fix: telegram html formatting (#435, thanks @RandyVentures)

src/telegram/format.test.ts

@@ -0,0 +1,50 @@
+import { describe, expect, it } from "vitest";
+
+import { markdownToTelegramHtml } from "./format.js";
+
+describe("markdownToTelegramHtml", () => {
+  it("renders basic inline formatting", () => {
+    const res = markdownToTelegramHtml("hi _there_ **boss** `code`");
+    expect(res).toBe("hi <i>there</i> <b>boss</b> <code>code</code>");
+  });
+
+  it("renders links as Telegram-safe HTML", () => {
+    const res = markdownToTelegramHtml("see [docs](https://example.com)");
+    expect(res).toBe('see <a href="https://example.com">docs</a>');
+  });
+
+  it("escapes raw HTML", () => {
+    const res = markdownToTelegramHtml("<b>nope</b>");
+    expect(res).toBe("&lt;b&gt;nope&lt;/b&gt;");
+  });
+
+  it("escapes unsafe characters", () => {
+    const res = markdownToTelegramHtml("a & b < c");
+    expect(res).toBe("a &amp; b &lt; c");
+  });
+
+  it("renders paragraphs with blank lines", () => {
+    const res = markdownToTelegramHtml("first\n\nsecond");
+    expect(res).toBe("first\n\nsecond");
+  });
+
+  it("renders lists without block HTML", () => {
+    const res = markdownToTelegramHtml("- one\n- two");
+    expect(res).toBe("• one\n• two");
+  });
+
+  it("renders ordered lists with numbering", () => {
+    const res = markdownToTelegramHtml("2. two\n3. three");
+    expect(res).toBe("2. two\n3. three");
+  });
+
+  it("flattens headings and blockquotes", () => {
+    const res = markdownToTelegramHtml("# Title\n\n> Quote");
+    expect(res).toBe("Title\n\nQuote");
+  });
+
+  it("renders fenced code blocks", () => {
+    const res = markdownToTelegramHtml("```js\nconst x = 1;\n```");
+    expect(res).toBe("<pre><code>const x = 1;\n</code></pre>");
+  });
+});