This pull request is in conflict. Could you fix it @TSNoble?

@sjahr @sea-bass

I believe this is ready for review now. Summary, since the thread is quite long:

• I've replaced all .h files with .hpp (except ikfast and the autogenerated exports)
• I've added #pragma once to headers which were missing them
• I've added a script which autogenerates .h files from .hpp files (with BSD-3, Authoriship, and non-warning deprecation msg)
• I've run this manually over the source tree and committed the .h files
• The only files I wasn't able to generate .h files for were ones that aren't being installed (tests, default_capabilities, moveit_py)
• Hopefully, the passing CI pipelines show that the imports work internally
• Hopefully, the passing Tutorial pipelines show that the imports work externally
• I'd think I'd like to include auto-gen of headers in the CI, but this can wait until we've seen the method works well, and with some tweaks / improvements
• I still think we should upgrade these imports to warnings, and eventually remove the headers, however, I agree it'd be unwise to do so on short notice, without informing downstream repositories:
  • It might be useful to raise an issue with a hard deadline to turn these into warnings, with some kind of announcement?
  • And the same for removing support for c-style headers entirely
• Failing humble build seems to be unrelated (resolved)

@sea-bass

Would you mind running the humble-ci job on this PR again when #3130 is resolved, just to make sure everything passes?

You should merge this so my email inbox can rest again 😆

@sea-bass

I've applied your suggestions now (and tidied up the script a little more, and made the output a little nicer). I'd also be in favour of merging this soon so we can deal with any merge conflicts with other PRs quickly, but I also understand if you want to wait until the maintainer meeting tomorrow

I suggest adding a bit more context to the autogenerated message at the top of the h files. Your changelog notes are very descriptive, how about we use the:

/* This file was autogenerated by create_deprecated_headers.py */ becomes /* All MoveIt 2 headers have been updated to use the .hpp extension. .h headers are now autogenerated with a deprecation warning, and may be removed in future releases. Please update your imports to use the .hpp headers. See https://github.com/moveit/moveit2/pull/3113 for details. */

@nbbrooks

Thanks for the suggestion. I've modified the script (with a few tweaks to the formatting for readability & consistency with the BSD-3 comments), and have regenerated the header files.

/*********************************************************************
 * All MoveIt 2 headers have been updated to use the .hpp extension.
 *
 * .h headers are now autogenerated via create_deprecated_headers.py,
 * and will import the corresponding .hpp with a deprecation warning.
 *
 * imports via .h files may be removed in future releases, so please
 * modify your imports to use the corresponding .hpp imports.
 *
 * See https://github.com/moveit/moveit2/pull/3113 for extra details.
 *********************************************************************/

After this is merged, I'll likely look at tackling the outstanding headers listed in #857 as smaller, more targeted, (and more review-friendly) PRs 😄

@sea-bass

Humble tests failed on the merge queue with what looks like #3130 😢

Ah yes I need to merge the other PR first. One sec

I'm gonna go ahead and merge this since the deprecation warning in #3139 just snuck in today and I want to keep things moving for now.