feat: search ignore diacritical marks (#1434)

* feat: search ignore diacritical marks

* Check if normalize is supported

* Update docs

* Fix escape

* remove escapeHtml

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

docs/plugins.md

@@ -62,6 +62,12 @@ By default, the hyperlink on the current page is recognized and the content is s
 <script src="//cdn.jsdelivr.net/npm/docsify/lib/plugins/search.min.js"></script>
 ```
 
+This plugin ignores diacritical marks when performing a full text search (e.g., "cafe" will also match "café"). Legacy browsers like IE11 require the following [String.normalize()](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String/normalize) polyfill to ignore diacritical marks:
+
+```html
+<script src="//polyfill.io/v3/polyfill.min.js?features=String.prototype.normalize"></script>
+```
+
 ## Google Analytics
 
 Install the plugin and configure the track id.

src/plugins/search/search.js

@@ -131,6 +131,13 @@ export function genIndex(path, content = '', router, depth) {
   return index;
 }
 
+export function ignoreDiacriticalMarks(keyword) {
+  if (keyword && keyword.normalize) {
+    return keyword.normalize('NFD').replace(/[\u0300-\u036f]/g, '');
+  }
+  return keyword;
+}
+
 /**
  * @param {String} query Search query
  * @returns {Array} Array of results
@@ -152,6 +159,8 @@ export function search(query) {
     const post = data[i];
     let matchesScore = 0;
     let resultStr = '';
+    let handlePostTitle = '';
+    let handlePostContent = '';
     const postTitle = post.title && post.title.trim();
     const postContent = post.body && post.body.trim();
     const postUrl = post.slug || '';
@@ -160,14 +169,23 @@ export function search(query) {
       keywords.forEach(keyword => {
         // From https://github.com/sindresorhus/escape-string-regexp
         const regEx = new RegExp(
-          keyword.replace(/[|\\{}()[\]^$+*?.]/g, '\\$&'),
+          ignoreDiacriticalMarks(keyword).replace(
+            /[|\\{}()[\]^$+*?.]/g,
+            '\\$&'
+          ),
           'gi'
         );
         let indexTitle = -1;
         let indexContent = -1;
+        handlePostTitle = postTitle
+          ? ignoreDiacriticalMarks(postTitle)
+          : postTitle;
+        handlePostContent = postContent
+          ? ignoreDiacriticalMarks(postContent)
+          : postContent;
 
-        indexTitle = postTitle ? postTitle.search(regEx) : -1;
-        indexContent = postContent ? postContent.search(regEx) : -1;
+        indexTitle = postTitle ? handlePostTitle.search(regEx) : -1;
+        indexContent = postContent ? handlePostContent.search(regEx) : -1;
 
         if (indexTitle >= 0 || indexContent >= 0) {
           matchesScore += indexTitle >= 0 ? 3 : indexContent >= 0 ? 2 : 0;
@@ -187,7 +205,7 @@ export function search(query) {
 
           const matchContent =
             '...' +
-            escapeHtml(postContent)
+            handlePostContent
               .substring(start, end)
               .replace(
                 regEx,
@@ -201,7 +219,7 @@ export function search(query) {
 
       if (matchesScore > 0) {
         const matchingPost = {
-          title: escapeHtml(postTitle),
+          title: handlePostTitle,
           content: postContent ? resultStr : '',
           url: postUrl,
           score: matchesScore,

test/e2e/search.test.js

@@ -105,4 +105,23 @@ describe('Search Plugin Tests', function() {
     await page.fill('input[type=search]', 'test');
     await expect(page).toEqualText('.results-panel h2', 'Test Page');
   });
+
+  test('search ignore diacritical marks', async () => {
+    const docsifyInitConfig = {
+      markdown: {
+        homepage: `
+          # Qué es
+
+          docsify genera su sitio web de documentación sobre la marcha. A diferencia de GitBook, no genera archivos estáticos html. En cambio, carga y analiza de forma inteligente sus archivos de Markdown y los muestra como sitio web. Todo lo que necesita hacer es crear un index.html para comenzar y desplegarlo en GitHub Pages.
+        `,
+      },
+      scriptURLs: ['/lib/plugins/search.min.js'],
+    };
+    await docsifyInit(docsifyInitConfig);
+    await page.fill('input[type=search]', 'documentacion');
+    await expect(page).toEqualText('.results-panel h2', 'Que es');
+    await page.click('.clear-button');
+    await page.fill('input[type=search]', 'estáticos');
+    await expect(page).toEqualText('.results-panel h2', 'Que es');
+  });
 });