fix: block group folder path escapes

src/group-folder.test.ts

@@ -0,0 +1,39 @@
+import path from 'path';
+
+import { describe, expect, it } from 'vitest';
+
+import { isValidGroupFolder, resolveGroupFolderPath, resolveGroupIpcPath } from './group-folder.js';
+
+describe('group folder validation', () => {
+  it('accepts normal group folder names', () => {
+    expect(isValidGroupFolder('main')).toBe(true);
+    expect(isValidGroupFolder('family-chat')).toBe(true);
+    expect(isValidGroupFolder('Team_42')).toBe(true);
+  });
+
+  it('rejects traversal and reserved names', () => {
+    expect(isValidGroupFolder('../../etc')).toBe(false);
+    expect(isValidGroupFolder('/tmp')).toBe(false);
+    expect(isValidGroupFolder('global')).toBe(false);
+    expect(isValidGroupFolder('')).toBe(false);
+  });
+
+  it('resolves safe paths under groups directory', () => {
+    const resolved = resolveGroupFolderPath('family-chat');
+    expect(
+      resolved.endsWith(`${path.sep}groups${path.sep}family-chat`),
+    ).toBe(true);
+  });
+
+  it('resolves safe paths under data ipc directory', () => {
+    const resolved = resolveGroupIpcPath('family-chat');
+    expect(
+      resolved.endsWith(`${path.sep}data${path.sep}ipc${path.sep}family-chat`),
+    ).toBe(true);
+  });
+
+  it('throws for unsafe folder names', () => {
+    expect(() => resolveGroupFolderPath('../../etc')).toThrow();
+    expect(() => resolveGroupIpcPath('/tmp')).toThrow();
+  });
+});