power-assert-context-traversal

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[![NPM version][npm-image]][npm-url]
[![License][license-image]][license-url]

EventEmitter of powerAssertContext object provided by power-assert at runtime.

API
---------------------------------------

$3

Create EventEmitter of powerAssertContext object, having structure below.

``javascript
{
source: {
content: 'assert(foo === bar)',
filepath: 'test/some_test.js',
line: 1,
ast: '### JSON representation of AST nodes ###',
tokens: '### JSON representation of AST tokens ###',
visitorKeys: '### JSON representation of AST visitor keys ###'
},
args: [
{
value: false,
events: [
{
value: "FOO",
espath: "arguments/0/left"
},
{
value: "BAR",
espath: "arguments/0/right"
},
{
value: false,
espath: "arguments/0"
}
]
}
]
}
`

$3

Fire events while traversing AST tree in powerAssertContext.

$3


#### traversal.on('start', function (powerAssertContext) {})

Called once when traversal starts. Argument is the powerAssertContext object under traversal.

#### traversal.on('data', function (esNode) {})

Called for each Node of AST in powerAssertContext. Argument is a EsNode object, having structure below.

`javascript
{
espath: 'arguments/0',
parent: '### parent esNode reference unless root ###',
key: 0,
node: {
type: 'BinaryExpression',
operator: '===',
left: { type: 'Identifier', name: 'foo', range: [ 7, 10 ] },
right: { type: 'Identifier', name: 'bar', range: [ 15, 18 ] },
range: [ 7, 18 ]
},
code: 'foo === bar',
value: false,
isCaptured: true,
range: [ 11, 14 ] // range of operator
};
`

`javascript
{
espath: 'arguments/0/right',
parent: '### parent esNode reference unless root ###',
key: 'right',
node: { type: 'Identifier', name: 'bar', range: [ 15, 18 ] },
code: 'bar',
value: 'BAR',
isCaptured: true,
range: [ 15, 18 ]
};
`

#### traversal.on('end', function () {})

Called once when traversal ends.

INSTALL
---------------------------------------

`sh
$ npm install --save-dev power-assert-context-traversal
``

AUTHOR
---------------------------------------
* Takuto Wada

LICENSE
---------------------------------------
Licensed under the MIT license.

[power-assert-url]: https://github.com/power-assert-js/power-assert
[power-assert-banner]: https://raw.githubusercontent.com/power-assert-js/power-assert-js-logo/master/banner/banner-official-fullcolor.png

[travis-url]: https://travis-ci.org/twada/power-assert-runtime
[travis-image]: https://secure.travis-ci.org/twada/power-assert-runtime.svg?branch=master

[npm-url]: https://npmjs.org/package/power-assert-context-traversal
[npm-image]: https://badge.fury.io/js/power-assert-context-traversal.svg

[license-url]: https://github.com/twada/power-assert-runtime/blob/master/LICENSE
[license-image]: https://img.shields.io/badge/license-MIT-brightgreen.svg