---
  env:
    node: true

  rules:

    # Trivia:     stroustrup is the designer and original implementor of C++.
    # Disallows:  `else`, `elseif` and `catch` and the same line as the closing }.
    brace-style:
      - 2
      - "stroustrup"

    # Disallows:  `var fn = function() {};`
    # Allows:     `function fn() {}` and `internals.fn = function() {};`
    func-style:
      - 2
      - "declaration"

    # Disallows:  `for-in` loops without `hasOwnProperty`
    guard-for-in: 2

    # Disallows:  `var num = .5;` `var num = 2.;` `var num = -.7;`
    no-floating-decimal: 2

    # Disallows:  `var foo = bar ? baz : qux === quxx ? bing : bam;`
    no-nested-ternary: 2

    # Require use of the second argument for parseInt() i.e a radix.
    radix: 2

    # Disallow:
    #   var x = "Line 1 \
    #            Line 2";
    no-multi-str: 2

    # Warn about "todo" and "fixme" comments.
    no-warning-comments:
      - 1
      -
        terms:
        - "todo"
        - "fixme"
        location: "anywhere"

    # Line length should have a maximum.
    max-len:
      - 2     # Count this as an error.
      - 100   # 100 characters long lines.
      - 2     # Each tab counts as two characters.

    # Warn if the jsdoc is invalid
    valid-jsdoc:
      - 1
      -
        requireReturn: false
        # prefer:
        #   return: "return"

    # Require immediate function invocation to be wrapped in parentheses.
    wrap-iife: 2

    # Allows the use of `this_is_a_variable_name`
    camelcase: 0

    # Enforce single quotes
    quotes:
      - 2
      - "single"
      - "avoid-escape"

    # Disallow use of variables before they are defined
    no-use-before-define: 0

    # Allow Dangling Underscores in Identifiers. e.g `var _foo = 1;
    # Since MongoDB has the property `_id` which raises this error.
    no-underscore-dangle: 0

    # Enforces error handling in callbacks
    handle-callback-err: 2

    # Err if string is concatenated with __dirname or __filename. Use path module.
    no-path-concat: 2

    # Require Just One var Statement Per Scope: OFF
    one-var: 0

    # Disallow Mixed Requires
    # TODO: Make this an error in the future.
    no-mixed-requires:
      - 1
      - true  # Grouping of requires

    # Generates warnings when variables are used outside of the block in which they were defined.
    block-scoped-var: 2

    # Require Variable Declarations to be at the Top
    # NOTE: This rule breaks when using 'use strict'; at the top of the files
    vars-on-top: 0

    # Require Spaces Around Infix Operators e.g. `a+b` will raise an error, `a + b` will not.
    space-infix-ops: 2

    # Disallow declaration of variables that are not used in the code
    no-unused-vars:
      - 2
      -
        vars: "all"  # checks all variables for usage, including those in the global scope
        args: "none" # do not check arguments

    # Allow use of process.exit()
    # This would be turned on for module.
    no-process-exit: 0

    # Error if "use strict" is omitted
    strict: 2

    # Disallow unnecessary use of "use strict"; when already in strict mode
    no-extra-strict: 2

    # Allow global strict in node projects since each file has its own function scope
    no-global-strict: 0

    # Disallow use of new operator with the require function
    no-new-require: 2

    # Enforce newline at the end of file, with no multiple empty lines
    eol-last: 2

    # Require a capital letter for constructors
    new-cap: 2

    # Disallow Spaces in Function Calls
    no-spaced-func: 2

    # Disallow Spaces Before Semicolon
    no-space-before-semi: 2

    # Disallow trailing spaces at the end of lines
    no-trailing-spaces: 2

    # Require spaces following keywords
    space-after-keywords: 2

    # Require spaces following return, throw, and case
    space-return-throw-case: 2

    # Disallow spaces inside of parentheses
    # space-in-parens:
    #   - 2
    #   - "never"

    # Disallow mixed spaces and tabs for indentation
    no-mixed-spaces-and-tabs: 2

    # Enforce Semicolons
    semi:
      - 2
      - "always"

    # Require Default Case in Switch Statements
    default-case: 2

    # Require Following Curly Brace Conventions
    curly: 2

    # Require use of dot notation whenever possible
    dot-notation: 2

    # Require the use of === and !==
    eqeqeq: 2

    # Disallow use of eval()
    no-eval: 2

    # Disallow adding to native types
    no-extend-native: 1

    # Warn Case Statement Fallthrough
    no-fallthrough: 1

    # Disallow Implied eval()
    # Example:
    #   setTimeout("alert('Hi!');", 100);
    no-implied-eval: 2

    # Disallow Reassignment of Native Objects
    # Example:
    #   String = "hello world";
    #   var String;
    no-native-reassign: 2

    # Disallow use of new operator when not part of the assignment or comparison
    # Example
    #   new Thing();              // Error
    #   var thing = new Thing();  // OK
    no-new: 2

    # Disallow Redeclaring Variables
    # Example:
    #   var a = 3;
    #   var a = 10;
    no-redeclare: 2

    # Disallow use of void operator.
    no-void: 2

    # No with Statements
    no-with: 2

    # Ensures that the results of typeof are compared against a valid string.
    valid-typeof: 2

    # Disallow Yoda Conditions
    # Example:
    #   if ("red" === color) {}
    yoda:
      - 2
      - "never"

    # Disallow Self Compare
    # Example:
    #   if (x === x) {}
    no-self-compare: 2

    # Disallow Empty Block Statements
    # Example:
    #   if (foo) {
    #   }
    no-empty: 2

    # Disallow Extra Semicolons
    # Example:
    #   var x = 5;;
    no-extra-semi: 2

    # Disallow Duplicate Keys
    # Example:
    #   var foo = {
    #     bar: "baz",
    #     bar: "qux"
    #   };
    no-dupe-keys: 2

    # Disallow Dangling Commas
    # Example:
    #   var foo = {
    #     bar: "baz",
    #     qux: "quux",
    #   };
    no-comma-dangle: 2

    # Disallow Assignment in Conditional Expressions
    # Example:
    #   if (c = "f") {
    #     // ...
    #   }
    no-cond-assign: 2

    # Warn about Extra Boolean Casts
    no-extra-boolean-cast: 1

    # Disallow Unreachable Code
    # Example:
    #   function fn() {
    #     x = 1;
    #     return x;
    #     x = 3; // this will never execute
    #   }
    no-unreachable: 2