Add Typescript definitions (#138)

* Add Typescript definitions
* Add test file for TS

index.d.ts

@@ -0,0 +1,186 @@
+declare class Pjax {
+  constructor(options?: Partial<Pjax.IOptions>);
+
+  static switches: {
+    [key in DefaultSwitches]: Pjax.Switch
+  };
+
+  /**
+   * Checks if Pjax is supported by the environment.
+   */
+  static isSupported: () => boolean;
+
+  log: VoidFunction;
+
+  getElements(el: Element | Document): NodeListOf<Element>;
+
+  parseDOM(el: Element | Document): void;
+
+  refresh: ElementFunction;
+
+  reload: VoidFunction;
+
+  attachLink(el: HTMLAnchorElement): void;
+
+  attachForm(el: HTMLFormElement): void;
+
+  forEachSelectors(cb: ElementFunction, context: Pjax, DOMcontext?: Element | Document): void;
+
+  switchesSelectors(selectors: string[], fromEl: Element | Document, toEl: Element | Document, options: Pjax.IOptions): void;
+
+  latestChance(href: string): void;
+
+  onSwitch: VoidFunction;
+
+  /**
+   * Loads the HTML from the response into the DOM.
+   *
+   * @param {string} html
+   * @param {Pjax.IOptions} options
+   */
+  loadContent(html: string, options: Pjax.IOptions): void;
+
+  /**
+   * Aborts an ongoing XHR request.
+   *
+   * @param {XMLHttpRequest} request
+   */
+  abortRequest(request: XMLHttpRequest): void;
+
+  /**
+   * Makes the XHR request.
+   *
+   * @param {string} location The URI for the request.
+   * @param {Pjax.IOptions | null} options
+   * @param {(requestText: string, request: XMLHttpRequest, href: string) => void} callback The callback to call when
+   * the response is received. The signature should match that of <code>handleResponse</code>.
+   * @returns {XMLHttpRequest}
+   */
+  doRequest(location: string, options: Pjax.IOptions | null,
+            callback: (requestText: string, request: XMLHttpRequest, href: string) => void): XMLHttpRequest;
+
+  /**
+   * Saves the state, updates the URL if there were any redirects, then calls loadContent().
+   *
+   * @param {string} requestText The raw text of the response. Same as <code>request.responseText</code>.
+   * @param {XMLHttpRequest} request The XHR object.
+   * @param {string} href The original URI used to initiate the request.
+   */
+  handleResponse(requestText: string, request: XMLHttpRequest, href: string): void;
+
+  /**
+   * Initiates the request by calling <code>doRequest()</code>.
+   * @param {string} href
+   * @param {Pjax.IOptions} options
+   */
+  loadUrl(href: string, options?: Pjax.IOptions): void;
+
+  /**
+   * Called after all switches complete (even async).
+   */
+  afterAllSwitches: VoidFunction;
+
+  /**
+   * Allows reassignment of existing prototype functions to be able to do something before calling the original function.
+   * For example:
+   *
+   * <pre>
+   *   pjax._handleResponse = pjax.handleResponse;
+   *   pjax.handleResponse = (requestText: string, request: XMLHttpRequest, href: string) => {
+   *     return pjax._handleResponse(requestText, request, href);
+   *   }
+   * </pre>
+   */
+  [key: string]: Function;
+}
+
+declare namespace Pjax {
+  export interface IOptions {
+    /**
+     * CSS selector to use to retrieve links to apply Pjax to.
+     */
+    elements: string;
+
+    /**
+     * CSS selectors for the elements to replace.
+     */
+    selectors: string[];
+
+    /**
+     * Objects containing callbacks that can be used to switch old elements with new elements.
+     * Keys should be one of the defined selectors.
+     */
+    switches: StringKeyedObject<Switch>;
+
+    /**
+     * These are options that can be used during switches.
+     * Keys should be one of the defined selectors.
+     */
+    switchesOptions: StringKeyedObject;
+
+    /**
+     * Enable the use of pushState(). Disabling this will prevent Pjax from updating browser history.
+     * Internally, this option is used when a popstate event triggers Pjax (to not pushState() again).
+     */
+    history: boolean;
+
+    /**
+     * Function that allows you to add behavior for analytics.
+     * By default it tries to track a pageview with Google Analytics (if it exists on the page).
+     * It's called every time a page is switched, even for history navigation.
+     * Set to false to disable this behavior.
+     */
+    analytics: Function | false;
+
+    /**
+     * When set to an integer, this is the value (in px from the top of the page) to scroll to when a page is switched.
+     * When set to an array of 2 integers ([x, y]), this is the value to scroll both horizontally and vertically.
+     * Set this to false to disable scrolling, which will mean the page will stay in that same position it was before
+     * loading the new elements.
+     */
+    scrollTo: number | [number, number] | false;
+
+    /**
+     * When set to true, attempt to restore the scroll position when navigating backwards or forwards.
+     */
+    scrollRestoration: boolean;
+
+    /**
+     * When set to true, append a timestamp query string segment to the requested URLs in order to skip browser cache.
+     */
+    cacheBust: boolean;
+
+    /**
+     * Enables verbose mode.
+     */
+    debug: boolean;
+
+    /**
+     * The timeout in milliseconds for the XHR requests. Set to 0 to disable the timeout.
+     */
+    timeout: number;
+
+    /**
+     * When set to true, clicking on a link that points to the current URL will trigger a full page reload.
+     * (Note that if cacheBust is set to true, the code that checks if the href is the same as the current page's URL
+     * will not work, due to the query string appended to force a cache bust).
+     */
+    currentUrlFullReload: boolean;
+  }
+
+  export type Switch = (oldEl: Element, newEl: Element, options?: IOptions, switchesOptions?: StringKeyedObject) => void;
+}
+
+interface StringKeyedObject<T = any> {
+  [key: string]: T
+}
+
+type ElementFunction = (el: Element) => void;
+
+declare enum DefaultSwitches {
+  innerHTML = "innerHTML",
+  ouetrHTML = "outerHTML",
+  sideBySide = "sideBySide"
+}
+
+export = Pjax;