no-nested-ternary: Add option to traverse deeper than one level

Tell us about your environment

• ESLint Version: 4.19.1
• Node Version: v9.6.1
• npm Version: 5.6.0

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

Configuration

{
  "root": true,

  "plugins": [
    "react"
  ],

  "extends": [
    "eslint:recommended",
    "plugin:react/recommended",
    "prettier",
    "prettier/react"
  ],

  "env": {
    "es6": true
  },

  "parser": "babel-eslint",
  "parserOptions": {
    "ecmaVersion": 6,
    "ecmaFeatures": {
      "jsx": true
    },
    "sourceType": "script"
  },

  "rules": {
    // Disabled, May conflict with Prettier
    "quotes": [0, "single", { "allowTemplateLiterals": true }],
    "max-len": [0, { "code": 100, "ignoreUrls": true }],
    "arrow-parens": [0, "as-needed"],
    "arrow-spacing": 0,
    "brace-style": [0, "1tbs", { "allowSingleLine": false }],
    "eol-last": 0,
    "indent": [0, 2, { "SwitchCase": 1 }],
    "key-spacing": [0, { "mode": "strict" }],
    "keyword-spacing": 0,
    "no-extra-semi": 0,
    "no-mixed-spaces-and-tabs": 0,
    "no-multi-spaces": [0, {
      "exceptions": {
        "VariableDeclarator": true,
        "ImportDeclaration": true,
        "ImportSpecifier": true,
        "AssignmentExpression": true,
        "ClassProperty": true
      }
    }],
    "no-multiple-empty-lines": [0, { "max": 1 }],
    "no-trailing-spaces": 0,
    "object-curly-spacing": [0, "always"],
    "operator-linebreak": [0, "after", { "overrides": { "?": "before", ":": "before" } }],
    "semi": [0, "always"],
    "semi-spacing": [0, {"before": false, "after": true}],
    "semi-style": [0, "last"],
    "space-before-blocks": [0, "always"],
    "switch-colon-spacing": [0, {"before": false, "after": true}],
    "func-call-spacing": [0, "never"],
    "function-paren-newline": [0, "multiline"],

    "react/jsx-closing-bracket-location": [0, "line-aligned"],
    "react/jsx-closing-tag-location": 0,
    "react/jsx-equals-spacing": [0, "never"],
    "react/jsx-indent": [0, 2],
    "react/jsx-tag-spacing": [0, {
      "closingSlash": "never",
      "beforeSelfClosing": "always",
      "afterOpening": "never"
    }],
    "react/jsx-wrap-multilines": [0, {
      "declaration": false,
      "assignment": false,
      "return": true
    }],

    // Warning
    "no-console": 1,
    "no-debugger": 1,
    "no-undef": 1,
    "no-unreachable": 1,
    "no-unused-vars": [1, { "vars": "all", "args": "after-used" }],
    "newline-after-var": [1, "always"],
    "newline-before-return": 1,
    "prefer-arrow-callback": 1,
    "prefer-const": 1,
    "no-multi-assign": 1,
    "no-warning-comments": [1, { "terms": ["fixme", "todo", "hack", "review", "xxx"] }],
    "no-useless-constructor": 1,

    "linebreak-style": [1, "unix"],
    "no-else-return": 1,
    "curly": [1, "all"],
    "no-inline-comments": 1,
    "spaced-comment": [1, "always", { "exceptions": ["-"] }],
    "no-nested-ternary": 1,
    "no-unneeded-ternary": [1, { "defaultAssignment": false }],
    "no-var": 1,
    "eqeqeq": [1, "always"],
    "no-return-assign": 1,
    "no-multi-str": 1,
    "padding-line-between-statements": [
      1,
      { "blankLine": "always", "prev": "*", "next": "return" },
      { "blankLine": "always", "prev": ["const", "let"], "next": "*"},
      { "blankLine": "any",    "prev": ["const", "let"], "next": ["const", "let"]}
    ],

    // React

    // Disabled - Should be fixed and set as warning
    "react/no-deprecated": 0,
    "react/display-name": 0,
    "react/react-in-jsx-scope": 0,
    "react/forbid-component-props": [0, { "forbid": ["className", "style"] }],
    "react/no-is-mounted": 0,

    // Disabled
    "react/forbid-elements": 0,
    "react/forbid-prop-types": [0, { "forbid": ["any", "array", "object"] }],
    "react/no-array-index-key": 0,
    "react/no-danger": 0,
    "react/no-set-state": 0,
    "react/prop-types": 0,
    "react/require-default-props": 0,
    "react/sort-prop-types": 0,
    "react/require-optimization": 0,
    "react/style-prop-object": 0,

    "react/jsx-curly-spacing": [0, "always", { "allowMultiline": true }],
    "react/jsx-first-prop-new-line": 0,
    "react/jsx-handler-names": 0,
    "react/jsx-indent-props": [0, 2],
    "react/jsx-key": 0,
    "react/jsx-max-props-per-line": 0,
    "react/jsx-no-comment-textnodes": 0,
    "react/jsx-no-literals": 0,
    "react/no-unescaped-entities": 0,
    "react/jsx-sort-props": 0,

    // Warning
    "react/default-props-match-prop-types": 1,
    "react/forbid-foreign-prop-types": 1,
    "react/no-children-prop": 1,
    "react/no-danger-with-children": 1,
    "react/no-did-mount-set-state": 1,
    "react/no-did-update-set-state": 1,
    "react/no-will-update-set-state": 1,
    "react/no-multi-comp": [1, { "ignoreStateless": true }],
    "react/no-redundant-should-component-update": 1,
    "react/no-string-refs": 1,
    "react/no-unused-prop-types": 1,
    "react/prefer-es6-class": [1, "always"],
    "react/prefer-stateless-function": [1, { "ignorePureComponents": true }],
    "react/self-closing-comp": 1,
    "react/sort-comp": [1, {
      "order": [
        "static-methods",
        "lifecycle",
        "/^on.+$/",
        "/^(get|set)(?!(InitialState$|DefaultProps$|ChildContext$)).+$/",
        "everything-else",
        "/^render.+$/",
        "render"
      ]
    }],
    "react/void-dom-elements-no-children": 1,

    "react/jsx-boolean-value": [1, "never"],
    "react/jsx-filename-extension": [1, { "extensions": [".js", ".jsx"] }],
    "react/jsx-no-bind": [1, {
      "ignoreRefs": true,
      "allowArrowFunctions": true
    }],
    "react/jsx-no-target-blank": 1,
    "react/jsx-pascal-case": 1
  },

  // Override config (only applied to files that match the given globs)
  "overrides": [
    // Server only (all JS files except Client)
    {
      "files": ["**/*.js"],
      "excludedFiles": ["assets/**/*.js"],
      "env": {
        "node": true
      },
      "rules": {
        "strict": [1, "global"]
      }
    },

    // Client only
    {
      "files": ["assets/js/**/*.{js,jsx}"],
      "env": {
        "browser": true,
        "amd": true
      },
      "rules": {
        "strict": [1, "never"]
      }
    },

    // Client only test files
    {
      "files": ["assets/js/**/_*.{js,jsx}", "**/*.test.js"],
      "env": {
        "mocha": true,
        "jasmine": true,
        "qunit": true
      }
    }
  ]
}

What did you do? Please include the actual source code causing the issue, as well as the command that you used to run ESLint.

const nestedTernary =
  global.foo === 0
    ? 'foo is 0, and '
    : 'foo is not 0, and ' + (global.bar === 0 ? 'bar is 0' : 'bar is not 0');

eslint temp.js

What did you expect to happen? I expected ESLint to warn me about the nested ternary What actually happened? Please include the actual, raw output from ESLint. Did not warn, it didn’t catch the nested ternary when it’s surrounded by braces and part of a statement.

Proposal

Based on the comments, maybe it’s best to add an option to traverse the tree deeper than only one level.

[eslint-deprecated[bot]]

Unfortunately, it looks like there wasn’t enough interest from the team or community to implement this change. While we wish we’d be able to accommodate everyone’s requests, we do need to prioritize. We’ve found that issues failing to reach accepted status after 21 days tend to never be accepted, and as such, we close those issues. This doesn’t mean the idea isn’t interesting or useful, just that it’s not something the team can commit to.

Thanks for contributing to ESLint and we appreciate your understanding.

[kaicataldo]

It feels off to me that it would look arbitrarily deep - @not-an-aardvark’s example is a good one. Disallowing the code in that example also doesn’t feel like it’s staying true to the spirit of the rule, since the ternary in the function doesn’t create any confusion with the outer ternary.

Could it stop looking when a new scope is created?