test: update tests, add eslint rules

src/utils/markdown.test.ts

@@ -1,6 +1,8 @@
-import { describe, it, expect } from "vitest";
-import { parseTaskFile, serializeTask } from "./markdown";
 import { Task } from "@/model/task";
+import { describe, expect, it } from "vitest";
+import { parseTaskFile, serializeTask } from "./markdown";
+
+const ISO_RE = /^\d{4}-\d{2}-\d{2}T\d{2}:\d{2}:\d{2}.\d{3}Z$/;
 
 const fullTask: Task = {
 	id: "550e8400-e29b-41d4-a716-446655440000",
@@ -51,20 +53,17 @@ describe("markdown", () => {
 		expect(task.priority).toBe("medium");
 		expect(task.tags).toEqual([]);
 		expect(task.assignee).toBe("");
-		expect(task.created).toBeTruthy();
-		expect(task.updated).toBeTruthy();
-	});
-
-	it("serializeTask produces valid frontmatter", () => {
-		const result = serializeTask(fullTask);
-		expect(result).toContain("---");
-		expect(result).toContain("title: Пофиксить баг логина");
-		expect(result).toContain("status: in-progress");
-		expect(result).toContain("Ошибка валидации токена");
+		expect(task.created).toMatch(ISO_RE);
+		expect(task.updated).toMatch(ISO_RE);
 	});
 
 	it("round-trip: serialize → parse produces the same task", () => {
 		const serialized = serializeTask(fullTask);
+		expect(serialized).toContain("---");
+		expect(serialized).toContain("title: Пофиксить баг логина");
+		expect(serialized).toContain("status: in-progress");
+		expect(serialized).toContain("Ошибка валидации токена");
+
 		const parsed = parseTaskFile(serialized);
 		expect(parsed).toEqual(fullTask);
 	});
@@ -78,4 +77,23 @@ describe("markdown", () => {
 		const parsed = parseTaskFile(serialized);
 		expect(parsed.description).toBe(task.description);
 	});
+
+	it("converts Date values from YAML to ISO strings", () => {
+		const created = new Date("2026-07-12T10:00:00.000Z");
+		const updated = new Date("2026-07-12T11:00:00.000Z");
+		const content = [
+			"---",
+			'id: "date-task"',
+			'title: "With dates"',
+			`created: ${created.toISOString()}`,
+			`updated: ${updated.toISOString()}`,
+			"---",
+			"",
+		].join("\n");
+
+		// front-matter/js-yaml may return Date for unquoted ISO-like timestamps
+		const task = parseTaskFile(content);
+		expect(task.created).toBe("2026-07-12T10:00:00.000Z");
+		expect(task.updated).toBe("2026-07-12T11:00:00.000Z");
+	});
 });