[CMake][CTE] Add "check-clang-extra-..." targets to test only a particular Clang extra tool

[whisperity]

Summary

Create targets check-clang-tools-clang-tidy, check-clang-tools-clang-query similar to how check-clang-sema, check-clang-parser, etc. are auto-generated from the directory structure.

This allows running only a particular sub-tool's tests, not having to wait through the entire check-clang-tools's execution.

[lebedev.ri]

Thank you, this would be very helpful.

[whisperity]

@lebedev.ri If you have an idea on who's competent in accepting this change, please update the reviewers field, I'm in the dark here.

Also, should the commands be called check-clang-tools-clang-tidy or check-clang-extra-clang-tidy instead?

[whisperity]

After using this for a while, it feels more natural and more obvious that these are the CTE targets, not the "clang/tools" test targets.

[whisperity]

Ping. Can this go in? Still using this on a local fork, and still feels nice to be able to specify just a single tool.

[lebedev.ri]

LGTM, please feel free to land this as-is.

[njames93]

Just a follow up on this point, dependencies are a little messed up here. Running any of the check-clang-extra<...> results in all clang-tools-extra targets being built.
Not ideal if you just want to test a small change to one tools and potentially having to rebuild all extra-tools
Is this an artefact of how check-clang-tools also depends on all clang-tools-extra targets.

[whisperity]

In D84176#2300488, @njames93 wrote:

Is this an artefact of how check-clang-tools also depends on all clang-tools-extra targets.

Yes, this was not changed in this patch. Fixing that will require a lot more CMake magic which I did not have sufficient time to do so. We'd need to refactor the code which generates the initial targets for the subprojects, etc.
So yeah, the new build entry-point only gives you the benefit of not running the tests. Build list is equal to the normal check-clang-tools target.

clang-tools-extra/test/CMakeLists.txt

 
 add_lit_testsuite(check-clang-tools "Running the Clang extra tools' regression tests"
   ${CMAKE_CURRENT_BINARY_DIR}
   DEPENDS ${CLANG_TOOLS_TEST_DEPS}
   ARGS ${CLANG_TOOLS_TEST_EXTRA_ARGS}
   )
 
 set_target_properties(check-clang-tools PROPERTIES FOLDER "Clang extra tools' tests")
+
+add_lit_testsuites(CLANG-EXTRA ${CMAKE_CURRENT_SOURCE_DIR}
+  DEPENDS ${CLANG_TOOLS_TEST_DEPS}
+  )