Files
xen-orchestra/@vates/read-chunk/index.test.js
2023-04-08 10:53:05 +02:00

148 lines
4.4 KiB
JavaScript

'use strict'
const { describe, it } = require('test')
const assert = require('node:assert').strict
const { Readable } = require('stream')
const { readChunk, readChunkStrict, skip, skipStrict } = require('./')
const makeStream = it => Readable.from(it, { objectMode: false })
makeStream.obj = Readable.from
const rejectionOf = promise =>
promise.then(
value => {
throw value
},
error => error
)
const makeErrorTests = fn => {
it('rejects if the stream errors', async () => {
const error = new Error()
const stream = makeStream([])
const pError = rejectionOf(fn(stream, 10))
stream.destroy(error)
assert.strict(await pError, error)
})
// only supported for Node >= 18
if (process.versions.node.split('.')[0] >= 18) {
it('rejects if the stream has already errored', async () => {
const error = new Error()
const stream = makeStream([])
await new Promise(resolve => {
stream.once('error', resolve).destroy(error)
})
assert.strict(await rejectionOf(fn(stream, 10)), error)
})
}
}
describe('readChunk', () => {
it('rejects if size is less than or equal to 0', async () => {
const error = await rejectionOf(readChunk(makeStream([]), 0))
assert.strictEqual(error.code, 'ERR_ASSERTION')
})
it('rejects if size is greater than or equal to 1 GiB', async () => {
const error = await rejectionOf(readChunk(makeStream([]), 1024 * 1024 * 1024))
assert.strictEqual(error.code, 'ERR_ASSERTION')
})
makeErrorTests(readChunk)
it('returns null if stream is empty', async () => {
assert.strictEqual(await readChunk(makeStream([])), null)
})
it('returns null if the stream is already ended', async () => {
const stream = await makeStream([])
await readChunk(stream)
assert.strictEqual(await readChunk(stream), null)
})
describe('with binary stream', () => {
it('returns the first chunk of data', async () => {
assert.deepEqual(await readChunk(makeStream(['foo', 'bar'])), Buffer.from('foo'))
})
it('returns a chunk of the specified size (smaller than first)', async () => {
assert.deepEqual(await readChunk(makeStream(['foo', 'bar']), 2), Buffer.from('fo'))
})
it('returns a chunk of the specified size (larger than first)', async () => {
assert.deepEqual(await readChunk(makeStream(['foo', 'bar']), 4), Buffer.from('foob'))
})
it('returns less data if stream ends', async () => {
assert.deepEqual(await readChunk(makeStream(['foo', 'bar']), 10), Buffer.from('foobar'))
})
})
describe('with object stream', () => {
it('returns the first chunk of data verbatim', async () => {
const chunks = [{}, {}]
assert.strictEqual(await readChunk(makeStream.obj(chunks)), chunks[0])
})
})
})
describe('readChunkStrict', function () {
it('throws if stream is empty', async () => {
const error = await rejectionOf(readChunkStrict(makeStream([])))
assert(error instanceof Error)
assert.strictEqual(error.message, 'stream has ended without data')
assert.strictEqual(error.chunk, undefined)
})
it('throws if stream ends with not enough data', async () => {
const error = await rejectionOf(readChunkStrict(makeStream(['foo', 'bar']), 10))
assert(error instanceof Error)
assert.strictEqual(error.message, 'stream has ended with not enough data (actual: 6, expected: 10)')
assert.deepEqual(error.chunk, Buffer.from('foobar'))
})
})
describe('skip', function () {
makeErrorTests(skip)
it('returns 0 if size is 0', async () => {
assert.strictEqual(await skip(makeStream(['foo']), 0), 0)
})
it('returns 0 if the stream is already ended', async () => {
const stream = await makeStream([])
await readChunk(stream)
assert.strictEqual(await skip(stream, 10), 0)
})
it('skips a number of bytes', async () => {
const stream = makeStream('foo bar')
assert.strictEqual(await skip(stream, 4), 4)
assert.deepEqual(await readChunk(stream, 4), Buffer.from('bar'))
})
it('returns less size if stream ends', async () => {
assert.deepEqual(await skip(makeStream('foo bar'), 10), 7)
})
})
describe('skipStrict', function () {
it('throws if stream ends with not enough data', async () => {
const error = await rejectionOf(skipStrict(makeStream('foo bar'), 10))
assert(error instanceof Error)
assert.strictEqual(error.message, 'stream has ended with not enough data (actual: 7, expected: 10)')
assert.deepEqual(error.bytesSkipped, 7)
})
})