add implicit link plugin

src/transform/plugins/implicit-link/implicit-link.ts

@@ -0,0 +1,51 @@
+import StateCore from 'markdown-it/lib/rules_core/state_core';
+
+export function replaceTokens(state: StateCore) {
+    const {tokens} = state;
+    for (let i = 0; i < tokens.length; i++) {
+        if (tokens[i].type !== 'inline' || !tokens[i].children) continue;
+
+        const splicePointsMap: Map<number, number> = new Map();
+
+        tokens[i].children?.forEach((children, childrenIndex) => {
+            if (children.type === 'text' && isUrl(children.content)) {
+                splicePointsMap.set(i, childrenIndex);
+            }
+        });
+
+        splicePointsMap.forEach((childrenIndex, tokenIndex) => {
+            const token = tokens[tokenIndex];
+
+            //TODO: refactor. children never nullable
+            if (!token.children) return;
+
+            const children = token.children[childrenIndex];
+
+            tokens.splice(tokenIndex - 1, 3, token);
+            token.children.splice(childrenIndex, 1, ...createLinkToken(state, children.content));
+        });
+    }
+}
+
+function isUrl(maybeUrl: string) {
+    try {
+        // eslint-disable-next-line no-new
+        new URL(maybeUrl);
+    } catch (err) {
+        return false;
+    }
+
+    return true;
+}
+
+function createLinkToken(state: StateCore, link: string) {
+    const linkOpenToken = new state.Token('link_open', 'a', 1);
+    linkOpenToken.attrSet('href', link);
+
+    const textToken = new state.Token('text', '', 0);
+    textToken.content = link;
+
+    const linkClose = new state.Token('link_close', 'a', -1);
+
+    return [linkOpenToken, textToken, linkClose];
+}

src/transform/plugins/implicit-link/index.ts

@@ -0,0 +1,10 @@
+import MarkdownIt from 'markdown-it';
+import {replaceTokens} from './implicit-link';
+
+const implicitLink = (md: MarkdownIt) => {
+    md.core.ruler.after('links', 'implicit-link', replaceTokens);
+
+    return md;
+};
+
+export default implicitLink;

test/__snapshots__/implicit-link.test.ts.snap

@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`implicit-link renders implicit-link 1`] = `"<a href=\\"https://google.com\\">https://google.com</a>"`;

test/implicit-link.test.ts

@@ -0,0 +1,14 @@
+import initMarkdown from '../src/transform/md';
+import plugin from '../src/transform/plugins/block-anchor';
+import implicitLink from '../src/transform/plugins/implicit-link';
+import links from '../src/transform/plugins/links';
+
+const {parse, compile} = initMarkdown({plugins: [plugin, links, implicitLink]});
+
+describe('implicit-link', function () {
+    it('renders implicit-link', () => {
+        const input = 'https://google.com';
+        const actual = compile(parse(input));
+        expect(actual).toMatchSnapshot();
+    });
+});

tsconfig.json

@@ -7,7 +7,8 @@
     "baseUrl": ".",
     "declaration": true,
     "target": "ES6",
-    "types": ["node", "jest"]
+    "types": ["node", "jest"],
+    "esModuleInterop": true
   },
   "include": ["src/**/*", "test/**/*"]
 }