b2: update 'standard' recipe to match the newer 'portable'

[valgur]

TODO

• Empty package

[github-actions]

🤖 Beep Boop! This pull request is making changes to 'recipes/b2//'.

👋 @grafikrobot you might be interested. 😉

[ghost]

I detected other pull requests that are modifying b2/portable recipe:

• b2: add version 4.10.1 #18484
• b2: Support CXX from a VirtualBuildEnv #17882

This message is automatically generated by https://github.com/ericLemanissier/conan-center-conflicting-prs so don't hesitate to report issues/improvements there.

[grafikrobot]

AFAICT the changes you made are:

1. A bunch of style only changes. Why?
2. Adding compiler and build_type to settings. Why?
3. Using option_descriptions. Great!
4. Clearing of some cpp_info vars. Great!
5. Putting the old and new build code into one recipe by adding the _build_non_portable function and version check. Why?

I'm wondering why you did (1) as it just makes the history harder to follow.

I'm wondering why you did (2). As mentioned in the other comment.. This goes against an intentional choice.

Last, (5). I really don't understand the goal of this PR. Why complicate the new build and install mode with the old mode? Is there some use case or problem you are trying to fix?

[valgur]

1. A bunch of style only changes. Why?

Sorry, these were incidental and not really relevant. Reverted them.

2. Adding compiler and build_type to settings. Why?

Added these to match the current recommendation to always list all values and then remove the irrelevant settings in package_id(): https://github.com/conan-io/conan-center-index/blob/master/docs/adding_packages/conanfile_attributes.md#settings

5. Putting the old and new build code into one recipe by adding the _build_non_portable function and version check. Why?
   Last, (5). I really don't understand the goal of this PR. Why complicate the new build and install mode with the old mode? Is there some use case or problem you are trying to fix?

The intention behind this PR was (1) to eliminate unnecessary dead code in the repo by updating the standard recipe and really (2) to personally get some practice on how the environment variables should be handled in Conan v2 before starting work on migrating some of the more complex Autotools recipes.

I originally did not intend to modify the portable recipe at all, but the differences between the two recipes appeared to be quite small, so it made sense to merge them instead.

Anyway, I reverted the merge of the standard and portable recipes now and only kept minimal changes to the portable one. The standard recipe is now identical to portable with only the build() method differing. A minor benefit of keeping them separate is reducing the number of versions to build when the newer one gets updated, I suppose, since the list of versions is quite long.

[conan-center-bot]

Conan v1 pipeline ❌

Sorry, the system is under maintenance and it doesn't accept builds right now.
Please, check https://status.conan.io to obtain more information.
Thanks for your understanding and help with the Conan Center Index!

---

Conan v2 pipeline ❌

Note: Conan v2 builds may be required once they are on the v2 ready list

The v2 pipeline failed. Please, review the errors and note this will be required for pull requests to be merged in the near future.

See details:

Sorry, the system is under maintenance and it doesn't accept builds right now.
Please, check https://status.conan.io to obtain more information.
Thanks for your understanding and help with the Conan Center Index!

[valgur]

Closing temporarily to avoid unnecessary load on the CI. Will reopen when I'm actively working on the PR again.