orionsoft-react-scripts/node_modules/jsx-ast-utils/README.md

Orionsoft Configuration and scripts for Create React App.

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# jsx-ast-utils

AST utility module for statically analyzing JSX.

## Installation
```sh
$ npm i jsx-ast-utils --save
```

## Usage
This is a utility module to evaluate AST objects for JSX syntax. This can be super useful when writing linting rules for JSX code. It was originally in the code for [eslint-plugin-jsx-a11y](https://github.com/evcohen/eslint-plugin-jsx-a11y), however I thought it could be useful to be extracted and maintained separately so **you** could write new interesting rules to statically analyze JSX.

### ESLint example
```js
import { hasProp } from 'jsx-ast-utils';
// OR: var hasProp = require('jsx-ast-utils').hasProp;
// OR: const hasProp = require('jsx-ast-utils/hasProp');
// OR: import hasProp from 'jsx-ast-utils/hasProp';

module.exports = context => ({
  JSXOpeningElement: node => {
    const onChange = hasProp(node.attributes, 'onChange');

    if (onChange) {
      context.report({
        node,
        message: `No onChange!`
      });
    }
  }
});
```

## API
### AST Resources
1. [JSX spec](https://github.com/facebook/jsx/blob/master/AST.md)
2. [JS spec](https://github.com/estree/estree/blob/master/spec.md)

### hasProp
```js
hasProp(props, prop, options);
```
Returns boolean indicating whether an prop exists as an attribute on a JSX element node.

#### Props
Object - The attributes on the visited node. (Usually `node.attributes`).
#### Prop
String - A string representation of the prop you want to check for existence.
#### Options
Object - An object representing options for existence checking
  1. `ignoreCase` - automatically set to `true`.
  2. `spreadStrict` - automatically set to `true`. This means if spread operator exists in
     props, it will assume the prop you are looking for is not in the spread.
     Example: `<div {...props} />` looking for specific prop here will return false if `spreadStrict` is `true`.

<hr />
### hasAnyProp
```js
hasAnyProp(props, prop, options);
```
Returns a boolean indicating if **any** of props in `prop` argument exist on the node.

#### Props
Object - The attributes on the visited node. (Usually `node.attributes`).
#### Prop
Array<String> - An array of strings representing the props you want to check for existence.
#### Options
Object - An object representing options for existence checking
  1. `ignoreCase` - automatically set to `true`.
  2. `spreadStrict` - automatically set to `true`. This means if spread operator exists in
     props, it will assume the prop you are looking for is not in the spread.
     Example: `<div {...props} />` looking for specific prop here will return false if `spreadStrict` is `true`.

<hr />
### hasEveryProp
```js
hasEveryProp(props, prop, options);
```
Returns a boolean indicating if **all** of props in `prop` argument exist on the node.

#### Props
Object - The attributes on the visited node. (Usually `node.attributes`).
#### Prop
Array<String> - An array of strings representing the props you want to check for existence.
#### Options
Object - An object representing options for existence checking
 1. `ignoreCase` - automatically set to `true`.
 2. `spreadStrict` - automatically set to `true`. This means if spread operator exists in
    props, it will assume the prop you are looking for is not in the spread.
    Example: `<div {...props} />` looking for specific prop here will return false if `spreadStrict` is `true`.

<hr />
### getProp
```js
getProp(props, prop, options);
```
Returns the JSXAttribute itself or undefined, indicating the prop is not present on the JSXOpeningElement.

#### Props
Object - The attributes on the visited node. (Usually `node.attributes`).
#### Prop
String - A string representation of the prop you want to check for existence.
#### Options
Object - An object representing options for existence checking
  1. `ignoreCase` - automatically set to `true`.

<hr />
### elementType
```js
elementType(node)
```
Returns the tagName associated with a JSXElement.

#### Node
Object - The visited JSXElement node object.

<hr />
### getPropValue
```js
getPropValue(prop);
```
Returns the value of a given attribute. Different types of attributes have their associated values in different properties on the object.

This function should return the most *closely* associated value with the intention of the JSX.

#### Prop
Object - The JSXAttribute collected by AST parser.

<hr />
### getLiteralPropValue
```js
getLiteralPropValue(prop);
```
Returns the value of a given attribute. Different types of attributes have their associated values in different properties on the object.

This function should return a value only if we can extract a literal value from its attribute (i.e. values that have generic types in JavaScript - strings, numbers, booleans, etc.)

#### Prop
Object - The JSXAttribute collected by AST parser.

<hr />
### propName
```js
propName(prop);
```
Returns the name associated with a JSXAttribute. For example, given `<div foo="bar" />` and the JSXAttribute for `foo`, this will return the string `"foo"`.

#### Prop
Object - The JSXAttribute collected by AST parser.