Feature request: `compile --show-properties` without a sketch

[obra]

arduino-cli compile --show-properties currently won't run without an .ino file present. However, that appears to be a side effect of the fact that it's an option to compile

Using arduino-cli in my tooling, I often want to query board properties before locating a specific sketch. (This may be crazy.)

I -sort of- feel like --show-properties should be a sub-command of arduino-cli board, rather than compile. (And, if we're going there, I'd love it if there were a command like:

./bin/arduino-cli board get-property foo.bar --fqbn arduino:avr:leonardo

which would return the fully evaluated template for foo.bar.

[ubidefeo]

@obra
this looks interesting.
What do you think about it, @per1234 ? I saw you added the labels, which makes me think you agree :)

[per1234]

I actually think it would be cool if it were a global flag, since the properties are context-dependent. If you are compiling a sketch, build.project_name and build.source.path will be defined. If you are uploading, serial.port and serial.port.file, if doing upload -P or burn-bootloader then the properties of the programmer are defined.

[obra]

Just to further explain how I'm using this in my build tooling, these are the current shell functions I use to get an individual property.

_arduino_prop() {
        pref=$1
        # Strip the preference name. And then strip leading and trailing quotations
        _arduino_props | grep --max-count=1 "${pref}=" | sed -e s/^.*"${pref}"=// -e 's/^"//' -e 's/"$//'
}

_arduino_props() {
        if [ "x${_ARDUINO_PREFS}x" == "xx" ]; then
                _ARDUINO_PREFS=$(_run_arduino_cli --fqbn "${FQBN}" compile --show-properties "${SKETCH_FILE_PATH}")
        fi
        echo "$_ARDUINO_PREFS"
}


Here are some of my current uses:

 

We have a target that builds a .hex including the sketch and the bootloader

"${BOOTLOADER_PATH:=$(_arduino_prop 'runtime.platform.path')/bootloaders/$(_arduino_prop 'bootloader.file')}"```

# A custom board property used in the flashing process

flashing_instructions=$(_arduino_prop 'build.flashing_instructions')```