clanker-agent/packages/coding-agent/test/frontmatter.test.ts

import { describe, expect, it } from "vitest";
import {
  parseFrontmatter,
  stripFrontmatter,
} from "../src/utils/frontmatter.js";

describe("parseFrontmatter", () => {
  it("parses keys, strips quotes, and returns body", () => {
    const input =
      "---\nname: \"skill-name\"\ndescription: 'A desc'\nfoo-bar: value\n---\n\nBody text";
    const { frontmatter, body } =
      parseFrontmatter<Record<string, string>>(input);
    expect(frontmatter.name).toBe("skill-name");
    expect(frontmatter.description).toBe("A desc");
    expect(frontmatter["foo-bar"]).toBe("value");
    expect(body).toBe("Body text");
  });

  it("normalizes newlines and handles CRLF", () => {
    const input = "---\r\nname: test\r\n---\r\nLine one\r\nLine two";
    const { body } = parseFrontmatter<Record<string, string>>(input);
    expect(body).toBe("Line one\nLine two");
  });

  it("throws on invalid YAML frontmatter", () => {
    const input = "---\nfoo: [bar\n---\nBody";
    expect(() => parseFrontmatter<Record<string, string>>(input)).toThrow(
      /at line 1, column 10/,
    );
  });

  it("parses | multiline yaml syntax", () => {
    const input = "---\ndescription: |\n  Line one\n  Line two\n---\n\nBody";
    const { frontmatter, body } =
      parseFrontmatter<Record<string, string>>(input);
    expect(frontmatter.description).toBe("Line one\nLine two\n");
    expect(body).toBe("Body");
  });

  it("returns original content when frontmatter is missing or unterminated", () => {
    const noFrontmatter = "Just text\nsecond line";
    const missingEnd = "---\nname: test\nBody without terminator";
    const resultNoFrontmatter =
      parseFrontmatter<Record<string, string>>(noFrontmatter);
    const resultMissingEnd =
      parseFrontmatter<Record<string, string>>(missingEnd);
    expect(resultNoFrontmatter.body).toBe("Just text\nsecond line");
    expect(resultMissingEnd.body).toBe(
      "---\nname: test\nBody without terminator"
        .replace(/\r\n/g, "\n")
        .replace(/\r/g, "\n"),
    );
  });

  it("returns empty object for empty or comment-only frontmatter", () => {
    const input = "---\n# just a comment\n---\nBody";
    const { frontmatter } = parseFrontmatter(input);
    expect(frontmatter).toEqual({});
  });
});

describe("stripFrontmatter", () => {
  it("removes frontmatter and trims body", () => {
    const input = "---\nkey: value\n---\n\nBody\n";
    expect(stripFrontmatter(input)).toBe("Body");
  });

  it("returns body when no frontmatter present", () => {
    const input = "\n  No frontmatter body  \n";
    expect(stripFrontmatter(input)).toBe("\n  No frontmatter body  \n");
  });
});