clang-tidy: add option CMake_RUN_CLANG_TIDY

.clang-tidy

+---
+Checks: "-*,\
+misc-*,\
+-misc-incorrect-roundings,\
+-misc-macro-parentheses,\
+-misc-misplaced-widening-cast,\
+-misc-static-assert,\
+modernize-make-shared,\
+modernize-make-unique,\
+modernize-redundant-void-arg,\
+modernize-use-bool-literals,\
+modernize-use-nullptr,\
+modernize-use-override,\
+performance-*,\
+-performance-inefficient-string-concatenation,\
+readability-*,\
+-readability-function-size,\
+-readability-identifier-naming,\
+-readability-implicit-bool-cast,\
+-readability-inconsistent-declaration-parameter-name,\
+-readability-named-parameter,\
+-readability-redundant-declaration,\
+-readability-redundant-member-init,\
+-readability-simplify-boolean-expr,\
+"
+HeaderFilterRegex: 'Source/cm[^/]*\.(h|hxx|cxx)$'
+CheckOptions:
+  - key:    modernize-use-nullptr.NullMacros
+    value:  'CM_NULLPTR'
+...

CMakeLists.txt

@@ -226,6 +226,20 @@ option(CMAKE_USE_FOLDERS "Enable folder grouping of projects in IDEs." ON)
 mark_as_advanced(CMAKE_USE_FOLDERS)
 
 
+option(CMake_RUN_CLANG_TIDY "Run clang-tidy with the compiler." OFF)
+if(CMake_RUN_CLANG_TIDY)
+  if(CMake_SOURCE_DIR STREQUAL CMake_BINARY_DIR)
+    message(FATAL_ERROR "CMake_RUN_CLANG_TIDY requires an out-of-source build!")
+  endif()
+  find_program(CLANG_TIDY_COMMAND NAMES clang-tidy)
+  if(NOT CLANG_TIDY_COMMAND)
+    message(FATAL_ERROR "CMake_RUN_CLANG_TIDY is ON but clang-tidy is not found!")
+  endif()
+  set(CMAKE_CXX_CLANG_TIDY "${CLANG_TIDY_COMMAND}")
+endif()
+configure_file(.clang-tidy .clang-tidy COPYONLY)
+
+
 option(CMake_RUN_IWYU "Run include-what-you-use with the compiler." OFF)
 if(CMake_RUN_IWYU)
   find_program(IWYU_COMMAND NAMES include-what-you-use iwyu)

Utilities/.clang-tidy

+---
+# We want to disable all checks for 3rd party code.  However, clang-tidy will
+# assume we did not configure it correctly.  Just add one check that will never
+# be found.
+Checks: '-*,llvm-twine-local'
+...

Utilities/CMakeLists.txt

@@ -29,3 +29,6 @@ endif()
 if(WIX_CUSTOM_ACTION_ENABLED)
   add_subdirectory(Release/WiX)
 endif()
+
+# Make sure generated files use the same clang-tidy checks (none).
+configure_file(.clang-tidy .clang-tidy COPYONLY)