Axios ES2017 (#4787)

* Added AxiosHeaders class;

* Fixed README.md href;

* Fixed a potential bug with headers normalization;

* Fixed a potential bug with headers normalization;
Refactored accessor building routine;
Refactored default transforms;
Removed `normalizeHeaderName` helper;

* Added `Content-Length` accessor;
Added missed `has` accessor to TS types;

* Added `AxiosTransformStream` class;
Added progress capturing ability for node.js environment;
Added `maxRate` option to limit the data rate in node.js environment;
Refactored event handled by `onUploadProgress` && `onDownloadProgress` listeners in browser environment;
Added progress & data rate tests for the http adapter;
Added response stream aborting test;
Added a manual progress capture test for the browser;
Updated TS types;
Added TS tests;
Refactored request abort logic for the http adapter;
Added ability to abort the response stream;

* Remove `stream/promises` & `timers/promises` modules usage in tests;

* Use `abortcontroller-polyfill`;

* Fixed AxiosTransformStream dead-lock in legacy node versions;
Fixed CancelError emitting in streams;

* Reworked AxiosTransformStream internal logic to optimize memory consumption;
Added throwing an error if the request stream was silently destroying (without error) Refers to #3966;

* Treat the destruction of the request stream as a cancellation of the request;
Fixed tests;

* Emit `progress` event in the next tick;

* Initial refactoring;

* Refactored Mocha tests to use ESM;

* Refactored Karma tests to use rollup preprocessor & ESM;
Replaced grunt with gulp;
Improved dev scripts;
Added Babel for rollup build;

* Added default commonjs package export for Node build;
Added automatic contributors list generator for package.json;

Co-authored-by: Jay <jasonsaayman@gmail.com>

lib/cancel/CancelToken.js

@@ -1,6 +1,6 @@
 'use strict';
 
-var CanceledError = require('./CanceledError');
+import CanceledError from './CanceledError.js';
 
 /**
  * A `CancelToken` is an object that can be used to request cancellation of an operation.
@@ -9,111 +9,113 @@ var CanceledError = require('./CanceledError');
  *
  * @returns {CancelToken}
  */
-function CancelToken(executor) {
-  if (typeof executor !== 'function') {
-    throw new TypeError('executor must be a function.');
-  }
-
-  var resolvePromise;
-
-  this.promise = new Promise(function promiseExecutor(resolve) {
-    resolvePromise = resolve;
-  });
-
-  var token = this;
-
-  // eslint-disable-next-line func-names
-  this.promise.then(function(cancel) {
-    if (!token._listeners) return;
-
-    var i = token._listeners.length;
-
-    while (i-- > 0) {
-      token._listeners[i](cancel);
+class CancelToken {
+  constructor(executor) {
+    if (typeof executor !== 'function') {
+      throw new TypeError('executor must be a function.');
     }
-    token._listeners = null;
-  });
 
-  // eslint-disable-next-line func-names
-  this.promise.then = function(onfulfilled) {
-    var _resolve;
+    let resolvePromise;
+
+    this.promise = new Promise(function promiseExecutor(resolve) {
+      resolvePromise = resolve;
+    });
+
+    const token = this;
+
     // eslint-disable-next-line func-names
-    var promise = new Promise(function(resolve) {
-      token.subscribe(resolve);
-      _resolve = resolve;
-    }).then(onfulfilled);
+    this.promise.then(cancel => {
+      if (!token._listeners) return;
 
-    promise.cancel = function reject() {
-      token.unsubscribe(_resolve);
+      let i = token._listeners.length;
+
+      while (i-- > 0) {
+        token._listeners[i](cancel);
+      }
+      token._listeners = null;
+    });
+
+    // eslint-disable-next-line func-names
+    this.promise.then = onfulfilled => {
+      let _resolve;
+      // eslint-disable-next-line func-names
+      const promise = new Promise(resolve => {
+        token.subscribe(resolve);
+        _resolve = resolve;
+      }).then(onfulfilled);
+
+      promise.cancel = function reject() {
+        token.unsubscribe(_resolve);
+      };
+
+      return promise;
     };
 
-    return promise;
-  };
+    executor(function cancel(message, config, request) {
+      if (token.reason) {
+        // Cancellation has already been requested
+        return;
+      }
 
-  executor(function cancel(message, config, request) {
-    if (token.reason) {
-      // Cancellation has already been requested
+      token.reason = new CanceledError(message, config, request);
+      resolvePromise(token.reason);
+    });
+  }
+
+  /**
+   * Throws a `CanceledError` if cancellation has been requested.
+   */
+  throwIfRequested() {
+    if (this.reason) {
+      throw this.reason;
+    }
+  }
+
+  /**
+   * Subscribe to the cancel signal
+   */
+
+  subscribe(listener) {
+    if (this.reason) {
+      listener(this.reason);
       return;
     }
 
-    token.reason = new CanceledError(message, config, request);
-    resolvePromise(token.reason);
-  });
+    if (this._listeners) {
+      this._listeners.push(listener);
+    } else {
+      this._listeners = [listener];
+    }
+  }
+
+  /**
+   * Unsubscribe from the cancel signal
+   */
+
+  unsubscribe(listener) {
+    if (!this._listeners) {
+      return;
+    }
+    const index = this._listeners.indexOf(listener);
+    if (index !== -1) {
+      this._listeners.splice(index, 1);
+    }
+  }
+
+  /**
+   * Returns an object that contains a new `CancelToken` and a function that, when called,
+   * cancels the `CancelToken`.
+   */
+  static source() {
+    let cancel;
+    const token = new CancelToken(function executor(c) {
+      cancel = c;
+    });
+    return {
+      token,
+      cancel
+    };
+  }
 }
 
-/**
- * Throws a `CanceledError` if cancellation has been requested.
- */
-CancelToken.prototype.throwIfRequested = function throwIfRequested() {
-  if (this.reason) {
-    throw this.reason;
-  }
-};
-
-/**
- * Subscribe to the cancel signal
- */
-
-CancelToken.prototype.subscribe = function subscribe(listener) {
-  if (this.reason) {
-    listener(this.reason);
-    return;
-  }
-
-  if (this._listeners) {
-    this._listeners.push(listener);
-  } else {
-    this._listeners = [listener];
-  }
-};
-
-/**
- * Unsubscribe from the cancel signal
- */
-
-CancelToken.prototype.unsubscribe = function unsubscribe(listener) {
-  if (!this._listeners) {
-    return;
-  }
-  var index = this._listeners.indexOf(listener);
-  if (index !== -1) {
-    this._listeners.splice(index, 1);
-  }
-};
-
-/**
- * Returns an object that contains a new `CancelToken` and a function that, when called,
- * cancels the `CancelToken`.
- */
-CancelToken.source = function source() {
-  var cancel;
-  var token = new CancelToken(function executor(c) {
-    cancel = c;
-  });
-  return {
-    token: token,
-    cancel: cancel
-  };
-};
-
-module.exports = CancelToken;
+export default CancelToken;

lib/cancel/CanceledError.js

@@ -1,7 +1,7 @@
 'use strict';
 
-var AxiosError = require('../core/AxiosError');
-var utils = require('../utils');
+import AxiosError from '../core/AxiosError.js';
+import utils from '../utils.js';
 
 /**
  * A `CanceledError` is an object that is thrown when an operation is canceled.
@@ -22,4 +22,4 @@ utils.inherits(CanceledError, AxiosError, {
   __CANCEL__: true
 });
 
-module.exports = CanceledError;
+export default CanceledError;

lib/cancel/isCancel.js

@@ -1,5 +1,5 @@
 'use strict';
 
-module.exports = function isCancel(value) {
+export default function isCancel(value) {
   return !!(value && value.__CANCEL__);
-};
+}