feat: switch buffer to native Uint8Array (#2288)

During this effort querystring-browser library was replaced
by native UrlSearchParams.

Refs #2243

package.json

@@ -109,7 +109,6 @@
   "dependencies": {
     "@babel/runtime-corejs3": "^7.11.2",
     "btoa": "^1.2.1",
-    "buffer": "^6.0.3",
     "cookie": "~0.4.1",
     "cross-fetch": "^3.1.4",
     "deep-extend": "~0.6.0",
@@ -119,7 +118,6 @@
     "js-yaml": "^4.1.0",
     "lodash": "^4.17.21",
     "qs": "^6.9.4",
-    "querystring-browser": "^1.0.4",
     "traverse": "~0.6.6",
     "url": "~0.11.0"
   }

src/execute/oas3/style-serializer.js

@@ -1,5 +1,3 @@
-const { Buffer } = require('buffer');
-
 const isRfc3986Reserved = (char) => ":/?#[]@!$&'()*+,;=".indexOf(char) > -1;
 const isRrc3986Unreserved = (char) => /^[a-z0-9\-._~]+$/i.test(char);
 
@@ -33,7 +31,8 @@ export function encodeDisallowedCharacters(str, { escape } = {}, parse) {
         return char;
       }
 
-      const encoded = (Buffer.from(char).toJSON().data || [])
+      const encoder = new TextEncoder();
+      const encoded = Array.from(encoder.encode(char))
         .map((byte) => `0${byte.toString(16).toUpperCase()}`.slice(-2))
         .map((encodedByte) => `%${encodedByte}`)
         .join('');

src/specmap/lib/refs.js

@@ -1,6 +1,5 @@
 import 'cross-fetch/polyfill'; /* global fetch */
 import jsYaml from 'js-yaml';
-import qs from 'querystring-browser';
 import url from 'url';
 
 import lib from '.';
@@ -432,15 +431,18 @@ function unescapeJsonPointerToken(token) {
   if (typeof token !== 'string') {
     return token;
   }
-  return qs.unescape(token.replace(/~1/g, '/').replace(/~0/g, '~'));
+
+  const params = new URLSearchParams(`=${token.replace(/~1/g, '/').replace(/~0/g, '~')}`);
+  return params.get('');
 }
 
 /**
  * Escapes a JSON pointer.
  * @api public
  */
 function escapeJsonPointerToken(token) {
-  return qs.escape(token.replace(/~/g, '~0').replace(/\//g, '~1'));
+  const params = new URLSearchParams([['', token.replace(/~/g, '~0').replace(/\//g, '~1')]]);
+  return params.toString().slice(1);
 }
 
 function arrayToJsonPointer(arr) {