diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 3b6f33d..568f17a 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -31,7 +31,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        node-version: [10.x, 12.x, 14.x, 15.x]
+        node-version: [10.x, 12.x, 14.x, 16.x]
         # See supported Node.js release schedule at https://nodejs.org/en/about/releases/
     steps:
     - uses: actions/checkout@v2
diff --git a/.gitignore b/.gitignore
index bd2263a..88b3696 100644
--- a/.gitignore
+++ b/.gitignore
@@ -27,11 +27,12 @@ DerivedData
 *.xcuserstate
 project.xcworkspace
 
-# Android/IntelliJ
+# IDEs
 #
 build/
 .idea
 .gradle
+.vscode
 local.properties
 *.iml
 
diff --git a/Makefile b/Makefile
index cca59be..7e15049 100644
--- a/Makefile
+++ b/Makefile
@@ -8,9 +8,12 @@ build: build-dist build-test
 build-dist:
 	npx rollup -c
 
-build-test: test/fetch/api.spec.js
+build-test: test/fetch-api/api.spec.js
 	npx tsc
 
+browser:
+	./bin/server --exec "npx open-cli http://localhost:8000/test/fetch-api/browser/"
+
 commitlint: node_modules
 	npx commitlint --from origin/main --to HEAD --verbose
 
@@ -34,32 +37,32 @@ test: test-fetch test-module
 test-fetch: test-fetch-browser test-fetch-whatwg test-fetch-node
 
 test-fetch-browser: build
-	./test/fetch/browser/run.sh
+	./test/fetch-api/browser/run.sh
 
 test-fetch-whatwg: build
-	./test/fetch/whatwg/run.sh
+	./test/fetch-api/whatwg/run.sh
 
 test-fetch-node: build
-	./test/fetch/node/run.sh
+	./test/fetch-api/node/run.sh
 
 test-module: test-module-web-cjs test-module-web-esm test-module-node-cjs test-module-node-esm test-module-react-native
 
 test-module-web-cjs: build
-	./test/module/web.cjs/run.sh
+	./test/module-system/web.cjs/run.sh
 
 test-module-web-esm: build
-	./test/module/web.esm/run.sh
+	./test/module-system/web.esm/run.sh
 
 test-module-node-cjs: build
-	./test/module/node.cjs/run.sh
+	./test/module-system/node.cjs/run.sh
 
 test-module-node-esm: build
-	./test/module/node.esm/run.sh
+	./test/module-system/node.esm/run.sh
 
 test-module-react-native: build
-	./test/module/react-native/run.sh
+	./test/module-system/react-native/run.sh
 
 typecheck:
-	npx tsc --lib ES6 --noEmit index.d.ts ./test/fetch/api.spec.ts
+	npx tsc --lib ES6 --noEmit index.d.ts ./test/fetch-api/api.spec.ts
 
 .PHONY: all build deploy lint test test-fetch test-fetch-browser test-fetch-whatwg test-fetch-node test-module test-module-web-cjs test-module-web-esm test-module-node-cjs test-module-node-esm test-module-react-native typecheck
diff --git a/bin/server b/bin/server
index c3173d5..37dccb9 100755
--- a/bin/server
+++ b/bin/server
@@ -1,8 +1,9 @@
 #!/usr/bin/env node
+const yargs = require('yargs/yargs')
 const { spawn } = require('child_process')
 const express = require('express')
 const bodyParser = require('body-parser')
-const serveIndex = require('serve-index');
+const serveIndex = require('serve-index')
 const path = require('path')
 const app = express()
 const dir = path.join(__dirname, '..')
@@ -19,9 +20,9 @@ app.patch('/request', processRequest)
 app.delete('/request', processRequest)
 
 // This line needs to be at the end, otherwise it will block any method different than GET
-app.use(express.static(dir), serveIndex(dir, {'icons': true, view: 'details'}))
+app.use(express.static(dir), serveIndex(dir, { icons: true, view: 'details' }))
 
-function processRequest(req, res) {
+function processRequest (req, res) {
   const headers = {}
   const isDelete = req.method === 'DELETE'
 
@@ -39,39 +40,43 @@ function processRequest(req, res) {
   })
 }
 
-function processFileUrl(argv) {
-  const args = argv.slice(2)
+function processFileUrl (args) {
   const fileParamIndex = args.indexOf('-f')
+
   if (fileParamIndex > 0) {
     const fileIndex = fileParamIndex + 1
     args[fileIndex] = args[fileIndex].replace(/^\.\//, `http://localhost:${port}/`)
   }
+
   return args
 }
 
 const hostname = '127.0.0.1'
 const port = 8000
-const args = processFileUrl(process.argv)
+const { argv } = yargs(process.argv.slice(2))
 
 const server = app.listen(port, hostname, () => {
-  if (args.length === 0) {
-    console.log(`Test server listening at http://localhost:${port}`)
-    return
-  }
+  console.log(`Test server listening at http://localhost:${port}`)
 
-  const command = args[0]
-  const params = args.slice(1)
-  const child = spawn(command, params, {
-    env: {
-      ...process.env,
-      FORCE_COLOR: true // ensure mocha outputs colors on node test
-    }
-  })
+  if (argv.exec) {
+    const args = processFileUrl(argv.exec.split(' '))
+    const command = args[0]
+    const params = args.slice(1)
+    const child = spawn(command, params, {
+      env: {
+        ...process.env,
+        FORCE_COLOR: true // ensure mocha outputs colors on node test
+      }
+    })
 
-  child.stdout.pipe(process.stdout)
-  child.stderr.pipe(process.stdout)
-  child.on('exit', code => {
-    server.close()
-    process.exit(code)
-  })
+    child.stdout.pipe(process.stdout)
+    child.stderr.pipe(process.stdout)
+
+    if (argv.closeOnExec) {
+      child.on('exit', code => {
+        server.close()
+        process.exit(code)
+      })
+    }
+  }
 })
diff --git a/dist/browser-polyfill.js b/dist/browser-polyfill.js
index da6342e..11ccad1 100644
--- a/dist/browser-polyfill.js
+++ b/dist/browser-polyfill.js
@@ -528,5 +528,5 @@ var irrelevant = (function (exports) {
 
   return exports;
 
-}({}));
+})({});
 })(typeof self !== 'undefined' ? self : this);
diff --git a/dist/browser-ponyfill.js b/dist/browser-ponyfill.js
index f26eb09..f216aa3 100644
--- a/dist/browser-ponyfill.js
+++ b/dist/browser-ponyfill.js
@@ -537,7 +537,7 @@ var irrelevant = (function (exports) {
 
   return exports;
 
-}({}));
+})({});
 })(__self__);
 __self__.fetch.ponyfill = true;
 // Remove "polyfill" property added by whatwg-fetch
diff --git a/package.json b/package.json
index c3dba2c..4db780a 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "cross-fetch",
-  "version": "3.1.4",
+  "version": "3.1.5",
   "description": "Universal WHATWG Fetch API for Node, Browsers and React Native",
   "homepage": "https://github.com/lquixada/cross-fetch",
   "main": "dist/node-ponyfill.js",
@@ -24,8 +24,7 @@
     "globals": [
       "expect",
       "assert",
-      "chai",
-      "sinon"
+      "chai"
     ],
     "ignore": [
       "/dist/",
@@ -71,38 +70,38 @@
     "url": "https://github.com/lquixada/cross-fetch/issues"
   },
   "dependencies": {
-    "node-fetch": "2.6.1"
+    "node-fetch": "2.6.7"
   },
   "devDependencies": {
     "@commitlint/cli": "12.0.1",
     "@commitlint/config-conventional": "12.0.1",
-    "@types/chai": "4.2.15",
+    "@types/chai": "4.2.22",
     "@types/mocha": "8.2.2",
     "@types/node": "14.14.37",
     "body-parser": "1.19.0",
     "chai": "4.3.4",
-    "codecov": "3.8.1",
+    "codecov": "3.8.3",
     "cz-conventional-changelog": "3.3.0",
     "express": "4.17.1",
     "husky": "6.0.0",
     "lint-staged": "10.5.4",
     "mocha": "8.3.2",
     "mocha-headless-chrome": "3.1.0",
-    "nock": "13.0.11",
+    "nock": "13.1.3",
     "nyc": "15.1.0",
-    "ora": "5.4.0",
-    "rollup": "2.44.0",
+    "open-cli": "6.0.1",
+    "rollup": "2.58.0",
     "rollup-plugin-copy": "3.4.0",
     "rollup-plugin-terser": "7.0.2",
     "semver": "7.3.5",
     "serve-index": "1.9.1",
-    "sinon": "10.0.0",
-    "standard": "16.0.3",
-    "standard-version": "9.1.1",
-    "typescript": "4.2.3",
-    "webpack": "5.28.0",
-    "webpack-cli": "4.6.0",
-    "whatwg-fetch": "3.0.0"
+    "standard": "16.0.4",
+    "standard-version": "9.3.1",
+    "typescript": "4.4.4",
+    "webpack": "5.58.2",
+    "webpack-cli": "4.9.0",
+    "whatwg-fetch": "3.0.0",
+    "yargs": "16.2.0"
   },
   "files": [
     "dist",
diff --git a/test/fetch/api.spec.js b/test/fetch-api/api.spec.js
similarity index 100%
rename from test/fetch/api.spec.js
rename to test/fetch-api/api.spec.js
diff --git a/test/fetch/api.spec.ts b/test/fetch-api/api.spec.ts
similarity index 100%
rename from test/fetch/api.spec.ts
rename to test/fetch-api/api.spec.ts
diff --git a/test/fetch/browser/index.html b/test/fetch-api/browser/index.html
similarity index 86%
rename from test/fetch/browser/index.html
rename to test/fetch-api/browser/index.html
index 1d738b9..0c68368 100644
--- a/test/fetch/browser/index.html
+++ b/test/fetch-api/browser/index.html
@@ -1,5 +1,6 @@
 <!DOCTYPE html>
 <html>
+
 <head>
   <meta charset="utf-8">
   <!--
@@ -12,13 +13,12 @@
 <body>
   <div id="mocha"></div>
 
-  <script src="../../../node_modules/sinon/pkg/sinon.js"></script>
   <script src="../../../node_modules/chai/chai.js"></script>
   <script src="../../../node_modules/mocha/mocha.js"></script>
 
   <script src="../../setup.env.js"></script>
   <script src="../api.spec.js"></script>
-  <script src="../../module/module.spec.js"></script>
+  <script src="../../module-system/module.spec.js"></script>
   <script src="../../../dist/cross-fetch.js"></script>
 
   <script>
@@ -31,4 +31,5 @@
     mocha.run();
   </script>
 </body>
+
 </html>
diff --git a/test/fetch-api/browser/run.sh b/test/fetch-api/browser/run.sh
new file mode 100755
index 0000000..f7bb42c
--- /dev/null
+++ b/test/fetch-api/browser/run.sh
@@ -0,0 +1,3 @@
+#!/bin/sh
+browser="./node_modules/.bin/mocha-headless-chrome"
+./bin/server --exec "$browser -f $(dirname $0)/index.html?globals=on" --closeOnExec
diff --git a/test/fetch/node/index.js b/test/fetch-api/node/index.js
similarity index 70%
rename from test/fetch/node/index.js
rename to test/fetch-api/node/index.js
index 167b732..ce65e86 100644
--- a/test/fetch/node/index.js
+++ b/test/fetch-api/node/index.js
@@ -1,7 +1,7 @@
 require('../../../dist/node-polyfill')
 
 const addFetchSuite = require('../api.spec')
-const { addPolyfillSuite } = require('../../module/module.spec')
+const { addPolyfillSuite } = require('../../module-system/module.spec')
 
 describe('Node:Fetch', () => {
   addFetchSuite()
diff --git a/test/fetch/node/run.sh b/test/fetch-api/node/run.sh
similarity index 51%
rename from test/fetch/node/run.sh
rename to test/fetch-api/node/run.sh
index 823d062..da4d55c 100755
--- a/test/fetch/node/run.sh
+++ b/test/fetch-api/node/run.sh
@@ -1,4 +1,4 @@
 #!/bin/sh
 nyc="./node_modules/.bin/nyc"
 mocha="./node_modules/.bin/mocha"
-./bin/server $nyc $mocha $(dirname "$0")/index.js
+./bin/server --exec "$nyc $mocha $(dirname $0)/index.js" --closeOnExec
diff --git a/test/fetch/whatwg/index.html b/test/fetch-api/whatwg/index.html
similarity index 86%
rename from test/fetch/whatwg/index.html
rename to test/fetch-api/whatwg/index.html
index adfc3d2..c947c3b 100644
--- a/test/fetch/whatwg/index.html
+++ b/test/fetch-api/whatwg/index.html
@@ -1,5 +1,6 @@
 <!DOCTYPE html>
 <html>
+
 <head>
   <meta charset="utf-8">
   <!--
@@ -12,13 +13,12 @@
 <body>
   <div id="mocha"></div>
 
-  <script src="../../../node_modules/sinon/pkg/sinon.js"></script>
   <script src="../../../node_modules/chai/chai.js"></script>
   <script src="../../../node_modules/mocha/mocha.js"></script>
 
   <script src="../../setup.env.js"></script>
   <script src="../api.spec.js"></script>
-  <script src="../../module/module.spec.js"></script>
+  <script src="../../module-system/module.spec.js"></script>
   <script src="../../../dist/cross-fetch.js"></script>
 
   <script>
@@ -31,4 +31,5 @@
     mocha.run();
   </script>
 </body>
+
 </html>
diff --git a/test/fetch-api/whatwg/run.sh b/test/fetch-api/whatwg/run.sh
new file mode 100755
index 0000000..b3fcb6d
--- /dev/null
+++ b/test/fetch-api/whatwg/run.sh
@@ -0,0 +1,3 @@
+#!/bin/sh
+browser="./node_modules/.bin/mocha-headless-chrome"
+./bin/server --exec "$browser -f $(dirname $0)/index.html?globals=off" --closeOnExec
diff --git a/test/fetch/browser/run.sh b/test/fetch/browser/run.sh
deleted file mode 100755
index fbacdc8..0000000
--- a/test/fetch/browser/run.sh
+++ /dev/null
@@ -1,3 +0,0 @@
-#!/bin/sh
-browser="./node_modules/.bin/mocha-headless-chrome"
-./bin/server $browser -f "$(dirname $0)/index.html?globals=on"
diff --git a/test/fetch/whatwg/run.sh b/test/fetch/whatwg/run.sh
deleted file mode 100755
index f0a2dce..0000000
--- a/test/fetch/whatwg/run.sh
+++ /dev/null
@@ -1,3 +0,0 @@
-#!/bin/sh
-browser="./node_modules/.bin/mocha-headless-chrome"
-./bin/server $browser -f "$(dirname $0)/index.html?globals=off"
diff --git a/test/module/module.spec.js b/test/module-system/module.spec.js
similarity index 100%
rename from test/module/module.spec.js
rename to test/module-system/module.spec.js
diff --git a/test/module/node.cjs/polyfill.js b/test/module-system/node.cjs/polyfill.js
similarity index 100%
rename from test/module/node.cjs/polyfill.js
rename to test/module-system/node.cjs/polyfill.js
diff --git a/test/module/node.cjs/ponyfill.js b/test/module-system/node.cjs/ponyfill.js
similarity index 100%
rename from test/module/node.cjs/ponyfill.js
rename to test/module-system/node.cjs/ponyfill.js
diff --git a/test/module/node.cjs/run.sh b/test/module-system/node.cjs/run.sh
similarity index 100%
rename from test/module/node.cjs/run.sh
rename to test/module-system/node.cjs/run.sh
diff --git a/test/module/node.cjs/webpack.config.js b/test/module-system/node.cjs/webpack.config.js
similarity index 100%
rename from test/module/node.cjs/webpack.config.js
rename to test/module-system/node.cjs/webpack.config.js
diff --git a/test/module/node.esm/polyfill.js b/test/module-system/node.esm/polyfill.js
similarity index 100%
rename from test/module/node.esm/polyfill.js
rename to test/module-system/node.esm/polyfill.js
diff --git a/test/module/node.esm/ponyfill.js b/test/module-system/node.esm/ponyfill.js
similarity index 100%
rename from test/module/node.esm/ponyfill.js
rename to test/module-system/node.esm/ponyfill.js
diff --git a/test/module/node.esm/run.sh b/test/module-system/node.esm/run.sh
similarity index 100%
rename from test/module/node.esm/run.sh
rename to test/module-system/node.esm/run.sh
diff --git a/test/module/node.esm/webpack.config.js b/test/module-system/node.esm/webpack.config.js
similarity index 100%
rename from test/module/node.esm/webpack.config.js
rename to test/module-system/node.esm/webpack.config.js
diff --git a/test/module/react-native/index.js b/test/module-system/react-native/index.js
similarity index 100%
rename from test/module/react-native/index.js
rename to test/module-system/react-native/index.js
diff --git a/test/module/react-native/run.sh b/test/module-system/react-native/run.sh
similarity index 100%
rename from test/module/react-native/run.sh
rename to test/module-system/react-native/run.sh
diff --git a/test/module/web.cjs/polyfill.js b/test/module-system/web.cjs/polyfill.js
similarity index 100%
rename from test/module/web.cjs/polyfill.js
rename to test/module-system/web.cjs/polyfill.js
diff --git a/test/module/web.cjs/ponyfill.js b/test/module-system/web.cjs/ponyfill.js
similarity index 100%
rename from test/module/web.cjs/ponyfill.js
rename to test/module-system/web.cjs/ponyfill.js
diff --git a/test/module/web.cjs/run.sh b/test/module-system/web.cjs/run.sh
similarity index 100%
rename from test/module/web.cjs/run.sh
rename to test/module-system/web.cjs/run.sh
diff --git a/test/module/web.cjs/test.polyfill.html b/test/module-system/web.cjs/test.polyfill.html
similarity index 100%
rename from test/module/web.cjs/test.polyfill.html
rename to test/module-system/web.cjs/test.polyfill.html
diff --git a/test/module/web.cjs/test.ponyfill.html b/test/module-system/web.cjs/test.ponyfill.html
similarity index 100%
rename from test/module/web.cjs/test.ponyfill.html
rename to test/module-system/web.cjs/test.ponyfill.html
diff --git a/test/module/web.cjs/webpack.config.js b/test/module-system/web.cjs/webpack.config.js
similarity index 100%
rename from test/module/web.cjs/webpack.config.js
rename to test/module-system/web.cjs/webpack.config.js
diff --git a/test/module/web.esm/polyfill.js b/test/module-system/web.esm/polyfill.js
similarity index 100%
rename from test/module/web.esm/polyfill.js
rename to test/module-system/web.esm/polyfill.js
diff --git a/test/module/web.esm/ponyfill.js b/test/module-system/web.esm/ponyfill.js
similarity index 100%
rename from test/module/web.esm/ponyfill.js
rename to test/module-system/web.esm/ponyfill.js
diff --git a/test/module/web.esm/run.sh b/test/module-system/web.esm/run.sh
similarity index 100%
rename from test/module/web.esm/run.sh
rename to test/module-system/web.esm/run.sh
diff --git a/test/module/web.esm/test.polyfill.html b/test/module-system/web.esm/test.polyfill.html
similarity index 100%
rename from test/module/web.esm/test.polyfill.html
rename to test/module-system/web.esm/test.polyfill.html
diff --git a/test/module/web.esm/test.ponyfill.html b/test/module-system/web.esm/test.ponyfill.html
similarity index 100%
rename from test/module/web.esm/test.ponyfill.html
rename to test/module-system/web.esm/test.ponyfill.html
diff --git a/test/module/web.esm/webpack.config.js b/test/module-system/web.esm/webpack.config.js
similarity index 100%
rename from test/module/web.esm/webpack.config.js
rename to test/module-system/web.esm/webpack.config.js
diff --git a/test/module/web.cjs/test.polyfill.js b/test/module/web.cjs/test.polyfill.js
deleted file mode 100644
index 54e8c4c..0000000
--- a/test/module/web.cjs/test.polyfill.js
+++ /dev/null
@@ -1,678 +0,0 @@
-/******/ (() => { // webpackBootstrap
-/******/ 	var __webpack_modules__ = ([
-/* 0 */,
-/* 1 */
-/***/ (() => {
-
-// Enable mocha's bdd style
-mocha.setup('bdd')
-
-// Add chai's expect to the global scope
-window.expect = chai.expect
-window.assert = chai.assert
-
-if (/globals=off/.test(location.search)) {
-  // Delete native fetch api to force the polyfill installation for test purposes
-  delete window.fetch
-  delete window.Request
-  delete window.Response
-  delete window.Headers
-}
-
-
-/***/ }),
-/* 2 */
-/***/ (function() {
-
-(function(self) {
-
-var irrelevant = (function (exports) {
-
-  var support = {
-    searchParams: 'URLSearchParams' in self,
-    iterable: 'Symbol' in self && 'iterator' in Symbol,
-    blob:
-      'FileReader' in self &&
-      'Blob' in self &&
-      (function() {
-        try {
-          new Blob();
-          return true
-        } catch (e) {
-          return false
-        }
-      })(),
-    formData: 'FormData' in self,
-    arrayBuffer: 'ArrayBuffer' in self
-  };
-
-  function isDataView(obj) {
-    return obj && DataView.prototype.isPrototypeOf(obj)
-  }
-
-  if (support.arrayBuffer) {
-    var viewClasses = [
-      '[object Int8Array]',
-      '[object Uint8Array]',
-      '[object Uint8ClampedArray]',
-      '[object Int16Array]',
-      '[object Uint16Array]',
-      '[object Int32Array]',
-      '[object Uint32Array]',
-      '[object Float32Array]',
-      '[object Float64Array]'
-    ];
-
-    var isArrayBufferView =
-      ArrayBuffer.isView ||
-      function(obj) {
-        return obj && viewClasses.indexOf(Object.prototype.toString.call(obj)) > -1
-      };
-  }
-
-  function normalizeName(name) {
-    if (typeof name !== 'string') {
-      name = String(name);
-    }
-    if (/[^a-z0-9\-#$%&'*+.^_`|~]/i.test(name)) {
-      throw new TypeError('Invalid character in header field name')
-    }
-    return name.toLowerCase()
-  }
-
-  function normalizeValue(value) {
-    if (typeof value !== 'string') {
-      value = String(value);
-    }
-    return value
-  }
-
-  // Build a destructive iterator for the value list
-  function iteratorFor(items) {
-    var iterator = {
-      next: function() {
-        var value = items.shift();
-        return {done: value === undefined, value: value}
-      }
-    };
-
-    if (support.iterable) {
-      iterator[Symbol.iterator] = function() {
-        return iterator
-      };
-    }
-
-    return iterator
-  }
-
-  function Headers(headers) {
-    this.map = {};
-
-    if (headers instanceof Headers) {
-      headers.forEach(function(value, name) {
-        this.append(name, value);
-      }, this);
-    } else if (Array.isArray(headers)) {
-      headers.forEach(function(header) {
-        this.append(header[0], header[1]);
-      }, this);
-    } else if (headers) {
-      Object.getOwnPropertyNames(headers).forEach(function(name) {
-        this.append(name, headers[name]);
-      }, this);
-    }
-  }
-
-  Headers.prototype.append = function(name, value) {
-    name = normalizeName(name);
-    value = normalizeValue(value);
-    var oldValue = this.map[name];
-    this.map[name] = oldValue ? oldValue + ', ' + value : value;
-  };
-
-  Headers.prototype['delete'] = function(name) {
-    delete this.map[normalizeName(name)];
-  };
-
-  Headers.prototype.get = function(name) {
-    name = normalizeName(name);
-    return this.has(name) ? this.map[name] : null
-  };
-
-  Headers.prototype.has = function(name) {
-    return this.map.hasOwnProperty(normalizeName(name))
-  };
-
-  Headers.prototype.set = function(name, value) {
-    this.map[normalizeName(name)] = normalizeValue(value);
-  };
-
-  Headers.prototype.forEach = function(callback, thisArg) {
-    for (var name in this.map) {
-      if (this.map.hasOwnProperty(name)) {
-        callback.call(thisArg, this.map[name], name, this);
-      }
-    }
-  };
-
-  Headers.prototype.keys = function() {
-    var items = [];
-    this.forEach(function(value, name) {
-      items.push(name);
-    });
-    return iteratorFor(items)
-  };
-
-  Headers.prototype.values = function() {
-    var items = [];
-    this.forEach(function(value) {
-      items.push(value);
-    });
-    return iteratorFor(items)
-  };
-
-  Headers.prototype.entries = function() {
-    var items = [];
-    this.forEach(function(value, name) {
-      items.push([name, value]);
-    });
-    return iteratorFor(items)
-  };
-
-  if (support.iterable) {
-    Headers.prototype[Symbol.iterator] = Headers.prototype.entries;
-  }
-
-  function consumed(body) {
-    if (body.bodyUsed) {
-      return Promise.reject(new TypeError('Already read'))
-    }
-    body.bodyUsed = true;
-  }
-
-  function fileReaderReady(reader) {
-    return new Promise(function(resolve, reject) {
-      reader.onload = function() {
-        resolve(reader.result);
-      };
-      reader.onerror = function() {
-        reject(reader.error);
-      };
-    })
-  }
-
-  function readBlobAsArrayBuffer(blob) {
-    var reader = new FileReader();
-    var promise = fileReaderReady(reader);
-    reader.readAsArrayBuffer(blob);
-    return promise
-  }
-
-  function readBlobAsText(blob) {
-    var reader = new FileReader();
-    var promise = fileReaderReady(reader);
-    reader.readAsText(blob);
-    return promise
-  }
-
-  function readArrayBufferAsText(buf) {
-    var view = new Uint8Array(buf);
-    var chars = new Array(view.length);
-
-    for (var i = 0; i < view.length; i++) {
-      chars[i] = String.fromCharCode(view[i]);
-    }
-    return chars.join('')
-  }
-
-  function bufferClone(buf) {
-    if (buf.slice) {
-      return buf.slice(0)
-    } else {
-      var view = new Uint8Array(buf.byteLength);
-      view.set(new Uint8Array(buf));
-      return view.buffer
-    }
-  }
-
-  function Body() {
-    this.bodyUsed = false;
-
-    this._initBody = function(body) {
-      this._bodyInit = body;
-      if (!body) {
-        this._bodyText = '';
-      } else if (typeof body === 'string') {
-        this._bodyText = body;
-      } else if (support.blob && Blob.prototype.isPrototypeOf(body)) {
-        this._bodyBlob = body;
-      } else if (support.formData && FormData.prototype.isPrototypeOf(body)) {
-        this._bodyFormData = body;
-      } else if (support.searchParams && URLSearchParams.prototype.isPrototypeOf(body)) {
-        this._bodyText = body.toString();
-      } else if (support.arrayBuffer && support.blob && isDataView(body)) {
-        this._bodyArrayBuffer = bufferClone(body.buffer);
-        // IE 10-11 can't handle a DataView body.
-        this._bodyInit = new Blob([this._bodyArrayBuffer]);
-      } else if (support.arrayBuffer && (ArrayBuffer.prototype.isPrototypeOf(body) || isArrayBufferView(body))) {
-        this._bodyArrayBuffer = bufferClone(body);
-      } else {
-        this._bodyText = body = Object.prototype.toString.call(body);
-      }
-
-      if (!this.headers.get('content-type')) {
-        if (typeof body === 'string') {
-          this.headers.set('content-type', 'text/plain;charset=UTF-8');
-        } else if (this._bodyBlob && this._bodyBlob.type) {
-          this.headers.set('content-type', this._bodyBlob.type);
-        } else if (support.searchParams && URLSearchParams.prototype.isPrototypeOf(body)) {
-          this.headers.set('content-type', 'application/x-www-form-urlencoded;charset=UTF-8');
-        }
-      }
-    };
-
-    if (support.blob) {
-      this.blob = function() {
-        var rejected = consumed(this);
-        if (rejected) {
-          return rejected
-        }
-
-        if (this._bodyBlob) {
-          return Promise.resolve(this._bodyBlob)
-        } else if (this._bodyArrayBuffer) {
-          return Promise.resolve(new Blob([this._bodyArrayBuffer]))
-        } else if (this._bodyFormData) {
-          throw new Error('could not read FormData body as blob')
-        } else {
-          return Promise.resolve(new Blob([this._bodyText]))
-        }
-      };
-
-      this.arrayBuffer = function() {
-        if (this._bodyArrayBuffer) {
-          return consumed(this) || Promise.resolve(this._bodyArrayBuffer)
-        } else {
-          return this.blob().then(readBlobAsArrayBuffer)
-        }
-      };
-    }
-
-    this.text = function() {
-      var rejected = consumed(this);
-      if (rejected) {
-        return rejected
-      }
-
-      if (this._bodyBlob) {
-        return readBlobAsText(this._bodyBlob)
-      } else if (this._bodyArrayBuffer) {
-        return Promise.resolve(readArrayBufferAsText(this._bodyArrayBuffer))
-      } else if (this._bodyFormData) {
-        throw new Error('could not read FormData body as text')
-      } else {
-        return Promise.resolve(this._bodyText)
-      }
-    };
-
-    if (support.formData) {
-      this.formData = function() {
-        return this.text().then(decode)
-      };
-    }
-
-    this.json = function() {
-      return this.text().then(JSON.parse)
-    };
-
-    return this
-  }
-
-  // HTTP methods whose capitalization should be normalized
-  var methods = ['DELETE', 'GET', 'HEAD', 'OPTIONS', 'POST', 'PUT'];
-
-  function normalizeMethod(method) {
-    var upcased = method.toUpperCase();
-    return methods.indexOf(upcased) > -1 ? upcased : method
-  }
-
-  function Request(input, options) {
-    options = options || {};
-    var body = options.body;
-
-    if (input instanceof Request) {
-      if (input.bodyUsed) {
-        throw new TypeError('Already read')
-      }
-      this.url = input.url;
-      this.credentials = input.credentials;
-      if (!options.headers) {
-        this.headers = new Headers(input.headers);
-      }
-      this.method = input.method;
-      this.mode = input.mode;
-      this.signal = input.signal;
-      if (!body && input._bodyInit != null) {
-        body = input._bodyInit;
-        input.bodyUsed = true;
-      }
-    } else {
-      this.url = String(input);
-    }
-
-    this.credentials = options.credentials || this.credentials || 'same-origin';
-    if (options.headers || !this.headers) {
-      this.headers = new Headers(options.headers);
-    }
-    this.method = normalizeMethod(options.method || this.method || 'GET');
-    this.mode = options.mode || this.mode || null;
-    this.signal = options.signal || this.signal;
-    this.referrer = null;
-
-    if ((this.method === 'GET' || this.method === 'HEAD') && body) {
-      throw new TypeError('Body not allowed for GET or HEAD requests')
-    }
-    this._initBody(body);
-  }
-
-  Request.prototype.clone = function() {
-    return new Request(this, {body: this._bodyInit})
-  };
-
-  function decode(body) {
-    var form = new FormData();
-    body
-      .trim()
-      .split('&')
-      .forEach(function(bytes) {
-        if (bytes) {
-          var split = bytes.split('=');
-          var name = split.shift().replace(/\+/g, ' ');
-          var value = split.join('=').replace(/\+/g, ' ');
-          form.append(decodeURIComponent(name), decodeURIComponent(value));
-        }
-      });
-    return form
-  }
-
-  function parseHeaders(rawHeaders) {
-    var headers = new Headers();
-    // Replace instances of \r\n and \n followed by at least one space or horizontal tab with a space
-    // https://tools.ietf.org/html/rfc7230#section-3.2
-    var preProcessedHeaders = rawHeaders.replace(/\r?\n[\t ]+/g, ' ');
-    preProcessedHeaders.split(/\r?\n/).forEach(function(line) {
-      var parts = line.split(':');
-      var key = parts.shift().trim();
-      if (key) {
-        var value = parts.join(':').trim();
-        headers.append(key, value);
-      }
-    });
-    return headers
-  }
-
-  Body.call(Request.prototype);
-
-  function Response(bodyInit, options) {
-    if (!options) {
-      options = {};
-    }
-
-    this.type = 'default';
-    this.status = options.status === undefined ? 200 : options.status;
-    this.ok = this.status >= 200 && this.status < 300;
-    this.statusText = 'statusText' in options ? options.statusText : 'OK';
-    this.headers = new Headers(options.headers);
-    this.url = options.url || '';
-    this._initBody(bodyInit);
-  }
-
-  Body.call(Response.prototype);
-
-  Response.prototype.clone = function() {
-    return new Response(this._bodyInit, {
-      status: this.status,
-      statusText: this.statusText,
-      headers: new Headers(this.headers),
-      url: this.url
-    })
-  };
-
-  Response.error = function() {
-    var response = new Response(null, {status: 0, statusText: ''});
-    response.type = 'error';
-    return response
-  };
-
-  var redirectStatuses = [301, 302, 303, 307, 308];
-
-  Response.redirect = function(url, status) {
-    if (redirectStatuses.indexOf(status) === -1) {
-      throw new RangeError('Invalid status code')
-    }
-
-    return new Response(null, {status: status, headers: {location: url}})
-  };
-
-  exports.DOMException = self.DOMException;
-  try {
-    new exports.DOMException();
-  } catch (err) {
-    exports.DOMException = function(message, name) {
-      this.message = message;
-      this.name = name;
-      var error = Error(message);
-      this.stack = error.stack;
-    };
-    exports.DOMException.prototype = Object.create(Error.prototype);
-    exports.DOMException.prototype.constructor = exports.DOMException;
-  }
-
-  function fetch(input, init) {
-    return new Promise(function(resolve, reject) {
-      var request = new Request(input, init);
-
-      if (request.signal && request.signal.aborted) {
-        return reject(new exports.DOMException('Aborted', 'AbortError'))
-      }
-
-      var xhr = new XMLHttpRequest();
-
-      function abortXhr() {
-        xhr.abort();
-      }
-
-      xhr.onload = function() {
-        var options = {
-          status: xhr.status,
-          statusText: xhr.statusText,
-          headers: parseHeaders(xhr.getAllResponseHeaders() || '')
-        };
-        options.url = 'responseURL' in xhr ? xhr.responseURL : options.headers.get('X-Request-URL');
-        var body = 'response' in xhr ? xhr.response : xhr.responseText;
-        resolve(new Response(body, options));
-      };
-
-      xhr.onerror = function() {
-        reject(new TypeError('Network request failed'));
-      };
-
-      xhr.ontimeout = function() {
-        reject(new TypeError('Network request failed'));
-      };
-
-      xhr.onabort = function() {
-        reject(new exports.DOMException('Aborted', 'AbortError'));
-      };
-
-      xhr.open(request.method, request.url, true);
-
-      if (request.credentials === 'include') {
-        xhr.withCredentials = true;
-      } else if (request.credentials === 'omit') {
-        xhr.withCredentials = false;
-      }
-
-      if ('responseType' in xhr && support.blob) {
-        xhr.responseType = 'blob';
-      }
-
-      request.headers.forEach(function(value, name) {
-        xhr.setRequestHeader(name, value);
-      });
-
-      if (request.signal) {
-        request.signal.addEventListener('abort', abortXhr);
-
-        xhr.onreadystatechange = function() {
-          // DONE (success or failure)
-          if (xhr.readyState === 4) {
-            request.signal.removeEventListener('abort', abortXhr);
-          }
-        };
-      }
-
-      xhr.send(typeof request._bodyInit === 'undefined' ? null : request._bodyInit);
-    })
-  }
-
-  fetch.polyfill = true;
-
-  if (!self.fetch) {
-    self.fetch = fetch;
-    self.Headers = Headers;
-    self.Request = Request;
-    self.Response = Response;
-  }
-
-  exports.Headers = Headers;
-  exports.Request = Request;
-  exports.Response = Response;
-  exports.fetch = fetch;
-
-  Object.defineProperty(exports, '__esModule', { value: true });
-
-  return exports;
-
-}({}));
-})(typeof self !== 'undefined' ? self : this);
-
-
-/***/ }),
-/* 3 */
-/***/ ((module) => {
-
-/**
- * This file has all the tests needed to ensure cross-fetch is properly and equally
- * imported/required in webpack bundle for node and browser environments.
- */
-
-function addModuleSuite ({ fetch, Request, Response, Headers }) {
-  it('should have the fetch function exposed', () => {
-    expect(fetch).to.be.a('function')
-  })
-
-  it('should have the Request constructor exposed', () => {
-    expect(Request).to.be.a('function')
-  })
-
-  it('should have the Response constructor exposed', () => {
-    expect(Response).to.be.a('function')
-  })
-
-  it('should have Headers constructor exposed', () => {
-    expect(Headers).to.be.a('function')
-  })
-}
-
-function addPolyfillSuite ({ fetch }) {
-  it('should use the polyfill fetch function', () => {
-    expect(fetch.polyfill).to.equal(true)
-    expect(fetch.ponyfill).to.equal(undefined)
-  })
-}
-
-function addPonyfillSuite ({ fetch, defaultExport }) {
-  it('should use the ponyfill fetch function', () => {
-    expect(fetch.polyfill).to.equal(undefined)
-    expect(fetch.ponyfill).to.equal(true)
-  })
-
-  it('should import the fetch function as the default', () => {
-    expect(defaultExport).to.equal(fetch)
-  })
-}
-
-function addNativeSuite ({ fetch }) {
-  it('should use the native fetch function', () => {
-    expect(fetch.polyfill).to.equal(undefined)
-    expect(fetch.ponyfill).to.equal(undefined)
-  })
-}
-
-// Since this test suite needs to run on different environments,
-// we used a simplified UMD pattern here.
-if ( true && module.exports) {
-  module.exports = {
-    addModuleSuite,
-    addNativeSuite,
-    addPolyfillSuite,
-    addPonyfillSuite
-  }
-}
-
-
-/***/ })
-/******/ 	]);
-/************************************************************************/
-/******/ 	// The module cache
-/******/ 	var __webpack_module_cache__ = {};
-/******/ 	
-/******/ 	// The require function
-/******/ 	function __webpack_require__(moduleId) {
-/******/ 		// Check if module is in cache
-/******/ 		var cachedModule = __webpack_module_cache__[moduleId];
-/******/ 		if (cachedModule !== undefined) {
-/******/ 			return cachedModule.exports;
-/******/ 		}
-/******/ 		// Create a new module (and put it into the cache)
-/******/ 		var module = __webpack_module_cache__[moduleId] = {
-/******/ 			// no module.id needed
-/******/ 			// no module.loaded needed
-/******/ 			exports: {}
-/******/ 		};
-/******/ 	
-/******/ 		// Execute the module function
-/******/ 		__webpack_modules__[moduleId].call(module.exports, module, module.exports, __webpack_require__);
-/******/ 	
-/******/ 		// Return the exports of the module
-/******/ 		return module.exports;
-/******/ 	}
-/******/ 	
-/************************************************************************/
-var __webpack_exports__ = {};
-// This entry need to be wrapped in an IIFE because it need to be isolated against other modules in the chunk.
-(() => {
-__webpack_require__(1)
-__webpack_require__(2)
-const { addModuleSuite, addPolyfillSuite, addNativeSuite } = __webpack_require__(3)
-
-if (/globals=off/.test(location.search)) {
-  describe('Browser:Polyfill:Require:Webpack', () => {
-    addModuleSuite({ fetch, Request, Response, Headers })
-    addPolyfillSuite({ fetch })
-  })
-} else {
-  describe('Browser:Native:Require:Webpack', () => {
-    addModuleSuite({ fetch, Request, Response, Headers })
-    addNativeSuite({ fetch })
-  })
-}
-
-mocha.checkLeaks()
-mocha.run()
-
-})();
-
-/******/ })()
-;
\ No newline at end of file
diff --git a/tsconfig.json b/tsconfig.json
index a475630..cd8a962 100644
--- a/tsconfig.json
+++ b/tsconfig.json
@@ -70,6 +70,6 @@
   },
   "files": [
     "./index.d.ts",
-    "./test/fetch/api.spec.ts"
+    "test/fetch-api/api.spec.ts"
   ]
 }