[major] Drop support for Node.js < 10

.github/workflows/ci.yml

@@ -10,7 +10,6 @@ jobs:
     strategy:
       matrix:
         node:
-          - 8
           - 10
           - 12
           - 14

appveyor.yml

@@ -4,7 +4,6 @@ environment:
     - nodejs_version: '14'
     - nodejs_version: '12'
     - nodejs_version: '10'
-    - nodejs_version: '8'
 platform:
   - x86
 matrix:

lib/buffer-util.js

@@ -52,9 +52,7 @@ function _mask(source, mask, output, offset, length) {
  * @public
  */
 function _unmask(buffer, mask) {
-  // Required until https://github.com/nodejs/node/issues/9006 is resolved.
-  const length = buffer.length;
-  for (let i = 0; i < length; i++) {
+  for (let i = 0; i < buffer.length; i++) {
     buffer[i] ^= mask[i & 3];
   }
 }
@@ -103,19 +101,18 @@ function toBuffer(data) {
 
 try {
   const bufferUtil = require('bufferutil');
-  const bu = bufferUtil.BufferUtil || bufferUtil;
 
   module.exports = {
     concat,
     mask(source, mask, output, offset, length) {
       if (length < 48) _mask(source, mask, output, offset, length);
-      else bu.mask(source, mask, output, offset, length);
+      else bufferUtil.mask(source, mask, output, offset, length);
     },
     toArrayBuffer,
     toBuffer,
     unmask(buffer, mask) {
       if (buffer.length < 32) _unmask(buffer, mask);
-      else bu.unmask(buffer, mask);
+      else bufferUtil.unmask(buffer, mask);
     }
   };
 } catch (e) /* istanbul ignore next */ {

lib/permessage-deflate.js

@@ -4,7 +4,7 @@ const zlib = require('zlib');
 
 const bufferUtil = require('./buffer-util');
 const Limiter = require('./limiter');
-const { kStatusCode, NOOP } = require('./constants');
+const { kStatusCode } = require('./constants');
 
 const TRAILER = Buffer.from([0x00, 0x00, 0xff, 0xff]);
 const kPerMessageDeflate = Symbol('permessage-deflate');
@@ -418,13 +418,6 @@ class PerMessageDeflate {
       this._deflate[kTotalLength] = 0;
       this._deflate[kBuffers] = [];
 
-      //
-      // An `'error'` event is emitted, only on Node.js < 10.0.0, if the
-      // `zlib.DeflateRaw` instance is closed while data is being processed.
-      // This can happen if `PerMessageDeflate#cleanup()` is called at the wrong
-      // time due to an abnormal WebSocket closure.
-      //
-      this._deflate.on('error', NOOP);
       this._deflate.on('data', deflateOnData);
     }
 

lib/validation.js

@@ -106,12 +106,7 @@ function _isValidUTF8(buf) {
 }
 
 try {
-  let isValidUTF8 = require('utf-8-validate');
-
-  /* istanbul ignore if */
-  if (typeof isValidUTF8 === 'object') {
-    isValidUTF8 = isValidUTF8.Validation.isValidUTF8; // utf-8-validate@<3.0.0
-  }
+  const isValidUTF8 = require('utf-8-validate');
 
   module.exports = {
     isValidStatusCode,

package.json

@@ -18,7 +18,7 @@
   "main": "index.js",
   "browser": "browser.js",
   "engines": {
-    "node": ">=8.3.0"
+    "node": ">=10.0.0"
   },
   "files": [
     "browser.js",