Showing 437 of 437 total issues
Use %i
or %I
for an array of symbols. Open
DASHBOARDS = [
:projects,
:users,
]
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- Exclude checks
This cop can check for array literals made up of symbols that are not using the %i() syntax.
Alternatively, it checks for symbol arrays using the %i() syntax on projects which do not want to use that syntax.
Configuration option: MinSize
If set, arrays with fewer elements than this value will not trigger the
cop. For example, a MinSize of
3` will not enforce a style on an array
of 2 or fewer elements.
Example: EnforcedStyle: percent (default)
# good
%i[foo bar baz]
# bad
[:foo, :bar, :baz]
Example: EnforcedStyle: brackets
# good
[:foo, :bar, :baz]
# bad
%i[foo bar baz]
Line is too long. [83/80] Open
# Call 'byebug' anywhere in the code to stop execution and get a debugger console
- Exclude checks
Line is too long. [87/80] Open
# config.i18n.load_path += Dir[Rails.root.join('my', 'locales', '*.{rb,yml}').to_s]
- Exclude checks
Line is too long. [82/80] Open
Rails.application.config.assets.precompile += %w( bootstrap/dist/js/bootstrap.js )
- Exclude checks
'$' is not defined. Open
if ( !$(this).parent().parent().hasClass('target-section') ) {
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- Exclude checks
Disallow Undeclared Variables (no-undef)
This rule can help you locate potential ReferenceErrors resulting from misspellings of variable and parameter names, or accidental implicit globals (for example, from forgetting the var
keyword in a for
loop initializer).
Rule Details
Any reference to an undeclared variable causes a warning, unless the variable is explicitly mentioned in a /*global ...*/
comment.
Examples of incorrect code for this rule:
/*eslint no-undef: "error"*/
var a = someFunction();
b = 10;
Examples of correct code for this rule with global
declaration:
/*global someFunction b:true*/
/*eslint no-undef: "error"*/
var a = someFunction();
b = 10;
The b:true
syntax in /*global */
indicates that assignment to b
is correct.
Examples of incorrect code for this rule with global
declaration:
/*global b*/
/*eslint no-undef: "error"*/
b = 10;
By default, variables declared in /*global */
are read-only, therefore assignment is incorrect.
Options
-
typeof
set to true will warn for variables used inside typeof check (Default false).
typeof
Examples of correct code for the default { "typeof": false }
option:
/*eslint no-undef: "error"*/
if (typeof UndefinedIdentifier === "undefined") {
// do something ...
}
You can use this option if you want to prevent typeof
check on a variable which has not been declared.
Examples of incorrect code for the { "typeof": true }
option:
/*eslint no-undef: ["error", { "typeof": true }] */
if(typeof a === "string"){}
Examples of correct code for the { "typeof": true }
option with global
declaration:
/*global a*/
/*eslint no-undef: ["error", { "typeof": true }] */
if(typeof a === "string"){}
Environments
For convenience, ESLint provides shortcuts that pre-define global variables exposed by popular libraries and runtime environments. This rule supports these environments, as listed in Specifying Environments. A few examples are given below.
browser
Examples of correct code for this rule with browser
environment:
/*eslint no-undef: "error"*/
/*eslint-env browser*/
setTimeout(function() {
alert("Hello");
});
node
Examples of correct code for this rule with node
environment:
/*eslint no-undef: "error"*/
/*eslint-env node*/
var fs = require("fs");
module.exports = function() {
console.log(fs);
};
When Not To Use It
If explicit declaration of global variables is not to your taste.
Compatibility
This rule provides compatibility with treatment of global variables in JSHint and JSLint. Source: http://eslint.org/docs/rules/
Unnecessary semicolon. Open
};
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- Exclude checks
disallow unnecessary semicolons (no-extra-semi)
Typing mistakes and misunderstandings about where semicolons are required can lead to semicolons that are unnecessary. While not technically an error, extra semicolons can cause confusion when reading code.
Rule Details
This rule disallows unnecessary semicolons.
Examples of incorrect code for this rule:
/*eslint no-extra-semi: "error"*/
var x = 5;;
function foo() {
// code
};
Examples of correct code for this rule:
/*eslint no-extra-semi: "error"*/
var x = 5;
var foo = function() {
// code
};
When Not To Use It
If you intentionally use extra semicolons then you can disable this rule.
Related Rules
- [semi](semi.md)
- [semi-spacing](semi-spacing.md) Source: http://eslint.org/docs/rules/
'console' is not defined. Open
console.debug( "Found target anchor: %s", anchor );
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- Exclude checks
Disallow Undeclared Variables (no-undef)
This rule can help you locate potential ReferenceErrors resulting from misspellings of variable and parameter names, or accidental implicit globals (for example, from forgetting the var
keyword in a for
loop initializer).
Rule Details
Any reference to an undeclared variable causes a warning, unless the variable is explicitly mentioned in a /*global ...*/
comment.
Examples of incorrect code for this rule:
/*eslint no-undef: "error"*/
var a = someFunction();
b = 10;
Examples of correct code for this rule with global
declaration:
/*global someFunction b:true*/
/*eslint no-undef: "error"*/
var a = someFunction();
b = 10;
The b:true
syntax in /*global */
indicates that assignment to b
is correct.
Examples of incorrect code for this rule with global
declaration:
/*global b*/
/*eslint no-undef: "error"*/
b = 10;
By default, variables declared in /*global */
are read-only, therefore assignment is incorrect.
Options
-
typeof
set to true will warn for variables used inside typeof check (Default false).
typeof
Examples of correct code for the default { "typeof": false }
option:
/*eslint no-undef: "error"*/
if (typeof UndefinedIdentifier === "undefined") {
// do something ...
}
You can use this option if you want to prevent typeof
check on a variable which has not been declared.
Examples of incorrect code for the { "typeof": true }
option:
/*eslint no-undef: ["error", { "typeof": true }] */
if(typeof a === "string"){}
Examples of correct code for the { "typeof": true }
option with global
declaration:
/*global a*/
/*eslint no-undef: ["error", { "typeof": true }] */
if(typeof a === "string"){}
Environments
For convenience, ESLint provides shortcuts that pre-define global variables exposed by popular libraries and runtime environments. This rule supports these environments, as listed in Specifying Environments. A few examples are given below.
browser
Examples of correct code for this rule with browser
environment:
/*eslint no-undef: "error"*/
/*eslint-env browser*/
setTimeout(function() {
alert("Hello");
});
node
Examples of correct code for this rule with node
environment:
/*eslint no-undef: "error"*/
/*eslint-env node*/
var fs = require("fs");
module.exports = function() {
console.log(fs);
};
When Not To Use It
If explicit declaration of global variables is not to your taste.
Compatibility
This rule provides compatibility with treatment of global variables in JSHint and JSLint. Source: http://eslint.org/docs/rules/
Unnecessary semicolon. Open
};
- Read upRead up
- Exclude checks
disallow unnecessary semicolons (no-extra-semi)
Typing mistakes and misunderstandings about where semicolons are required can lead to semicolons that are unnecessary. While not technically an error, extra semicolons can cause confusion when reading code.
Rule Details
This rule disallows unnecessary semicolons.
Examples of incorrect code for this rule:
/*eslint no-extra-semi: "error"*/
var x = 5;;
function foo() {
// code
};
Examples of correct code for this rule:
/*eslint no-extra-semi: "error"*/
var x = 5;
var foo = function() {
// code
};
When Not To Use It
If you intentionally use extra semicolons then you can disable this rule.
Related Rules
- [semi](semi.md)
- [semi-spacing](semi-spacing.md) Source: http://eslint.org/docs/rules/
'$' is not defined. Open
this.$current = $(target.firstChild);
- Read upRead up
- Exclude checks
Disallow Undeclared Variables (no-undef)
This rule can help you locate potential ReferenceErrors resulting from misspellings of variable and parameter names, or accidental implicit globals (for example, from forgetting the var
keyword in a for
loop initializer).
Rule Details
Any reference to an undeclared variable causes a warning, unless the variable is explicitly mentioned in a /*global ...*/
comment.
Examples of incorrect code for this rule:
/*eslint no-undef: "error"*/
var a = someFunction();
b = 10;
Examples of correct code for this rule with global
declaration:
/*global someFunction b:true*/
/*eslint no-undef: "error"*/
var a = someFunction();
b = 10;
The b:true
syntax in /*global */
indicates that assignment to b
is correct.
Examples of incorrect code for this rule with global
declaration:
/*global b*/
/*eslint no-undef: "error"*/
b = 10;
By default, variables declared in /*global */
are read-only, therefore assignment is incorrect.
Options
-
typeof
set to true will warn for variables used inside typeof check (Default false).
typeof
Examples of correct code for the default { "typeof": false }
option:
/*eslint no-undef: "error"*/
if (typeof UndefinedIdentifier === "undefined") {
// do something ...
}
You can use this option if you want to prevent typeof
check on a variable which has not been declared.
Examples of incorrect code for the { "typeof": true }
option:
/*eslint no-undef: ["error", { "typeof": true }] */
if(typeof a === "string"){}
Examples of correct code for the { "typeof": true }
option with global
declaration:
/*global a*/
/*eslint no-undef: ["error", { "typeof": true }] */
if(typeof a === "string"){}
Environments
For convenience, ESLint provides shortcuts that pre-define global variables exposed by popular libraries and runtime environments. This rule supports these environments, as listed in Specifying Environments. A few examples are given below.
browser
Examples of correct code for this rule with browser
environment:
/*eslint no-undef: "error"*/
/*eslint-env browser*/
setTimeout(function() {
alert("Hello");
});
node
Examples of correct code for this rule with node
environment:
/*eslint no-undef: "error"*/
/*eslint-env node*/
var fs = require("fs");
module.exports = function() {
console.log(fs);
};
When Not To Use It
If explicit declaration of global variables is not to your taste.
Compatibility
This rule provides compatibility with treatment of global variables in JSHint and JSLint. Source: http://eslint.org/docs/rules/
Prefer single-quoted strings when you don't need string interpolation or special symbols. Open
test "should get index" do
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- Exclude checks
Checks if uses of quotes match the configured preference.
Example: EnforcedStyle: single_quotes (default)
# bad
"No special symbols"
"No string interpolation"
"Just text"
# good
'No special symbols'
'No string interpolation'
'Just text'
"Wait! What's #{this}!"
Example: EnforcedStyle: double_quotes
# bad
'Just some text'
'No special chars or interpolation'
# good
"Just some text"
"No special chars or interpolation"
"Every string in #{project} uses double_quotes"
Space inside } missing. Open
DatabaseCleaner.strategy = :truncation, {only: %w( meetup_events )}
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- Exclude checks
Checks that braces used for hash literals have or don't have surrounding space depending on configuration.
Example: EnforcedStyle: space
# The `space` style enforces that hash literals have
# surrounding space.
# bad
h = {a: 1, b: 2}
# good
h = { a: 1, b: 2 }
Example: EnforcedStyle: no_space
# The `no_space` style enforces that hash literals have
# no surrounding space.
# bad
h = { a: 1, b: 2 }
# good
h = {a: 1, b: 2}
Example: EnforcedStyle: compact
# The `compact` style normally requires a space inside
# hash braces, with the exception that successive left
# braces or right braces are collapsed together in nested hashes.
# bad
h = { a: { b: 2 } }
# good
h = { a: { b: 2 }}
Do not use spaces inside percent literal delimiters. Open
DatabaseCleaner.strategy = :truncation, {only: %w( meetup_events )}
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- Exclude checks
Checks for unnecessary additional spaces inside the delimiters of %i/%w/%x literals.
Example:
# good
%i(foo bar baz)
# bad
%w( foo bar baz )
# bad
%x( ls -l )
Add an empty line after magic comments. Open
require 'meetup_client'
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- Exclude checks
Checks for a newline after the final magic comment.
Example:
# good
# frozen_string_literal: true
# Some documentation for Person
class Person
# Some code
end
# bad
# frozen_string_literal: true
# Some documentation for Person
class Person
# Some code
end
Use 2 spaces for indentation in a hash, relative to the first position after the preceding left parenthesis. Open
group_urlname: @meetup_url_name,
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- Exclude checks
This cops checks the indentation of the first key in a hash literal where the opening brace and the first key are on separate lines. The other keys' indentations are handled by the AlignHash cop.
By default, Hash literals that are arguments in a method call with parentheses, and where the opening curly brace of the hash is on the same line as the opening parenthesis of the method call, shall have their first key indented one step (two spaces) more than the position inside the opening parenthesis.
Other hash literals shall have their first key indented one step more than the start of the line where the opening curly brace is.
This default style is called 'specialinsideparentheses'. Alternative styles are 'consistent' and 'align_braces'. Here are examples:
Example: EnforcedStyle: specialinsideparentheses (default)
# The `special_inside_parentheses` style enforces that the first key
# in a hash literal where the opening brace and the first key are on
# separate lines is indented one step (two spaces) more than the
# position inside the opening parentheses.
# bad
hash = {
key: :value
}
and_in_a_method_call({
no: :difference
})
# good
special_inside_parentheses
hash = {
key: :value
}
but_in_a_method_call({
its_like: :this
})
Example: EnforcedStyle: consistent
# The `consistent` style enforces that the first key in a hash
# literal where the opening brace and the first key are on
# seprate lines is indented the same as a hash literal which is not
# defined inside a method call.
# bad
hash = {
key: :value
}
but_in_a_method_call({
its_like: :this
})
# good
hash = {
key: :value
}
and_in_a_method_call({
no: :difference
})
Example: EnforcedStyle: align_braces
# The `align_brackets` style enforces that the opening and closing
# braces are indented to the same position.
# bad
and_now_for_something = {
completely: :different
}
# good
and_now_for_something = {
completely: :different
}
Use the new Ruby 1.9 hash syntax. Open
task :perform_now => :environment do
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- Exclude checks
This cop checks hash literal syntax.
It can enforce either the use of the class hash rocket syntax or the use of the newer Ruby 1.9 syntax (when applicable).
A separate offense is registered for each problematic pair.
The supported styles are:
- ruby19 - forces use of the 1.9 syntax (e.g.
{a: 1}
) when hashes have all symbols for keys - hash_rockets - forces use of hash rockets for all hashes
- nomixedkeys - simply checks for hashes with mixed syntaxes
- ruby19nomixed_keys - forces use of ruby 1.9 syntax and forbids mixed syntax hashes
Example: EnforcedStyle: ruby19 (default)
# bad
{:a => 2}
{b: 1, :c => 2}
# good
{a: 2, b: 1}
{:c => 2, 'd' => 2} # acceptable since 'd' isn't a symbol
{d: 1, 'e' => 2} # technically not forbidden
Example: EnforcedStyle: hash_rockets
# bad
{a: 1, b: 2}
{c: 1, 'd' => 5}
# good
{:a => 1, :b => 2}
Example: EnforcedStyle: nomixedkeys
# bad
{:a => 1, b: 2}
{c: 1, 'd' => 2}
# good
{:a => 1, :b => 2}
{c: 1, d: 2}
Example: EnforcedStyle: ruby19nomixed_keys
# bad
{:a => 1, :b => 2}
{c: 2, 'd' => 3} # should just use hash rockets
# good
{a: 1, b: 2}
{:c => 3, 'd' => 4}
Gems should be sorted in an alphabetical order within their section of the Gemfile. Gem config
should appear before meetup_client
. Open
gem 'config'
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- Exclude checks
Gems should be alphabetically sorted within groups.
Example:
# bad
gem 'rubocop'
gem 'rspec'
# good
gem 'rspec'
gem 'rubocop'
# good
gem 'rubocop'
gem 'rspec'
# good only if TreatCommentsAsGroupSeparators is true
# For code quality
gem 'rubocop'
# For tests
gem 'rspec'
Extra blank line detected. Open
# Bundle edge Rails instead: gem 'rails', github: 'rails/rails'
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- Exclude checks
This cops checks for two or more consecutive blank lines.
Example:
# bad - It has two empty lines.
some_method
# one empty line
# two empty lines
some_method
# good
some_method
# one empty line
some_method
Prefer single-quoted strings when you don't need string interpolation or special symbols. Open
config.const_name = "Settings"
- Read upRead up
- Exclude checks
Checks if uses of quotes match the configured preference.
Example: EnforcedStyle: single_quotes (default)
# bad
"No special symbols"
"No string interpolation"
"Just text"
# good
'No special symbols'
'No string interpolation'
'Just text'
"Wait! What's #{this}!"
Example: EnforcedStyle: double_quotes
# bad
'Just some text'
'No special chars or interpolation'
# good
"Just some text"
"No special chars or interpolation"
"Every string in #{project} uses double_quotes"
'Search' is not defined. Open
Search.prototype = $.extend({}, Navigation, new function() {
- Read upRead up
- Exclude checks
Disallow Undeclared Variables (no-undef)
This rule can help you locate potential ReferenceErrors resulting from misspellings of variable and parameter names, or accidental implicit globals (for example, from forgetting the var
keyword in a for
loop initializer).
Rule Details
Any reference to an undeclared variable causes a warning, unless the variable is explicitly mentioned in a /*global ...*/
comment.
Examples of incorrect code for this rule:
/*eslint no-undef: "error"*/
var a = someFunction();
b = 10;
Examples of correct code for this rule with global
declaration:
/*global someFunction b:true*/
/*eslint no-undef: "error"*/
var a = someFunction();
b = 10;
The b:true
syntax in /*global */
indicates that assignment to b
is correct.
Examples of incorrect code for this rule with global
declaration:
/*global b*/
/*eslint no-undef: "error"*/
b = 10;
By default, variables declared in /*global */
are read-only, therefore assignment is incorrect.
Options
-
typeof
set to true will warn for variables used inside typeof check (Default false).
typeof
Examples of correct code for the default { "typeof": false }
option:
/*eslint no-undef: "error"*/
if (typeof UndefinedIdentifier === "undefined") {
// do something ...
}
You can use this option if you want to prevent typeof
check on a variable which has not been declared.
Examples of incorrect code for the { "typeof": true }
option:
/*eslint no-undef: ["error", { "typeof": true }] */
if(typeof a === "string"){}
Examples of correct code for the { "typeof": true }
option with global
declaration:
/*global a*/
/*eslint no-undef: ["error", { "typeof": true }] */
if(typeof a === "string"){}
Environments
For convenience, ESLint provides shortcuts that pre-define global variables exposed by popular libraries and runtime environments. This rule supports these environments, as listed in Specifying Environments. A few examples are given below.
browser
Examples of correct code for this rule with browser
environment:
/*eslint no-undef: "error"*/
/*eslint-env browser*/
setTimeout(function() {
alert("Hello");
});
node
Examples of correct code for this rule with node
environment:
/*eslint no-undef: "error"*/
/*eslint-env node*/
var fs = require("fs");
module.exports = function() {
console.log(fs);
};
When Not To Use It
If explicit declaration of global variables is not to your taste.
Compatibility
This rule provides compatibility with treatment of global variables in JSHint and JSLint. Source: http://eslint.org/docs/rules/
Freeze mutable objects assigned to constants. Open
COLLECTION_ATTRIBUTES = [
:project,
:id,
:created_at,
:updated_at,
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- Exclude checks
This cop checks whether some constant value isn't a mutable literal (e.g. array or hash).
Example:
# bad
CONST = [1, 2, 3]
# good
CONST = [1, 2, 3].freeze