Missing space after *. Open
create: [ RestAuth, function *(next) {
- Read upRead up
- Exclude checks
Enforce spacing around the * in generator functions (generator-star-spacing)
Generators are a new type of function in ECMAScript 6 that can return multiple values over time.
These special functions are indicated by placing an *
after the function
keyword.
Here is an example of a generator function:
/*eslint-env es6*/
function* generator() {
yield "44";
yield "55";
}
This is also valid:
/*eslint-env es6*/
function *generator() {
yield "44";
yield "55";
}
This is valid as well:
/*eslint-env es6*/
function * generator() {
yield "44";
yield "55";
}
To keep a sense of consistency when using generators this rule enforces a single position for the *
.
Rule Details
This rule aims to enforce spacing around the *
of generator functions.
Options
The rule takes one option, an object, which has two keys before
and after
having boolean values true
or false
.
-
before
enforces spacing between the*
and thefunction
keyword. If it istrue
, a space is required, otherwise spaces are disallowed.
In object literal shorthand methods, spacing before the *
is not checked, as they lack a function
keyword.
-
after
enforces spacing between the*
and the function name (or the opening parenthesis for anonymous generator functions). If it istrue
, a space is required, otherwise spaces are disallowed.
The default is {"before": true, "after": false}
.
An example configuration:
"generator-star-spacing": ["error", {"before": true, "after": false}]
And the option has shorthand as a string keyword:
-
{"before": true, "after": false}
→"before"
-
{"before": false, "after": true}
→"after"
-
{"before": true, "after": true}
→"both"
-
{"before": false, "after": false}
→"neither"
An example of shorthand configuration:
"generator-star-spacing": ["error", "after"]
Examples
before
Examples of correct code for this rule with the "before"
option:
/*eslint generator-star-spacing: ["error", {"before": true, "after": false}]*/
/*eslint-env es6*/
function *generator() {}
var anonymous = function *() {};
var shorthand = { *generator() {} };
after
Examples of correct code for this rule with the "after"
option:
/*eslint generator-star-spacing: ["error", {"before": false, "after": true}]*/
/*eslint-env es6*/
function* generator() {}
var anonymous = function* () {};
var shorthand = { * generator() {} };
both
Examples of correct code for this rule with the "both"
option:
/*eslint generator-star-spacing: ["error", {"before": true, "after": true}]*/
/*eslint-env es6*/
function * generator() {}
var anonymous = function * () {};
var shorthand = { * generator() {} };
neither
Examples of correct code for this rule with the "neither"
option:
/*eslint generator-star-spacing: ["error", {"before": false, "after": false}]*/
/*eslint-env es6*/
function*generator() {}
var anonymous = function*() {};
var shorthand = { *generator() {} };
When Not To Use It
If your project will not be using generators or you are not concerned with spacing consistency, you do not need this rule.
Further Reading
Unexpected space before *. Open
update: [ RestAuth, function *(next) {
- Read upRead up
- Exclude checks
Enforce spacing around the * in generator functions (generator-star-spacing)
Generators are a new type of function in ECMAScript 6 that can return multiple values over time.
These special functions are indicated by placing an *
after the function
keyword.
Here is an example of a generator function:
/*eslint-env es6*/
function* generator() {
yield "44";
yield "55";
}
This is also valid:
/*eslint-env es6*/
function *generator() {
yield "44";
yield "55";
}
This is valid as well:
/*eslint-env es6*/
function * generator() {
yield "44";
yield "55";
}
To keep a sense of consistency when using generators this rule enforces a single position for the *
.
Rule Details
This rule aims to enforce spacing around the *
of generator functions.
Options
The rule takes one option, an object, which has two keys before
and after
having boolean values true
or false
.
-
before
enforces spacing between the*
and thefunction
keyword. If it istrue
, a space is required, otherwise spaces are disallowed.
In object literal shorthand methods, spacing before the *
is not checked, as they lack a function
keyword.
-
after
enforces spacing between the*
and the function name (or the opening parenthesis for anonymous generator functions). If it istrue
, a space is required, otherwise spaces are disallowed.
The default is {"before": true, "after": false}
.
An example configuration:
"generator-star-spacing": ["error", {"before": true, "after": false}]
And the option has shorthand as a string keyword:
-
{"before": true, "after": false}
→"before"
-
{"before": false, "after": true}
→"after"
-
{"before": true, "after": true}
→"both"
-
{"before": false, "after": false}
→"neither"
An example of shorthand configuration:
"generator-star-spacing": ["error", "after"]
Examples
before
Examples of correct code for this rule with the "before"
option:
/*eslint generator-star-spacing: ["error", {"before": true, "after": false}]*/
/*eslint-env es6*/
function *generator() {}
var anonymous = function *() {};
var shorthand = { *generator() {} };
after
Examples of correct code for this rule with the "after"
option:
/*eslint generator-star-spacing: ["error", {"before": false, "after": true}]*/
/*eslint-env es6*/
function* generator() {}
var anonymous = function* () {};
var shorthand = { * generator() {} };
both
Examples of correct code for this rule with the "both"
option:
/*eslint generator-star-spacing: ["error", {"before": true, "after": true}]*/
/*eslint-env es6*/
function * generator() {}
var anonymous = function * () {};
var shorthand = { * generator() {} };
neither
Examples of correct code for this rule with the "neither"
option:
/*eslint generator-star-spacing: ["error", {"before": false, "after": false}]*/
/*eslint-env es6*/
function*generator() {}
var anonymous = function*() {};
var shorthand = { *generator() {} };
When Not To Use It
If your project will not be using generators or you are not concerned with spacing consistency, you do not need this rule.
Further Reading
Unexpected space before *. Open
index: [ RestAuth, function *(next) {
- Read upRead up
- Exclude checks
Enforce spacing around the * in generator functions (generator-star-spacing)
Generators are a new type of function in ECMAScript 6 that can return multiple values over time.
These special functions are indicated by placing an *
after the function
keyword.
Here is an example of a generator function:
/*eslint-env es6*/
function* generator() {
yield "44";
yield "55";
}
This is also valid:
/*eslint-env es6*/
function *generator() {
yield "44";
yield "55";
}
This is valid as well:
/*eslint-env es6*/
function * generator() {
yield "44";
yield "55";
}
To keep a sense of consistency when using generators this rule enforces a single position for the *
.
Rule Details
This rule aims to enforce spacing around the *
of generator functions.
Options
The rule takes one option, an object, which has two keys before
and after
having boolean values true
or false
.
-
before
enforces spacing between the*
and thefunction
keyword. If it istrue
, a space is required, otherwise spaces are disallowed.
In object literal shorthand methods, spacing before the *
is not checked, as they lack a function
keyword.
-
after
enforces spacing between the*
and the function name (or the opening parenthesis for anonymous generator functions). If it istrue
, a space is required, otherwise spaces are disallowed.
The default is {"before": true, "after": false}
.
An example configuration:
"generator-star-spacing": ["error", {"before": true, "after": false}]
And the option has shorthand as a string keyword:
-
{"before": true, "after": false}
→"before"
-
{"before": false, "after": true}
→"after"
-
{"before": true, "after": true}
→"both"
-
{"before": false, "after": false}
→"neither"
An example of shorthand configuration:
"generator-star-spacing": ["error", "after"]
Examples
before
Examples of correct code for this rule with the "before"
option:
/*eslint generator-star-spacing: ["error", {"before": true, "after": false}]*/
/*eslint-env es6*/
function *generator() {}
var anonymous = function *() {};
var shorthand = { *generator() {} };
after
Examples of correct code for this rule with the "after"
option:
/*eslint generator-star-spacing: ["error", {"before": false, "after": true}]*/
/*eslint-env es6*/
function* generator() {}
var anonymous = function* () {};
var shorthand = { * generator() {} };
both
Examples of correct code for this rule with the "both"
option:
/*eslint generator-star-spacing: ["error", {"before": true, "after": true}]*/
/*eslint-env es6*/
function * generator() {}
var anonymous = function * () {};
var shorthand = { * generator() {} };
neither
Examples of correct code for this rule with the "neither"
option:
/*eslint generator-star-spacing: ["error", {"before": false, "after": false}]*/
/*eslint-env es6*/
function*generator() {}
var anonymous = function*() {};
var shorthand = { *generator() {} };
When Not To Use It
If your project will not be using generators or you are not concerned with spacing consistency, you do not need this rule.
Further Reading
Missing space after *. Open
edit: function *(next) {
- Read upRead up
- Exclude checks
Enforce spacing around the * in generator functions (generator-star-spacing)
Generators are a new type of function in ECMAScript 6 that can return multiple values over time.
These special functions are indicated by placing an *
after the function
keyword.
Here is an example of a generator function:
/*eslint-env es6*/
function* generator() {
yield "44";
yield "55";
}
This is also valid:
/*eslint-env es6*/
function *generator() {
yield "44";
yield "55";
}
This is valid as well:
/*eslint-env es6*/
function * generator() {
yield "44";
yield "55";
}
To keep a sense of consistency when using generators this rule enforces a single position for the *
.
Rule Details
This rule aims to enforce spacing around the *
of generator functions.
Options
The rule takes one option, an object, which has two keys before
and after
having boolean values true
or false
.
-
before
enforces spacing between the*
and thefunction
keyword. If it istrue
, a space is required, otherwise spaces are disallowed.
In object literal shorthand methods, spacing before the *
is not checked, as they lack a function
keyword.
-
after
enforces spacing between the*
and the function name (or the opening parenthesis for anonymous generator functions). If it istrue
, a space is required, otherwise spaces are disallowed.
The default is {"before": true, "after": false}
.
An example configuration:
"generator-star-spacing": ["error", {"before": true, "after": false}]
And the option has shorthand as a string keyword:
-
{"before": true, "after": false}
→"before"
-
{"before": false, "after": true}
→"after"
-
{"before": true, "after": true}
→"both"
-
{"before": false, "after": false}
→"neither"
An example of shorthand configuration:
"generator-star-spacing": ["error", "after"]
Examples
before
Examples of correct code for this rule with the "before"
option:
/*eslint generator-star-spacing: ["error", {"before": true, "after": false}]*/
/*eslint-env es6*/
function *generator() {}
var anonymous = function *() {};
var shorthand = { *generator() {} };
after
Examples of correct code for this rule with the "after"
option:
/*eslint generator-star-spacing: ["error", {"before": false, "after": true}]*/
/*eslint-env es6*/
function* generator() {}
var anonymous = function* () {};
var shorthand = { * generator() {} };
both
Examples of correct code for this rule with the "both"
option:
/*eslint generator-star-spacing: ["error", {"before": true, "after": true}]*/
/*eslint-env es6*/
function * generator() {}
var anonymous = function * () {};
var shorthand = { * generator() {} };
neither
Examples of correct code for this rule with the "neither"
option:
/*eslint generator-star-spacing: ["error", {"before": false, "after": false}]*/
/*eslint-env es6*/
function*generator() {}
var anonymous = function*() {};
var shorthand = { *generator() {} };
When Not To Use It
If your project will not be using generators or you are not concerned with spacing consistency, you do not need this rule.
Further Reading
Missing space after *. Open
destroy: [ RestAuth, function *(next) {
- Read upRead up
- Exclude checks
Enforce spacing around the * in generator functions (generator-star-spacing)
Generators are a new type of function in ECMAScript 6 that can return multiple values over time.
These special functions are indicated by placing an *
after the function
keyword.
Here is an example of a generator function:
/*eslint-env es6*/
function* generator() {
yield "44";
yield "55";
}
This is also valid:
/*eslint-env es6*/
function *generator() {
yield "44";
yield "55";
}
This is valid as well:
/*eslint-env es6*/
function * generator() {
yield "44";
yield "55";
}
To keep a sense of consistency when using generators this rule enforces a single position for the *
.
Rule Details
This rule aims to enforce spacing around the *
of generator functions.
Options
The rule takes one option, an object, which has two keys before
and after
having boolean values true
or false
.
-
before
enforces spacing between the*
and thefunction
keyword. If it istrue
, a space is required, otherwise spaces are disallowed.
In object literal shorthand methods, spacing before the *
is not checked, as they lack a function
keyword.
-
after
enforces spacing between the*
and the function name (or the opening parenthesis for anonymous generator functions). If it istrue
, a space is required, otherwise spaces are disallowed.
The default is {"before": true, "after": false}
.
An example configuration:
"generator-star-spacing": ["error", {"before": true, "after": false}]
And the option has shorthand as a string keyword:
-
{"before": true, "after": false}
→"before"
-
{"before": false, "after": true}
→"after"
-
{"before": true, "after": true}
→"both"
-
{"before": false, "after": false}
→"neither"
An example of shorthand configuration:
"generator-star-spacing": ["error", "after"]
Examples
before
Examples of correct code for this rule with the "before"
option:
/*eslint generator-star-spacing: ["error", {"before": true, "after": false}]*/
/*eslint-env es6*/
function *generator() {}
var anonymous = function *() {};
var shorthand = { *generator() {} };
after
Examples of correct code for this rule with the "after"
option:
/*eslint generator-star-spacing: ["error", {"before": false, "after": true}]*/
/*eslint-env es6*/
function* generator() {}
var anonymous = function* () {};
var shorthand = { * generator() {} };
both
Examples of correct code for this rule with the "both"
option:
/*eslint generator-star-spacing: ["error", {"before": true, "after": true}]*/
/*eslint-env es6*/
function * generator() {}
var anonymous = function * () {};
var shorthand = { * generator() {} };
neither
Examples of correct code for this rule with the "neither"
option:
/*eslint generator-star-spacing: ["error", {"before": false, "after": false}]*/
/*eslint-env es6*/
function*generator() {}
var anonymous = function*() {};
var shorthand = { *generator() {} };
When Not To Use It
If your project will not be using generators or you are not concerned with spacing consistency, you do not need this rule.
Further Reading
Missing space after *. Open
index: [ RestAuth, function *(next) {
- Read upRead up
- Exclude checks
Enforce spacing around the * in generator functions (generator-star-spacing)
Generators are a new type of function in ECMAScript 6 that can return multiple values over time.
These special functions are indicated by placing an *
after the function
keyword.
Here is an example of a generator function:
/*eslint-env es6*/
function* generator() {
yield "44";
yield "55";
}
This is also valid:
/*eslint-env es6*/
function *generator() {
yield "44";
yield "55";
}
This is valid as well:
/*eslint-env es6*/
function * generator() {
yield "44";
yield "55";
}
To keep a sense of consistency when using generators this rule enforces a single position for the *
.
Rule Details
This rule aims to enforce spacing around the *
of generator functions.
Options
The rule takes one option, an object, which has two keys before
and after
having boolean values true
or false
.
-
before
enforces spacing between the*
and thefunction
keyword. If it istrue
, a space is required, otherwise spaces are disallowed.
In object literal shorthand methods, spacing before the *
is not checked, as they lack a function
keyword.
-
after
enforces spacing between the*
and the function name (or the opening parenthesis for anonymous generator functions). If it istrue
, a space is required, otherwise spaces are disallowed.
The default is {"before": true, "after": false}
.
An example configuration:
"generator-star-spacing": ["error", {"before": true, "after": false}]
And the option has shorthand as a string keyword:
-
{"before": true, "after": false}
→"before"
-
{"before": false, "after": true}
→"after"
-
{"before": true, "after": true}
→"both"
-
{"before": false, "after": false}
→"neither"
An example of shorthand configuration:
"generator-star-spacing": ["error", "after"]
Examples
before
Examples of correct code for this rule with the "before"
option:
/*eslint generator-star-spacing: ["error", {"before": true, "after": false}]*/
/*eslint-env es6*/
function *generator() {}
var anonymous = function *() {};
var shorthand = { *generator() {} };
after
Examples of correct code for this rule with the "after"
option:
/*eslint generator-star-spacing: ["error", {"before": false, "after": true}]*/
/*eslint-env es6*/
function* generator() {}
var anonymous = function* () {};
var shorthand = { * generator() {} };
both
Examples of correct code for this rule with the "both"
option:
/*eslint generator-star-spacing: ["error", {"before": true, "after": true}]*/
/*eslint-env es6*/
function * generator() {}
var anonymous = function * () {};
var shorthand = { * generator() {} };
neither
Examples of correct code for this rule with the "neither"
option:
/*eslint generator-star-spacing: ["error", {"before": false, "after": false}]*/
/*eslint-env es6*/
function*generator() {}
var anonymous = function*() {};
var shorthand = { *generator() {} };
When Not To Use It
If your project will not be using generators or you are not concerned with spacing consistency, you do not need this rule.
Further Reading
Expected property shorthand. Open
this.body = { errors: errors }
- Read upRead up
- Exclude checks
Require Object Literal Shorthand Syntax (object-shorthand)
EcmaScript 6 provides a concise form for defining object literal methods and properties. This syntax can make defining complex object literals much cleaner.
Here are a few common examples using the ES5 syntax:
// properties
var foo = {
x: x,
y: y,
z: z,
};
// methods
var foo = {
a: function() {},
b: function() {}
};
Now here are ES6 equivalents:
/*eslint-env es6*/
// properties
var foo = {x, y, z};
// methods
var foo = {
a() {},
b() {}
};
Rule Details
This rule enforces the use of the shorthand syntax. This applies to all methods (including generators) defined in object literals and any properties defined where the key name matches name of the assigned variable.
Each of the following properties would warn:
/*eslint object-shorthand: "error"*/
/*eslint-env es6*/
var foo = {
w: function() {},
x: function *() {},
[y]: function() {},
z: z
};
In that case the expected syntax would have been:
/*eslint object-shorthand: "error"*/
/*eslint-env es6*/
var foo = {
w() {},
*x() {},
[y]() {},
z
};
This rule does not flag arrow functions inside of object literals. The following will not warn:
/*eslint object-shorthand: "error"*/
/*eslint-env es6*/
var foo = {
x: (y) => y
};
Options
The rule takes an option which specifies when it should be applied. It can be set to one of the following values:
-
"always"
(default) expects that the shorthand will be used whenever possible. -
"methods"
ensures the method shorthand is used (also applies to generators). -
"properties"
ensures the property shorthand is used (where the key and variable name match). -
"never"
ensures that no property or method shorthand is used in any object literal. -
"consistent"
ensures that either all shorthand or all longform will be used in an object literal. -
"consistent-as-needed"
ensures that either all shorthand or all longform will be used in an object literal, but ensures all shorthand whenever possible.
You can set the option in configuration like this:
{
"object-shorthand": ["error", "always"]
}
Additionally, the rule takes an optional object configuration:
-
"avoidQuotes": true
indicates that longform syntax is preferred whenever the object key is a string literal (default:false
). Note that this option can only be enabled when the string option is set to"always"
,"methods"
, or"properties"
. -
"ignoreConstructors": true
can be used to prevent the rule from reporting errors for constructor functions. (By default, the rule treats constructors the same way as other functions.) Note that this option can only be enabled when the string option is set to"always"
or"methods"
. -
"avoidExplicitReturnArrows": true
indicates that methods are preferred over explicit-return arrow functions for function properties. (By default, the rule allows either of these.) Note that this option can only be enabled when the string option is set to"always"
or"methods"
.
avoidQuotes
{
"object-shorthand": ["error", "always", { "avoidQuotes": true }]
}
Example of incorrect code for this rule with the "always", { "avoidQuotes": true }
option:
/*eslint object-shorthand: ["error", "always", { "avoidQuotes": true }]*/
/*eslint-env es6*/
var foo = {
"bar-baz"() {}
};
Example of correct code for this rule with the "always", { "avoidQuotes": true }
option:
/*eslint object-shorthand: ["error", "always", { "avoidQuotes": true }]*/
/*eslint-env es6*/
var foo = {
"bar-baz": function() {},
"qux": qux
};
ignoreConstructors
{
"object-shorthand": ["error", "always", { "ignoreConstructors": true }]
}
Example of correct code for this rule with the "always", { "ignoreConstructors": true }
option:
/*eslint object-shorthand: ["error", "always", { "ignoreConstructors": true }]*/
/*eslint-env es6*/
var foo = {
ConstructorFunction: function() {}
};
avoidExplicitReturnArrows
{
"object-shorthand": ["error", "always", { "avoidExplicitReturnArrows": true }]
}
Example of incorrect code for this rule with the "always", { "avoidExplicitReturnArrows": true }
option:
/*eslint object-shorthand: ["error", "always", { "avoidExplicitReturnArrows": true }]*/
/*eslint-env es6*/
var foo = {
foo: (bar, baz) => {
return bar + baz;
},
qux: (foobar) => {
return foobar * 2;
}
};
Example of correct code for this rule with the "always", { "avoidExplicitReturnArrows": true }
option:
/*eslint object-shorthand: ["error", "always", { "avoidExplicitReturnArrows": true }]*/
/*eslint-env es6*/
var foo = {
foo(bar, baz) {
return bar + baz;
},
qux: foobar => foobar * 2
};
Example of incorrect code for this rule with the "consistent"
option:
/*eslint object-shorthand: [2, "consistent"]*/
/*eslint-env es6*/
var foo = {
a,
b: "foo",
};
Examples of correct code for this rule with the "consistent"
option:
/*eslint object-shorthand: [2, "consistent"]*/
/*eslint-env es6*/
var foo = {
a: a,
b: "foo"
};
var bar = {
a,
b,
};
Example of incorrect code with the "consistent-as-needed"
option, which is very similar to "consistent"
:
/*eslint object-shorthand: [2, "consistent-as-needed"]*/
/*eslint-env es6*/
var foo = {
a: a,
b: b,
};
When Not To Use It
Anyone not yet in an ES6 environment would not want to apply this rule. Others may find the terseness of the shorthand syntax harder to read and may not want to encourage it with this rule.
Further Reading
Object initializer - MDN Source: http://eslint.org/docs/rules/
Missing space after *. Open
show: [ RestAuth, function *(next) {
- Read upRead up
- Exclude checks
Enforce spacing around the * in generator functions (generator-star-spacing)
Generators are a new type of function in ECMAScript 6 that can return multiple values over time.
These special functions are indicated by placing an *
after the function
keyword.
Here is an example of a generator function:
/*eslint-env es6*/
function* generator() {
yield "44";
yield "55";
}
This is also valid:
/*eslint-env es6*/
function *generator() {
yield "44";
yield "55";
}
This is valid as well:
/*eslint-env es6*/
function * generator() {
yield "44";
yield "55";
}
To keep a sense of consistency when using generators this rule enforces a single position for the *
.
Rule Details
This rule aims to enforce spacing around the *
of generator functions.
Options
The rule takes one option, an object, which has two keys before
and after
having boolean values true
or false
.
-
before
enforces spacing between the*
and thefunction
keyword. If it istrue
, a space is required, otherwise spaces are disallowed.
In object literal shorthand methods, spacing before the *
is not checked, as they lack a function
keyword.
-
after
enforces spacing between the*
and the function name (or the opening parenthesis for anonymous generator functions). If it istrue
, a space is required, otherwise spaces are disallowed.
The default is {"before": true, "after": false}
.
An example configuration:
"generator-star-spacing": ["error", {"before": true, "after": false}]
And the option has shorthand as a string keyword:
-
{"before": true, "after": false}
→"before"
-
{"before": false, "after": true}
→"after"
-
{"before": true, "after": true}
→"both"
-
{"before": false, "after": false}
→"neither"
An example of shorthand configuration:
"generator-star-spacing": ["error", "after"]
Examples
before
Examples of correct code for this rule with the "before"
option:
/*eslint generator-star-spacing: ["error", {"before": true, "after": false}]*/
/*eslint-env es6*/
function *generator() {}
var anonymous = function *() {};
var shorthand = { *generator() {} };
after
Examples of correct code for this rule with the "after"
option:
/*eslint generator-star-spacing: ["error", {"before": false, "after": true}]*/
/*eslint-env es6*/
function* generator() {}
var anonymous = function* () {};
var shorthand = { * generator() {} };
both
Examples of correct code for this rule with the "both"
option:
/*eslint generator-star-spacing: ["error", {"before": true, "after": true}]*/
/*eslint-env es6*/
function * generator() {}
var anonymous = function * () {};
var shorthand = { * generator() {} };
neither
Examples of correct code for this rule with the "neither"
option:
/*eslint generator-star-spacing: ["error", {"before": false, "after": false}]*/
/*eslint-env es6*/
function*generator() {}
var anonymous = function*() {};
var shorthand = { *generator() {} };
When Not To Use It
If your project will not be using generators or you are not concerned with spacing consistency, you do not need this rule.
Further Reading
Unexpected space before *. Open
destroy: [ RestAuth, function *(next) {
- Read upRead up
- Exclude checks
Enforce spacing around the * in generator functions (generator-star-spacing)
Generators are a new type of function in ECMAScript 6 that can return multiple values over time.
These special functions are indicated by placing an *
after the function
keyword.
Here is an example of a generator function:
/*eslint-env es6*/
function* generator() {
yield "44";
yield "55";
}
This is also valid:
/*eslint-env es6*/
function *generator() {
yield "44";
yield "55";
}
This is valid as well:
/*eslint-env es6*/
function * generator() {
yield "44";
yield "55";
}
To keep a sense of consistency when using generators this rule enforces a single position for the *
.
Rule Details
This rule aims to enforce spacing around the *
of generator functions.
Options
The rule takes one option, an object, which has two keys before
and after
having boolean values true
or false
.
-
before
enforces spacing between the*
and thefunction
keyword. If it istrue
, a space is required, otherwise spaces are disallowed.
In object literal shorthand methods, spacing before the *
is not checked, as they lack a function
keyword.
-
after
enforces spacing between the*
and the function name (or the opening parenthesis for anonymous generator functions). If it istrue
, a space is required, otherwise spaces are disallowed.
The default is {"before": true, "after": false}
.
An example configuration:
"generator-star-spacing": ["error", {"before": true, "after": false}]
And the option has shorthand as a string keyword:
-
{"before": true, "after": false}
→"before"
-
{"before": false, "after": true}
→"after"
-
{"before": true, "after": true}
→"both"
-
{"before": false, "after": false}
→"neither"
An example of shorthand configuration:
"generator-star-spacing": ["error", "after"]
Examples
before
Examples of correct code for this rule with the "before"
option:
/*eslint generator-star-spacing: ["error", {"before": true, "after": false}]*/
/*eslint-env es6*/
function *generator() {}
var anonymous = function *() {};
var shorthand = { *generator() {} };
after
Examples of correct code for this rule with the "after"
option:
/*eslint generator-star-spacing: ["error", {"before": false, "after": true}]*/
/*eslint-env es6*/
function* generator() {}
var anonymous = function* () {};
var shorthand = { * generator() {} };
both
Examples of correct code for this rule with the "both"
option:
/*eslint generator-star-spacing: ["error", {"before": true, "after": true}]*/
/*eslint-env es6*/
function * generator() {}
var anonymous = function * () {};
var shorthand = { * generator() {} };
neither
Examples of correct code for this rule with the "neither"
option:
/*eslint generator-star-spacing: ["error", {"before": false, "after": false}]*/
/*eslint-env es6*/
function*generator() {}
var anonymous = function*() {};
var shorthand = { *generator() {} };
When Not To Use It
If your project will not be using generators or you are not concerned with spacing consistency, you do not need this rule.
Further Reading
Unexpected space before *. Open
create: [ RestAuth, function *(next) {
- Read upRead up
- Exclude checks
Enforce spacing around the * in generator functions (generator-star-spacing)
Generators are a new type of function in ECMAScript 6 that can return multiple values over time.
These special functions are indicated by placing an *
after the function
keyword.
Here is an example of a generator function:
/*eslint-env es6*/
function* generator() {
yield "44";
yield "55";
}
This is also valid:
/*eslint-env es6*/
function *generator() {
yield "44";
yield "55";
}
This is valid as well:
/*eslint-env es6*/
function * generator() {
yield "44";
yield "55";
}
To keep a sense of consistency when using generators this rule enforces a single position for the *
.
Rule Details
This rule aims to enforce spacing around the *
of generator functions.
Options
The rule takes one option, an object, which has two keys before
and after
having boolean values true
or false
.
-
before
enforces spacing between the*
and thefunction
keyword. If it istrue
, a space is required, otherwise spaces are disallowed.
In object literal shorthand methods, spacing before the *
is not checked, as they lack a function
keyword.
-
after
enforces spacing between the*
and the function name (or the opening parenthesis for anonymous generator functions). If it istrue
, a space is required, otherwise spaces are disallowed.
The default is {"before": true, "after": false}
.
An example configuration:
"generator-star-spacing": ["error", {"before": true, "after": false}]
And the option has shorthand as a string keyword:
-
{"before": true, "after": false}
→"before"
-
{"before": false, "after": true}
→"after"
-
{"before": true, "after": true}
→"both"
-
{"before": false, "after": false}
→"neither"
An example of shorthand configuration:
"generator-star-spacing": ["error", "after"]
Examples
before
Examples of correct code for this rule with the "before"
option:
/*eslint generator-star-spacing: ["error", {"before": true, "after": false}]*/
/*eslint-env es6*/
function *generator() {}
var anonymous = function *() {};
var shorthand = { *generator() {} };
after
Examples of correct code for this rule with the "after"
option:
/*eslint generator-star-spacing: ["error", {"before": false, "after": true}]*/
/*eslint-env es6*/
function* generator() {}
var anonymous = function* () {};
var shorthand = { * generator() {} };
both
Examples of correct code for this rule with the "both"
option:
/*eslint generator-star-spacing: ["error", {"before": true, "after": true}]*/
/*eslint-env es6*/
function * generator() {}
var anonymous = function * () {};
var shorthand = { * generator() {} };
neither
Examples of correct code for this rule with the "neither"
option:
/*eslint generator-star-spacing: ["error", {"before": false, "after": false}]*/
/*eslint-env es6*/
function*generator() {}
var anonymous = function*() {};
var shorthand = { *generator() {} };
When Not To Use It
If your project will not be using generators or you are not concerned with spacing consistency, you do not need this rule.
Further Reading
This generator function does not have 'yield'. Open
edit: function *(next) {
- Read upRead up
- Exclude checks
Disallow generator functions that do not have yield
(require-yield)
Rule Details
This rule generates warnings for generator functions that do not have the yield
keyword.
Examples
Examples of incorrect code for this rule:
/*eslint require-yield: "error"*/
/*eslint-env es6*/
function* foo() {
return 10;
}
Examples of correct code for this rule:
/*eslint require-yield: "error"*/
/*eslint-env es6*/
function* foo() {
yield 5;
return 10;
}
function foo() {
return 10;
}
// This rule does not warn on empty generator functions.
function* foo() { }
When Not To Use It
If you don't want to notify generator functions that have no yield
expression, then it's safe to disable this rule.
Related Rules
- [require-await](require-await.md) Source: http://eslint.org/docs/rules/
Unexpected space before *. Open
show: [ RestAuth, function *(next) {
- Read upRead up
- Exclude checks
Enforce spacing around the * in generator functions (generator-star-spacing)
Generators are a new type of function in ECMAScript 6 that can return multiple values over time.
These special functions are indicated by placing an *
after the function
keyword.
Here is an example of a generator function:
/*eslint-env es6*/
function* generator() {
yield "44";
yield "55";
}
This is also valid:
/*eslint-env es6*/
function *generator() {
yield "44";
yield "55";
}
This is valid as well:
/*eslint-env es6*/
function * generator() {
yield "44";
yield "55";
}
To keep a sense of consistency when using generators this rule enforces a single position for the *
.
Rule Details
This rule aims to enforce spacing around the *
of generator functions.
Options
The rule takes one option, an object, which has two keys before
and after
having boolean values true
or false
.
-
before
enforces spacing between the*
and thefunction
keyword. If it istrue
, a space is required, otherwise spaces are disallowed.
In object literal shorthand methods, spacing before the *
is not checked, as they lack a function
keyword.
-
after
enforces spacing between the*
and the function name (or the opening parenthesis for anonymous generator functions). If it istrue
, a space is required, otherwise spaces are disallowed.
The default is {"before": true, "after": false}
.
An example configuration:
"generator-star-spacing": ["error", {"before": true, "after": false}]
And the option has shorthand as a string keyword:
-
{"before": true, "after": false}
→"before"
-
{"before": false, "after": true}
→"after"
-
{"before": true, "after": true}
→"both"
-
{"before": false, "after": false}
→"neither"
An example of shorthand configuration:
"generator-star-spacing": ["error", "after"]
Examples
before
Examples of correct code for this rule with the "before"
option:
/*eslint generator-star-spacing: ["error", {"before": true, "after": false}]*/
/*eslint-env es6*/
function *generator() {}
var anonymous = function *() {};
var shorthand = { *generator() {} };
after
Examples of correct code for this rule with the "after"
option:
/*eslint generator-star-spacing: ["error", {"before": false, "after": true}]*/
/*eslint-env es6*/
function* generator() {}
var anonymous = function* () {};
var shorthand = { * generator() {} };
both
Examples of correct code for this rule with the "both"
option:
/*eslint generator-star-spacing: ["error", {"before": true, "after": true}]*/
/*eslint-env es6*/
function * generator() {}
var anonymous = function * () {};
var shorthand = { * generator() {} };
neither
Examples of correct code for this rule with the "neither"
option:
/*eslint generator-star-spacing: ["error", {"before": false, "after": false}]*/
/*eslint-env es6*/
function*generator() {}
var anonymous = function*() {};
var shorthand = { *generator() {} };
When Not To Use It
If your project will not be using generators or you are not concerned with spacing consistency, you do not need this rule.
Further Reading
Expected method shorthand. Open
edit: function *(next) {
- Read upRead up
- Exclude checks
Require Object Literal Shorthand Syntax (object-shorthand)
EcmaScript 6 provides a concise form for defining object literal methods and properties. This syntax can make defining complex object literals much cleaner.
Here are a few common examples using the ES5 syntax:
// properties
var foo = {
x: x,
y: y,
z: z,
};
// methods
var foo = {
a: function() {},
b: function() {}
};
Now here are ES6 equivalents:
/*eslint-env es6*/
// properties
var foo = {x, y, z};
// methods
var foo = {
a() {},
b() {}
};
Rule Details
This rule enforces the use of the shorthand syntax. This applies to all methods (including generators) defined in object literals and any properties defined where the key name matches name of the assigned variable.
Each of the following properties would warn:
/*eslint object-shorthand: "error"*/
/*eslint-env es6*/
var foo = {
w: function() {},
x: function *() {},
[y]: function() {},
z: z
};
In that case the expected syntax would have been:
/*eslint object-shorthand: "error"*/
/*eslint-env es6*/
var foo = {
w() {},
*x() {},
[y]() {},
z
};
This rule does not flag arrow functions inside of object literals. The following will not warn:
/*eslint object-shorthand: "error"*/
/*eslint-env es6*/
var foo = {
x: (y) => y
};
Options
The rule takes an option which specifies when it should be applied. It can be set to one of the following values:
-
"always"
(default) expects that the shorthand will be used whenever possible. -
"methods"
ensures the method shorthand is used (also applies to generators). -
"properties"
ensures the property shorthand is used (where the key and variable name match). -
"never"
ensures that no property or method shorthand is used in any object literal. -
"consistent"
ensures that either all shorthand or all longform will be used in an object literal. -
"consistent-as-needed"
ensures that either all shorthand or all longform will be used in an object literal, but ensures all shorthand whenever possible.
You can set the option in configuration like this:
{
"object-shorthand": ["error", "always"]
}
Additionally, the rule takes an optional object configuration:
-
"avoidQuotes": true
indicates that longform syntax is preferred whenever the object key is a string literal (default:false
). Note that this option can only be enabled when the string option is set to"always"
,"methods"
, or"properties"
. -
"ignoreConstructors": true
can be used to prevent the rule from reporting errors for constructor functions. (By default, the rule treats constructors the same way as other functions.) Note that this option can only be enabled when the string option is set to"always"
or"methods"
. -
"avoidExplicitReturnArrows": true
indicates that methods are preferred over explicit-return arrow functions for function properties. (By default, the rule allows either of these.) Note that this option can only be enabled when the string option is set to"always"
or"methods"
.
avoidQuotes
{
"object-shorthand": ["error", "always", { "avoidQuotes": true }]
}
Example of incorrect code for this rule with the "always", { "avoidQuotes": true }
option:
/*eslint object-shorthand: ["error", "always", { "avoidQuotes": true }]*/
/*eslint-env es6*/
var foo = {
"bar-baz"() {}
};
Example of correct code for this rule with the "always", { "avoidQuotes": true }
option:
/*eslint object-shorthand: ["error", "always", { "avoidQuotes": true }]*/
/*eslint-env es6*/
var foo = {
"bar-baz": function() {},
"qux": qux
};
ignoreConstructors
{
"object-shorthand": ["error", "always", { "ignoreConstructors": true }]
}
Example of correct code for this rule with the "always", { "ignoreConstructors": true }
option:
/*eslint object-shorthand: ["error", "always", { "ignoreConstructors": true }]*/
/*eslint-env es6*/
var foo = {
ConstructorFunction: function() {}
};
avoidExplicitReturnArrows
{
"object-shorthand": ["error", "always", { "avoidExplicitReturnArrows": true }]
}
Example of incorrect code for this rule with the "always", { "avoidExplicitReturnArrows": true }
option:
/*eslint object-shorthand: ["error", "always", { "avoidExplicitReturnArrows": true }]*/
/*eslint-env es6*/
var foo = {
foo: (bar, baz) => {
return bar + baz;
},
qux: (foobar) => {
return foobar * 2;
}
};
Example of correct code for this rule with the "always", { "avoidExplicitReturnArrows": true }
option:
/*eslint object-shorthand: ["error", "always", { "avoidExplicitReturnArrows": true }]*/
/*eslint-env es6*/
var foo = {
foo(bar, baz) {
return bar + baz;
},
qux: foobar => foobar * 2
};
Example of incorrect code for this rule with the "consistent"
option:
/*eslint object-shorthand: [2, "consistent"]*/
/*eslint-env es6*/
var foo = {
a,
b: "foo",
};
Examples of correct code for this rule with the "consistent"
option:
/*eslint object-shorthand: [2, "consistent"]*/
/*eslint-env es6*/
var foo = {
a: a,
b: "foo"
};
var bar = {
a,
b,
};
Example of incorrect code with the "consistent-as-needed"
option, which is very similar to "consistent"
:
/*eslint object-shorthand: [2, "consistent-as-needed"]*/
/*eslint-env es6*/
var foo = {
a: a,
b: b,
};
When Not To Use It
Anyone not yet in an ES6 environment would not want to apply this rule. Others may find the terseness of the shorthand syntax harder to read and may not want to encourage it with this rule.
Further Reading
Object initializer - MDN Source: http://eslint.org/docs/rules/
Unexpected space before *. Open
edit: function *(next) {
- Read upRead up
- Exclude checks
Enforce spacing around the * in generator functions (generator-star-spacing)
Generators are a new type of function in ECMAScript 6 that can return multiple values over time.
These special functions are indicated by placing an *
after the function
keyword.
Here is an example of a generator function:
/*eslint-env es6*/
function* generator() {
yield "44";
yield "55";
}
This is also valid:
/*eslint-env es6*/
function *generator() {
yield "44";
yield "55";
}
This is valid as well:
/*eslint-env es6*/
function * generator() {
yield "44";
yield "55";
}
To keep a sense of consistency when using generators this rule enforces a single position for the *
.
Rule Details
This rule aims to enforce spacing around the *
of generator functions.
Options
The rule takes one option, an object, which has two keys before
and after
having boolean values true
or false
.
-
before
enforces spacing between the*
and thefunction
keyword. If it istrue
, a space is required, otherwise spaces are disallowed.
In object literal shorthand methods, spacing before the *
is not checked, as they lack a function
keyword.
-
after
enforces spacing between the*
and the function name (or the opening parenthesis for anonymous generator functions). If it istrue
, a space is required, otherwise spaces are disallowed.
The default is {"before": true, "after": false}
.
An example configuration:
"generator-star-spacing": ["error", {"before": true, "after": false}]
And the option has shorthand as a string keyword:
-
{"before": true, "after": false}
→"before"
-
{"before": false, "after": true}
→"after"
-
{"before": true, "after": true}
→"both"
-
{"before": false, "after": false}
→"neither"
An example of shorthand configuration:
"generator-star-spacing": ["error", "after"]
Examples
before
Examples of correct code for this rule with the "before"
option:
/*eslint generator-star-spacing: ["error", {"before": true, "after": false}]*/
/*eslint-env es6*/
function *generator() {}
var anonymous = function *() {};
var shorthand = { *generator() {} };
after
Examples of correct code for this rule with the "after"
option:
/*eslint generator-star-spacing: ["error", {"before": false, "after": true}]*/
/*eslint-env es6*/
function* generator() {}
var anonymous = function* () {};
var shorthand = { * generator() {} };
both
Examples of correct code for this rule with the "both"
option:
/*eslint generator-star-spacing: ["error", {"before": true, "after": true}]*/
/*eslint-env es6*/
function * generator() {}
var anonymous = function * () {};
var shorthand = { * generator() {} };
neither
Examples of correct code for this rule with the "neither"
option:
/*eslint generator-star-spacing: ["error", {"before": false, "after": false}]*/
/*eslint-env es6*/
function*generator() {}
var anonymous = function*() {};
var shorthand = { *generator() {} };
When Not To Use It
If your project will not be using generators or you are not concerned with spacing consistency, you do not need this rule.
Further Reading
Missing space after *. Open
update: [ RestAuth, function *(next) {
- Read upRead up
- Exclude checks
Enforce spacing around the * in generator functions (generator-star-spacing)
Generators are a new type of function in ECMAScript 6 that can return multiple values over time.
These special functions are indicated by placing an *
after the function
keyword.
Here is an example of a generator function:
/*eslint-env es6*/
function* generator() {
yield "44";
yield "55";
}
This is also valid:
/*eslint-env es6*/
function *generator() {
yield "44";
yield "55";
}
This is valid as well:
/*eslint-env es6*/
function * generator() {
yield "44";
yield "55";
}
To keep a sense of consistency when using generators this rule enforces a single position for the *
.
Rule Details
This rule aims to enforce spacing around the *
of generator functions.
Options
The rule takes one option, an object, which has two keys before
and after
having boolean values true
or false
.
-
before
enforces spacing between the*
and thefunction
keyword. If it istrue
, a space is required, otherwise spaces are disallowed.
In object literal shorthand methods, spacing before the *
is not checked, as they lack a function
keyword.
-
after
enforces spacing between the*
and the function name (or the opening parenthesis for anonymous generator functions). If it istrue
, a space is required, otherwise spaces are disallowed.
The default is {"before": true, "after": false}
.
An example configuration:
"generator-star-spacing": ["error", {"before": true, "after": false}]
And the option has shorthand as a string keyword:
-
{"before": true, "after": false}
→"before"
-
{"before": false, "after": true}
→"after"
-
{"before": true, "after": true}
→"both"
-
{"before": false, "after": false}
→"neither"
An example of shorthand configuration:
"generator-star-spacing": ["error", "after"]
Examples
before
Examples of correct code for this rule with the "before"
option:
/*eslint generator-star-spacing: ["error", {"before": true, "after": false}]*/
/*eslint-env es6*/
function *generator() {}
var anonymous = function *() {};
var shorthand = { *generator() {} };
after
Examples of correct code for this rule with the "after"
option:
/*eslint generator-star-spacing: ["error", {"before": false, "after": true}]*/
/*eslint-env es6*/
function* generator() {}
var anonymous = function* () {};
var shorthand = { * generator() {} };
both
Examples of correct code for this rule with the "both"
option:
/*eslint generator-star-spacing: ["error", {"before": true, "after": true}]*/
/*eslint-env es6*/
function * generator() {}
var anonymous = function * () {};
var shorthand = { * generator() {} };
neither
Examples of correct code for this rule with the "neither"
option:
/*eslint generator-star-spacing: ["error", {"before": false, "after": false}]*/
/*eslint-env es6*/
function*generator() {}
var anonymous = function*() {};
var shorthand = { *generator() {} };
When Not To Use It
If your project will not be using generators or you are not concerned with spacing consistency, you do not need this rule.
Further Reading
Unexpected empty generator function. Open
update: [ RestAuth, function *(next) {
- Read upRead up
- Exclude checks
Disallow empty functions (no-empty-function)
Empty functions can reduce readability because readers need to guess whether it's intentional or not. So writing a clear comment for empty functions is a good practice.
function foo() {
// do nothing.
}
Especially, the empty block of arrow functions might be confusing developers. It's very similar to an empty object literal.
list.map(() => {}); // This is a block, would return undefined.
list.map(() => ({})); // This is an empty object.
Rule Details
This rule is aimed at eliminating empty functions. A function will not be considered a problem if it contains a comment.
Examples of incorrect code for this rule:
/*eslint no-empty-function: "error"*/
/*eslint-env es6*/
function foo() {}
var foo = function() {};
var foo = () => {};
function* foo() {}
var foo = function*() {};
var obj = {
foo: function() {},
foo: function*() {},
foo() {},
*foo() {},
get foo() {},
set foo(value) {}
};
class A {
constructor() {}
foo() {}
*foo() {}
get foo() {}
set foo(value) {}
static foo() {}
static *foo() {}
static get foo() {}
static set foo(value) {}
}
Examples of correct code for this rule:
/*eslint no-empty-function: "error"*/
/*eslint-env es6*/
function foo() {
// do nothing.
}
var foo = function() {
// any clear comments.
};
var foo = () => {
bar();
};
function* foo() {
// do nothing.
}
var foo = function*() {
// do nothing.
};
var obj = {
foo: function() {
// do nothing.
},
foo: function*() {
// do nothing.
},
foo() {
// do nothing.
},
*foo() {
// do nothing.
},
get foo() {
// do nothing.
},
set foo(value) {
// do nothing.
}
};
class A {
constructor() {
// do nothing.
}
foo() {
// do nothing.
}
*foo() {
// do nothing.
}
get foo() {
// do nothing.
}
set foo(value) {
// do nothing.
}
static foo() {
// do nothing.
}
static *foo() {
// do nothing.
}
static get foo() {
// do nothing.
}
static set foo(value) {
// do nothing.
}
}
Options
This rule has an option to allow specific kinds of functions to be empty.
-
allow
(string[]
) - A list of kind to allow empty functions. List items are some of the following strings. An empty array ([]
) by default.-
"functions"
- Normal functions. -
"arrowFunctions"
- Arrow functions. -
"generatorFunctions"
- Generator functions. -
"methods"
- Class methods and method shorthands of object literals. -
"generatorMethods"
- Class methods and method shorthands of object literals with generator. -
"getters"
- Getters. -
"setters"
- Setters. -
"constructors"
- Class constructors.
-
allow: functions
Examples of correct code for the { "allow": ["functions"] }
option:
/*eslint no-empty-function: ["error", { "allow": ["functions"] }]*/
function foo() {}
var foo = function() {};
var obj = {
foo: function() {}
};
allow: arrowFunctions
Examples of correct code for the { "allow": ["arrowFunctions"] }
option:
/*eslint no-empty-function: ["error", { "allow": ["arrowFunctions"] }]*/
/*eslint-env es6*/
var foo = () => {};
allow: generatorFunctions
Examples of correct code for the { "allow": ["generatorFunctions"] }
option:
/*eslint no-empty-function: ["error", { "allow": ["generatorFunctions"] }]*/
/*eslint-env es6*/
function* foo() {}
var foo = function*() {};
var obj = {
foo: function*() {}
};
allow: methods
Examples of correct code for the { "allow": ["methods"] }
option:
/*eslint no-empty-function: ["error", { "allow": ["methods"] }]*/
/*eslint-env es6*/
var obj = {
foo() {}
};
class A {
foo() {}
static foo() {}
}
allow: generatorMethods
Examples of correct code for the { "allow": ["generatorMethods"] }
option:
/*eslint no-empty-function: ["error", { "allow": ["generatorMethods"] }]*/
/*eslint-env es6*/
var obj = {
*foo() {}
};
class A {
*foo() {}
static *foo() {}
}
allow: getters
Examples of correct code for the { "allow": ["getters"] }
option:
/*eslint no-empty-function: ["error", { "allow": ["getters"] }]*/
/*eslint-env es6*/
var obj = {
get foo() {}
};
class A {
get foo() {}
static get foo() {}
}
allow: setters
Examples of correct code for the { "allow": ["setters"] }
option:
/*eslint no-empty-function: ["error", { "allow": ["setters"] }]*/
/*eslint-env es6*/
var obj = {
set foo(value) {}
};
class A {
set foo(value) {}
static set foo(value) {}
}
allow: constructors
Examples of correct code for the { "allow": ["constructors"] }
option:
/*eslint no-empty-function: ["error", { "allow": ["constructors"] }]*/
/*eslint-env es6*/
class A {
constructor() {}
}
When Not To Use It
If you don't want to be notified about empty functions, then it's safe to disable this rule.
Related Rules
- [no-empty](./no-empty.md) Source: http://eslint.org/docs/rules/
Unexpected empty generator function. Open
create: [ RestAuth, function *(next) {
- Read upRead up
- Exclude checks
Disallow empty functions (no-empty-function)
Empty functions can reduce readability because readers need to guess whether it's intentional or not. So writing a clear comment for empty functions is a good practice.
function foo() {
// do nothing.
}
Especially, the empty block of arrow functions might be confusing developers. It's very similar to an empty object literal.
list.map(() => {}); // This is a block, would return undefined.
list.map(() => ({})); // This is an empty object.
Rule Details
This rule is aimed at eliminating empty functions. A function will not be considered a problem if it contains a comment.
Examples of incorrect code for this rule:
/*eslint no-empty-function: "error"*/
/*eslint-env es6*/
function foo() {}
var foo = function() {};
var foo = () => {};
function* foo() {}
var foo = function*() {};
var obj = {
foo: function() {},
foo: function*() {},
foo() {},
*foo() {},
get foo() {},
set foo(value) {}
};
class A {
constructor() {}
foo() {}
*foo() {}
get foo() {}
set foo(value) {}
static foo() {}
static *foo() {}
static get foo() {}
static set foo(value) {}
}
Examples of correct code for this rule:
/*eslint no-empty-function: "error"*/
/*eslint-env es6*/
function foo() {
// do nothing.
}
var foo = function() {
// any clear comments.
};
var foo = () => {
bar();
};
function* foo() {
// do nothing.
}
var foo = function*() {
// do nothing.
};
var obj = {
foo: function() {
// do nothing.
},
foo: function*() {
// do nothing.
},
foo() {
// do nothing.
},
*foo() {
// do nothing.
},
get foo() {
// do nothing.
},
set foo(value) {
// do nothing.
}
};
class A {
constructor() {
// do nothing.
}
foo() {
// do nothing.
}
*foo() {
// do nothing.
}
get foo() {
// do nothing.
}
set foo(value) {
// do nothing.
}
static foo() {
// do nothing.
}
static *foo() {
// do nothing.
}
static get foo() {
// do nothing.
}
static set foo(value) {
// do nothing.
}
}
Options
This rule has an option to allow specific kinds of functions to be empty.
-
allow
(string[]
) - A list of kind to allow empty functions. List items are some of the following strings. An empty array ([]
) by default.-
"functions"
- Normal functions. -
"arrowFunctions"
- Arrow functions. -
"generatorFunctions"
- Generator functions. -
"methods"
- Class methods and method shorthands of object literals. -
"generatorMethods"
- Class methods and method shorthands of object literals with generator. -
"getters"
- Getters. -
"setters"
- Setters. -
"constructors"
- Class constructors.
-
allow: functions
Examples of correct code for the { "allow": ["functions"] }
option:
/*eslint no-empty-function: ["error", { "allow": ["functions"] }]*/
function foo() {}
var foo = function() {};
var obj = {
foo: function() {}
};
allow: arrowFunctions
Examples of correct code for the { "allow": ["arrowFunctions"] }
option:
/*eslint no-empty-function: ["error", { "allow": ["arrowFunctions"] }]*/
/*eslint-env es6*/
var foo = () => {};
allow: generatorFunctions
Examples of correct code for the { "allow": ["generatorFunctions"] }
option:
/*eslint no-empty-function: ["error", { "allow": ["generatorFunctions"] }]*/
/*eslint-env es6*/
function* foo() {}
var foo = function*() {};
var obj = {
foo: function*() {}
};
allow: methods
Examples of correct code for the { "allow": ["methods"] }
option:
/*eslint no-empty-function: ["error", { "allow": ["methods"] }]*/
/*eslint-env es6*/
var obj = {
foo() {}
};
class A {
foo() {}
static foo() {}
}
allow: generatorMethods
Examples of correct code for the { "allow": ["generatorMethods"] }
option:
/*eslint no-empty-function: ["error", { "allow": ["generatorMethods"] }]*/
/*eslint-env es6*/
var obj = {
*foo() {}
};
class A {
*foo() {}
static *foo() {}
}
allow: getters
Examples of correct code for the { "allow": ["getters"] }
option:
/*eslint no-empty-function: ["error", { "allow": ["getters"] }]*/
/*eslint-env es6*/
var obj = {
get foo() {}
};
class A {
get foo() {}
static get foo() {}
}
allow: setters
Examples of correct code for the { "allow": ["setters"] }
option:
/*eslint no-empty-function: ["error", { "allow": ["setters"] }]*/
/*eslint-env es6*/
var obj = {
set foo(value) {}
};
class A {
set foo(value) {}
static set foo(value) {}
}
allow: constructors
Examples of correct code for the { "allow": ["constructors"] }
option:
/*eslint no-empty-function: ["error", { "allow": ["constructors"] }]*/
/*eslint-env es6*/
class A {
constructor() {}
}
When Not To Use It
If you don't want to be notified about empty functions, then it's safe to disable this rule.
Related Rules
- [no-empty](./no-empty.md) Source: http://eslint.org/docs/rules/
Unexpected empty generator function. Open
show: [ RestAuth, function *(next) {
- Read upRead up
- Exclude checks
Disallow empty functions (no-empty-function)
Empty functions can reduce readability because readers need to guess whether it's intentional or not. So writing a clear comment for empty functions is a good practice.
function foo() {
// do nothing.
}
Especially, the empty block of arrow functions might be confusing developers. It's very similar to an empty object literal.
list.map(() => {}); // This is a block, would return undefined.
list.map(() => ({})); // This is an empty object.
Rule Details
This rule is aimed at eliminating empty functions. A function will not be considered a problem if it contains a comment.
Examples of incorrect code for this rule:
/*eslint no-empty-function: "error"*/
/*eslint-env es6*/
function foo() {}
var foo = function() {};
var foo = () => {};
function* foo() {}
var foo = function*() {};
var obj = {
foo: function() {},
foo: function*() {},
foo() {},
*foo() {},
get foo() {},
set foo(value) {}
};
class A {
constructor() {}
foo() {}
*foo() {}
get foo() {}
set foo(value) {}
static foo() {}
static *foo() {}
static get foo() {}
static set foo(value) {}
}
Examples of correct code for this rule:
/*eslint no-empty-function: "error"*/
/*eslint-env es6*/
function foo() {
// do nothing.
}
var foo = function() {
// any clear comments.
};
var foo = () => {
bar();
};
function* foo() {
// do nothing.
}
var foo = function*() {
// do nothing.
};
var obj = {
foo: function() {
// do nothing.
},
foo: function*() {
// do nothing.
},
foo() {
// do nothing.
},
*foo() {
// do nothing.
},
get foo() {
// do nothing.
},
set foo(value) {
// do nothing.
}
};
class A {
constructor() {
// do nothing.
}
foo() {
// do nothing.
}
*foo() {
// do nothing.
}
get foo() {
// do nothing.
}
set foo(value) {
// do nothing.
}
static foo() {
// do nothing.
}
static *foo() {
// do nothing.
}
static get foo() {
// do nothing.
}
static set foo(value) {
// do nothing.
}
}
Options
This rule has an option to allow specific kinds of functions to be empty.
-
allow
(string[]
) - A list of kind to allow empty functions. List items are some of the following strings. An empty array ([]
) by default.-
"functions"
- Normal functions. -
"arrowFunctions"
- Arrow functions. -
"generatorFunctions"
- Generator functions. -
"methods"
- Class methods and method shorthands of object literals. -
"generatorMethods"
- Class methods and method shorthands of object literals with generator. -
"getters"
- Getters. -
"setters"
- Setters. -
"constructors"
- Class constructors.
-
allow: functions
Examples of correct code for the { "allow": ["functions"] }
option:
/*eslint no-empty-function: ["error", { "allow": ["functions"] }]*/
function foo() {}
var foo = function() {};
var obj = {
foo: function() {}
};
allow: arrowFunctions
Examples of correct code for the { "allow": ["arrowFunctions"] }
option:
/*eslint no-empty-function: ["error", { "allow": ["arrowFunctions"] }]*/
/*eslint-env es6*/
var foo = () => {};
allow: generatorFunctions
Examples of correct code for the { "allow": ["generatorFunctions"] }
option:
/*eslint no-empty-function: ["error", { "allow": ["generatorFunctions"] }]*/
/*eslint-env es6*/
function* foo() {}
var foo = function*() {};
var obj = {
foo: function*() {}
};
allow: methods
Examples of correct code for the { "allow": ["methods"] }
option:
/*eslint no-empty-function: ["error", { "allow": ["methods"] }]*/
/*eslint-env es6*/
var obj = {
foo() {}
};
class A {
foo() {}
static foo() {}
}
allow: generatorMethods
Examples of correct code for the { "allow": ["generatorMethods"] }
option:
/*eslint no-empty-function: ["error", { "allow": ["generatorMethods"] }]*/
/*eslint-env es6*/
var obj = {
*foo() {}
};
class A {
*foo() {}
static *foo() {}
}
allow: getters
Examples of correct code for the { "allow": ["getters"] }
option:
/*eslint no-empty-function: ["error", { "allow": ["getters"] }]*/
/*eslint-env es6*/
var obj = {
get foo() {}
};
class A {
get foo() {}
static get foo() {}
}
allow: setters
Examples of correct code for the { "allow": ["setters"] }
option:
/*eslint no-empty-function: ["error", { "allow": ["setters"] }]*/
/*eslint-env es6*/
var obj = {
set foo(value) {}
};
class A {
set foo(value) {}
static set foo(value) {}
}
allow: constructors
Examples of correct code for the { "allow": ["constructors"] }
option:
/*eslint no-empty-function: ["error", { "allow": ["constructors"] }]*/
/*eslint-env es6*/
class A {
constructor() {}
}
When Not To Use It
If you don't want to be notified about empty functions, then it's safe to disable this rule.
Related Rules
- [no-empty](./no-empty.md) Source: http://eslint.org/docs/rules/
Unexpected empty generator function. Open
destroy: [ RestAuth, function *(next) {
- Read upRead up
- Exclude checks
Disallow empty functions (no-empty-function)
Empty functions can reduce readability because readers need to guess whether it's intentional or not. So writing a clear comment for empty functions is a good practice.
function foo() {
// do nothing.
}
Especially, the empty block of arrow functions might be confusing developers. It's very similar to an empty object literal.
list.map(() => {}); // This is a block, would return undefined.
list.map(() => ({})); // This is an empty object.
Rule Details
This rule is aimed at eliminating empty functions. A function will not be considered a problem if it contains a comment.
Examples of incorrect code for this rule:
/*eslint no-empty-function: "error"*/
/*eslint-env es6*/
function foo() {}
var foo = function() {};
var foo = () => {};
function* foo() {}
var foo = function*() {};
var obj = {
foo: function() {},
foo: function*() {},
foo() {},
*foo() {},
get foo() {},
set foo(value) {}
};
class A {
constructor() {}
foo() {}
*foo() {}
get foo() {}
set foo(value) {}
static foo() {}
static *foo() {}
static get foo() {}
static set foo(value) {}
}
Examples of correct code for this rule:
/*eslint no-empty-function: "error"*/
/*eslint-env es6*/
function foo() {
// do nothing.
}
var foo = function() {
// any clear comments.
};
var foo = () => {
bar();
};
function* foo() {
// do nothing.
}
var foo = function*() {
// do nothing.
};
var obj = {
foo: function() {
// do nothing.
},
foo: function*() {
// do nothing.
},
foo() {
// do nothing.
},
*foo() {
// do nothing.
},
get foo() {
// do nothing.
},
set foo(value) {
// do nothing.
}
};
class A {
constructor() {
// do nothing.
}
foo() {
// do nothing.
}
*foo() {
// do nothing.
}
get foo() {
// do nothing.
}
set foo(value) {
// do nothing.
}
static foo() {
// do nothing.
}
static *foo() {
// do nothing.
}
static get foo() {
// do nothing.
}
static set foo(value) {
// do nothing.
}
}
Options
This rule has an option to allow specific kinds of functions to be empty.
-
allow
(string[]
) - A list of kind to allow empty functions. List items are some of the following strings. An empty array ([]
) by default.-
"functions"
- Normal functions. -
"arrowFunctions"
- Arrow functions. -
"generatorFunctions"
- Generator functions. -
"methods"
- Class methods and method shorthands of object literals. -
"generatorMethods"
- Class methods and method shorthands of object literals with generator. -
"getters"
- Getters. -
"setters"
- Setters. -
"constructors"
- Class constructors.
-
allow: functions
Examples of correct code for the { "allow": ["functions"] }
option:
/*eslint no-empty-function: ["error", { "allow": ["functions"] }]*/
function foo() {}
var foo = function() {};
var obj = {
foo: function() {}
};
allow: arrowFunctions
Examples of correct code for the { "allow": ["arrowFunctions"] }
option:
/*eslint no-empty-function: ["error", { "allow": ["arrowFunctions"] }]*/
/*eslint-env es6*/
var foo = () => {};
allow: generatorFunctions
Examples of correct code for the { "allow": ["generatorFunctions"] }
option:
/*eslint no-empty-function: ["error", { "allow": ["generatorFunctions"] }]*/
/*eslint-env es6*/
function* foo() {}
var foo = function*() {};
var obj = {
foo: function*() {}
};
allow: methods
Examples of correct code for the { "allow": ["methods"] }
option:
/*eslint no-empty-function: ["error", { "allow": ["methods"] }]*/
/*eslint-env es6*/
var obj = {
foo() {}
};
class A {
foo() {}
static foo() {}
}
allow: generatorMethods
Examples of correct code for the { "allow": ["generatorMethods"] }
option:
/*eslint no-empty-function: ["error", { "allow": ["generatorMethods"] }]*/
/*eslint-env es6*/
var obj = {
*foo() {}
};
class A {
*foo() {}
static *foo() {}
}
allow: getters
Examples of correct code for the { "allow": ["getters"] }
option:
/*eslint no-empty-function: ["error", { "allow": ["getters"] }]*/
/*eslint-env es6*/
var obj = {
get foo() {}
};
class A {
get foo() {}
static get foo() {}
}
allow: setters
Examples of correct code for the { "allow": ["setters"] }
option:
/*eslint no-empty-function: ["error", { "allow": ["setters"] }]*/
/*eslint-env es6*/
var obj = {
set foo(value) {}
};
class A {
set foo(value) {}
static set foo(value) {}
}
allow: constructors
Examples of correct code for the { "allow": ["constructors"] }
option:
/*eslint no-empty-function: ["error", { "allow": ["constructors"] }]*/
/*eslint-env es6*/
class A {
constructor() {}
}
When Not To Use It
If you don't want to be notified about empty functions, then it's safe to disable this rule.
Related Rules
- [no-empty](./no-empty.md) Source: http://eslint.org/docs/rules/