[terminal] Support an API to notify the command execution is done in terminal

[jdneo]

Let's make sure issue is not already fixed in latest builds first.

• I verified latest Integration Build of Eclipse SDK doesn't provide the feature.

Suggestion

I hope to collect the output of a command execution in the terminal, thus I need a signal to let my plugin knows the execution is done.

Community

• I understand suggesting an enhancement doesn't mandate anyone to implement it. Other contributors may consider this suggestion, or not, at their own convenience. The most efficient way to get it fixed is that I implement it myself and contribute it back as a good quality patch to the project.

[iloveeclipse]

Could you provide a simple snippet how you open Terminal and execute command?

[jdneo]

How we launch the terminal:

https://github.com/eclipse-copilot/eclipse-copilot/blob/9fc215b436968b7b7274048e7e8c2dc837a75ccd/org.eclipse.copilot.ui/src/org/eclipse/copilot/ui/chat/tools/RunInTerminalTool.java#L198-L213

How we parse the output:

https://github.com/eclipse-copilot/eclipse-copilot/blob/9fc215b436968b7b7274048e7e8c2dc837a75ccd/org.eclipse.copilot.ui/src/org/eclipse/copilot/ui/chat/tools/RunInTerminalTool.java#L319-L360

TBH, the logic of parsing the output is too tricky and almost un-maintainable.

[laeubi]

@jdneo I fear this does not work well... you are pasting a string to the terminal (what could be anything e.g echo that is not a command at all) so how should there be any API for this?

I assume you want this to work independent of OS as well.

So my main question would be why do you use a shell and pasting text commands? It would be easier for you to create an own process with a terminal attached....

[jdneo]

Thank you @laeubi

Could you give more pointers about It would be easier for you to create an own process with a terminal attached....?

[laeubi]

Okay, first some background:

What you refer as "Terminal" here has two parts and is actually a "Local Terminal Emulation":

1. a UI what basically is VT100TerminalControl
2. a shell, usually bash/sh or similar under linux/mac and cmd in windows that accepts some string and execute them in the context of the shell but you can configure this:

So what happens is we start a new process with the commandinterpreter of the OS and then you can type in text commands. What exactly is working is of course highly OS dependent, e.g. under linux you can use <whatever> & to start a new process in background and on windows you would use start <whatever>. Then with your method you can inject such strings that ultimately result in starting a new process and usually the in/out is piped to the commandinterpreter (unless e.g. you do <whatever> > stdout.txt or similar!)

So as you can see "when command finish" and "collect its output" is highly dependent on how you start the command, some commands might never exit and some outputs might never show up in the UI! Maybe even output of such things are interleaved!

---

-- SNIP --

Now for your question, with the "Terminal Console" we do a different approach, we have a command X and execute it inside a terminal session as a process so we get:

1. Direct in/out/error streams
2. Exit codes
3. and show that in an own UI

You can find this approach here: https://github.com/eclipse-platform/eclipse.platform/tree/master/debug/org.eclipse.debug.terminal

keep in mind, that with that approach while you can possibly reuse the UI part you need to spawn a new process for each command you execute and you can not use any features of the shell e.g. property expansion.

[laeubi]

NB: I used copilot to generate this docu https://github.com/eclipse-platform/eclipse.platform/blob/master/terminal/README.md

Maybe it helps or you like to enhance it with specific questions / information. Beside that it might even work to implement an own terminal connector as well (e.g. Copilot Terminal)

[jdneo]

Thank you @laeubi for the guidance.

The debug terminal approach seems promising. Though I'm not sure whether features like property expansion is important for LLM or not, my assumption is that this is not a hard requirement.

Or at least I can maybe made a preference to configure the mode how terminal is launched.

[laeubi]

@jdneo just let us know when you face any issues, just assume I don't know maybe nothing how you issue commands, e.g. is copilot really issuing command on my local machine like ls-l or cat <whatever> and parsing its outputs?

[jdneo]

@jdneo just let us know when you face any issues, just assume I don't know maybe nothing how you issue commands, e.g. is copilot really issuing command on my local machine like ls-l or cat <whatever> and parsing its outputs?

Yes, we will send the real command to the terminal and use ITerminalServiceOutputStreamMonitorListener to collect the output content from the terminal. When we guess the execution is finished, we send back all the output to LLM.

---

I just realize that there will be one problem for the debug terminal solution: since it's creating new process for each command execution, the state of the execution will lose.

The LLM may generate new command based on last output, for example, it can first cd to a dir, and then run a command. If we always creating a new process, the state like working directory is lost.

[iloveeclipse]

I wonder if you can start bash as a wrapper inside terminal? Then all processes will run in same shell and you can decide based on output whether some task is done or not?

[jdneo]

@iloveeclipse

Not sure if I understand your question.

For windows, we use cmd.exe as the shell command. For MacOS and Linux, we do not set the shell command, so it should fallback to use /bin/sh

Then all processes will run in same shell and you can decide based on output whether some task is done or not?

Parsing the output to check if the task is done or not is almost impossible, given the different behavior of different Platform and shell. That is why I wish to have an API that clearly tell the plugin the command execution is done.

[LorenzoBettini]

For sure, I'm missing all the internal details, so apologies if I oversimplify.
Isn't the Java Process enough to run a command and wait for its termination?
One can capture the output of the Process and print it in the terminal as a visual result, but the real command is executed on a Java process on which you have full control, independently of the running system or shell.

[jdneo]

Hi @LorenzoBettini,

See the second part of this comment: #2270 (comment).

Imagine this case:

1. Copilot runs cd xxx, changes the directory, and it assume you are already in that directory after that.
2. Copilot runs some command under that directory.

Spawning a new java process to run a command may lose such kind of states.