From 64d97ccf30aa1483efa74ead4b11ae60bd924bc8 Mon Sep 17 00:00:00 2001
From: olaservo <olahungerford@gmail.com>
Date: Thu, 19 Feb 2026 05:53:09 -0700
Subject: [PATCH] fix(filesystem): fix quote style and add fileURLToPath
 regression test

Follow-up to #3205. Fixes import quote style inconsistency (double to
single quotes) and adds a regression test using pathToFileURL() to
verify properly-encoded file:// URIs are handled correctly on all
platforms.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
---
 src/filesystem/__tests__/roots-utils.test.ts | 16 ++++++++++++++++
 src/filesystem/roots-utils.ts                |  2 +-
 2 files changed, 17 insertions(+), 1 deletion(-)

diff --git a/src/filesystem/__tests__/roots-utils.test.ts b/src/filesystem/__tests__/roots-utils.test.ts
index 1a39483953..d279a5ae60 100644
--- a/src/filesystem/__tests__/roots-utils.test.ts
+++ b/src/filesystem/__tests__/roots-utils.test.ts
@@ -3,6 +3,7 @@ import { getValidRootDirectories } from '../roots-utils.js';
 import { mkdtempSync, rmSync, mkdirSync, writeFileSync, realpathSync } from 'fs';
 import { tmpdir } from 'os';
 import { join } from 'path';
+import { pathToFileURL } from 'url';
 import type { Root } from '@modelcontextprotocol/sdk/types.js';
 
 describe('getValidRootDirectories', () => {
@@ -45,6 +46,21 @@ describe('getValidRootDirectories', () => {
       expect(result).toHaveLength(3);
     });
 
+    it('should handle standard file URIs from pathToFileURL', async () => {
+      // pathToFileURL produces properly-encoded URIs (e.g. file:///C:/... on Windows)
+      // This is the format VS Code and other editors send via MCP roots
+      const roots: Root[] = [
+        { uri: pathToFileURL(testDir1).href, name: 'Standard File URI' },
+        { uri: pathToFileURL(testDir2).href, name: 'Standard File URI 2' },
+      ];
+
+      const result = await getValidRootDirectories(roots);
+
+      expect(result).toContain(testDir1);
+      expect(result).toContain(testDir2);
+      expect(result).toHaveLength(2);
+    });
+
     it('should normalize complex paths', async () => {
       const subDir = join(testDir1, 'subdir');
       mkdirSync(subDir);
diff --git a/src/filesystem/roots-utils.ts b/src/filesystem/roots-utils.ts
index 5e26bb246b..2a97cbdb0e 100644
--- a/src/filesystem/roots-utils.ts
+++ b/src/filesystem/roots-utils.ts
@@ -3,7 +3,7 @@ import path from 'path';
 import os from 'os';
 import { normalizePath } from './path-utils.js';
 import type { Root } from '@modelcontextprotocol/sdk/types.js';
-import { fileURLToPath } from "url";
+import { fileURLToPath } from 'url';
 
 /**
  * Converts a root URI to a normalized directory path with basic security validation.