.clang-tidy configuration files appear to be ignored by CCS. Only checks specifically defined in the IDE (workspace/project level settings) are recognized. If no checks are specified, then clang-tidy is simply not run, despite the presence of a .clang-tidy file in the project.

Note that if clang-tidy is explicitly run in the project directory with --list-checks, it will look for and find any checks in a .clang-tidy file in the project or parent workspace.

https://clang.llvm.org/extra/clang-tidy/#id2