fix: update monitor settings only if it's changed

[kittaakos]

Depends on #1662

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Motivation

Do not send monitor settings changes when there are no settings updates.

Change description

I wanted to keep the changeset as small as possible. From now on, setSettings promise resolves with undefined if there are no effective monitor settings updates. In such a case, the IDE2 monitor service does not send a MonitorRequest to the CLI.

Other information

Closes #375

Reviewer checklist

• PR addresses a single concern.
• The PR has no duplicates (please search among the Pull Requests before creating one)
• PR title and description are properly filled.
• Docs have been added / updated (for bug fixes / features)

[palazzol]

@kittaakos: I tried this commit in my branch, and it seems to work great. The only remaining issue in the IDE with #375 is that, when you change the baud rate from the serial monitor pulldown, there are still 6 CONFIGURE commands sent out instead of only the one for the baud rate. I believe the issue is here: https://github.com/arduino/arduino-ide/blob/theia-1.31.1/arduino-ide-extension/src/browser/serial/monitor/monitor-widget.tsx#L237 Instead of only sending the baud rate, it looks like this code grabs all the serial settings, updates the baud rate, and then sends them all out. I tested the serial-plotter as well, and it acts the same way when you change the baud rate.

[kittaakos]

Thank you for the handy input, @palazzol 💪 Could you please check the tester build from my updated PR?

I completely rewrote my proposed changes: this time, IDE2 calculates a diff of monitor settings and sends only a diff of configuration commands.

Thank you!

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When starting the monitor, IDE2 sends the configure commands:

2022-11-28T14:28:30.203Z daemon INFO INFO[0016] Starting monitor process                      monitor=serial-monitor

2022-11-28T14:28:30.207Z daemon INFO INFO[0016] Monitor process started successfully!         monitor=serial-monitor
INFO[0016] sending command                               command="HELLO 1 \"arduino-cli 0.29.0\"" monitor=serial-monitor

2022-11-28T14:28:30.211Z daemon INFO INFO[0016] received message                              error=false event_type=hello message=OK monitor=serial-monitor
INFO[0016] sending command                               command=DESCRIBE monitor=serial-monitor

2022-11-28T14:28:30.212Z daemon INFO INFO[0016] received message                              error=false event_type=describe message=OK monitor=serial-monitor
INFO[0016] sending command                               command="CONFIGURE dtr on" monitor=serial-monitor
INFO[0016] received message                              error=false event_type=configure message=OK monitor=serial-monitor
INFO[0016] sending command                               command="CONFIGURE parity none" monitor=serial-monitor
INFO[0016] received message                              error=false event_type=configure message=OK monitor=serial-monitor
INFO[0016] sending command                               command="CONFIGURE rts on" monitor=serial-monitor
INFO[0016] received message                              error=false event_type=configure message=OK monitor=serial-monitor
INFO[0016] sending command                               command="CONFIGURE stop_bits 1" monitor=serial-monitor

2022-11-28T14:28:30.213Z daemon INFO INFO[0016] received message                              error=false event_type=configure message=OK monitor=serial-monitor
INFO[0016] sending command                               command="CONFIGURE baudrate 9600" monitor=serial-monitor
INFO[0016] received message                              error=false event_type=configure message=OK monitor=serial-monitor
INFO[0016] sending command                               command="CONFIGURE bits 8" monitor=serial-monitor
INFO[0016] received message                              error=false event_type=configure message=OK monitor=serial-monitor
INFO[0016] sending command                               command="OPEN 127.0.0.1:49640 /dev/cu.usbmodem14301" monitor=serial-monitor

2022-11-28T14:28:30.216Z daemon INFO INFO[0016] received message                              error=false event_type=open message=OK monitor=serial-monitor

2022-11-28T14:28:30.216Z daemon INFO INFO[0016] Port /dev/cu.usbmodem14301 successfully opened 

2022-11-28T14:28:30.219Z monitor-service INFO Using port configuration for serial:/dev/cu.usbmodem14301: {"settingsList":[{"settingId":"dtr","value":"on"},{"settingId":"parity","value":"none"},{"settingId":"rts","value":"on"},{"settingId":"stop_bits","value":"1"},{"settingId":"baudrate","value":"9600"},{"settingId":"bits","value":"8"}]}
2022-11-28T14:28:30.219Z monitor-service INFO started monitor to /dev/cu.usbmodem14301 using serial

When changing the baud rate, only the baud rate is configured:

2022-11-28T14:29:14.679Z monitor-service INFO Updated the port configuration for serial:/dev/cu.usbmodem14301: {"settingsList":[{"settingId":"dtr","value":"on"},{"settingId":"parity","value":"none"},{"settingId":"rts","value":"on"},{"settingId":"stop_bits","value":"1"},{"settingId":"baudrate","value":"4800"},{"settingId":"bits","value":"8"}]}
2022-11-28T14:29:14.679Z monitor-service INFO Sending monitor request with new port configuration: {"settingsList":[{"settingId":"baudrate","value":"4800"}]}
2022-11-28T14:29:14.680Z daemon INFO INFO[0060] sending command                               command="CONFIGURE baudrate 4800" monitor=serial-monitor

2022-11-28T14:29:14.681Z daemon INFO INFO[0060] received message                              error=false event_type=configure message=OK monitor=serial-monitor

When changing the line ending, it's a NOOP:

2022-11-28T14:30:23.139Z monitor-service INFO No port configuration changes have been detected. No need to send configure commands to the running monitor serial:/dev/cu.usbmodem14301.

[palazzol]

I tried the tester build and it seems to work very well - thanks for doing this! I do find it odd that when changing one parameter, the information about which parameter has changed gets "lost" somehow and needs to be regenerated by diffing at another level. But, I don't really understand to full communications path - and these changes do seem to fix the issue.

[kittaakos]

I tried the tester build and it seems to work very well

Great!

thanks for doing this!

You provided excellent support and helped me understand the problem. I appreciate your help.

I do find it odd that when changing one parameter, the information about which parameter has changed gets "lost" somehow and needs to be regenerated by diffing at another level.

I agree. IDE2 deserves better logic. I am unfamiliar with the monitor code, but I wanted to chime in after your #1677 (comment). I am happy we could find a point where we can work around the bug without eventually changing the monitor behavior.

[AlbyIanna]

LGTM code-wise

[per1234]

I verified this fixes one component of #375

changing the selection in the line ending menu triggers the immediate sending of additional spurious data in addition to the regular periodic data reported above.

I notice the same happens when you toggle the "Toggle Autoscroll" or "Toggle Timestamp" icons.

---

The other component of #375, where spurious data is sent periodically even without a settings change has been fixed upstream via bugst/go-serial#147 + arduino/serial-monitor#31 and will reach Arduino IDE 2.x users without any need for action in this repository once the next release of serial-monitor is made.

Thanks Akos and @palazzol!