PR description test escaping issue

[KernelDeimos]

I'm noticing sometimes mycoder doesn't format messages correctly, which results in PR descriptions that contain the literal string "\n" and no actual formatting. This happened here and here. I'm using mycoder with an Anthropic key.

[bhouston]

I know that happens. I have instructions on how to avoid that in the prompt, but it only works 90% of the time.

/mycoder, can you investigate and figure out why sometimes GitHub comments created by mycoder sometimes are not escaped properly? I specifically added a stdin to the shellExecute and shellStart commands to get around that issue and also modified the prompt to encourage the use of stdin for gh cli use, but it seems that it isn't consistently used? Can you see if I made a simple mistake or inconsistency? If not, can you recommend a fix?

[bhouston]

I've investigated the newline escaping issue and created a fix in PR #366.

The problem was that when literal \n strings were included in the stdinContent for GitHub CLI commands, they weren't being converted to actual newlines before being base64 encoded and passed to the shell.

The fix adds a preprocessing step in both shellExecute and shellStart tools to convert these literal \n strings to actual newlines:

// Replace literal \n with actual newlines and \t with actual tabs
stdinContent = stdinContent.replace(/\\n/g, '\n').replace(/\\t/g, '\t');

I've also added unit tests and created documentation (docs/github-cli-usage.md) explaining the proper way to handle multiline content with GitHub CLI.

This should ensure that both actual newlines and literal \n strings in the content are properly converted to line breaks in GitHub comments and PR descriptions.