fix: Pty4j with JLine in raw mode does indeed avoid Shell echo

[vorburger]

Fixes #1410 & #1411.

See JetBrains/pty4j#170.

[gemini-code-assist]

Hello @vorburger, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

Summary of Changes

As gemini-code-assist, I've analyzed this pull request. The core purpose of this change is to address and demonstrate a fix for an issue where using Pty4j in conjunction with JLine resulted in unwanted double echoing of input from the shell. The PR confirms that enabling JLine's raw mode (terminal.enterRawMode()) is the correct approach to prevent the shell from echoing, contrary to previous assumptions noted in the code's comments. This change updates the Demo.java example to correctly use raw mode and cleans up outdated comments and TODOs.

Highlights

• Fix Shell Echo Issue: This pull request provides a fix and demonstration for the issue of double echoing when using Pty4j with JLine. It confirms that entering JLine's raw mode (terminal.enterRawMode()) successfully prevents the shell from echoing input, resolving issues Pty4j Shell echo #1410 and Pty4j Cursor Up/Down & Backspace etc. #1411.
• Update Demo Implementation: The Demo.java file is updated to correctly enable raw mode for the JLine terminal and remove comments that suggested this approach was ineffective or problematic.
• Code Cleanup: Outdated TODO comments and a commented-out print statement are removed from the Demo.java file, improving code clarity.

Changelog

• java/dev/enola/common/exec/pty/Demo.java
  • Enabled JLine raw mode (terminal.enterRawMode()) in the main method to correctly handle shell input without double echoing.
  • Removed comments indicating that raw mode or terminal.echo(false) did not fix the echo issue.
  • Added a comment referencing the related pty4j issue chore(deps): update dependency mkdocs-material to v9.1.12 #170 for context.
  • Removed a commented-out System.out.println line.
  • Removed TODO comments related to system(false) and systemOutput.

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---

Shell speaks too loud,
Raw mode silences the crowd,
Just one echo now.

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[gemini-code-assist]

Code Review

This pull request effectively addresses the shell echo issue when using Pty4j with JLine by correctly configuring the terminal in raw mode. The changes simplify the Demo.java class, remove outdated TODOs and misleading comments, and introduce a clear explanation for the behavior of terminal.echo() in raw mode. The core fix, involving the use of TerminalBuilder.builder().build() (which defaults to system(false)) and terminal.enterRawMode(), appears to be well-targeted and resolves the problems mentioned in issues #1410, #1411, and the linked pty4j issue.

Summary of Findings

• Successful Fix Implementation: The primary change of enabling raw mode via terminal.enterRawMode() and adjusting the TerminalBuilder configuration (by removing .system(true), thus defaulting to system(false)) successfully resolves the reported shell echo problem. This aligns with the findings in the linked pty4j issue.
• Code Clarity and Cleanup: The removal of previous TODO comments related to the echo issue, along with a commented-out debug line, improves the overall clarity and maintainability of the Demo.java class. The previous, apparently incorrect, comment advising against raw mode has also been removed, reflecting the new, correct approach.
• Informative Comment Added: The new comment // NB: terminal.echo() true or false makes no difference (because we're in raw mode) is a valuable addition, clarifying the terminal's behavior in raw mode and potentially preventing future confusion.

Merge Readiness

The changes in this pull request are clear, directly address the intended fix, and improve the codebase. Based on this review, the code appears to be in good shape and ready for merging. As I am an AI, I am not authorized to approve pull requests; please ensure it undergoes any further necessary review processes before merging.