Picocli: Command Line History Accessible via Up Arrow

[aspearman]

Is it possible to access previous command history using Picocli? Like how a regular terminal can toggle through previous commands using the up arrow?

If not, this would be an excellent feature to add!

[remkop]

This is a good feature to add to a picocli-based interactive shell (#242). Nice idea!

[aspearman]

Okay, is there some sort of a workaround for now? I'm not sure how to implement it.

Maybe capture raw input and append it to a list of previous commands before I send the input to CommandLine? In which case command line history is totally independent of picocli.

Yeah, it really would be nice to have this in-built.

[remkop]

The upcoming picocli 3.0 release will have a new class ParseResult which has the original input. An application could keep references to these ParseResult objects to maintain a history.

There’s work in progress (#293) to provide a command tokenizer which will be an important building block for an interactive shell. To be honest, I haven’t given this area much thought yet other than what is happening on #293. This may grow in the future.

[BeeeWall]

I'll look into something for this at some point, hopefully this week because it is spring break here. It would probably be in the new picocli.interactive package, or the normal one?

[remkop]

Nice! picocli.interactive would be the right package.

[remkop]

With #497 there is now a new module picocli-jline2-shell where I plan to add functionality and documentation for building interactive shells with JLine 2 and picocli. As a starting point there will be a completer that dynamically completes the command in a JLine shell based on the picocli CommandSpec. Future interactive shell functionality should go into this module.

As for the topic of this ticket, JLine 2 includes some functionality for command line history, so I will close this ticket when I release the picocli-jline2 module, but feel free to re-open if this requires refinement.

[remkop]

Looks like I forgot to close this.
I believe that JLine has built-in support for navigating through the history of executed commands with the up/down arrow keys.