Use buffer-from module for compatibility (fixes TypeStrong#608)

package.json

@@ -49,6 +49,7 @@
   "homepage": "https://github.com/TypeStrong/ts-node",
   "devDependencies": {
     "@types/arrify": "^1.0.1",
+    "@types/buffer-from": "^1.1.0",
     "@types/chai": "^4.0.4",
     "@types/diff": "^3.2.1",
     "@types/minimist": "^1.2.0",
@@ -74,6 +75,7 @@
   },
   "dependencies": {
     "arrify": "^1.0.0",
+    "buffer-from": "^1.1.0",
     "diff": "^3.1.0",
     "make-error": "^1.1.1",
     "minimist": "^1.2.0",

src/index.ts

@@ -6,6 +6,7 @@ import mkdirp = require('mkdirp')
 import crypto = require('crypto')
 import yn = require('yn')
 import arrify = require('arrify')
+import bufferFrom = require('buffer-from')
 import { BaseError } from 'make-error'
 import * as util from 'util'
 import * as _ts from 'typescript'
@@ -557,7 +558,7 @@ function readThrough (
  * Update the output remapping the source map.
  */
 function updateOutput (outputText: string, fileName: string, sourceMap: string, getExtension: (fileName: string) => string) {
-  const base64Map = Buffer.from(updateSourceMap(sourceMap, fileName), 'utf8').toString('base64')
+  const base64Map = bufferFrom(updateSourceMap(sourceMap, fileName), 'utf8').toString('base64')
   const sourceMapContent = `data:application/json;charset=utf-8;base64,${base64Map}`
   const sourceMapLength = `${basename(fileName)}.map`.length + (getExtension(fileName).length - extname(fileName).length)