import { describe, it, expect, beforeEach, afterEach } from "@jest/globals";
import { promises as fs } from "fs";
import os from "os";
import path from "path";
import { setFrontmatter } from "../set_frontmatter.js";
import { setActiveTheme } from "../../themes/index.js";
import { setActiveStyle } from "../../styles/index.js";
describe("setFrontmatter", () => {
let tempDir: string;
beforeEach(async () => {
tempDir = await fs.mkdtemp(path.join(os.tmpdir(), "marp-frontmatter-"));
setActiveTheme("default");
setActiveStyle("default");
});
afterEach(async () => {
await fs.rm(tempDir, { recursive: true, force: true });
});
it("creates the required frontmatter when missing", async () => {
const filePath = path.join(tempDir, "slides.md");
await fs.writeFile(filePath, "# Slide 1\n", "utf-8");
await setFrontmatter({ filePath });
const updated = await fs.readFile(filePath, "utf-8");
// Check for required fields without being strict about formatting
expect(updated).toContain("marp: true");
expect(updated).toContain("theme: default");
expect(updated).toMatch(/header:\s*['"']?['"']?/); // header can be empty string with quotes or without
expect(updated).toContain("paginate: false");
expect(updated.trimEnd()).toContain("# Slide 1");
});
it("preserves existing header and paginate when values are omitted", async () => {
const filePath = path.join(tempDir, "existing.md");
const original = [
"---",
"marp: true",
"theme: uncover",
"header: Existing header",
"paginate: true",
"custom: keep-me",
"---",
"",
"# Slide",
].join("\n");
await fs.writeFile(filePath, original, "utf-8");
setActiveTheme("gaia");
await setFrontmatter({ filePath });
const updated = await fs.readFile(filePath, "utf-8");
expect(updated).toContain("theme: gaia");
expect(updated).toContain("header: Existing header");
expect(updated).toContain("paginate: true");
expect(updated).toContain("custom: keep-me");
});
it("overrides header and paginate when provided", async () => {
const filePath = path.join(tempDir, "override.md");
const original = [
"---",
"marp: true",
"theme: default",
"---",
"",
"# Slide",
].join("\n");
await fs.writeFile(filePath, original, "utf-8");
setActiveTheme("academic");
await setFrontmatter({
filePath,
header: "Kickoff: FY25",
paginate: true,
});
const updated = await fs.readFile(filePath, "utf-8");
// Check that the header contains the value (gray-matter may use single or double quotes)
expect(updated).toMatch(/header:\s*['"]Kickoff: FY25['"]/);
expect(updated).toContain("paginate: true");
expect(updated).toContain("theme: academic");
});
it("injects style CSS when rich style is active", async () => {
const filePath = path.join(tempDir, "styled.md");
await fs.writeFile(filePath, "# Slide 1\n", "utf-8");
setActiveStyle("rich");
const result = await setFrontmatter({ filePath });
const updated = await fs.readFile(filePath, "utf-8");
expect(updated).toContain("style:");
// Check response includes style name
const responseText = result.content[0].text;
const response = JSON.parse(responseText);
expect(response.style).toBe("rich");
});
it("does not inject style CSS when default style is active", async () => {
const filePath = path.join(tempDir, "nostyle.md");
await fs.writeFile(filePath, "# Slide 1\n", "utf-8");
setActiveStyle("default");
const result = await setFrontmatter({ filePath });
const updated = await fs.readFile(filePath, "utf-8");
// style field should not be present (no CSS to inject)
expect(updated).not.toMatch(/^style:/m);
// Response should still include style name
const responseText = result.content[0].text;
const response = JSON.parse(responseText);
expect(response.style).toBe("default");
});
});
