[BUG] Chinese output garbled in Terminal Shell Integration - breaks LLM context understanding on Windows

[LuBao111]

Problem (one or two sentences)

When executing any Python script that produces Chinese output (not limited to simple print statements), the text appears as garbled text (mojibake) in the Roo Code "Executing" interface. While I demonstrated this with a simple print example, this affects all standard output containing Chinese. (It is currently unconfirmed if other programming languages face the same encoding issue on Windows, but it is persistent with Python).

Context (who is affected and when)

This affects Windows users relying on Roo Code's Terminal Shell Integration.
Crucially, this issue impacts not only human readability but also the LLM's ability to interpret the output. Since the model "reads" the output captured via the shell integration to verify execution results, the garbled text prevents the LLM from confirming that the script ran correctly, leading to potential hallucinations or unnecessary debugging loops.

Reproduction steps

1. Create a Python script (e.g., 1.py) with the following content:

   print("Hello, World!")
   print("你好，世界！")

2. Ask Roo Code to run this file: python 1.py
3. Observe Failure: The English text is correct, but the Chinese text is garbled.

4. Verify Fix: Modify the script to force UTF-8 encoding:

   import sys
   sys.stdout.reconfigure(encoding='utf-8')
   print("你好，世界！")

5. Run the script again via Roo Code.
6. Observe Success: The Chinese text now displays correctly, confirming the root cause is stdout encoding.

Expected result

Hello, World!你好，世界！

Actual result

Hello, World! ��ã����磡

Variations tried (optional)

No response

App Version

Version: 3.39.2

API Provider (optional)

DeepSeek

Model Used (optional)

N/A

Roo Code Task Links (optional)

No response

Relevant logs or errors (optional)

Hello, World!
��ã����磡

[roomote]

I've analyzed this issue and here's my proposed implementation plan:

Root Cause:
The VSCode Terminal Shell Integration creates terminals without UTF-8 encoding environment variables. Specifically:

• ExecaTerminalProcess.ts (used when shell integration is disabled) already sets LANG and LC_ALL to en_US.UTF-8
• Terminal.ts getEnv() method (used when shell integration is enabled) does NOT set these variables

This causes encoding issues on Windows where the default console code page is often not UTF-8.

Proposed Fix:

1. Modify src/integrations/terminal/Terminal.ts getEnv() method to add UTF-8 encoding environment variables:
   • LANG: "en_US.UTF-8" - Standard locale setting for UTF-8
   • LC_ALL: "en_US.UTF-8" - Overrides all locale settings to UTF-8
   • PYTHONUTF8: "1" - Enables Python 3.7+ UTF-8 mode (important for Windows)
   • PYTHONIOENCODING: "utf-8" - Sets Python I/O encoding

This approach mirrors what is already done in ExecaTerminalProcess.ts and ensures consistent UTF-8 encoding across both terminal modes.

Why this works:

• The environment variables are passed when creating the VSCode terminal via vscode.window.createTerminal({ env })
• These variables will be inherited by any processes spawned in that terminal
• Python specifically respects PYTHONUTF8 and PYTHONIOENCODING for output encoding
• LANG and LC_ALL help other applications understand the expected encoding

Please mention @roomote in a comment saying that you approve this plan, and I'll proceed with the implementation.

[LuBao111]

ok