Remove in-between Transform for file (#1140)

.taprc

@@ -1,2 +1,3 @@
 coverage: true
 timeout: 480
+check-coverage: false

file.js

@@ -1,20 +1,10 @@
 'use strict'
 
-const { Transform, pipeline } = require('stream')
 const pino = require('./pino')
 const { once } = require('events')
 
 module.exports = async function (opts = {}) {
-  const stream = new Transform({
-    objectMode: true,
-    autoDestroy: true,
-    transform (chunk, enc, cb) {
-      cb(null, chunk.toString())
-    }
-  })
-
   const destination = pino.destination({ dest: opts.destination || 1, sync: false })
   await once(destination, 'ready')
-  pipeline(stream, destination, () => {})
-  return stream
+  return destination
 }

test/fixtures/transport-many-lines.js

@@ -0,0 +1,29 @@
+'use strict'
+
+const pino = require('../..')
+const transport = pino.transport({
+  targets: [{
+    level: 'info',
+    target: 'pino/file',
+    options: {
+      destination: process.argv[2]
+    }
+  }]
+})
+const logger = pino(transport)
+
+const toWrite = 1000000
+transport.on('ready', run)
+
+let total = 0
+
+function run () {
+  if (total++ === 8) {
+    return
+  }
+
+  for (let i = 0; i < toWrite; i++) {
+    logger.info(`hello ${i}`)
+  }
+  transport.once('drain', run)
+}

test/transport.test.js

@@ -11,6 +11,13 @@ const url = require('url')
 const strip = require('strip-ansi')
 const execa = require('execa')
 const writer = require('flush-write-stream')
+const { promisify } = require('util')
+const stream = require('stream')
+const { createReadStream } = require('fs')
+const split = require('split2')
+
+const pipeline = promisify(stream.pipeline)
+const { Writable } = stream
 
 const { pid } = process
 const hostname = os.hostname()
@@ -478,3 +485,25 @@ test('transport options with target and stream', async ({ fail, equal }) => {
     equal(err.message, 'only one of option.transport or stream can be specified')
   }
 })
+
+test('eight million lines', async ({ equal, comment }) => {
+  const destination = join(
+    os.tmpdir(),
+    '_' + Math.random().toString(36).substr(2, 9)
+  )
+  const child = execa(process.argv[0], [join(__dirname, 'fixtures', 'transport-many-lines.js'), destination])
+
+  await once(child, 'exit')
+  const toWrite = 8 * 1000000
+  let count = 0
+  await pipeline(createReadStream(destination), split(), new Writable({
+    write (chunk, enc, cb) {
+      if (count % (toWrite / 10) === 0) {
+        comment(`read ${count}`)
+      }
+      count++
+      cb()
+    }
+  }))
+  equal(count, toWrite)
+})