eslint/docs/src/rules/getter-return.md

   1 ---
   2 title: getter-return
   3 layout: doc
   4 rule_type: problem
   5 further_reading:
   6 - https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions/get
   7 - https://leanpub.com/understandinges6/read/#leanpub-auto-accessor-properties
   8 ---
   9
  10
  11
  12 The get syntax binds an object property to a function that will be called when that property is looked up. It was first introduced in ECMAScript 5:
  13
  14 ```js
  15 var p = {
  16     get name(){
  17         return "nicholas";
  18     }
  19 };
  20
  21 Object.defineProperty(p, "age", {
  22     get: function (){
  23         return 17;
  24     }
  25 });
  26 ```
  27
  28 Note that every `getter` is expected to return a value.
  29
  30 ## Rule Details
  31
  32 This rule enforces that a return statement is present in property getters.
  33
  34 Examples of **incorrect** code for this rule:
  35
  36 ::: incorrect
  37
  38 ```js
  39 /*eslint getter-return: "error"*/
  40
  41 p = {
  42     get name(){
  43         // no returns.
  44     }
  45 };
  46
  47 Object.defineProperty(p, "age", {
  48     get: function (){
  49         // no returns.
  50     }
  51 });
  52
  53 class P{
  54     get name(){
  55         // no returns.
  56     }
  57 }
  58 ```
  59
  60 :::
  61
  62 Examples of **correct** code for this rule:
  63
  64 ::: correct
  65
  66 ```js
  67 /*eslint getter-return: "error"*/
  68
  69 p = {
  70     get name(){
  71         return "nicholas";
  72     }
  73 };
  74
  75 Object.defineProperty(p, "age", {
  76     get: function (){
  77         return 18;
  78     }
  79 });
  80
  81 class P{
  82     get name(){
  83         return "nicholas";
  84     }
  85 }
  86 ```
  87
  88 :::
  89
  90 ## Options
  91
  92 This rule has an object option:
  93
  94 * `"allowImplicit": false` (default) disallows implicitly returning `undefined` with a `return` statement.
  95
  96 Examples of **correct** code for the `{ "allowImplicit": true }` option:
  97
  98 ::: correct
  99
 100 ```js
 101 /*eslint getter-return: ["error", { allowImplicit: true }]*/
 102 p = {
 103     get name(){
 104         return; // return undefined implicitly.
 105     }
 106 };
 107 ```
 108
 109 :::
 110
 111 ## When Not To Use It
 112
 113 If your project will not be using ES5 property getters you do not need this rule.