Describe the request

It would be extremely useful if the CLI could automatically generate, after the library discovery phase, a set of macros that describe the presence in the build of each detected library and its version.

There are several reasons:

• libraries could auto-configure depending on the presence of other libs in the project
• versions would not need to be manually defined in code for each library
• it would be possible to test for any library version in the same way

Describe the current behavior

The CLI does not currently provide this information. Only the {includes} variable in the sketch/libraries compilation step may offer any clue.

Arduino CLI version

new ones

Operating system

N/A

Operating system version

OS independent

Additional context

A suitable solution would provide, when for example Bridge 1.2.3 is included, something like a -DFOUND_BRIDGE_LIB=0x010203 in a specific {lib_detect_macros} variable for expansion in build commands. It may also be as a @file if this would generate too many macros.

The identifiers would be generated with unequivocal rules (for example by converting the library name to a valid uppercase C slug) and the versions would need to be easily sortable.

Notes:

• it would be desirable to have this at core compile time as well, if possible. Not a deal breaker if the core can refer to libraries (Allow platforms to specify library dependencies #3110); in that case the library dependent changes may be moved to a core-supplied lib.
• libs whose version can't be identified could have 1 as their version, which translates to the lowest possible non-zero version 0.0.1
• multiple #defines can be added for the same lib, for example:
  • longer ones, including the author name, to remove potential ambiguities;
  • more info on discovery (e.g. suffixes _IN_SKETCHBOOK, _IN_CORE, _IN_PROFILE, _SCORE etc)

Issue checklist

• I searched for previous requests in the issue tracker
• I verified the feature was still missing when using the nightly build
• My request contains all necessary details