Useless constructor. Open
constructor (props) {
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Disallow unnecessary constructor (no-useless-constructor)
ES2015 provides a default class constructor if one is not specified. As such, it is unnecessary to provide an empty constructor or one that simply delegates into its parent class, as in the following examples:
class A {
constructor () {
}
}
class A extends B {
constructor (value) {
super(value);
}
}
Rule Details
This rule flags class constructors that can be safely removed without changing how the class works.
Examples
Examples of incorrect code for this rule:
/*eslint no-useless-constructor: "error"*/
/*eslint-env es6*/
class A {
constructor () {
}
}
class A extends B {
constructor (...args) {
super(...args);
}
}
Examples of correct code for this rule:
/*eslint no-useless-constructor: "error"*/
class A { }
class A {
constructor () {
doSomething();
}
}
class A extends B {
constructor() {
super('foo');
}
}
class A extends B {
constructor() {
super();
doSomething();
}
}
When Not To Use It
If you don't want to be notified about unnecessary constructors, you can safely disable this rule. Source: http://eslint.org/docs/rules/
Strings must use singlequote. Open
activeClassName={"active"} />
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enforce the consistent use of either backticks, double, or single quotes (quotes)
JavaScript allows you to define strings in one of three ways: double quotes, single quotes, and backticks (as of ECMAScript 6). For example:
/*eslint-env es6*/
var double = "double";
var single = 'single';
var backtick = `backtick`; // ES6 only
Each of these lines creates a string and, in some cases, can be used interchangeably. The choice of how to define strings in a codebase is a stylistic one outside of template literals (which allow embedded of expressions to be interpreted).
Many codebases require strings to be defined in a consistent manner.
Rule Details
This rule enforces the consistent use of either backticks, double, or single quotes.
Options
This rule has two options, a string option and an object option.
String option:
-
"double"
(default) requires the use of double quotes wherever possible -
"single"
requires the use of single quotes wherever possible -
"backtick"
requires the use of backticks wherever possible
Object option:
-
"avoidEscape": true
allows strings to use single-quotes or double-quotes so long as the string contains a quote that would have to be escaped otherwise -
"allowTemplateLiterals": true
allows strings to use backticks
Deprecated: The object property avoid-escape
is deprecated; please use the object property avoidEscape
instead.
double
Examples of incorrect code for this rule with the default "double"
option:
/*eslint quotes: ["error", "double"]*/
var single = 'single';
var unescaped = 'a string containing "double" quotes';
Examples of correct code for this rule with the default "double"
option:
/*eslint quotes: ["error", "double"]*/
/*eslint-env es6*/
var double = "double";
var backtick = `back\ntick`; // backticks are allowed due to newline
var backtick = tag`backtick`; // backticks are allowed due to tag
single
Examples of incorrect code for this rule with the "single"
option:
/*eslint quotes: ["error", "single"]*/
var double = "double";
var unescaped = "a string containing 'single' quotes";
Examples of correct code for this rule with the "single"
option:
/*eslint quotes: ["error", "single"]*/
/*eslint-env es6*/
var single = 'single';
var backtick = `back${x}tick`; // backticks are allowed due to substitution
backticks
Examples of incorrect code for this rule with the "backtick"
option:
/*eslint quotes: ["error", "backtick"]*/
var single = 'single';
var double = "double";
var unescaped = 'a string containing `backticks`';
Examples of correct code for this rule with the "backtick"
option:
/*eslint quotes: ["error", "backtick"]*/
/*eslint-env es6*/
var backtick = `backtick`;
avoidEscape
Examples of additional correct code for this rule with the "double", { "avoidEscape": true }
options:
/*eslint quotes: ["error", "double", { "avoidEscape": true }]*/
var single = 'a string containing "double" quotes';
Examples of additional correct code for this rule with the "single", { "avoidEscape": true }
options:
/*eslint quotes: ["error", "single", { "avoidEscape": true }]*/
var double = "a string containing 'single' quotes";
Examples of additional correct code for this rule with the "backtick", { "avoidEscape": true }
options:
/*eslint quotes: ["error", "backtick", { "avoidEscape": true }]*/
var double = "a string containing `backtick` quotes"
allowTemplateLiterals
Examples of additional correct code for this rule with the "double", { "allowTemplateLiterals": true }
options:
/*eslint quotes: ["error", "double", { "allowTemplateLiterals": true }]*/
var double = "double";
var double = `double`;
Examples of additional correct code for this rule with the "single", { "allowTemplateLiterals": true }
options:
/*eslint quotes: ["error", "single", { "allowTemplateLiterals": true }]*/
var single = 'single';
var single = `single`;
When Not To Use It
If you do not need consistency in your string styles, you can safely disable this rule. Source: http://eslint.org/docs/rules/
The closing bracket must be aligned with the line containing the opening tag (expected column 7 on the next line) Open
activeClassName={"active"} />
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For more information visit Source: http://eslint.org/docs/rules/
JSX not allowed in files with extension '.js' Open
<ReactPaginate
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For more information visit Source: http://eslint.org/docs/rules/
Empty components are self-closing Open
nextLabel={<i className="right chevron icon"></i>}
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For more information visit Source: http://eslint.org/docs/rules/
Prop type object
is forbidden Open
collect: PropTypes.object.isRequired,
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For more information visit Source: http://eslint.org/docs/rules/
Empty components are self-closing Open
previousLabel={<i className="left chevron icon"></i>}
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For more information visit Source: http://eslint.org/docs/rules/