Web simulator shows incorrect echo command for s01 demo

[lei-zhenyu]

Bug Description

In the s01 web simulator, the demo uses the following command to create hello.py:

echo 'print("Hello, World!")' > hello.py

This actually writes 'print("Hello, World!")' into the file (with single quotes),
not print("Hello, World!"). As a result, running python hello.py would produce
no output because the file contains a string literal, not valid Python code.

Expected

The file hello.py should contain:

print("Hello, World!")

Actual

The file hello.py actually contains:

'print("Hello, World!")'

Suggested Fix

Use either of these commands instead:

echo print("Hello, World!") > hello.py

or

printf 'print("Hello, World!")\n' > hello.py

Environment

• Discovered via real agent execution on Windows (Git Bash)
• Also reproducible on Linux/Mac with standard bash

[CrazyBoyM]

Thanks for the report. However, in standard bash/zsh, the command:

```sh
echo 'print("Hello, World!")' > hello.py
```

writes `print("Hello, World!")` to the file -- the single quotes are shell syntax (preventing interpretation of the double quotes), not part of the output. You can verify:

```sh
$ echo 'print("Hello, World!")' > hello.py
$ cat hello.py
print("Hello, World!")
```

This might behave differently on Windows `cmd.exe` (which doesn't strip single quotes), but the web simulator and the agent code target bash.

Could you share the exact environment where you reproduced this? If it's specifically a Windows/Git Bash issue, we can note it in the docs.

---

感谢报告。在标准 bash/zsh 中，单引号是 shell 语法不会写入文件。可能在 Windows cmd.exe 下行为不同。能否提供具体的复现环境？

[lei-zhenyu]

I found the exact root cause. When running the agent on Windows, subprocess.run(command, shell=True) calls cmd.exe instead of bash, even inside Git Bash terminal. So the same command behaves differently: - Typed manually in Git Bash → correct (single quotes stripped) - Executed by the agent via subprocess → routed to cmd.exe → single quotes written into file This can be verified: after running the agent, cat hello.py shows 'print("Hello, World!")' with quotes. But typing the same echo command manually in Git Bash gives print("Hello, World!") without quotes. Suggested fix: explicitly set the executable path in subprocess.run: subprocess.run(command, shell=True, executable='/bin/bash', ...) Or detect the OS and adjust accordingly. 硕2104班 ***@***.*** 原始邮件 发件人：Xinlu Lai ***@***.***> 发件时间：2026年2月28日 00:44 收件人：shareAI-lab/learn-claude-code ***@***.***> 抄送：lei-zhenyu ***@***.***>, Author ***@***.***> 主题：Re: [shareAI-lab/learn-claude-code] Web simulator shows incorrectecho command for s01 demo (Issue #40) CrazyBoyM left a comment (shareAI-lab/learn-claude-code#40) Thanks for the report. However, in standard bash/zsh, the command: ```sh echo 'print("Hello, World!")' > hello.py ``` writes `print("Hello, World!")` to the file -- the single quotes are shell syntax (preventing interpretation of the double quotes), not part of the output. You can verify: ```sh $ echo 'print("Hello, World!")' > hello.py $ cat hello.py print("Hello, World!") ``` This might behave differently on Windows `cmd.exe` (which doesn't strip single quotes), but the web simulator and the agent code target bash. Could you share the exact environment where you reproduced this? If it's specifically a Windows/Git Bash issue, we can note it in the docs. 感谢报告。在标准 bash/zsh 中，单引号是 shell 语法不会写入文件。可能在 Windows cmd.exe 下行为不同。能否提供具体的复现环境？ — Reply to this email directly, view it on GitHub, or unsubscribe. You are receiving this because you authored the thread.