feat: Support GitHub Flavored Markdown (#24)

fixtures/code/README.md

@@ -29,3 +29,13 @@ It is also possible to inject markdown:
 ```
 
 <!--- @@inject: https://github.com/streetsidesoftware/inject-markdown/blob/d7de2f5fe/src/app.mts#L15-L19 --->
+
+## GitHub Footnote
+
+|        | version | Node | Support               | End-Of-Life |
+| :----- | :------ | :--- | :-------------------- | :---------- |
+| cspell | 6.x     | 14.x | In Active Development | TBD         |
+| cspell | 5.x     | 12.x | Paid support only[^1] | 2022-10-01  |
+| cspell | 4.x     | 10.x | Paid support only[^1] | 2022-05-01  |
+
+[^1]: [Support - Street Side Software](https://streetsidesoftware.com/support/#maintenance-agreements)

package.json

@@ -65,6 +65,7 @@
     "globby": "^13.1.3",
     "node-fetch": "^3.3.0",
     "remark": "^14.0.2",
+    "remark-gfm": "^3.0.1",
     "remark-mdx": "^2.2.1",
     "remark-parse": "^10.0.1",
     "remark-stringify": "^10.0.2",

src/FileInjector/FileInjector.ts

@@ -3,9 +3,10 @@ import * as path from 'node:path';
 import assert from 'assert';
 import chalk, { supportsColor } from 'chalk';
 import type { Code, Content, Heading, HTML, Parent, Root } from 'mdast';
+import remarkGfm from 'remark-gfm';
 import remarkParse from 'remark-parse';
 import remarkStringify from 'remark-stringify';
-import { unified } from 'unified';
+import { type Processor, unified } from 'unified';
 import { is } from 'unist-util-is';
 import { remove } from 'unist-util-remove';
 import { visit } from 'unist-util-visit';
@@ -262,8 +263,7 @@ async function processFileInjections(
             file.data.hasInjections = false;
             return file;
         }
-        const result = await unified()
-            .use(remarkParse)
+        const result = await initParser()
             .use(processHasInjections)
             .use(processInjections)
             .use(remarkStringify, outputOptions)
@@ -403,7 +403,7 @@ async function processFileInjections(
     }
 
     function parseMarkdownFile(file: VFileEx): Root {
-        return unified().use(remarkParse).parse(file);
+        return initParser().parse(file);
     }
 
     function relativePathNormalized(path: URL, relDir?: URL): string {
@@ -675,7 +675,7 @@ function toError(e: unknown): Error {
 
 function errorToComment(err: Error): Root {
     const msg = (err.message || err.toString()).split('\n').join('\n  ');
-    return unified().use(remarkParse).parse(`\
+    return initParser().parse(`\
 <!---
   ${msg}
 --->`);
@@ -699,3 +699,7 @@ function extractLines(content: string, lines: [number, number] | undefined): str
 function refersToTheSameFile(a: RelURL | URL, b: RelURL | URL): boolean {
     return a.pathname === b.pathname && a.search === b.search;
 }
+
+function initParser(): Processor<Root, Root, Root, void> {
+    return unified().use(remarkParse).use(remarkGfm);
+}

src/FileInjector/VFileEx.test.ts

@@ -0,0 +1,9 @@
+import { describe, expect, test } from 'vitest';
+
+import * as VFileEx from './VFileEx.js';
+
+describe('VFileEx', () => {
+    test('VFileEx', () => {
+        expect(VFileEx).toBeDefined();
+    });
+});

src/FileInjector/VFileEx.ts

@@ -1,6 +1,6 @@
 import { Data as VFileData, VFile } from 'vfile';
 
-import { BufferEncoding } from '../FileSystemAdapter/FileSystemAdapter.js';
+import type { BufferEncoding } from '../FileSystemAdapter/FileSystemAdapter.js';
 
 export interface FileData extends VFileData {
     encoding: BufferEncoding;

src/FileInjector/__snapshots__/FileInjector.test.ts.snap

@@ -111,6 +111,16 @@ async function version(): Promise<string> {
 \`\`\`
 
 <!--- @@inject-end: https://github.com/streetsidesoftware/inject-markdown/blob/d7de2f5fe/src/app.mts#L15-L19 --->
+
+## GitHub Footnote
+
+|        | version | Node | Support               | End-Of-Life |
+| :----- | :------ | :--- | :-------------------- | :---------- |
+| cspell | 6.x     | 14.x | In Active Development | TBD         |
+| cspell | 5.x     | 12.x | Paid support only[^1] | 2022-10-01  |
+| cspell | 4.x     | 10.x | Paid support only[^1] | 2022-05-01  |
+
+[^1]: [Support - Street Side Software](https://streetsidesoftware.com/support/#maintenance-agreements)
 ",
     "utf8",
   ],