fix: Unable to navigate on server without default index support (#1372)

* Fix: Cannot serve off `/.../index.html`

Docsify must be hosted on a server that supports a default directory
index (i.e. maps `/.../` -> `/.../index.html`).

Some platforms do not support this, however. For example, HTML apps
hosted on the popular game/software platform, Itch.io.

This change supports hosting Docsify off an explicit path file, such as
`/index.html`. It does this by:

 1. Adding handling for paths like `index.html#/blah`, and
 2. Normalising paths with fragments back to markdown paths

For example, `http://example.org/index.html#/blah` would be mapped to
`http://example.org/blah.md`.

This fixes:

https://github.com/docsifyjs/docsify/issues/427

* Add end-to-end test for index file hosting

* Add code comments for explicit file changes

* Add additional tests for index file hosting

* Add additional tests for index file hosting

* [wip] Attempt to switch tests to Jest

* Add e2e test for new Jest test framework

* Verify sidebar links use file hosting

* Fix: endsWith() not supported for IE11

* Refactor: utility method moved to utility file

* Fix IE11 error from use of String.includes()

Co-authored-by: John Hildenbiddle <jhildenbiddle@users.noreply.github.com>

src/core/router/history/hash.js

@@ -1,13 +1,12 @@
 import { noop } from '../../util/core';
 import { on } from '../../util/dom';
-import { parseQuery, cleanPath, replaceSlug } from '../util';
+import { parseQuery, cleanPath, replaceSlug, endsWith } from '../util';
 import { History } from './base';
 
 function replaceHash(path) {
   const i = location.href.indexOf('#');
   location.replace(location.href.slice(0, i >= 0 ? i : 0) + '#' + path);
 }
-
 export class HashHistory extends History {
   constructor(config) {
     super(config);
@@ -18,7 +17,15 @@ export class HashHistory extends History {
     const path = window.location.pathname || '';
     const base = this.config.basePath;
 
-    return /^(\/|https?:)/g.test(base) ? base : cleanPath(path + '/' + base);
+    // This handles the case where Docsify is served off an
+    // explicit file path, i.e.`/base/index.html#/blah`. This
+    // prevents the `/index.html` part of the URI from being
+    // remove during routing.
+    // See here: https://github.com/docsifyjs/docsify/pull/1372
+    const basePath = endsWith(path, '.html')
+      ? path + '#/' + base
+      : path + '/' + base;
+    return /^(\/|https?:)/g.test(base) ? base : cleanPath(basePath);
   }
 
   getCurrentPath() {

src/core/router/util.js

@@ -76,10 +76,44 @@ export const resolvePath = cached(path => {
   return '/' + resolved.join('/');
 });
 
+/**
+ * Normalises the URI path to handle the case where Docsify is
+ * hosted off explicit files, i.e. /index.html. This function
+ * eliminates any path segments that contain `#` fragments.
+ *
+ * This is used to map browser URIs to markdown file sources.
+ *
+ * For example:
+ *
+ * http://example.org/base/index.html#/blah
+ *
+ * would be mapped to:
+ *
+ * http://example.org/base/blah.md.
+ *
+ * See here for more information:
+ *
+ * https://github.com/docsifyjs/docsify/pull/1372
+ *
+ * @param {string} path The URI path to normalise
+ * @return {string} { path, query }
+ */
+
+function normaliseFragment(path) {
+  return path
+    .split('/')
+    .filter(p => p.indexOf('#') === -1)
+    .join('/');
+}
+
 export function getPath(...args) {
-  return cleanPath(args.join('/'));
+  return cleanPath(args.map(normaliseFragment).join('/'));
 }
 
 export const replaceSlug = cached(path => {
   return path.replace('#', '?id=');
 });
+
+export function endsWith(str, suffix) {
+  return str.indexOf(suffix, str.length - suffix.length) !== -1;
+}

test/e2e/index-file.test.js

@@ -0,0 +1,28 @@
+const docsifyInit = require('../helpers/docsify-init');
+
+describe(`Index file hosting`, function() {
+  const sharedOptions = {
+    config: {
+      basePath: `${TEST_HOST}/docs/index.html#/`,
+    },
+    testURL: `${TEST_HOST}/docs/index.html#/`,
+  };
+
+  test('should serve from index file', async () => {
+    await docsifyInit(sharedOptions);
+
+    await expect(page).toHaveText(
+      '#main',
+      'A magical documentation site generator'
+    );
+    expect(page.url()).toMatch(/index\.html#\/$/);
+  });
+
+  test('should use index file links in sidebar from index file hosting', async () => {
+    await docsifyInit(sharedOptions);
+
+    await page.click('a[href="#/quickstart"]');
+    await expect(page).toHaveText('#main', 'Quick start');
+    expect(page.url()).toMatch(/index\.html#\/quickstart$/);
+  });
+});