallow space before blocks (off by default)
    "object-curly-spacing": [
      2, "always"
    ],                                      // require or disallow spaces around object literals
    "array-bracket-spacing": [
      2, "never"
    ],                                      // require or disallow spacing around array brackets
    "space-in-parens": [
      2, "never"
    ],                                      // require or disallow spaces inside parentheses (off by default)
    "space-infix-ops": 2,                   // require spaces around operators
    "space-unary-ops": [
      2, {
        "words": true,
        "nonwords": false
      }
    ],                                      // Require or disallow spaces before/after unary operators (words on by default, nonwords off by default)
    "spaced-comment": 2,                    // require or disallow a space immediately following the // in a line comment (off by default)
    "wrap-regex": 0,                        // require regex literals to be wrapped in parentheses (off by default)


    ////////// ECMAScript 6 //////////

    "no-var": 2,          // require let or const instead of var (off by default)
    "generator-star": 0,  // enforce the position of the * in generator functions (off by default)


    ////////// Legacy //////////

    "max-depth": 0,       // specify the maximum depth that blocks can be nested (off by default)
    "max-len": 0,         // specify the maximum length of a line in your program (off by default)
    "max-params": 0,      // limits the number of parameters that can be used in the function declaration. (off by default)
    "max-statements": 0,  // specify the maximum number of statement allowed in a function (off by default)
    "no-bitwise": 0,      // disallow use of bitwise operators (off by default)
    "no-plusplus": 0      // disallow use of unary operators, ++ and -- (off by default)
  }
}

What did you do? Please include the actual source code causing the issue.
We are mocking a promise interface within a backing object for our unit tests as part of a fake HTTP backend implementation. It seems as though since v3.14.0 eslint thinks the catch method we have mocked here should always be a chained method call on a promise object.

export default class {

  constructor(data) {
    this.data = data;
  }

  then(callback) {
    this.data = callback(this.data);
    return this;
  }

  catch(callback) {
    callback({});
    return this;
  }
}

What did you expect to happen?
For eslint to recognise this as a plain ES6 class and lint it as such

What actually happened? Please include the actual, raw output from ESLint.

Package.json name and version, and paths obfuscated here

[10:55:00] Using gulpfile ~/path/to/project/root/gulpfile.js
[10:55:00] Starting 'eslint'...
[10:55:02] ~/path/to/project/root/app/js/tests/backing/promises/fake-promise.js
  15:3  error  Closing curly brace does not appear on the same line as the subsequent block  brace-style

✖ 1 problem (1 error, 0 warnings)

[10:55:02] 'eslint' errored after 1.9 s
[10:55:02] ESLintError in plugin 'gulp-eslint'
Message:
    Failed with 1 error

npm ERR! Darwin 15.5.0
npm ERR! argv "/usr/local/bin/node" "/usr/local/bin/npm" "run" "eslint"
npm ERR! node v4.4.7
npm ERR! npm  v2.15.8
npm ERR! code ELIFECYCLE
npm ERR! Project-name@version eslint: `gulp eslint`
npm ERR! Exit status 1
npm ERR!
npm ERR! Failed at the Project-name@version eslint script 'gulp eslint'.
npm ERR! This is most likely a problem with the Project-name package,
npm ERR! not with npm itself.
npm ERR! Tell the author that this fails on your system:
npm ERR!     gulp eslint
npm ERR! You can get information on how to open an issue for this project with:
npm ERR!     npm bugs Project-name
npm ERR! Or if that isn't available, you can get their info via:
npm ERR!
npm ERR!     npm owner ls Project-name
npm ERR! There is likely additional logging output above.

npm ERR! Please include the following file with any support request:
npm ERR!     ~/path/to/project/root/npm-debug.log

[ilyavolodin]

I think this is correct behavior. catch is reserved word in JavaScript, so it shouldn't be used as function name. If you rename catch function to something else, rule is working correctly. Somebody else correct me if I'm wrong.

[not-an-aardvark]

This is a bug. In this context catch is just a method name -- I think the rule is assuming that any curly brace before a catch keyword ends a try statement, but that's not the case here.

[kojinkai]

@ilyavolodin Thanks for the feedback, I half expected this to be the case as I realise catch is a reserved keyword but wasn't sure whether, as @not-an-aardvark mentioned, with catch being just a method name this was a bug or intended behaviour. Thanks again for taking the time to review the issue.