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diff --git a/deps/npm/node_modules/minipass/README.md b/deps/npm/node_modules/minipass/README.md new file mode 100644 index 0000000000..7a83c59ffd --- /dev/null +++ b/deps/npm/node_modules/minipass/README.md @@ -0,0 +1,124 @@ +# minipass + +A _very_ minimal implementation of a [PassThrough +stream](https://nodejs.org/api/stream.html#stream_class_stream_passthrough) + +[It's very +fast](https://docs.google.com/spreadsheets/d/1oObKSrVwLX_7Ut4Z6g3fZW-AX1j1-k6w-cDsrkaSbHM/edit#gid=0) +for objects, strings, and buffers. + +Supports pipe()ing (including multi-pipe() and backpressure +transmission), buffering data until either a `data` event handler or +`pipe()` is added (so you don't lose the first chunk), and most other +cases where PassThrough is a good idea. + +There is a `read()` method, but it's much more efficient to consume +data from this stream via `'data'` events or by calling `pipe()` into +some other stream. Calling `read()` requires the buffer to be +flattened in some cases, which requires copying memory. + +There is also no `unpipe()` method. Once you start piping, there is +no stopping it! + +If you set `objectMode: true` in the options, then whatever is written +will be emitted. Otherwise, it'll do a minimal amount of Buffer +copying to ensure proper Streams semantics when `read(n)` is called. + +This is not a `through` or `through2` stream. It doesn't transform +the data, it just passes it right through. If you want to transform +the data, extend the class, and override the `write()` method. Once +you're done transforming the data however you want, call +`super.write()` with the transform output. + +For an example of a stream that extends MiniPass to provide transform +capabilities, check out [minizlib](http://npm.im/minizlib). + +## USAGE + +```js +const MiniPass = require('minipass') +const mp = new MiniPass(options) // optional: { encoding } +mp.write('foo') +mp.pipe(someOtherStream) +mp.end('bar') +``` + +### collecting + +```js +mp.collect().then(all => { + // all is an array of all the data emitted + // encoding is supported in this case, so + // so the result will be a collection of strings if + // an encoding is specified, or buffers/objects if not. + // + // In an async function, you may do + // const data = await stream.collect() +}) +``` + +### iteration + +You can iterate over streams synchronously or asynchronously in +platforms that support it. + +Synchronous iteration will end when the currently available data is +consumed, even if the `end` event has not been reached. In string and +buffer mode, the data is concatenated, so unless multiple writes are +occurring in the same tick as the `read()`, sync iteration loops will +generally only have a single iteration. + +To consume chunks in this way exactly as they have been written, with +no flattening, create the stream with the `{ objectMode: true }` +option. + +```js +const mp = new Minipass({ objectMode: true }) +mp.write('a') +mp.write('b') +for (let letter of mp) { + console.log(letter) // a, b +} +mp.write('c') +mp.write('d') +for (let letter of mp) { + console.log(letter) // c, d +} +mp.write('e') +mp.end() +for (let letter of mp) { + console.log(letter) // e +} +for (let letter of mp) { + console.log(letter) // nothing +} +``` + +Asynchronous iteration will continue until the end event is reached, +consuming all of the data. + +```js +const mp = new Minipass({ encoding: 'utf8' }) + +// some source of some data +let i = 5 +const inter = setInterval(() => { + if (i --> 0) + mp.write(Buffer.from('foo\n', 'utf8')) + else { + mp.end() + clearInterval(inter) + } +}, 100) + +// consume the data with asynchronous iteration +async function consume () { + for await (let chunk of mp) { + console.log(chunk) + } + return 'ok' +} + +consume().then(res => console.log(res)) +// logs `foo\n` 5 times, and then `ok` +``` |