Support for remark-lint-strikethrough-marker (#68)

To warn when the number of strikethrough markers is inconsistent and
does not use two strikethrough markers (`~~`) the
`remark-lint-strikethrough-marker` [1] has been added to support such
checks.

[1]: https://github.com/remarkjs/remark-lint/tree/main/packages/remark-lint-strikethrough-marker

GH-67

packages/@svengreb/remark-preset-lint/rules/support.js

@@ -6,6 +6,7 @@
 import footnotes from "remark-footnotes";
 import frontmatter from "remark-frontmatter";
 import gfm from "remark-gfm";
+import strikethroughMarker from "remark-lint-strikethrough-marker";
 
 /**
  * Support for plugins of specification addons and variants.
@@ -50,6 +51,12 @@ const support = {
         tablePipeAlign: true,
       },
     ],
+    /**
+     * Warn when the number of strikethrough markers is inconsistent and does not use two strikethrough markers.
+     * @see https://github.com/remarkjs/remark-lint/tree/main/packages/remark-lint-strikethrough-marker
+     * @see https://github.com/svengreb/styleguide-markdown/blob/main/rules/emphasis.md#strikethrough
+     */
+    [strikethroughMarker, "~~"],
   ],
 };
 

rules/emphasis.md

@@ -64,7 +64,7 @@ Use two (2) asterisk `*` marker to generate spans for bold formatted text.
 
 Use two (2) tilde `~` marker to generate spans for strikethrough text.
 
-> remark-lint: [emphasis-marker][2]
+> remark-lint: [strikethrough-marker][6], [emphasis-marker][2]
 
 ###### Examples
 
@@ -171,3 +171,4 @@ __ Snow            __
 [3]: https://github.com/remarkjs/remark-lint/tree/main/packages/remark-lint-no-emphasis-as-heading
 [4]: https://github.com/remarkjs/remark-lint/tree/main/packages/remark-lint-no-inline-padding
 [5]: https://github.com/remarkjs/remark-lint/tree/main/packages/remark-lint-strong-marker
+[6]: https://github.com/remarkjs/remark-lint/tree/main/packages/remark-lint-strikethrough-marker