@putout/plugin-declare-undefined-variables [![NPM version][NPMIMGURL]][NPMURL]

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🐊Putout plugin adds ability to declare variable that was not defined before, including:

- is types: isFn, isString, isNumber, isObject, isBool, isUndefined, isSymbol and isNull;
- maybe: maybeArray, maybeFn, maybeEmptyArray;
- wrap: not,id, returns;
- fresh-import: freshImport, freshImportDefault;
- fixtures: readFixture(name);
- properties of Object;
- wraptile;
- fullstore;
- currify;
- pipe-io;
- pullout;
- simport;
- chalk;
- table;

Renamed to @putout/plugin-declare.

Install

``
npm i putout @putout/plugin-declare-undefined-variables -D
`

Add .putout.json with:

`json
{
"plugins": {
"declare-undefined-variables": "on"
}
}
`

Rules

Use options:

- ✅ dismiss for variables you don't want to declare;
- ✅ declarations to declare variables;

`json
{
"rules": {
"declare-undefined-variables": ["on", {
"declarations": {
"hello": "import {hello} from 'world'"
},
"dismiss": [
"assert",
"entries",
"parse",
"stringify",
"defineProperty",
"isArray",
"noop",
"join",
"keys",
"values",
"stopAll",
"once",
"putout",
"simport"
]
}]
}
}
`

assign

❌ Example of incorrect code

`js
const hello = 'world';
const object = {};

assign(object, {
hello,
});
`

✅ Example of correct code

`js
const hello = 'world';
const object = {};
const {assign} = Object;

assign(object, {
hello,
});
`

keys

❌ Example of incorrect code

`js
const hello = 'world';
const object = {};

const allKeys = keys(object);
`

✅ Example of correct code

`js
const hello = 'world';
const object = {};
const {keys} = Object;

const allKeys = keys(object);
`

values

❌ Example of incorrect code

`js
const object = {};
const allValues = values(object);
`

✅ Example of correct code

`js
const {values} = Object;

const object = {};
const allValues = values(object);
`

isArray

❌ Example of incorrect code

`js
isArray(array);
`

✅ Example of correct code

`js
const {isArray} = Array;
isArray(array);
`

noop

❌ Example of incorrect code

`js
noop();
`

✅ Example of correct code

`js
const noop = () => {};
noop();
`

Types

❌ Example of incorrect code

`js
if (isFn(fn))
fn();
`

✅ Example of correct code

`js
const isFn = (a) => typeof a === 'function';

if (isFn(fn))
fn();
`

Maybe

❌ Example of incorrect code

`js
const a = [
...maybeArray(b),
];
`

✅ Example of correct code

`js
const {isArray} = Array;
const maybeArray = (a) => isArray(a) ? a : [a];

const a = [
...maybeArray(b),
];
``

License

MIT