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'use strict'
// Based on https://github.com/tmpvar/jsdom/blob/aa85b2abf07766ff7bf5c1f6daafb3726f2f2db5/lib/jsdom/living/blob.js
// (MIT licensed)
const Buffer = require('safe-buffer').Buffer
const BUFFER = Symbol('buffer')
const TYPE = Symbol('type')
const CLOSED = Symbol('closed')
class Blob {
constructor () {
Object.defineProperty(this, Symbol.toStringTag, {
value: 'Blob',
writable: false,
enumerable: false,
configurable: true
})
this[CLOSED] = false
this[TYPE] = ''
const blobParts = arguments[0]
const options = arguments[1]
const buffers = []
if (blobParts) {
const a = blobParts
const length = Number(a.length)
for (let i = 0; i < length; i++) {
const element = a[i]
let buffer
if (Buffer.isBuffer(element)) {
buffer = element
} else if (ArrayBuffer.isView(element)) {
buffer = Buffer.from(new Uint8Array(element.buffer, element.byteOffset, element.byteLength))
} else if (element instanceof ArrayBuffer) {
buffer = Buffer.from(new Uint8Array(element))
} else if (element instanceof Blob) {
buffer = element[BUFFER]
} else {
buffer = Buffer.from(typeof element === 'string' ? element : String(element))
}
buffers.push(buffer)
}
}
this[BUFFER] = Buffer.concat(buffers)
let type = options && options.type !== undefined && String(options.type).toLowerCase()
if (type && !/[^\u0020-\u007E]/.test(type)) {
this[TYPE] = type
}
}
get size () {
return this[CLOSED] ? 0 : this[BUFFER].length
}
get type () {
return this[TYPE]
}
get isClosed () {
return this[CLOSED]
}
slice () {
const size = this.size
const start = arguments[0]
const end = arguments[1]
let relativeStart, relativeEnd
if (start === undefined) {
relativeStart = 0
} else if (start < 0) {
relativeStart = Math.max(size + start, 0)
} else {
relativeStart = Math.min(start, size)
}
if (end === undefined) {
relativeEnd = size
} else if (end < 0) {
relativeEnd = Math.max(size + end, 0)
} else {
relativeEnd = Math.min(end, size)
}
const span = Math.max(relativeEnd - relativeStart, 0)
const buffer = this[BUFFER]
const slicedBuffer = buffer.slice(
relativeStart,
relativeStart + span
)
const blob = new Blob([], { type: arguments[2] })
blob[BUFFER] = slicedBuffer
blob[CLOSED] = this[CLOSED]
return blob
}
close () {
this[CLOSED] = true
}
}
exports = module.exports = Blob
exports.BUFFER = BUFFER
Object.defineProperty(Blob.prototype, Symbol.toStringTag, {
value: 'BlobPrototype',
writable: false,
enumerable: false,
configurable: true
})
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