test: add edge case tests

src/storage/FsTaskRepository.test.ts

@@ -195,4 +195,52 @@ describe("FsTaskRepository", () => {
 		expect(tasks[0].id).not.toBe(first.id);
 		expect(tasks[0].description).toBe("second");
 	});
+
+	it("creates task with Cyrillic title and slug", async () => {
+		const task = await repo.create(folder, {
+			...sampleTask,
+			title: "Тестовая задача",
+		});
+		expect(task.title).toBe("Тестовая задача");
+
+		const files = await fs.readdir(folder);
+		expect(files).toEqual([`тестовая-задача${TASK_FILE_EXTENSION}`]);
+	});
+
+	it("creates task with title exactly at MAX_TASK_TITLE_LENGTH", async () => {
+		const title = "a".repeat(80);
+		const task = await repo.create(folder, { ...sampleTask, title });
+		expect(task.title).toBe(title);
+
+		const files = await fs.readdir(folder);
+		expect(files).toEqual([`${title}${TASK_FILE_EXTENSION}`]);
+
+		const found = await repo.getById(folder, task.id);
+		expect(found?.title).toBe(title);
+	});
+
+	it("creates task with tags containing special characters", async () => {
+		const task = await repo.create(folder, {
+			...sampleTask,
+			tags: ["c#", "c++", "tag name", "tag:value"],
+		});
+
+		const files = await fs.readdir(folder);
+		expect(files).toHaveLength(1);
+
+		const content = await fs.readFile(
+			`${folder}/fix-login-bug${TASK_FILE_EXTENSION}`,
+		);
+		expect(content).toContain("c#");
+		expect(content).toContain("tag:value");
+	});
+
+	it("getFilePath produces consistent slug regardless of special characters", async () => {
+		const task = await repo.create(folder, {
+			...sampleTask,
+			title: "Fix___bug...",
+		});
+		const files = await fs.readdir(folder);
+		expect(files).toEqual([`fix-bug${TASK_FILE_EXTENSION}`]);
+	});
 });