Can't include quoted strings in --build-properties args

[obra]

I'm clearly doing something wrong, but I'm having a heck of a time figuring out how arduino-cli wants me to escape strings containing " marks in values passed to --build-properties.

A slightly cut down example:

$ export LOCAL_CFLAGS='"-I/tmp/x" "-I/tmp/y"'

$ arduino-cli compile --fqbn my:valid:fqbn --build-properties "compiler.cpp.extra_flags=$LOCAL_CFLAGS" Sketch.ino

Gets me:

Error: invalid argument "compiler.cpp.extra_flags= "-I/tmp/x" "-I/tmp/y"" for "--build-properties" flag: parse error on line 1, column 26: bare " in non-quoted-field

I've been through just about every permutation I can think of, but can't figure out the correct escaping to be able to pass a string containing a double-quote in as a value for --build-properties.

A search of github issues for arduino-cli doesn't seem to turn up anyone else who's run into this, which leads me to suggest that I'm just missing something really obvious.

Currently testing against arduino-cli v0.13 and v0.11 on macOS and Linux.

I initially reported this as https://forum.arduino.cc/index.php?topic=709766.msg4769079#msg4769079