diff --git a/frontend/sync-client/src/file-operations/file-operations.test.ts b/frontend/sync-client/src/file-operations/file-operations.test.ts
index 85364eb2..1fd99aea 100644
--- a/frontend/sync-client/src/file-operations/file-operations.test.ts
+++ b/frontend/sync-client/src/file-operations/file-operations.test.ts
@@ -1,17 +1,26 @@
-import { FileSystemOperations } from "sync-client";
-import type { RelativePath } from "../persistence/database";
+import type { FileSystemOperations } from "sync-client";
+import type { Database, RelativePath } from "../persistence/database";
 import { FileOperations } from "./file-operations";
 import { Logger } from "../tracing/logger";
-import assert from "assert";
+import { assertSetContainsExactly } from "src/utils/assert-set-contains-exactly";
 
 describe("File operations", () => {
+	class MockDatabase {
+		public async updatePath(
+			_oldRelativePath: RelativePath,
+			_newRelativePath: RelativePath
+		): Promise<void> {
+			// this is called but irrelevant for this mock
+		}
+	}
+
 	class FakeFileSystemOperations implements FileSystemOperations {
 		public readonly names = new Set<string>();
 
-		public listAllFiles(): Promise<RelativePath[]> {
+		public async listAllFiles(): Promise<RelativePath[]> {
 			throw new Error("Method not implemented.");
 		}
-		public read(path: RelativePath): Promise<Uint8Array> {
+		public async read(_path: RelativePath): Promise<Uint8Array> {
 			throw new Error("Method not implemented.");
 		}
 		public async write(
@@ -20,23 +29,25 @@ describe("File operations", () => {
 		): Promise<void> {
 			this.names.add(path);
 		}
-		public atomicUpdateText(
-			path: RelativePath,
-			updater: (currentContent: string) => string
+		public async atomicUpdateText(
+			_path: RelativePath,
+			_updater: (currentContent: string) => string
 		): Promise<string> {
 			throw new Error("Method not implemented.");
 		}
-		public getFileSize(path: RelativePath): Promise<number> {
+		public async getFileSize(_path: RelativePath): Promise<number> {
 			throw new Error("Method not implemented.");
 		}
-		public getModificationTime(path: RelativePath): Promise<Date> {
+		public async getModificationTime(_path: RelativePath): Promise<Date> {
 			throw new Error("Method not implemented.");
 		}
 		public async exists(path: RelativePath): Promise<boolean> {
 			return this.names.has(path);
 		}
-		public async createDirectory(path: RelativePath): Promise<void> {}
-		public delete(path: RelativePath): Promise<void> {
+		public async createDirectory(_path: RelativePath): Promise<void> {
+			// this is called but irrelevant for this mock
+		}
+		public async delete(_path: RelativePath): Promise<void> {
 			throw new Error("Method not implemented.");
 		}
 		public async rename(
@@ -49,54 +60,54 @@ describe("File operations", () => {
 	}
 
 	test("should deconflict renames", async () => {
-		let fs = new FakeFileSystemOperations();
-		let fileOperations = new FileOperations(new Logger(), fs);
+		const fs = new FakeFileSystemOperations();
+		const fileOperations = new FileOperations(
+			new Logger(),
+			new MockDatabase() as Database, // eslint-disable-line @typescript-eslint/no-unsafe-type-assertion
+			fs
+		);
 
 		await fileOperations.create("a", new Uint8Array());
-		assertSetOnlyContains(fs.names, "a");
+		assertSetContainsExactly(fs.names, "a");
 		await fileOperations.move("a", "b");
-		assertSetOnlyContains(fs.names, "b");
+		assertSetContainsExactly(fs.names, "b");
 
 		await fileOperations.create("c", new Uint8Array());
-		assertSetOnlyContains(fs.names, "b", "c");
+		assertSetContainsExactly(fs.names, "b", "c");
 
 		await fileOperations.move("c", "b");
-		assertSetOnlyContains(fs.names, "b", "b (1)");
+		assertSetContainsExactly(fs.names, "b", "b (1)");
 
 		await fileOperations.create("c", new Uint8Array());
 		await fileOperations.move("c", "b");
-		assertSetOnlyContains(fs.names, "b", "b (1)", "b (2)");
+		assertSetContainsExactly(fs.names, "b", "b (1)", "b (2)");
 	});
 
 	test("should deconflict renames with file extension", async () => {
-		let fs = new FakeFileSystemOperations();
-		let fileOperations = new FileOperations(new Logger(), fs);
+		const fs = new FakeFileSystemOperations();
+		const fileOperations = new FileOperations(
+			new Logger(),
+			new MockDatabase() as Database, // eslint-disable-line @typescript-eslint/no-unsafe-type-assertion
+			fs
+		);
 
 		await fileOperations.create("b.md", new Uint8Array());
 		await fileOperations.create("c.md", new Uint8Array());
 		await fileOperations.move("c.md", "b.md");
-		assertSetOnlyContains(fs.names, "b.md", "b (1).md");
+		assertSetContainsExactly(fs.names, "b.md", "b (1).md");
 	});
 
 	test("should deconflict renames with paths", async () => {
-		let fs = new FakeFileSystemOperations();
-		let fileOperations = new FileOperations(new Logger(), fs);
+		const fs = new FakeFileSystemOperations();
+		const fileOperations = new FileOperations(
+			new Logger(),
+			new MockDatabase() as Database, // eslint-disable-line @typescript-eslint/no-unsafe-type-assertion
+			fs
+		);
 
 		await fileOperations.create("a/b.c/d", new Uint8Array());
 		await fileOperations.create("a/b.c/e", new Uint8Array());
 		await fileOperations.move("a/b.c/d", "a/b.c/e");
-		assertSetOnlyContains(fs.names, "a/b.c/e", "a/b.c/e (1)");
+		assertSetContainsExactly(fs.names, "a/b.c/e", "a/b.c/e (1)");
 	});
 });
-
-function assertSetOnlyContains<T>(set: Set<T>, ...values: T[]) {
-	assert(
-		set.size === values.length &&
-			Array.from(set).every((value) => values.includes(value)),
-		`Expected set to contain only ${values.map((v) => '"' + v + '"').join(", ")}, but it contained ${Array.from(
-			set
-		)
-			.map((v) => '"' + v + '"')
-			.join(", ")}`
-	);
-}
diff --git a/frontend/sync-client/src/utils/assert-set-contains-exactly.ts b/frontend/sync-client/src/utils/assert-set-contains-exactly.ts
new file mode 100644
index 00000000..9682044e
--- /dev/null
+++ b/frontend/sync-client/src/utils/assert-set-contains-exactly.ts
@@ -0,0 +1,13 @@
+import assert from "assert";
+
+export function assertSetContainsExactly<T>(set: Set<T>, ...values: T[]): void {
+	assert(
+		set.size === values.length &&
+			Array.from(set).every((value) => values.includes(value)),
+		`Expected set to contain only ${values.map((v) => '"' + v + '"').join(", ")}, but it contained ${Array.from(
+			set
+		)
+			.map((v) => '"' + v + '"')
+			.join(", ")}`
+	);
+}