build: require libc++ and clang headers

[mizvekov]

Make CMakeLists.txt enforce the requirement for libc++ and the clang headers.

Otherwise, it's possible for configuration to succeed but produce a non-functional mrdocs, where the tests fail in non-obvious ways.

[cppalliance-bot]

An automated preview of the documentation is available at https://946.mrdocs.prtest2.cppalliance.org/index.html

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 84.42%. Comparing base (0a751ac) to head (cde1ab6).
⚠️ Report is 1 commits behind head on develop.

Additional details and impacted files

@@           Coverage Diff            @@
##           develop     #946   +/-   ##
========================================
  Coverage    84.42%   84.42%           
========================================
  Files          190      190           
  Lines        20565    20566    +1     
========================================
+ Hits         17362    17363    +1     
  Misses        3203     3203           

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[alandefreitas]

Make the CMakeLists.txt enforce that requirement.

The code might be flawed but it already enforces this requirement. This PR only changes the condition (it should be unconditional anyway).

[mizvekov]

Make the CMakeLists.txt enforce that requirement.

The code might be flawed but it already enforces this requirement. This PR only changes the condition (it should be unconditional anyway).

You can make both calls to find_package (LLVM, Clang) succeed, without specifying LLVM_ROOT at all, by specifying LLVM_DIR and Clang_DIR instead.

This makes configuration succeed, but it results in a non-functional installation and tests.

If you mean we should just unconditionally require those things instead, that also works for me.

[cppalliance-bot]

An automated preview of the documentation is available at https://946.mrdocs.prtest2.cppalliance.org/index.html

[alandefreitas]

You can make both calls to find_package (LLVM, Clang) succeed, without specifying LLVM_ROOT at all, by specifying LLVM_DIR and Clang_DIR instead

Yes. That's what I mean by "The code might be flawed".

In other words, this is more of a fix than a feature.

Also related, cmake is an invalid conventional commit type. The type would be build.

If you mean we should just unconditionally require those things instead, that also works for me

Yes. We don't need

if (MRDOCS_BUILD_TESTS OR MRDOCS_INSTALL)

There's no case where MrDocs does not depend on these headers.

To be honest, the condition MRDOCS_BUILD_TESTS OR MRDOCS_INSTALL is not that far from if (TRUE) in practice.

[mizvekov]

In other words, this is more of a fix than a feature.

Yes, that was the intention here, this is strictly a fix.

[cppalliance-bot]

An automated preview of the documentation is available at https://946.mrdocs.prtest2.cppalliance.org/index.html

[cppalliance-bot]

An automated preview of the documentation is available at https://946.mrdocs.prtest2.cppalliance.org/index.html