Showing 112 of 112 total issues
Identifier 'hailing_frequency' is not in camel case. Open
if (message === hailing_frequency || message === hailing_frequency + '--help' || message === hailing_frequency + 'help' || message === hailing_frequency + 'commands') {
- Read upRead up
- Exclude checks
Require Camelcase (camelcase)
When it comes to naming variables, style guides generally fall into one of two camps: camelcase (variableName
) and underscores (variable_name
). This rule focuses on using the camelcase approach. If your style guide calls for camelcasing your variable names, then this rule is for you!
Rule Details
This rule looks for any underscores (_
) located within the source code. It ignores leading and trailing underscores and only checks those in the middle of a variable name. If ESLint decides that the variable is a constant (all uppercase), then no warning will be thrown. Otherwise, a warning will be thrown. This rule only flags definitions and assignments but not function calls. In case of ES6 import
statements, this rule only targets the name of the variable that will be imported into the local module scope.
Options
This rule has an object option:
-
"properties": "always"
(default) enforces camelcase style for property names -
"properties": "never"
does not check property names
always
Examples of incorrect code for this rule with the default { "properties": "always" }
option:
/*eslint camelcase: "error"*/
import { no_camelcased } from "external-module"
var my_favorite_color = "#112C85";
function do_something() {
// ...
}
obj.do_something = function() {
// ...
};
var obj = {
my_pref: 1
};
Examples of correct code for this rule with the default { "properties": "always" }
option:
/*eslint camelcase: "error"*/
import { no_camelcased as camelCased } from "external-module";
var myFavoriteColor = "#112C85";
var _myFavoriteColor = "#112C85";
var myFavoriteColor_ = "#112C85";
var MY_FAVORITE_COLOR = "#112C85";
var foo = bar.baz_boom;
var foo = { qux: bar.baz_boom };
obj.do_something();
do_something();
new do_something();
var { category_id: category } = query;
never
Examples of correct code for this rule with the { "properties": "never" }
option:
/*eslint camelcase: ["error", {properties: "never"}]*/
var obj = {
my_pref: 1
};
When Not To Use It
If you have established coding standards using a different naming convention (separating words with underscores), turn this rule off. Source: http://eslint.org/docs/rules/
Identifier 'hailing_frequency' is not in camel case. Open
if (message === hailing_frequency || message === hailing_frequency + '--help' || message === hailing_frequency + 'help' || message === hailing_frequency + 'commands') {
- Read upRead up
- Exclude checks
Require Camelcase (camelcase)
When it comes to naming variables, style guides generally fall into one of two camps: camelcase (variableName
) and underscores (variable_name
). This rule focuses on using the camelcase approach. If your style guide calls for camelcasing your variable names, then this rule is for you!
Rule Details
This rule looks for any underscores (_
) located within the source code. It ignores leading and trailing underscores and only checks those in the middle of a variable name. If ESLint decides that the variable is a constant (all uppercase), then no warning will be thrown. Otherwise, a warning will be thrown. This rule only flags definitions and assignments but not function calls. In case of ES6 import
statements, this rule only targets the name of the variable that will be imported into the local module scope.
Options
This rule has an object option:
-
"properties": "always"
(default) enforces camelcase style for property names -
"properties": "never"
does not check property names
always
Examples of incorrect code for this rule with the default { "properties": "always" }
option:
/*eslint camelcase: "error"*/
import { no_camelcased } from "external-module"
var my_favorite_color = "#112C85";
function do_something() {
// ...
}
obj.do_something = function() {
// ...
};
var obj = {
my_pref: 1
};
Examples of correct code for this rule with the default { "properties": "always" }
option:
/*eslint camelcase: "error"*/
import { no_camelcased as camelCased } from "external-module";
var myFavoriteColor = "#112C85";
var _myFavoriteColor = "#112C85";
var myFavoriteColor_ = "#112C85";
var MY_FAVORITE_COLOR = "#112C85";
var foo = bar.baz_boom;
var foo = { qux: bar.baz_boom };
obj.do_something();
do_something();
new do_something();
var { category_id: category } = query;
never
Examples of correct code for this rule with the { "properties": "never" }
option:
/*eslint camelcase: ["error", {properties: "never"}]*/
var obj = {
my_pref: 1
};
When Not To Use It
If you have established coding standards using a different naming convention (separating words with underscores), turn this rule off. Source: http://eslint.org/docs/rules/
Identifier 'giphy_type' is not in camel case. Open
if (messages.length === 0) giphy_type = 'random'
- Read upRead up
- Exclude checks
Require Camelcase (camelcase)
When it comes to naming variables, style guides generally fall into one of two camps: camelcase (variableName
) and underscores (variable_name
). This rule focuses on using the camelcase approach. If your style guide calls for camelcasing your variable names, then this rule is for you!
Rule Details
This rule looks for any underscores (_
) located within the source code. It ignores leading and trailing underscores and only checks those in the middle of a variable name. If ESLint decides that the variable is a constant (all uppercase), then no warning will be thrown. Otherwise, a warning will be thrown. This rule only flags definitions and assignments but not function calls. In case of ES6 import
statements, this rule only targets the name of the variable that will be imported into the local module scope.
Options
This rule has an object option:
-
"properties": "always"
(default) enforces camelcase style for property names -
"properties": "never"
does not check property names
always
Examples of incorrect code for this rule with the default { "properties": "always" }
option:
/*eslint camelcase: "error"*/
import { no_camelcased } from "external-module"
var my_favorite_color = "#112C85";
function do_something() {
// ...
}
obj.do_something = function() {
// ...
};
var obj = {
my_pref: 1
};
Examples of correct code for this rule with the default { "properties": "always" }
option:
/*eslint camelcase: "error"*/
import { no_camelcased as camelCased } from "external-module";
var myFavoriteColor = "#112C85";
var _myFavoriteColor = "#112C85";
var myFavoriteColor_ = "#112C85";
var MY_FAVORITE_COLOR = "#112C85";
var foo = bar.baz_boom;
var foo = { qux: bar.baz_boom };
obj.do_something();
do_something();
new do_something();
var { category_id: category } = query;
never
Examples of correct code for this rule with the { "properties": "never" }
option:
/*eslint camelcase: ["error", {properties: "never"}]*/
var obj = {
my_pref: 1
};
When Not To Use It
If you have established coding standards using a different naming convention (separating words with underscores), turn this rule off. Source: http://eslint.org/docs/rules/
Unnecessary escape character: \╯. Open
const count = (message.match(/\(\╯\°\□\°\)\╯\︵ \┻\━\┻/g) || []).length
- Read upRead up
- Exclude checks
Disallow unnecessary escape usage (no-useless-escape)
Escaping non-special characters in strings, template literals, and regular expressions doesn't have any effect, as demonstrated in the following example:
let foo = "hol\a"; // > foo = "hola"
let bar = `${foo}\!`; // > bar = "hola!"
let baz = /\:/ // same functionality with /:/
Rule Details
This rule flags escapes that can be safely removed without changing behavior.
Examples of incorrect code for this rule:
/*eslint no-useless-escape: "error"*/
"\'";
'\"';
"\#";
"\e";
`\"`;
`\"${foo}\"`;
`\#{foo}`;
/\!/;
/\@/;
Examples of correct code for this rule:
/*eslint no-useless-escape: "error"*/
"\"";
'\'';
"\x12";
"\u00a9";
"\371";
"xs\u2111";
`\``;
`\${${foo}\}`;
`$\{${foo}\}`;
/\\/g;
/\t/g;
/\w\$\*\^\./;
When Not To Use It
If you don't want to be notified about unnecessary escapes, you can safely disable this rule. Source: http://eslint.org/docs/rules/
Import in body of module; reorder to top. Open
import del from 'del'
- Read upRead up
- Exclude checks
For more information visit Source: http://eslint.org/docs/rules/
Unnecessary escape character: \┻. Open
const count = (message.match(/\(\╯\°\□\°\)\╯\︵ \┻\━\┻/g) || []).length
- Read upRead up
- Exclude checks
Disallow unnecessary escape usage (no-useless-escape)
Escaping non-special characters in strings, template literals, and regular expressions doesn't have any effect, as demonstrated in the following example:
let foo = "hol\a"; // > foo = "hola"
let bar = `${foo}\!`; // > bar = "hola!"
let baz = /\:/ // same functionality with /:/
Rule Details
This rule flags escapes that can be safely removed without changing behavior.
Examples of incorrect code for this rule:
/*eslint no-useless-escape: "error"*/
"\'";
'\"';
"\#";
"\e";
`\"`;
`\"${foo}\"`;
`\#{foo}`;
/\!/;
/\@/;
Examples of correct code for this rule:
/*eslint no-useless-escape: "error"*/
"\"";
'\'';
"\x12";
"\u00a9";
"\371";
"xs\u2111";
`\``;
`\${${foo}\}`;
`$\{${foo}\}`;
/\\/g;
/\t/g;
/\w\$\*\^\./;
When Not To Use It
If you don't want to be notified about unnecessary escapes, you can safely disable this rule. Source: http://eslint.org/docs/rules/
Unnecessary escape character: \━. Open
const count = (message.match(/\(\╯\°\□\°\)\╯\︵ \┻\━\┻/g) || []).length
- Read upRead up
- Exclude checks
Disallow unnecessary escape usage (no-useless-escape)
Escaping non-special characters in strings, template literals, and regular expressions doesn't have any effect, as demonstrated in the following example:
let foo = "hol\a"; // > foo = "hola"
let bar = `${foo}\!`; // > bar = "hola!"
let baz = /\:/ // same functionality with /:/
Rule Details
This rule flags escapes that can be safely removed without changing behavior.
Examples of incorrect code for this rule:
/*eslint no-useless-escape: "error"*/
"\'";
'\"';
"\#";
"\e";
`\"`;
`\"${foo}\"`;
`\#{foo}`;
/\!/;
/\@/;
Examples of correct code for this rule:
/*eslint no-useless-escape: "error"*/
"\"";
'\'';
"\x12";
"\u00a9";
"\371";
"xs\u2111";
`\``;
`\${${foo}\}`;
`$\{${foo}\}`;
/\\/g;
/\t/g;
/\w\$\*\^\./;
When Not To Use It
If you don't want to be notified about unnecessary escapes, you can safely disable this rule. Source: http://eslint.org/docs/rules/
Unnecessary escape character: \°. Open
const count = (message.match(/\(\╯\°\□\°\)\╯\︵ \┻\━\┻/g) || []).length
- Read upRead up
- Exclude checks
Disallow unnecessary escape usage (no-useless-escape)
Escaping non-special characters in strings, template literals, and regular expressions doesn't have any effect, as demonstrated in the following example:
let foo = "hol\a"; // > foo = "hola"
let bar = `${foo}\!`; // > bar = "hola!"
let baz = /\:/ // same functionality with /:/
Rule Details
This rule flags escapes that can be safely removed without changing behavior.
Examples of incorrect code for this rule:
/*eslint no-useless-escape: "error"*/
"\'";
'\"';
"\#";
"\e";
`\"`;
`\"${foo}\"`;
`\#{foo}`;
/\!/;
/\@/;
Examples of correct code for this rule:
/*eslint no-useless-escape: "error"*/
"\"";
'\'';
"\x12";
"\u00a9";
"\371";
"xs\u2111";
`\``;
`\${${foo}\}`;
`$\{${foo}\}`;
/\\/g;
/\t/g;
/\w\$\*\^\./;
When Not To Use It
If you don't want to be notified about unnecessary escapes, you can safely disable this rule. Source: http://eslint.org/docs/rules/
Unnecessary escape character: \︵. Open
const count = (message.match(/\(\╯\°\□\°\)\╯\︵ \┻\━\┻/g) || []).length
- Read upRead up
- Exclude checks
Disallow unnecessary escape usage (no-useless-escape)
Escaping non-special characters in strings, template literals, and regular expressions doesn't have any effect, as demonstrated in the following example:
let foo = "hol\a"; // > foo = "hola"
let bar = `${foo}\!`; // > bar = "hola!"
let baz = /\:/ // same functionality with /:/
Rule Details
This rule flags escapes that can be safely removed without changing behavior.
Examples of incorrect code for this rule:
/*eslint no-useless-escape: "error"*/
"\'";
'\"';
"\#";
"\e";
`\"`;
`\"${foo}\"`;
`\#{foo}`;
/\!/;
/\@/;
Examples of correct code for this rule:
/*eslint no-useless-escape: "error"*/
"\"";
'\'';
"\x12";
"\u00a9";
"\371";
"xs\u2111";
`\``;
`\${${foo}\}`;
`$\{${foo}\}`;
/\\/g;
/\t/g;
/\w\$\*\^\./;
When Not To Use It
If you don't want to be notified about unnecessary escapes, you can safely disable this rule. Source: http://eslint.org/docs/rules/
Unnecessary escape character: \┻. Open
const count = (message.match(/\(\╯\°\□\°\)\╯\︵ \┻\━\┻/g) || []).length
- Read upRead up
- Exclude checks
Disallow unnecessary escape usage (no-useless-escape)
Escaping non-special characters in strings, template literals, and regular expressions doesn't have any effect, as demonstrated in the following example:
let foo = "hol\a"; // > foo = "hola"
let bar = `${foo}\!`; // > bar = "hola!"
let baz = /\:/ // same functionality with /:/
Rule Details
This rule flags escapes that can be safely removed without changing behavior.
Examples of incorrect code for this rule:
/*eslint no-useless-escape: "error"*/
"\'";
'\"';
"\#";
"\e";
`\"`;
`\"${foo}\"`;
`\#{foo}`;
/\!/;
/\@/;
Examples of correct code for this rule:
/*eslint no-useless-escape: "error"*/
"\"";
'\'';
"\x12";
"\u00a9";
"\371";
"xs\u2111";
`\``;
`\${${foo}\}`;
`$\{${foo}\}`;
/\\/g;
/\t/g;
/\w\$\*\^\./;
When Not To Use It
If you don't want to be notified about unnecessary escapes, you can safely disable this rule. Source: http://eslint.org/docs/rules/
Import in body of module; reorder to top. Open
import Random from 'random-js'
- Read upRead up
- Exclude checks
For more information visit Source: http://eslint.org/docs/rules/
'describe' is defined but never used. Open
/* global describe, it */
- Read upRead up
- Exclude checks
Disallow Unused Variables (no-unused-vars)
Variables that are declared and not used anywhere in the code are most likely an error due to incomplete refactoring. Such variables take up space in the code and can lead to confusion by readers.
Rule Details
This rule is aimed at eliminating unused variables, functions, and parameters of functions.
A variable is considered to be used if any of the following are true:
- It represents a function that is called (
doSomething()
) - It is read (
var y = x
) - It is passed into a function as an argument (
doSomething(x)
) - It is read inside of a function that is passed to another function (
doSomething(function() { foo(); })
)
A variable is not considered to be used if it is only ever assigned to (var x = 5
) or declared.
Examples of incorrect code for this rule:
/*eslint no-unused-vars: "error"*/
/*global some_unused_var*/
// It checks variables you have defined as global
some_unused_var = 42;
var x;
// Write-only variables are not considered as used.
var y = 10;
y = 5;
// A read for a modification of itself is not considered as used.
var z = 0;
z = z + 1;
// By default, unused arguments cause warnings.
(function(foo) {
return 5;
})();
// Unused recursive functions also cause warnings.
function fact(n) {
if (n < 2) return 1;
return n * fact(n - 1);
}
// When a function definition destructures an array, unused entries from the array also cause warnings.
function getY([x, y]) {
return y;
}
Examples of correct code for this rule:
/*eslint no-unused-vars: "error"*/
var x = 10;
alert(x);
// foo is considered used here
myFunc(function foo() {
// ...
}.bind(this));
(function(foo) {
return foo;
})();
var myFunc;
myFunc = setTimeout(function() {
// myFunc is considered used
myFunc();
}, 50);
// Only the second argument from the descructured array is used.
function getY([, y]) {
return y;
}
exported
In environments outside of CommonJS or ECMAScript modules, you may use var
to create a global variable that may be used by other scripts. You can use the /* exported variableName */
comment block to indicate that this variable is being exported and therefore should not be considered unused.
Note that /* exported */
has no effect for any of the following:
- when the environment is
node
orcommonjs
- when
parserOptions.sourceType
ismodule
- when
ecmaFeatures.globalReturn
istrue
The line comment // exported variableName
will not work as exported
is not line-specific.
Examples of correct code for /* exported variableName */
operation:
/* exported global_var */
var global_var = 42;
Options
This rule takes one argument which can be a string or an object. The string settings are the same as those of the vars
property (explained below).
By default this rule is enabled with all
option for variables and after-used
for arguments.
{
"rules": {
"no-unused-vars": ["error", { "vars": "all", "args": "after-used", "ignoreRestSiblings": false }]
}
}
vars
The vars
option has two settings:
-
all
checks all variables for usage, including those in the global scope. This is the default setting. -
local
checks only that locally-declared variables are used but will allow global variables to be unused.
vars: local
Examples of correct code for the { "vars": "local" }
option:
/*eslint no-unused-vars: ["error", { "vars": "local" }]*/
/*global some_unused_var */
some_unused_var = 42;
varsIgnorePattern
The varsIgnorePattern
option specifies exceptions not to check for usage: variables whose names match a regexp pattern. For example, variables whose names contain ignored
or Ignored
.
Examples of correct code for the { "varsIgnorePattern": "[iI]gnored" }
option:
/*eslint no-unused-vars: ["error", { "varsIgnorePattern": "[iI]gnored" }]*/
var firstVarIgnored = 1;
var secondVar = 2;
console.log(secondVar);
args
The args
option has three settings:
-
after-used
- only the last argument must be used. This allows you, for instance, to have two named parameters to a function and as long as you use the second argument, ESLint will not warn you about the first. This is the default setting. -
all
- all named arguments must be used. -
none
- do not check arguments.
args: after-used
Examples of incorrect code for the default { "args": "after-used" }
option:
/*eslint no-unused-vars: ["error", { "args": "after-used" }]*/
// 1 error
// "baz" is defined but never used
(function(foo, bar, baz) {
return bar;
})();
Examples of correct code for the default { "args": "after-used" }
option:
/*eslint no-unused-vars: ["error", {"args": "after-used"}]*/
(function(foo, bar, baz) {
return baz;
})();
args: all
Examples of incorrect code for the { "args": "all" }
option:
/*eslint no-unused-vars: ["error", { "args": "all" }]*/
// 2 errors
// "foo" is defined but never used
// "baz" is defined but never used
(function(foo, bar, baz) {
return bar;
})();
args: none
Examples of correct code for the { "args": "none" }
option:
/*eslint no-unused-vars: ["error", { "args": "none" }]*/
(function(foo, bar, baz) {
return bar;
})();
ignoreRestSiblings
The ignoreRestSiblings
option is a boolean (default: false
). Using a Rest Property it is possible to "omit" properties from an object, but by default the sibling properties are marked as "unused". With this option enabled the rest property's siblings are ignored.
Examples of correct code for the { "ignoreRestSiblings": true }
option:
/*eslint no-unused-vars: ["error", { "ignoreRestSiblings": true }]*/
// 'type' is ignored because it has a rest property sibling.
var { type, ...coords } = data;
argsIgnorePattern
The argsIgnorePattern
option specifies exceptions not to check for usage: arguments whose names match a regexp pattern. For example, variables whose names begin with an underscore.
Examples of correct code for the { "argsIgnorePattern": "^_" }
option:
/*eslint no-unused-vars: ["error", { "argsIgnorePattern": "^_" }]*/
function foo(x, _y) {
return x + 1;
}
foo();
caughtErrors
The caughtErrors
option is used for catch
block arguments validation.
It has two settings:
-
none
- do not check error objects. This is the default setting. -
all
- all named arguments must be used.
caughtErrors: none
Not specifying this rule is equivalent of assigning it to none
.
Examples of correct code for the { "caughtErrors": "none" }
option:
/*eslint no-unused-vars: ["error", { "caughtErrors": "none" }]*/
try {
//...
} catch (err) {
console.error("errors");
}
caughtErrors: all
Examples of incorrect code for the { "caughtErrors": "all" }
option:
/*eslint no-unused-vars: ["error", { "caughtErrors": "all" }]*/
// 1 error
// "err" is defined but never used
try {
//...
} catch (err) {
console.error("errors");
}
caughtErrorsIgnorePattern
The caughtErrorsIgnorePattern
option specifies exceptions not to check for usage: catch arguments whose names match a regexp pattern. For example, variables whose names begin with a string 'ignore'.
Examples of correct code for the { "caughtErrorsIgnorePattern": "^ignore" }
option:
/*eslint no-unused-vars: ["error", { "caughtErrorsIgnorePattern": "^ignore" }]*/
try {
//...
} catch (ignoreErr) {
console.error("errors");
}
When Not To Use It
If you don't want to be notified about unused variables or function arguments, you can safely turn this rule off. Source: http://eslint.org/docs/rules/