feat(course-format): markdown extraction, discovery, loading, repository

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

packages/course-format/test/markdown.test.ts

@@ -0,0 +1,89 @@
+import { describe, expect, test } from "bun:test";
+import { extractHints, extractSection, slugify } from "../src/markdown";
+
+describe("slugify", () => {
+  test("follows GitHub's algorithm", () => {
+    expect(slugify("Exercise 3.1 — `move`")).toBe("exercise-31--move");
+    expect(slugify("Why this module")).toBe("why-this-module");
+    expect(slugify("Rules as functions `State → State`")).toBe("rules-as-functions-state--state");
+    expect(slugify("**Bold** and [a link](http://x.y)")).toBe("bold-and-a-link");
+  });
+});
+
+const sample = `# Top
+
+intro
+
+## First
+
+one
+
+### Middle
+
+middle body
+
+\`\`\`sh
+# not a heading
+\`\`\`
+
+#### Deeper
+
+deep body
+
+### Sibling
+
+sibling body
+
+## Last
+
+end
+`;
+
+describe("extractSection", () => {
+  test("returns only the middle section, including deeper headings", () => {
+    const s = extractSection(sample, "middle");
+    expect(s).not.toBeNull();
+    expect(s!.startsWith("### Middle")).toBe(true);
+    expect(s).toContain("# not a heading");
+    expect(s).toContain("deep body");
+    expect(s).not.toContain("sibling body");
+    expect(s).not.toContain("one");
+  });
+  test("returns null for an unknown anchor", () => {
+    expect(extractSection(sample, "nope")).toBeNull();
+  });
+  test("a section runs to the end of file when nothing follows", () => {
+    expect(extractSection(sample, "last")).toBe("## Last\n\nend");
+  });
+});
+
+describe("extractHints", () => {
+  const md = `## Hints
+
+<details><summary>Exercise 3.1 (move) — nudge</summary>
+
+Think about direction.
+
+</details>
+
+<details><summary>Exercise 3.1 (move) — stronger hint</summary>
+
+Add the delta.
+
+</details>
+
+<details><summary>Exercise 3.2 (inBounds) — nudge</summary>
+
+Other.
+
+</details>
+`;
+  test("returns matching blocks in order with trimmed labels", () => {
+    const h = extractHints(md, "Exercise 3.1 (move)");
+    expect(h.map((x) => x.label)).toEqual(["nudge", "stronger hint"]);
+    expect(h[0]!.body).toBe("Think about direction.");
+  });
+  test("returns [] when nothing matches", () => {
+    expect(extractHints(md, "Exercise 9.9")).toEqual([]);
+  });
+});