mirror of
https://git.proxmox.com/git/pve-eslint
synced 2025-10-05 20:14:12 +00:00
eb39fafa4f
includes a (minimal) working wrapper Signed-off-by: Dominik Csapak <d.csapak@proxmox.com>
85 lines
2.1 KiB
Markdown
85 lines
2.1 KiB
Markdown
# Require Consistent This (consistent-this)
|
|
|
|
It is often necessary to capture the current execution context in order to make it available subsequently. A prominent example of this are jQuery callbacks:
|
|
|
|
```js
|
|
var that = this;
|
|
jQuery('li').click(function (event) {
|
|
// here, "this" is the HTMLElement where the click event occurred
|
|
that.setFoo(42);
|
|
});
|
|
```
|
|
|
|
There are many commonly used aliases for `this` such as `that`, `self` or `me`. It is desirable to ensure that whichever alias the team agrees upon is used consistently throughout the application.
|
|
|
|
## Rule Details
|
|
|
|
This rule enforces two things about variables with the designated alias names for `this`:
|
|
|
|
* If a variable with a designated name is declared, it *must* be either initialized (in the declaration) or assigned (in the same scope as the declaration) the value `this`.
|
|
* If a variable is initialized or assigned the value `this`, the name of the variable *must* be a designated alias.
|
|
|
|
## Options
|
|
|
|
This rule has one or more string options:
|
|
|
|
* designated alias names for `this` (default `"that"`)
|
|
|
|
Examples of **incorrect** code for this rule with the default `"that"` option:
|
|
|
|
```js
|
|
/*eslint consistent-this: ["error", "that"]*/
|
|
|
|
var that = 42;
|
|
|
|
var self = this;
|
|
|
|
that = 42;
|
|
|
|
self = this;
|
|
```
|
|
|
|
Examples of **correct** code for this rule with the default `"that"` option:
|
|
|
|
```js
|
|
/*eslint consistent-this: ["error", "that"]*/
|
|
|
|
var that = this;
|
|
|
|
var self = 42;
|
|
|
|
var self;
|
|
|
|
that = this;
|
|
|
|
foo.bar = this;
|
|
```
|
|
|
|
Examples of **incorrect** code for this rule with the default `"that"` option, if the variable is not initialized:
|
|
|
|
```js
|
|
/*eslint consistent-this: ["error", "that"]*/
|
|
|
|
var that;
|
|
function f() {
|
|
that = this;
|
|
}
|
|
```
|
|
|
|
Examples of **correct** code for this rule with the default `"that"` option, if the variable is not initialized:
|
|
|
|
```js
|
|
/*eslint consistent-this: ["error", "that"]*/
|
|
|
|
var that;
|
|
that = this;
|
|
|
|
var foo, that;
|
|
foo = 42;
|
|
that = this;
|
|
```
|
|
|
|
## When Not To Use It
|
|
|
|
If you need to capture nested context, `consistent-this` is going to be problematic. Code of that nature is usually difficult to read and maintain and you should consider refactoring it.
|