From 3dfafe9ce637b17dad730f8b7428f661bf30d13b Mon Sep 17 00:00:00 2001
From: Andras Schmelczer <andras@schmelczer.dev>
Date: Sat, 22 Nov 2025 20:49:53 +0000
Subject: [PATCH] Fix file operations

---
 .../file-operations/file-operations.test.ts   | 57 +++++++++++++++++++
 .../src/file-operations/file-operations.ts    | 10 +++-
 2 files changed, 64 insertions(+), 3 deletions(-)

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 675fdce1..3b1f6710 100644
--- a/frontend/sync-client/src/file-operations/file-operations.test.ts
+++ b/frontend/sync-client/src/file-operations/file-operations.test.ts
@@ -159,4 +159,61 @@ describe("File operations", () => {
 			"a/b.c/e (1)"
 		);
 	});
+
+	it("should continue deconfliction from existing number in filename", async () => {
+		const fileSystemOperations = new FakeFileSystemOperations();
+		const fileOperations = new FileOperations(
+			new Logger(),
+			new MockDatabase() as Database, // eslint-disable-line @typescript-eslint/no-unsafe-type-assertion
+			fileSystemOperations
+		);
+
+		await fileOperations.create("document (5).md", new Uint8Array());
+		await fileOperations.create("other.md", new Uint8Array());
+
+		await fileOperations.move("other.md", "document (5).md");
+		assertSetContainsExactly(
+			fileSystemOperations.names,
+			"document (5).md",
+			"document (6).md"
+		);
+
+		await fileOperations.create("another.md", new Uint8Array());
+		await fileOperations.move("another.md", "document (5).md");
+		assertSetContainsExactly(
+			fileSystemOperations.names,
+			"document (5).md",
+			"document (6).md",
+			"document (7).md"
+		);
+	});
+
+	it("should handle dotfiles correctly", async () => {
+		const fileSystemOperations = new FakeFileSystemOperations();
+		const fileOperations = new FileOperations(
+			new Logger(),
+			new MockDatabase() as Database, // eslint-disable-line @typescript-eslint/no-unsafe-type-assertion
+			fileSystemOperations
+		);
+
+		await fileOperations.create(".gitignore", new Uint8Array());
+		await fileOperations.create("temp", new Uint8Array());
+		await fileOperations.move("temp", ".gitignore");
+		assertSetContainsExactly(
+			fileSystemOperations.names,
+			".gitignore",
+			".gitignore (1)"
+		);
+
+		await fileOperations.create(".config.json", new Uint8Array());
+		await fileOperations.create("temp2", new Uint8Array());
+		await fileOperations.move("temp2", ".config.json");
+		assertSetContainsExactly(
+			fileSystemOperations.names,
+			".gitignore",
+			".gitignore (1)",
+			".config.json",
+			".config (1).json"
+		);
+	});
 });
diff --git a/frontend/sync-client/src/file-operations/file-operations.ts b/frontend/sync-client/src/file-operations/file-operations.ts
index 038dbbe5..7402a6d6 100644
--- a/frontend/sync-client/src/file-operations/file-operations.ts
+++ b/frontend/sync-client/src/file-operations/file-operations.ts
@@ -25,7 +25,7 @@ export class FileOperations {
 	): [RelativePath, RelativePath] {
 		const pathParts = path.split("/");
 		const fileName = pathParts.pop();
-		if (fileName == "" || fileName == null) {
+		if (!fileName || fileName === "") {
 			throw new Error(`Path '${path}' cannot be empty`);
 		}
 
@@ -234,11 +234,15 @@ export class FileOperations {
 		}
 
 		const nameParts = fileName.split(".");
+		// Handle dotfiles: ".gitignore" should have no extension, ".config.json" should have ".json"
+		const isDotfile = fileName.startsWith(".") && nameParts[0] === "";
 		const extension =
-			nameParts.length > 1 ? "." + nameParts[nameParts.length - 1] : "";
+			nameParts.length > 1 && !(isDotfile && nameParts.length === 2)
+				? "." + nameParts[nameParts.length - 1]
+				: "";
 		let stem = extension ? nameParts.slice(0, -1).join(".") : fileName;
 		let currentCount = Number.parseInt(
-			FileOperations.PARENTHESES_REGEX.exec(stem)?.groups?.[0] ?? "0"
+			FileOperations.PARENTHESES_REGEX.exec(stem)?.[1] ?? "0"
 		);
 		stem = stem.replace(FileOperations.PARENTHESES_REGEX, "");