Gecko [ gandhischool.edu.np ]

Name	Size	Permission
utils	[ DIR ]	dr-xr-xr-x
accessor-pairs.js	11.71 KB	-rw-rw-rw-
array-bracket-newline.js	9.45 KB	-rw-rw-rw-
array-bracket-spacing.js	8.96 KB	-rw-rw-rw-
array-callback-return.js	15.5 KB	-rw-rw-rw-
array-element-newline.js	10.9 KB	-rw-rw-rw-
arrow-body-style.js	12.67 KB	-rw-rw-rw-
arrow-parens.js	7.61 KB	-rw-rw-rw-
arrow-spacing.js	5.17 KB	-rw-rw-rw-
block-scoped-var.js	4.24 KB	-rw-rw-rw-
block-spacing.js	5.8 KB	-rw-rw-rw-
brace-style.js	8.04 KB	-rw-rw-rw-
callback-return.js	6.41 KB	-rw-rw-rw-
camelcase.js	13.66 KB	-rw-rw-rw-
capitalized-comments.js	10.48 KB	-rw-rw-rw-
class-methods-use-this.js	6.02 KB	-rw-rw-rw-
comma-dangle.js	13.53 KB	-rw-rw-rw-
comma-spacing.js	6.87 KB	-rw-rw-rw-
comma-style.js	11.72 KB	-rw-rw-rw-
complexity.js	5.6 KB	-rw-rw-rw-
computed-property-spacing.js	7.45 KB	-rw-rw-rw-
consistent-return.js	6.91 KB	-rw-rw-rw-
consistent-this.js	4.99 KB	-rw-rw-rw-
constructor-super.js	15.19 KB	-rw-rw-rw-
curly.js	18.93 KB	-rw-rw-rw-
default-case-last.js	1.21 KB	-rw-rw-rw-
default-case.js	2.77 KB	-rw-rw-rw-
default-param-last.js	1.55 KB	-rw-rw-rw-
dot-location.js	3.43 KB	-rw-rw-rw-
dot-notation.js	6.6 KB	-rw-rw-rw-
eol-last.js	4.01 KB	-rw-rw-rw-
eqeqeq.js	5.65 KB	-rw-rw-rw-
for-direction.js	5 KB	-rw-rw-rw-
func-call-spacing.js	9.77 KB	-rw-rw-rw-
func-name-matching.js	9.91 KB	-rw-rw-rw-
func-names.js	6.3 KB	-rw-rw-rw-
func-style.js	2.85 KB	-rw-rw-rw-
function-call-argument-newline...	4.31 KB	-rw-rw-rw-
function-paren-newline.js	11.61 KB	-rw-rw-rw-
generator-star-spacing.js	7.01 KB	-rw-rw-rw-
getter-return.js	6.87 KB	-rw-rw-rw-
global-require.js	2.44 KB	-rw-rw-rw-
grouped-accessor-pairs.js	7.46 KB	-rw-rw-rw-
guard-for-in.js	2.31 KB	-rw-rw-rw-
handle-callback-err.js	3.06 KB	-rw-rw-rw-
id-blacklist.js	7.54 KB	-rw-rw-rw-
id-denylist.js	7.04 KB	-rw-rw-rw-
id-length.js	6.51 KB	-rw-rw-rw-
id-match.js	11.04 KB	-rw-rw-rw-
implicit-arrow-linebreak.js	2.88 KB	-rw-rw-rw-
indent-legacy.js	43.59 KB	-rw-rw-rw-
indent.js	76.54 KB	-rw-rw-rw-
index.js	17.89 KB	-rw-rw-rw-
init-declarations.js	4.38 KB	-rw-rw-rw-
jsx-quotes.js	2.98 KB	-rw-rw-rw-
key-spacing.js	26.36 KB	-rw-rw-rw-
keyword-spacing.js	23.7 KB	-rw-rw-rw-
line-comment-position.js	4.09 KB	-rw-rw-rw-
linebreak-style.js	3.48 KB	-rw-rw-rw-
lines-around-comment.js	17.85 KB	-rw-rw-rw-
lines-around-directive.js	7.6 KB	-rw-rw-rw-
lines-between-class-members.js	11.15 KB	-rw-rw-rw-
logical-assignment-operators.j...	21.38 KB	-rw-rw-rw-
max-classes-per-file.js	2.58 KB	-rw-rw-rw-
max-depth.js	4.68 KB	-rw-rw-rw-
max-len.js	15.81 KB	-rw-rw-rw-
max-lines-per-function.js	6.92 KB	-rw-rw-rw-
max-lines.js	5.95 KB	-rw-rw-rw-
max-nested-callbacks.js	3.48 KB	-rw-rw-rw-
max-params.js	3.1 KB	-rw-rw-rw-
max-statements-per-line.js	7.35 KB	-rw-rw-rw-
max-statements.js	5.81 KB	-rw-rw-rw-
multiline-comment-style.js	21.22 KB	-rw-rw-rw-
multiline-ternary.js	7.62 KB	-rw-rw-rw-
new-cap.js	9.3 KB	-rw-rw-rw-
new-parens.js	3.19 KB	-rw-rw-rw-
newline-after-var.js	9.46 KB	-rw-rw-rw-
newline-before-return.js	7.87 KB	-rw-rw-rw-
newline-per-chained-call.js	4.04 KB	-rw-rw-rw-
no-alert.js	4.25 KB	-rw-rw-rw-
no-array-constructor.js	4.38 KB	-rw-rw-rw-
no-async-promise-executor.js	1.11 KB	-rw-rw-rw-
no-await-in-loop.js	2.73 KB	-rw-rw-rw-
no-bitwise.js	3.5 KB	-rw-rw-rw-
no-buffer-constructor.js	1.4 KB	-rw-rw-rw-
no-caller.js	1.18 KB	-rw-rw-rw-
no-case-declarations.js	1.83 KB	-rw-rw-rw-
no-catch-shadow.js	2.51 KB	-rw-rw-rw-
no-class-assign.js	1.73 KB	-rw-rw-rw-
no-compare-neg-zero.js	1.9 KB	-rw-rw-rw-
no-cond-assign.js	5.52 KB	-rw-rw-rw-
no-confusing-arrow.js	2.9 KB	-rw-rw-rw-
no-console.js	7.17 KB	-rw-rw-rw-
no-const-assign.js	1.52 KB	-rw-rw-rw-
no-constant-binary-expression....	20.41 KB	-rw-rw-rw-
no-constant-condition.js	4.77 KB	-rw-rw-rw-
no-constructor-return.js	1.57 KB	-rw-rw-rw-
no-continue.js	886 B	-rw-rw-rw-
no-control-regex.js	4.58 KB	-rw-rw-rw-
no-debugger.js	959 B	-rw-rw-rw-
no-delete-var.js	983 B	-rw-rw-rw-
no-div-regex.js	1.42 KB	-rw-rw-rw-
no-dupe-args.js	2.36 KB	-rw-rw-rw-
no-dupe-class-members.js	3.29 KB	-rw-rw-rw-
no-dupe-else-if.js	4.51 KB	-rw-rw-rw-
no-dupe-keys.js	3.88 KB	-rw-rw-rw-
no-duplicate-case.js	2.04 KB	-rw-rw-rw-
no-duplicate-imports.js	9.28 KB	-rw-rw-rw-
no-else-return.js	15.71 KB	-rw-rw-rw-
no-empty-character-class.js	2.23 KB	-rw-rw-rw-
no-empty-function.js	4.63 KB	-rw-rw-rw-
no-empty-pattern.js	2.38 KB	-rw-rw-rw-
no-empty-static-block.js	1.22 KB	-rw-rw-rw-
no-empty.js	3.08 KB	-rw-rw-rw-
no-eq-null.js	1.22 KB	-rw-rw-rw-
no-eval.js	9.34 KB	-rw-rw-rw-
no-ex-assign.js	1.43 KB	-rw-rw-rw-
no-extend-native.js	6.5 KB	-rw-rw-rw-
no-extra-bind.js	7.39 KB	-rw-rw-rw-
no-extra-boolean-cast.js	11.7 KB	-rw-rw-rw-
no-extra-label.js	5.04 KB	-rw-rw-rw-
no-extra-parens.js	52.03 KB	-rw-rw-rw-
no-extra-semi.js	4.99 KB	-rw-rw-rw-
no-fallthrough.js	6.89 KB	-rw-rw-rw-
no-floating-decimal.js	2.42 KB	-rw-rw-rw-
no-func-assign.js	2.2 KB	-rw-rw-rw-
no-global-assign.js	2.97 KB	-rw-rw-rw-
no-implicit-coercion.js	12.97 KB	-rw-rw-rw-
no-implicit-globals.js	5.48 KB	-rw-rw-rw-
no-implied-eval.js	4.54 KB	-rw-rw-rw-
no-import-assign.js	7.25 KB	-rw-rw-rw-
no-inline-comments.js	3.29 KB	-rw-rw-rw-
no-inner-declarations.js	2.96 KB	-rw-rw-rw-
no-invalid-regexp.js	6.3 KB	-rw-rw-rw-
no-invalid-this.js	5.01 KB	-rw-rw-rw-
no-irregular-whitespace.js	9.93 KB	-rw-rw-rw-
no-iterator.js	1.28 KB	-rw-rw-rw-
no-label-var.js	2.36 KB	-rw-rw-rw-
no-labels.js	4.38 KB	-rw-rw-rw-
no-lone-blocks.js	4.23 KB	-rw-rw-rw-
no-lonely-if.js	3.65 KB	-rw-rw-rw-
no-loop-func.js	6.16 KB	-rw-rw-rw-
no-loss-of-precision.js	8.07 KB	-rw-rw-rw-
no-magic-numbers.js	9.26 KB	-rw-rw-rw-
no-misleading-character-class....	9.87 KB	-rw-rw-rw-
no-mixed-operators.js	7.58 KB	-rw-rw-rw-
no-mixed-requires.js	7.26 KB	-rw-rw-rw-
no-mixed-spaces-and-tabs.js	3.67 KB	-rw-rw-rw-
no-multi-assign.js	1.76 KB	-rw-rw-rw-
no-multi-spaces.js	5.04 KB	-rw-rw-rw-
no-multi-str.js	1.8 KB	-rw-rw-rw-
no-multiple-empty-lines.js	6.25 KB	-rw-rw-rw-
no-native-reassign.js	2.99 KB	-rw-rw-rw-
no-negated-condition.js	2.9 KB	-rw-rw-rw-
no-negated-in-lhs.js	1.16 KB	-rw-rw-rw-
no-nested-ternary.js	1.12 KB	-rw-rw-rw-
no-new-func.js	2.98 KB	-rw-rw-rw-
no-new-native-nonconstructor.j...	2.11 KB	-rw-rw-rw-
no-new-object.js	1.72 KB	-rw-rw-rw-
no-new-require.js	1.17 KB	-rw-rw-rw-
no-new-symbol.js	1.58 KB	-rw-rw-rw-
no-new-wrappers.js	1.7 KB	-rw-rw-rw-
no-new.js	1.04 KB	-rw-rw-rw-
no-nonoctal-decimal-escape.js	5.47 KB	-rw-rw-rw-
no-obj-calls.js	2.7 KB	-rw-rw-rw-
no-object-constructor.js	3.55 KB	-rw-rw-rw-
no-octal-escape.js	1.44 KB	-rw-rw-rw-
no-octal.js	1.01 KB	-rw-rw-rw-
no-param-reassign.js	8.42 KB	-rw-rw-rw-
no-path-concat.js	1.68 KB	-rw-rw-rw-
no-plusplus.js	3.1 KB	-rw-rw-rw-
no-process-env.js	1.19 KB	-rw-rw-rw-
no-process-exit.js	1.24 KB	-rw-rw-rw-
no-promise-executor-return.js	8.54 KB	-rw-rw-rw-
no-proto.js	1.21 KB	-rw-rw-rw-
no-prototype-builtins.js	5.83 KB	-rw-rw-rw-
no-redeclare.js	5.67 KB	-rw-rw-rw-
no-regex-spaces.js	6.42 KB	-rw-rw-rw-
no-restricted-exports.js	7.1 KB	-rw-rw-rw-
no-restricted-globals.js	3.79 KB	-rw-rw-rw-
no-restricted-imports.js	16.6 KB	-rw-rw-rw-
no-restricted-modules.js	6.9 KB	-rw-rw-rw-
no-restricted-properties.js	6.17 KB	-rw-rw-rw-
no-restricted-syntax.js	2.17 KB	-rw-rw-rw-
no-return-assign.js	2.62 KB	-rw-rw-rw-
no-return-await.js	5.02 KB	-rw-rw-rw-
no-script-url.js	1.72 KB	-rw-rw-rw-
no-self-assign.js	5.5 KB	-rw-rw-rw-
no-self-compare.js	1.81 KB	-rw-rw-rw-
no-sequences.js	4.67 KB	-rw-rw-rw-
no-setter-return.js	7.07 KB	-rw-rw-rw-
no-shadow-restricted-names.js	2.16 KB	-rw-rw-rw-
no-shadow.js	12.31 KB	-rw-rw-rw-
no-spaced-func.js	2.42 KB	-rw-rw-rw-
no-sparse-arrays.js	1.17 KB	-rw-rw-rw-
no-sync.js	1.65 KB	-rw-rw-rw-
no-tabs.js	2.45 KB	-rw-rw-rw-
no-template-curly-in-string.js	1.15 KB	-rw-rw-rw-
no-ternary.js	889 B	-rw-rw-rw-
no-this-before-super.js	10.87 KB	-rw-rw-rw-
no-throw-literal.js	1.28 KB	-rw-rw-rw-
no-trailing-spaces.js	6.72 KB	-rw-rw-rw-
no-undef-init.js	2.35 KB	-rw-rw-rw-
no-undef.js	2.3 KB	-rw-rw-rw-
no-undefined.js	2.24 KB	-rw-rw-rw-
no-underscore-dangle.js	12.79 KB	-rw-rw-rw-
no-unexpected-multiline.js	4.19 KB	-rw-rw-rw-
no-unmodified-loop-condition.j...	11.65 KB	-rw-rw-rw-
no-unneeded-ternary.js	6.79 KB	-rw-rw-rw-
no-unreachable-loop.js	5.94 KB	-rw-rw-rw-
no-unreachable.js	8.9 KB	-rw-rw-rw-
no-unsafe-finally.js	3.91 KB	-rw-rw-rw-
no-unsafe-negation.js	4.63 KB	-rw-rw-rw-
no-unsafe-optional-chaining.js	6.97 KB	-rw-rw-rw-
no-unused-expressions.js	6.08 KB	-rw-rw-rw-
no-unused-labels.js	4.55 KB	-rw-rw-rw-
no-unused-private-class-member...	7.68 KB	-rw-rw-rw-
no-unused-vars.js	27 KB	-rw-rw-rw-
no-use-before-define.js	10.88 KB	-rw-rw-rw-
no-useless-backreference.js	7.57 KB	-rw-rw-rw-
no-useless-call.js	2.99 KB	-rw-rw-rw-
no-useless-catch.js	1.71 KB	-rw-rw-rw-
no-useless-computed-key.js	6.3 KB	-rw-rw-rw-
no-useless-concat.js	3.24 KB	-rw-rw-rw-
no-useless-constructor.js	5.75 KB	-rw-rw-rw-
no-useless-escape.js	13.18 KB	-rw-rw-rw-
no-useless-rename.js	5.88 KB	-rw-rw-rw-
no-useless-return.js	14.01 KB	-rw-rw-rw-
no-var.js	12.14 KB	-rw-rw-rw-
no-void.js	1.72 KB	-rw-rw-rw-
no-warning-comments.js	7.12 KB	-rw-rw-rw-
no-whitespace-before-property....	3.92 KB	-rw-rw-rw-
no-with.js	876 B	-rw-rw-rw-
nonblock-statement-body-positi...	4.56 KB	-rw-rw-rw-
object-curly-newline.js	11.53 KB	-rw-rw-rw-
object-curly-spacing.js	11.61 KB	-rw-rw-rw-
object-property-newline.js	3.8 KB	-rw-rw-rw-
object-shorthand.js	21.78 KB	-rw-rw-rw-
one-var-declaration-per-line.j...	2.86 KB	-rw-rw-rw-
one-var.js	22.37 KB	-rw-rw-rw-
operator-assignment.js	8.58 KB	-rw-rw-rw-
operator-linebreak.js	9.88 KB	-rw-rw-rw-
padded-blocks.js	10.79 KB	-rw-rw-rw-
padding-line-between-statement...	18.85 KB	-rw-rw-rw-
prefer-arrow-callback.js	14.33 KB	-rw-rw-rw-
prefer-const.js	18.27 KB	-rw-rw-rw-
prefer-destructuring.js	10.93 KB	-rw-rw-rw-
prefer-exponentiation-operator...	7.58 KB	-rw-rw-rw-
prefer-named-capture-group.js	5.84 KB	-rw-rw-rw-
prefer-numeric-literals.js	5.7 KB	-rw-rw-rw-
prefer-object-has-own.js	4.24 KB	-rw-rw-rw-
prefer-object-spread.js	10.45 KB	-rw-rw-rw-
prefer-promise-reject-errors.j...	5.37 KB	-rw-rw-rw-
prefer-reflect.js	4.59 KB	-rw-rw-rw-
prefer-regex-literals.js	18.06 KB	-rw-rw-rw-
prefer-rest-params.js	3.39 KB	-rw-rw-rw-
prefer-spread.js	2.78 KB	-rw-rw-rw-
prefer-template.js	11.15 KB	-rw-rw-rw-
quote-props.js	11.82 KB	-rw-rw-rw-
quotes.js	12.41 KB	-rw-rw-rw-
radix.js	6.75 KB	-rw-rw-rw-
require-atomic-updates.js	11.1 KB	-rw-rw-rw-
require-await.js	3.27 KB	-rw-rw-rw-
require-jsdoc.js	3.77 KB	-rw-rw-rw-
require-unicode-regexp.js	5.1 KB	-rw-rw-rw-
require-yield.js	2.05 KB	-rw-rw-rw-
rest-spread-spacing.js	4.03 KB	-rw-rw-rw-
semi-spacing.js	8.71 KB	-rw-rw-rw-
semi-style.js	5.24 KB	-rw-rw-rw-
semi.js	15.87 KB	-rw-rw-rw-
sort-imports.js	10.62 KB	-rw-rw-rw-
sort-keys.js	7.16 KB	-rw-rw-rw-
sort-vars.js	4.04 KB	-rw-rw-rw-
space-before-blocks.js	7.14 KB	-rw-rw-rw-
space-before-function-paren.js	5.87 KB	-rw-rw-rw-
space-in-parens.js	10.55 KB	-rw-rw-rw-
space-infix-ops.js	6.42 KB	-rw-rw-rw-
space-unary-ops.js	12.39 KB	-rw-rw-rw-
spaced-comment.js	12.85 KB	-rw-rw-rw-
strict.js	10.37 KB	-rw-rw-rw-
switch-colon-spacing.js	4.9 KB	-rw-rw-rw-
symbol-description.js	2.04 KB	-rw-rw-rw-
template-curly-spacing.js	4.74 KB	-rw-rw-rw-
template-tag-spacing.js	3.08 KB	-rw-rw-rw-
unicode-bom.js	2.15 KB	-rw-rw-rw-
use-isnan.js	4.64 KB	-rw-rw-rw-
valid-jsdoc.js	20.08 KB	-rw-rw-rw-
valid-typeof.js	4.92 KB	-rw-rw-rw-
vars-on-top.js	5.17 KB	-rw-rw-rw-
wrap-iife.js	7.8 KB	-rw-rw-rw-
wrap-regex.js	1.85 KB	-rw-rw-rw-
yield-star-spacing.js	4.31 KB	-rw-rw-rw-
yoda.js	11.89 KB	-rw-rw-rw-

Code Editor : no-unused-vars.js

/**
 * @fileoverview Rule to flag declared but unused variables
 * @author Ilya Volodin
 */

"use strict";

//------------------------------------------------------------------------------
// Requirements
//------------------------------------------------------------------------------

const astUtils = require("./utils/ast-utils");

//------------------------------------------------------------------------------
// Typedefs
//------------------------------------------------------------------------------

/**
 * Bag of data used for formatting the `unusedVar` lint message.
 * @typedef {Object} UnusedVarMessageData
 * @property {string} varName The name of the unused var.
 * @property {'defined'|'assigned a value'} action Description of the vars state.
 * @property {string} additional Any additional info to be appended at the end.
 */

//------------------------------------------------------------------------------
// Rule Definition
//------------------------------------------------------------------------------

/** @type {import('../shared/types').Rule} */
module.exports = {
    meta: {
        type: "problem",

docs: {
            description: "Disallow unused variables",
            recommended: true,
            url: "https://eslint.org/docs/latest/rules/no-unused-vars"
        },

schema: [
            {
                oneOf: [
                    {
                        enum: ["all", "local"]
                    },
                    {
                        type: "object",
                        properties: {
                            vars: {
                                enum: ["all", "local"]
                            },
                            varsIgnorePattern: {
                                type: "string"
                            },
                            args: {
                                enum: ["all", "after-used", "none"]
                            },
                            ignoreRestSiblings: {
                                type: "boolean"
                            },
                            argsIgnorePattern: {
                                type: "string"
                            },
                            caughtErrors: {
                                enum: ["all", "none"]
                            },
                            caughtErrorsIgnorePattern: {
                                type: "string"
                            },
                            destructuredArrayIgnorePattern: {
                                type: "string"
                            }
                        },
                        additionalProperties: false
                    }
                ]
            }
        ],

messages: {
            unusedVar: "'{{varName}}' is {{action}} but never used{{additional}}."
        }
    },

create(context) {
        const sourceCode = context.sourceCode;

const REST_PROPERTY_TYPE = /^(?:RestElement|(?:Experimental)?RestProperty)$/u;

const config = {
            vars: "all",
            args: "after-used",
            ignoreRestSiblings: false,
            caughtErrors: "none"
        };

const firstOption = context.options[0];

if (firstOption) {
            if (typeof firstOption === "string") {
                config.vars = firstOption;
            } else {
                config.vars = firstOption.vars || config.vars;
                config.args = firstOption.args || config.args;
                config.ignoreRestSiblings = firstOption.ignoreRestSiblings || config.ignoreRestSiblings;
                config.caughtErrors = firstOption.caughtErrors || config.caughtErrors;

if (firstOption.varsIgnorePattern) {
                    config.varsIgnorePattern = new RegExp(firstOption.varsIgnorePattern, "u");
                }

if (firstOption.argsIgnorePattern) {
                    config.argsIgnorePattern = new RegExp(firstOption.argsIgnorePattern, "u");
                }

if (firstOption.caughtErrorsIgnorePattern) {
                    config.caughtErrorsIgnorePattern = new RegExp(firstOption.caughtErrorsIgnorePattern, "u");
                }

if (firstOption.destructuredArrayIgnorePattern) {
                    config.destructuredArrayIgnorePattern = new RegExp(firstOption.destructuredArrayIgnorePattern, "u");
                }
            }
        }

/**
         * Generates the message data about the variable being defined and unused,
         * including the ignore pattern if configured.
         * @param {Variable} unusedVar eslint-scope variable object.
         * @returns {UnusedVarMessageData} The message data to be used with this unused variable.
         */
        function getDefinedMessageData(unusedVar) {
            const defType = unusedVar.defs && unusedVar.defs[0] && unusedVar.defs[0].type;
            let type;
            let pattern;

if (defType === "CatchClause" && config.caughtErrorsIgnorePattern) {
                type = "args";
                pattern = config.caughtErrorsIgnorePattern.toString();
            } else if (defType === "Parameter" && config.argsIgnorePattern) {
                type = "args";
                pattern = config.argsIgnorePattern.toString();
            } else if (defType !== "Parameter" && config.varsIgnorePattern) {
                type = "vars";
                pattern = config.varsIgnorePattern.toString();
            }

const additional = type ? `. Allowed unused ${type} must match ${pattern}` : "";

return {
                varName: unusedVar.name,
                action: "defined",
                additional
            };
        }

/**
         * Generate the warning message about the variable being
         * assigned and unused, including the ignore pattern if configured.
         * @param {Variable} unusedVar eslint-scope variable object.
         * @returns {UnusedVarMessageData} The message data to be used with this unused variable.
         */
        function getAssignedMessageData(unusedVar) {
            const def = unusedVar.defs[0];
            let additional = "";

if (config.destructuredArrayIgnorePattern && def && def.name.parent.type === "ArrayPattern") {
                additional = `. Allowed unused elements of array destructuring patterns must match ${config.destructuredArrayIgnorePattern.toString()}`;
            } else if (config.varsIgnorePattern) {
                additional = `. Allowed unused vars must match ${config.varsIgnorePattern.toString()}`;
            }

return {
                varName: unusedVar.name,
                action: "assigned a value",
                additional
            };
        }

//--------------------------------------------------------------------------
        // Helpers
        //--------------------------------------------------------------------------

const STATEMENT_TYPE = /(?:Statement|Declaration)$/u;

/**
         * Determines if a given variable is being exported from a module.
         * @param {Variable} variable eslint-scope variable object.
         * @returns {boolean} True if the variable is exported, false if not.
         * @private
         */
        function isExported(variable) {

const definition = variable.defs[0];

if (definition) {

let node = definition.node;

if (node.type === "VariableDeclarator") {
                    node = node.parent;
                } else if (definition.type === "Parameter") {
                    return false;
                }

return node.parent.type.indexOf("Export") === 0;
            }
            return false;

}

/**
         * Checks whether a node is a sibling of the rest property or not.
         * @param {ASTNode} node a node to check
         * @returns {boolean} True if the node is a sibling of the rest property, otherwise false.
         */
        function hasRestSibling(node) {
            return node.type === "Property" &&
                node.parent.type === "ObjectPattern" &&
                REST_PROPERTY_TYPE.test(node.parent.properties[node.parent.properties.length - 1].type);
        }

/**
         * Determines if a variable has a sibling rest property
         * @param {Variable} variable eslint-scope variable object.
         * @returns {boolean} True if the variable is exported, false if not.
         * @private
         */
        function hasRestSpreadSibling(variable) {
            if (config.ignoreRestSiblings) {
                const hasRestSiblingDefinition = variable.defs.some(def => hasRestSibling(def.name.parent));
                const hasRestSiblingReference = variable.references.some(ref => hasRestSibling(ref.identifier.parent));

return hasRestSiblingDefinition || hasRestSiblingReference;
            }

return false;
        }

/**
         * Determines if a reference is a read operation.
         * @param {Reference} ref An eslint-scope Reference
         * @returns {boolean} whether the given reference represents a read operation
         * @private
         */
        function isReadRef(ref) {
            return ref.isRead();
        }

/**
         * Determine if an identifier is referencing an enclosing function name.
         * @param {Reference} ref The reference to check.
         * @param {ASTNode[]} nodes The candidate function nodes.
         * @returns {boolean} True if it's a self-reference, false if not.
         * @private
         */
        function isSelfReference(ref, nodes) {
            let scope = ref.from;

while (scope) {
                if (nodes.includes(scope.block)) {
                    return true;
                }

scope = scope.upper;
            }

return false;
        }

/**
         * Gets a list of function definitions for a specified variable.
         * @param {Variable} variable eslint-scope variable object.
         * @returns {ASTNode[]} Function nodes.
         * @private
         */
        function getFunctionDefinitions(variable) {
            const functionDefinitions = [];

variable.defs.forEach(def => {
                const { type, node } = def;

// FunctionDeclarations
                if (type === "FunctionName") {
                    functionDefinitions.push(node);
                }

// FunctionExpressions
                if (type === "Variable" && node.init &&
                    (node.init.type === "FunctionExpression" || node.init.type === "ArrowFunctionExpression")) {
                    functionDefinitions.push(node.init);
                }
            });
            return functionDefinitions;
        }

/**
         * Checks the position of given nodes.
         * @param {ASTNode} inner A node which is expected as inside.
         * @param {ASTNode} outer A node which is expected as outside.
         * @returns {boolean} `true` if the `inner` node exists in the `outer` node.
         * @private
         */
        function isInside(inner, outer) {
            return (
                inner.range[0] >= outer.range[0] &&
                inner.range[1] <= outer.range[1]
            );
        }

/**
         * Checks whether a given node is unused expression or not.
         * @param {ASTNode} node The node itself
         * @returns {boolean} The node is an unused expression.
         * @private
         */
        function isUnusedExpression(node) {
            const parent = node.parent;

if (parent.type === "ExpressionStatement") {
                return true;
            }

if (parent.type === "SequenceExpression") {
                const isLastExpression = parent.expressions[parent.expressions.length - 1] === node;

if (!isLastExpression) {
                    return true;
                }
                return isUnusedExpression(parent);
            }

return false;
        }

/**
         * If a given reference is left-hand side of an assignment, this gets
         * the right-hand side node of the assignment.
         *
         * In the following cases, this returns null.
         *
         * - The reference is not the LHS of an assignment expression.
         * - The reference is inside of a loop.
         * - The reference is inside of a function scope which is different from
         *   the declaration.
         * @param {eslint-scope.Reference} ref A reference to check.
         * @param {ASTNode} prevRhsNode The previous RHS node.
         * @returns {ASTNode|null} The RHS node or null.
         * @private
         */
        function getRhsNode(ref, prevRhsNode) {
            const id = ref.identifier;
            const parent = id.parent;
            const refScope = ref.from.variableScope;
            const varScope = ref.resolved.scope.variableScope;
            const canBeUsedLater = refScope !== varScope || astUtils.isInLoop(id);

/*
             * Inherits the previous node if this reference is in the node.
             * This is for `a = a + a`-like code.
             */
            if (prevRhsNode && isInside(id, prevRhsNode)) {
                return prevRhsNode;
            }

if (parent.type === "AssignmentExpression" &&
                isUnusedExpression(parent) &&
                id === parent.left &&
                !canBeUsedLater
            ) {
                return parent.right;
            }
            return null;
        }

/**
         * Checks whether a given function node is stored to somewhere or not.
         * If the function node is stored, the function can be used later.
         * @param {ASTNode} funcNode A function node to check.
         * @param {ASTNode} rhsNode The RHS node of the previous assignment.
         * @returns {boolean} `true` if under the following conditions:
         *      - the funcNode is assigned to a variable.
         *      - the funcNode is bound as an argument of a function call.
         *      - the function is bound to a property and the object satisfies above conditions.
         * @private
         */
        function isStorableFunction(funcNode, rhsNode) {
            let node = funcNode;
            let parent = funcNode.parent;

while (parent && isInside(parent, rhsNode)) {
                switch (parent.type) {
                    case "SequenceExpression":
                        if (parent.expressions[parent.expressions.length - 1] !== node) {
                            return false;
                        }
                        break;

case "CallExpression":
                    case "NewExpression":
                        return parent.callee !== node;

case "AssignmentExpression":
                    case "TaggedTemplateExpression":
                    case "YieldExpression":
                        return true;

default:
                        if (STATEMENT_TYPE.test(parent.type)) {

/*
                             * If it encountered statements, this is a complex pattern.
                             * Since analyzing complex patterns is hard, this returns `true` to avoid false positive.
                             */
                            return true;
                        }
                }

node = parent;
                parent = parent.parent;
            }

return false;
        }

/**
         * Checks whether a given Identifier node exists inside of a function node which can be used later.
         *
         * "can be used later" means:
         * - the function is assigned to a variable.
         * - the function is bound to a property and the object can be used later.
         * - the function is bound as an argument of a function call.
         *
         * If a reference exists in a function which can be used later, the reference is read when the function is called.
         * @param {ASTNode} id An Identifier node to check.
         * @param {ASTNode} rhsNode The RHS node of the previous assignment.
         * @returns {boolean} `true` if the `id` node exists inside of a function node which can be used later.
         * @private
         */
        function isInsideOfStorableFunction(id, rhsNode) {
            const funcNode = astUtils.getUpperFunction(id);

return (
                funcNode &&
                isInside(funcNode, rhsNode) &&
                isStorableFunction(funcNode, rhsNode)
            );
        }

/**
         * Checks whether a given reference is a read to update itself or not.
         * @param {eslint-scope.Reference} ref A reference to check.
         * @param {ASTNode} rhsNode The RHS node of the previous assignment.
         * @returns {boolean} The reference is a read to update itself.
         * @private
         */
        function isReadForItself(ref, rhsNode) {
            const id = ref.identifier;
            const parent = id.parent;

return ref.isRead() && (

// self update. e.g. `a += 1`, `a++`
                (
                    (
                        parent.type === "AssignmentExpression" &&
                        parent.left === id &&
                        isUnusedExpression(parent) &&
                        !astUtils.isLogicalAssignmentOperator(parent.operator)
                    ) ||
                    (
                        parent.type === "UpdateExpression" &&
                        isUnusedExpression(parent)
                    )
                ) ||

// in RHS of an assignment for itself. e.g. `a = a + 1`
                (
                    rhsNode &&
                    isInside(id, rhsNode) &&
                    !isInsideOfStorableFunction(id, rhsNode)
                )
            );
        }

/**
         * Determine if an identifier is used either in for-in or for-of loops.
         * @param {Reference} ref The reference to check.
         * @returns {boolean} whether reference is used in the for-in loops
         * @private
         */
        function isForInOfRef(ref) {
            let target = ref.identifier.parent;

// "for (var ...) { return; }"
            if (target.type === "VariableDeclarator") {
                target = target.parent.parent;
            }

if (target.type !== "ForInStatement" && target.type !== "ForOfStatement") {
                return false;
            }

// "for (...) { return; }"
            if (target.body.type === "BlockStatement") {
                target = target.body.body[0];

// "for (...) return;"
            } else {
                target = target.body;
            }

// For empty loop body
            if (!target) {
                return false;
            }

return target.type === "ReturnStatement";
        }

/**
         * Determines if the variable is used.
         * @param {Variable} variable The variable to check.
         * @returns {boolean} True if the variable is used
         * @private
         */
        function isUsedVariable(variable) {
            const functionNodes = getFunctionDefinitions(variable),
                isFunctionDefinition = functionNodes.length > 0;
            let rhsNode = null;

return variable.references.some(ref => {
                if (isForInOfRef(ref)) {
                    return true;
                }

const forItself = isReadForItself(ref, rhsNode);

rhsNode = getRhsNode(ref, rhsNode);

return (
                    isReadRef(ref) &&
                    !forItself &&
                    !(isFunctionDefinition && isSelfReference(ref, functionNodes))
                );
            });
        }

/**
         * Checks whether the given variable is after the last used parameter.
         * @param {eslint-scope.Variable} variable The variable to check.
         * @returns {boolean} `true` if the variable is defined after the last
         * used parameter.
         */
        function isAfterLastUsedArg(variable) {
            const def = variable.defs[0];
            const params = sourceCode.getDeclaredVariables(def.node);
            const posteriorParams = params.slice(params.indexOf(variable) + 1);

// If any used parameters occur after this parameter, do not report.
            return !posteriorParams.some(v => v.references.length > 0 || v.eslintUsed);
        }

/**
         * Gets an array of variables without read references.
         * @param {Scope} scope an eslint-scope Scope object.
         * @param {Variable[]} unusedVars an array that saving result.
         * @returns {Variable[]} unused variables of the scope and descendant scopes.
         * @private
         */
        function collectUnusedVariables(scope, unusedVars) {
            const variables = scope.variables;
            const childScopes = scope.childScopes;
            let i, l;

if (scope.type !== "global" || config.vars === "all") {
                for (i = 0, l = variables.length; i < l; ++i) {
                    const variable = variables[i];

// skip a variable of class itself name in the class scope
                    if (scope.type === "class" && scope.block.id === variable.identifiers[0]) {
                        continue;
                    }

// skip function expression names and variables marked with markVariableAsUsed()
                    if (scope.functionExpressionScope || variable.eslintUsed) {
                        continue;
                    }

// skip implicit "arguments" variable
                    if (scope.type === "function" && variable.name === "arguments" && variable.identifiers.length === 0) {
                        continue;
                    }

// explicit global variables don't have definitions.
                    const def = variable.defs[0];

if (def) {
                        const type = def.type;
                        const refUsedInArrayPatterns = variable.references.some(ref => ref.identifier.parent.type === "ArrayPattern");

// skip elements of array destructuring patterns
                        if (
                            (
                                def.name.parent.type === "ArrayPattern" ||
                                refUsedInArrayPatterns
                            ) &&
                            config.destructuredArrayIgnorePattern &&
                            config.destructuredArrayIgnorePattern.test(def.name.name)
                        ) {
                            continue;
                        }

// skip catch variables
                        if (type === "CatchClause") {
                            if (config.caughtErrors === "none") {
                                continue;
                            }

// skip ignored parameters
                            if (config.caughtErrorsIgnorePattern && config.caughtErrorsIgnorePattern.test(def.name.name)) {
                                continue;
                            }
                        }

if (type === "Parameter") {

// skip any setter argument
                            if ((def.node.parent.type === "Property" || def.node.parent.type === "MethodDefinition") && def.node.parent.kind === "set") {
                                continue;
                            }

// if "args" option is "none", skip any parameter
                            if (config.args === "none") {
                                continue;
                            }

// skip ignored parameters
                            if (config.argsIgnorePattern && config.argsIgnorePattern.test(def.name.name)) {
                                continue;
                            }

// if "args" option is "after-used", skip used variables
                            if (config.args === "after-used" && astUtils.isFunction(def.name.parent) && !isAfterLastUsedArg(variable)) {
                                continue;
                            }
                        } else {

// skip ignored variables
                            if (config.varsIgnorePattern && config.varsIgnorePattern.test(def.name.name)) {
                                continue;
                            }
                        }
                    }

if (!isUsedVariable(variable) && !isExported(variable) && !hasRestSpreadSibling(variable)) {
                        unusedVars.push(variable);
                    }
                }
            }

for (i = 0, l = childScopes.length; i < l; ++i) {
                collectUnusedVariables(childScopes[i], unusedVars);
            }

return unusedVars;
        }

//--------------------------------------------------------------------------
        // Public
        //--------------------------------------------------------------------------

return {
            "Program:exit"(programNode) {
                const unusedVars = collectUnusedVariables(sourceCode.getScope(programNode), []);

for (let i = 0, l = unusedVars.length; i < l; ++i) {
                    const unusedVar = unusedVars[i];

// Report the first declaration.
                    if (unusedVar.defs.length > 0) {

// report last write reference, https://github.com/eslint/eslint/issues/14324
                        const writeReferences = unusedVar.references.filter(ref => ref.isWrite() && ref.from.variableScope === unusedVar.scope.variableScope);

let referenceToReport;

if (writeReferences.length > 0) {
                            referenceToReport = writeReferences[writeReferences.length - 1];
                        }

context.report({
                            node: referenceToReport ? referenceToReport.identifier : unusedVar.identifiers[0],
                            messageId: "unusedVar",
                            data: unusedVar.references.some(ref => ref.isWrite())
                                ? getAssignedMessageData(unusedVar)
                                : getDefinedMessageData(unusedVar)
                        });

// If there are no regular declaration, report the first `/*globals*/` comment directive.
                    } else if (unusedVar.eslintExplicitGlobalComments) {
                        const directiveComment = unusedVar.eslintExplicitGlobalComments[0];

context.report({
                            node: programNode,
                            loc: astUtils.getNameLocationInGlobalDirectiveComment(sourceCode, directiveComment, unusedVar.name),
                            messageId: "unusedVar",
                            data: getDefinedMessageData(unusedVar)
                        });
                    }
                }
            }
        };

}
};

${this.title}

Code Editor : no-unused-vars.js