feat(v2): truncate marker as blog option (#1706)

* feat(v2): allowed more as truncate marker

* feat(v2): blog support truncateMarker option

* feat(v2): blog support truncateMarker option

CHANGELOG-2.x.md

@@ -2,6 +2,7 @@
 
 ## Unreleased
 
+- Add `truncateMarker` option to blog plugin, support string or regex.
 - Webpack `optimization.removeAvailableModules` is now disabled for performance gain. See https://github.com/webpack/webpack/releases/tag/v4.38.0 for more context.
 
 ## 2.0.0-alpha.24

packages/docusaurus-plugin-content-blog/src/index.js

@@ -31,6 +31,7 @@ const DEFAULT_OPTIONS = {
   blogTagsPostsComponent: '@theme/BlogTagsPostsPage',
   remarkPlugins: [],
   rehypePlugins: [],
+  truncateMarker: /<!--\s*(truncate)\s*-->/, // string or regex
 };
 
 module.exports = function(context, opts) {
@@ -340,7 +341,7 @@ module.exports = function(context, opts) {
     },
 
     configureWebpack(config, isServer, {getBabelLoader, getCacheLoader}) {
-      const {rehypePlugins, remarkPlugins} = options;
+      const {rehypePlugins, remarkPlugins, truncateMarker} = options;
       return {
         module: {
           rules: [
@@ -359,6 +360,9 @@ module.exports = function(context, opts) {
                 },
                 {
                   loader: path.resolve(__dirname, './markdownLoader.js'),
+                  options: {
+                    truncateMarker,
+                  },
                 },
               ].filter(Boolean),
             },

packages/docusaurus-plugin-content-blog/src/markdownLoader.js

@@ -5,20 +5,25 @@
  * LICENSE file in the root directory of this source tree.
  */
 
-const {parseQuery} = require('loader-utils');
-
-const TRUNCATE_MARKER = /<!--\s*truncate\s*-->/;
+const {parseQuery, getOptions} = require('loader-utils');
 
 module.exports = async function(fileString) {
   const callback = this.async();
 
+  const {truncateMarker} = getOptions(this);
+
   let finalContent = fileString;
 
   // Truncate content if requested (e.g: file.md?truncated=true)
   const {truncated} = this.resourceQuery && parseQuery(this.resourceQuery);
-  if (truncated && TRUNCATE_MARKER.test(fileString)) {
+  if (
+    truncated &&
+    (typeof truncateMarker === 'string'
+      ? fileString.includes(truncateMarker)
+      : truncateMarker.test(fileString))
+  ) {
     // eslint-disable-next-line
-    finalContent = fileString.split(TRUNCATE_MARKER)[0];
+    finalContent = fileString.split(truncateMarker)[0];
   }
   return callback(null, finalContent);
 };