From 0033eaf7621103e025c1f531f23cede8e33d3f82 Mon Sep 17 00:00:00 2001
From: haosenwang1018 <haosenwang1018@users.noreply.github.com>
Date: Mon, 16 Mar 2026 19:47:02 +0000
Subject: [PATCH] test: cover MCP_STRICT_ENV leading-tab
 true-with-surrounding-CRLF semantics

---
 tests/config.test.ts | 22 ++++++++++++++++++++++
 1 file changed, 22 insertions(+)

diff --git a/tests/config.test.ts b/tests/config.test.ts
index a48602c..308e54a 100644
--- a/tests/config.test.ts
+++ b/tests/config.test.ts
@@ -108,6 +108,28 @@ describe('config', () => {
       delete process.env.MCP_STRICT_ENV;
     });
 
+
+    test('treats MCP_STRICT_ENV with surrounding-CRLF leading-tab true as strict mode', async () => {
+      process.env.MCP_STRICT_ENV = '\r\n\ttrue\r\n';
+
+      const configPath = join(tempDir, 'missing_env_leading_tab_true_surrounded_crlf.json');
+      await writeFile(
+        configPath,
+        JSON.stringify({
+          mcpServers: {
+            test: {
+              command: 'echo',
+              env: { TOKEN: '${NONEXISTENT_VAR}' },
+            },
+          },
+        })
+      );
+
+      await expect(loadConfig(configPath)).rejects.toThrow('Missing environment variable');
+
+      delete process.env.MCP_STRICT_ENV;
+    });
+
     test('throws error on missing env vars in strict mode (default)', async () => {
       // Ensure strict mode is enabled (default)
       delete process.env.MCP_STRICT_ENV;