Provide the analysis tools our CI images carry: `clang-tidy` to run the
checks in `.clang-tidy`, `clang-tools` for `scan-build`, and `clazy`, the
compiler our Clazy job builds with.
Name the version of `clang-tidy` our checks are written against rather
than install Ubuntu's unversioned package, which is a release behind and
reports `cmake-use-cmsys-fstream` where it should not. `CMakeLists.txt`
searches for `clang-tidy` only under the unversioned name, so link the
version installed by name to it, as we already do for `clang-format`.
`clazy` and `clang-tools` remain whatever versions Ubuntu carries rather
than the ones the CI image does, so expect their diagnostics to differ
from those jobs'. CMake's own clang-tidy checks are not available either
way: `CMake_USE_CLANG_TIDY_MODULE` needs `Utilities/ClangTidyModule` built
against Clang's development files, which are not installed here.
Suggested-by: Tyler Yankee <tyler.yankee@kitware.com>
Provide a `.devcontainer` definition, following the Dev Container
Specification, to give contributors a ready-made Linux environment with
the tools needed to build CMake, run its test suite, build its
documentation, and satisfy its style rules.
Base the container on Ubuntu, which offers the broadest ecosystem of
packages and tooling for development, including a recent `cmake` and the
`clang-format` version our style rules require, exactly. Mirror the
package lists of the Debian image our CI infrastructure uses, section by
section, so that the dependencies available closely match the ones
against which merge requests are tested. Build the image the way the
images under `.gitlab/ci/docker/` are built: bind mount the package
lists and the installation script rather than copying them in, and cache
the package lists and downloaded archives so that a rebuild fetches only
what has changed.
Run optional `.devcontainer/hooks/root.sh` and
`.devcontainer/hooks/user.sh` scripts, both ignored by Git, so that
developers may customize the container without modifying tracked files.
Document usage in a new `Help/dev/devcontainer.rst`.
Fixes: #28043
Taylor Braun-Jones