refactor!: drop through2 (#178)

Ref https://github.com/rvagg/through2#do-you-need-this
Closes #177

BREAKING CHANGES: Require node 10 and higher.

.travis.yml

@@ -1,8 +1,8 @@
 language: node_js
 node_js:
+  - 14
   - 12
   - 10
-  - 8
 script:
   - 'npm run lint'
   - 'npm run test'

bin/csv-parser

@@ -2,7 +2,7 @@
 
 const { EOL } = require('os')
 const minimist = require('minimist')
-const through = require('through2')
+const { Transform } = require('stream');
 const fs = require('fs')
 const csv = require('../')
 const pkg = require('../package.json')
@@ -80,9 +80,12 @@ if (filename === '-' || !filename) {
 }
 
 const serialize = () => {
-  return through.obj((obj, enc, cb) => {
-    cb(null, JSON.stringify(obj) + EOL)
-  })
+  return new Transform({
+    objectMode: true,
+    transform(obj, enc, cb) {
+      cb(null, JSON.stringify(obj) + EOL)
+    }
+  });
 }
 
 input

examples/transform.js

@@ -1,5 +1,5 @@
 const write = require('csv-write-stream')
-const through = require('through2')
+const { Transform } = require('stream')
 const parse = require('../')
 const path = require('path')
 const fs = require('fs')
@@ -10,7 +10,7 @@ const fs = require('fs')
 // .pipe(fs.createWriteStream('./file'))
 fs.createReadStream(path.join(__dirname, '../test/data/dummy.csv'))
   .pipe(parse())
-  .pipe(through.obj(transform))
+  .pipe(new Transform({ objectMode: true, transform }))
   .pipe(write())
   .pipe(process.stdout)
 

package.json

@@ -20,7 +20,7 @@
     "index.d.ts"
   ],
   "engines": {
-    "node": ">= 8.16.0"
+    "node": ">= 10"
   },
   "scripts": {
     "bench": "bin/bench",
@@ -32,8 +32,7 @@
     "test": "ava && tsd"
   },
   "dependencies": {
-    "minimist": "^1.2.0",
-    "through2": "^3.0.1"
+    "minimist": "^1.2.0"
   },
   "devDependencies": {
     "@commitlint/cli": "^8.2.0",