feat: deduce prefixUrl, slugify headings

Author: metonym

package.json

@@ -19,6 +19,7 @@
     "html-minifier": "^4.0.0",
     "is-relative-url": "^3.0.0",
     "markdown-it": "^12.0.2",
+    "markdown-it-anchor": "^6.0.1",
     "prettier": "^2.2.1",
     "prettier-plugin-svelte": "^1.4.1",
     "prism-svelte": "^0.4.7",

src/preprocessReadme.js

@@ -1,5 +1,6 @@
 import { walk, parse } from "svelte/compiler";
 import Markdown from "markdown-it";
+import markdownItAnchor from "markdown-it-anchor";
 import prettier from "prettier";
 import Prism from "prismjs";
 import "prismjs/components/prism-bash";
@@ -14,6 +15,8 @@ const aliases = {
 let md;
 
 export function preprocessReadme(opts) {
+  const prefixUrl = opts.prefixUrl || `${opts.homepage}/tree/master/`;
+
   if (!md) {
     md = new Markdown({
       html: true,
@@ -45,6 +48,8 @@ export function preprocessReadme(opts) {
         }
       },
     });
+
+    md.use(markdownItAnchor);
   }
 
   return {
@@ -59,11 +64,11 @@ export function preprocessReadme(opts) {
 
       walk(ast, {
         enter(node, parent) {
-          if (opts.prefixUrl && node.type === "Attribute" && node.name === "href") {
+          if (node.type === "Attribute" && node.name === "href") {
             const value = node.value[0];
 
             if (value && !value.raw.startsWith("#") && isRelativeUrl(value.raw)) {
-              const relative_path = new URL(value.raw, opts.prefixUrl).href;
+              const relative_path = new URL(value.raw, prefixUrl).href;
               result = result.replace(value.raw, relative_path);
               cursor += relative_path.length - value.raw.length;
             }

test/package.json

@@ -19,7 +19,5 @@
     "serve": "^11.3.2",
     "svelte": "^3.29.7"
   },
-  "dependencies": {
-    "github-markdown-css": "^4.0.0"
-  }
+  "homepage": "https://github.com/metonym/svelte-readme"
 }

test/rollup.config.js

@@ -18,7 +18,6 @@ export default () => {
             port: 5000,
           }),
       ],
-      prefixUrl: "https://github.com/metonym/svelte-readme/tree/master/test/",
     });
 
   return ["es", "umd"].map((format) => {

test/yarn.lock

@@ -305,11 +305,6 @@ get-stream@^3.0.0:
   resolved "https://registry.yarnpkg.com/get-stream/-/get-stream-3.0.0.tgz#8e943d1358dc37555054ecbe2edb05aa174ede14"
   integrity sha1-jpQ9E1jcN1VQVOy+LtsFqhdO3hQ=
 
-github-markdown-css@^4.0.0:
-  version "4.0.0"
-  resolved "https://registry.yarnpkg.com/github-markdown-css/-/github-markdown-css-4.0.0.tgz#be9f4caf7a389228d4c368336260ffc909061f35"
-  integrity sha512-mH0bcIKv4XAN0mQVokfTdKo2OD5K8WJE9+lbMdM32/q0Ie5tXgVN/2o+zvToRMxSTUuiTRcLg5hzkFfOyBYreg==
-
 has-flag@^3.0.0:
   version "3.0.0"
   resolved "https://registry.yarnpkg.com/has-flag/-/has-flag-3.0.0.tgz#b5d454dc2199ae225699f3467e5a07f3b955bafd"

yarn.lock

@@ -309,6 +309,11 @@ lower-case@^1.1.1:
   resolved "https://registry.yarnpkg.com/lower-case/-/lower-case-1.1.4.tgz#9a2cabd1b9e8e0ae993a4bf7d5875c39c42e8eac"
   integrity sha1-miyr0bno4K6ZOkv31YdcOcQujqw=
 
+markdown-it-anchor@^6.0.1:
+  version "6.0.1"
+  resolved "https://registry.yarnpkg.com/markdown-it-anchor/-/markdown-it-anchor-6.0.1.tgz#f54b78757d0b61455faf8ced775b39498bd6d6f9"
+  integrity sha512-8qX4r5R6AtXla9HKCouEQ40inw69O5jR4VUXlZySsBLxIXlsJ3Yi9JV6JWPU4ZdA8jWTGDDJjJYNLwQ0W4jCag==
+
 markdown-it@^12.0.2:
   version "12.0.2"
   resolved "https://registry.yarnpkg.com/markdown-it/-/markdown-it-12.0.2.tgz#4401beae8df8aa2221fc6565a7188e60a06ef0ed"