fix(daemon): handle macOS socket path length limit

.changeset/macos-socket-path-length-limit.md

@@ -0,0 +1,5 @@
+---
+"@nanocollective/nanocoder": patch
+---
+
+Handle macOS socket path length limit

source/daemon/lockfile.spec.ts

@@ -135,6 +135,23 @@ test('getSocketPath returns a project-local .sock file on non-Windows', t => {
 	t.is(sock, join(root, '.nanocoder', 'daemon.sock'));
 });
 
+test('getSocketPath on macOS uses project dir for short paths and temp dir for long paths', t => {
+	if (process.platform !== 'darwin') {
+		t.pass('skipped: macOS-only assertion');
+		return;
+	}
+	// Short path should use project-local socket
+	const shortRoot = '/tmp/short';
+	const shortSock = getSocketPath(shortRoot);
+	t.is(shortSock, join(shortRoot, '.nanocoder', 'daemon.sock'));
+	// Long path (>104 bytes) should use temp directory with hash
+	const longRoot = '/tmp/' + 'a'.repeat(200);
+	const longSock = getSocketPath(longRoot);
+	t.true(longSock.startsWith(tmpdir()));
+	t.regex(longSock, /nanocoder-daemon-[a-f0-9]{10}\.sock$/);
+	t.not(longSock, join(longRoot, '.nanocoder', 'daemon.sock'));
+});
+
 test('getSocketPath returns a named pipe path on Windows', t => {
 	if (process.platform !== 'win32') {
 		t.pass('skipped: Windows-only assertion');
@@ -146,4 +163,4 @@ test('getSocketPath returns a named pipe path on Windows', t => {
 	t.regex(a, /^\\\\\.\\pipe\\nanocoder-daemon-[a-f0-9]{10}$/);
 	t.regex(b, /^\\\\\.\\pipe\\nanocoder-daemon-[a-f0-9]{10}$/);
 	t.not(a, b, 'distinct project roots produce distinct pipes');
-});
+});

source/daemon/lockfile.ts

@@ -15,6 +15,7 @@
 import {createHash, randomBytes} from 'node:crypto';
 import {existsSync, mkdirSync} from 'node:fs';
 import {readFile, rename, unlink, writeFile} from 'node:fs/promises';
+import {tmpdir} from 'node:os';
 import {dirname, join} from 'node:path';
 
 export interface DaemonLock {
@@ -45,6 +46,22 @@ export function getSocketPath(projectRoot: string): string {
 			.slice(0, 10);
 		return `\\\\.\\pipe\\nanocoder-daemon-${hash}`;
 	}
+
+	// On macOS, the socket path must be shorter than 104 bytes.
+	const DARWIN_SOCKET_PATH_CAPACITY = 104;
+	if (
+		process.platform === 'darwin' &&
+		Buffer.byteLength(projectRoot) > DARWIN_SOCKET_PATH_CAPACITY
+	) {
+		// Use a hash of the project root to keep and create a unique socket path in macOS temporary directory.
+		//
+		const hash = createHash('sha256')
+			.update(projectRoot)
+			.digest('hex')
+			.slice(0, 10)
+			.toLowerCase();
+		return join(tmpdir(), `nanocoder-daemon-${hash}.sock`);
+	}
 	return join(projectRoot, '.nanocoder', 'daemon.sock');
 }