fix: Remove flat util fn (#136)

BREAKING CHANGE: Node 12+ supported

index.js

@@ -15,16 +15,6 @@ const stream = require('readable-stream')
 
 const getFiles = require('./get-files') // browser exclude
 
-// TODO: When Node 10 support is dropped, replace this with Array.prototype.flat
-function flat (arr1) {
-  return arr1.reduce(
-    (acc, val) => Array.isArray(val)
-      ? acc.concat(flat(val))
-      : acc.concat(val),
-    []
-  )
-}
-
 const announceList = [
   ['udp://tracker.leechers-paradise.org:6969'],
   ['udp://tracker.coppersurfer.tk:6969'],
@@ -206,7 +196,7 @@ function _parseInput (input, opts, cb) {
       cb(null, file)
     }), (err, files) => {
       if (err) return cb(err)
-      files = flat(files)
+      files = files.flat()
       cb(null, files, isSingleFileTorrent)
     })
   }
@@ -295,11 +285,11 @@ function onFiles (files, opts, cb) {
 
   if (!announceList) announceList = []
 
-  if (global.WEBTORRENT_ANNOUNCE) {
-    if (typeof global.WEBTORRENT_ANNOUNCE === 'string') {
-      announceList.push([[global.WEBTORRENT_ANNOUNCE]])
-    } else if (Array.isArray(global.WEBTORRENT_ANNOUNCE)) {
-      announceList = announceList.concat(global.WEBTORRENT_ANNOUNCE.map(u => [u]))
+  if (globalThis.WEBTORRENT_ANNOUNCE) {
+    if (typeof globalThis.WEBTORRENT_ANNOUNCE === 'string') {
+      announceList.push([[globalThis.WEBTORRENT_ANNOUNCE]])
+    } else if (Array.isArray(globalThis.WEBTORRENT_ANNOUNCE)) {
+      announceList = announceList.concat(globalThis.WEBTORRENT_ANNOUNCE.map(u => [u]))
     }
   }