.eslintrc.yml

---
root: true

env:
    node: true
    es6: true

parserOptions:
    sourceType: script
    ecmaVersion: 2018

globals:
    # Allow the Intl global but don't allow it to be overwritten
    Intl: false

plugins:
    - promise
    - unicorn
    - node

extends:
    - 'eslint:recommended'
    - 'plugin:promise/recommended'
    - 'plugin:unicorn/recommended'
    - 'plugin:node/recommended'

rules:

### POSSIBLE ERRORS
    getter-return: error
    no-await-in-loop: error
    # This seems like a good idea, but questionable value?
    no-prototype-builtins: off
    no-template-curly-in-string: error
    no-misleading-character-class: error
    valid-jsdoc:
        - error
        - 
            prefer:
                return: returns
                arg: param
                class: constructor
            preferType:
                object: Object
                bool: boolean

### BEST PRACTICES
    accessor-pairs: error
    array-callback-return: error
    block-scoped-var: error
    class-methods-use-this: warn
    consistent-return: error
    curly:
        - error
        - all
    default-case: error
    dot-location:
        - error
        - property
    dot-notation: error
    eqeqeq: error
    guard-for-in: error
    max-classes-per-file:
        - error
        - 1
    no-alert: error
    no-async-promise-executor: error
    no-caller: error
    no-div-regex: warn
    no-else-return: error
    no-empty-function: warn
    no-eval: error
    no-extend-native: error
    no-extra-bind: error
    no-floating-decimal: error
    no-global-assign: error
    no-implicit-coercion: warn
    no-implicit-globals: error
    no-implied-eval: error
    no-invalid-this: error
    no-iterator: error
    no-labels: error
    no-lone-blocks: error
    no-loop-func: error
    no-multi-spaces: error
    no-multi-str: error
    no-new: error
    no-new-func: error
    no-new-wrappers: error
    no-octal-escape: error
    no-proto: error
    no-return-assign: error
    no-return-await: error
    no-script-url: error
    no-self-compare: error
    no-sequences: error
    no-throw-literal: error
    no-unmodified-loop-condition: error
    no-unused-expressions: error
    no-useless-call: error
    no-useless-concat: error
    no-useless-return: error
    no-void: error
    no-with: error
    prefer-promise-reject-errors: error
    radix: error
    require-await: warn
    require-unicode-regexp: error
    wrap-iife: error
    yoda:
        - error
        - never
    # no-restricted-properties

### STRICT MODE
    strict:
        - error
        - safe

### VARIABLES
    no-catch-shadow: error
    no-delete-var: error
    no-shadow: error
    no-shadow-restricted-names: error
    # Turn on someday, just use null everywhere if we can
    no-undefined: off
    # We allow some unused args
    no-unused-vars:
        - error
        -
            args: after-used
    no-use-before-define: error

### NODE AND COMMONJS
    callback-return: error
    global-require: error
    handle-callback-err:
        - error
        - '^.*(e|E)rr'
    no-buffer-constructor: error
    no-mixed-requires: error
    no-new-require: error
    no-path-concat: error
    no-process-exit: error
    no-sync: error

### STYLISTIC ISSUES
    array-bracket-newline: off # prettier
    array-element-newline: off # prettier
    block-spacing: error
    brace-style:
        - error
        - 1tbs
        - 
            allowSingleLine: true
    camelcase:
        - error
        - 
            properties: never
    comma-dangle:
        - error
        - only-multiline
    comma-spacing: error
    comma-style:
        - error
        - last
    consistent-this:
        - error
        - self
    eol-last: error
    func-call-spacing: error
    func-name-matching: error
    func-style:
        - error
        - declaration
        - 
            allowArrowFunctions: true
    implicit-arrow-linebreak: off # prettier
    # This rule can be customized for switch/case etc.
    indent: off # prettier
    key-spacing: error
    keyword-spacing:
        - error
        - 
            before: true
            after: true
    linebreak-style:
        - error
        - unix
    lines-between-class-members: error
    max-depth: error
    # We should turn this on to enforce readable line lengths
    max-len:
        - off
        - 120
    max-params:
        - error
        - 6
    max-statements-per-line:
        - error
        - 
            max: 1
    multiline-ternary: off # prettier
    new-cap: error
    new-parens: error
    newline-per-chained-call:
        - error
        - 
            ignoreChainWithDepth: 2
    no-array-constructor: error
    no-bitwise: warn
    no-continue: error
    no-lonely-if: error
    no-mixed-operators: error
    no-multi-assign: error
    no-multiple-empty-lines: error
    no-negated-condition: error
    no-nested-ternary: error
    no-new-object: error
    no-plusplus:
        - error
        - 
            allowForLoopAfterthoughts: true
    no-trailing-spaces: error
    no-unneeded-ternary: error
    no-whitespace-before-property: error
    one-var-declaration-per-line: error
    operator-assignment: error
    quote-props:
        - error
        - as-needed
    quotes:
        - error
        - single
        - avoid-escape
    require-jsdoc:
        - error
        - 
            require:
                FunctionDeclaration: true
                MethodDefinition: true
                ClassDeclaration: true
    semi:
        - error
        - always
    semi-spacing: error
    semi-style:
        - error
        - last
    space-before-blocks: error
    space-before-function-paren:
        - error
        - never
    space-infix-ops: error
    space-unary-ops:
        - error
        - 
            words: true
            nonwords: false
    spaced-comment:
        - error
        - always
    switch-colon-spacing: error
    template-tag-spacing:
        - error
        - never
    unicode-bom: error

### ES6
    arrow-body-style:
        - error
        - as-needed
    arrow-parens: off # prettier
    arrow-spacing: error
    generator-star-spacing:
        - error
        - after
    no-confusing-arrow: off # prettier
    no-duplicate-imports:
        - error
        - 
            includeExports: true
    no-useless-computed-key: error
    no-useless-constructor: error
    no-useless-rename: error
    no-var: error
    object-shorthand:
        - warn
        - always
        - 
            avoidQuotes: true
            avoidExplicitReturnArrows: true
    prefer-arrow-callback:
        - error
        - 
            allowNamedFunctions: true
    # Turn on when we don't support older Node.js versions
    prefer-destructuring: off
    prefer-numeric-literals: error
    prefer-rest-params: error
    prefer-spread: error
    prefer-object-spread: error
    prefer-template: error
    rest-spread-spacing:
        - error
        - never
    symbol-description: error
    template-curly-spacing:
        - error
        - never
    yield-star-spacing:
        - error
        - after
### PROMISES
    promise/no-nesting: off
    # We do not need to use bluebird; all promises should be native
    promise/no-native: off
    promise/no-promise-in-callback: error
    promise/no-callback-in-promise: error
    promise/avoid-new: error
    promise/no-return-in-finally: error
    promise/prefer-await-to-callbacks: error
    promise/prefer-await-to-then: error

### UNICORN
    unicorn/custom-error-definition: error
    unicorn/no-fn-reference-in-iterator: error
    unicorn/no-new-buffer: error

### NODE
    node/no-deprecated-api: error
    node/exports-style:
        - error
        - module.exports