style/cpp/.clang-tidy

Checks: '
    -*,
    bugprone-unchecked-optional-access,
    readability-function-size,
    readability-function-cognitive-complexity
'
CheckOptions:
  - { key: readability-function-size.LineThreshold,             value: 60 } # [1]
  - { key: readability-function-size.ParameterThreshold,        value: 6 }  # [2]
  - { key: readability-function-cognitive-complexity.Threshold, value: 25 } # [3]

WarningsAsErrors: '*'
HeaderFilterRegex: '(?!^subprojects).*'

# [1] https://isocpp.github.io/CppCoreGuidelines/CppCoreGuidelines#f3-keep-functions-short-and-simple
# [2] https://isocpp.github.io/CppCoreGuidelines/CppCoreGuidelines#f2-a-function-should-perform-a-single-logical-operation
# [3] https://isocpp.github.io/CppCoreGuidelines/CppCoreGuidelines#f3-keep-functions-short-and-simple
# However cognitive complexity != cyclomatic complexity. Therefore using the clang-tidy default value,
# as cyclomatic complexity seems to not be implemented in clang-tidy.

# [1],[2],[3] do not have to be enforced or applied project-wide yet.