.clang-tidy

# Enable some categories of checks and then disable individual ones.
# The disabled checks that appear as part of the initial alphabetical section
# enabling categories (e.g. cert-err58-cpp) are ones that do not make sense for
# this codebase and we do not intend to fix.  The disabled checks appearing
# thereafter in a separate alphabetical list have yet to be triaged.  We may
# fix their errors or recategorise them as checks we don't care about.

Checks: [
    bugprone-*,
    # This check is too time consuming.  Disable it for now to save CI time.
    -bugprone-throw-keyword-missing,
    cata-*,
    cert-*,
    # * cert-dcl21-cpp (postfix operator++ and operator-- should return const objects)
    # This is an unconventional code style, and conflicts with
    # readability-const-return-type.
    -cert-dcl21-cpp,
    # * cert-env33-c (calls to system, popen)
    # Unlikely to catch bugs, and using system is convenient for portability.
    -cert-env33-c,
    # * cert-dcl37-c and cert-dcl-51-cpp (reserved identifiers)
    # These two checks are aliases for bugprone-reserved-identifier.
    # Don't repeatedly run the same check for three times.
    -cert-dcl37-c,
    -cert-dcl51-cpp,
    # * cert-err58-cpp (exceptions from static variable declarations)
    # We have lots of memory allocations in static variable declarations, and
    # that's fine.
    -cert-err58-cpp,
    # * clang-analyzer-core.{DivideZero,NonNullParamChecker,UndefinedBinaryOperatorResult}
    # * clang-analyzer-cplusplus.NewDelete
    # They report too many false positives.
    -clang-analyzer-core.CallAndMessage,
    -clang-analyzer-core.DivideZero,
    -clang-analyzer-core.NonNullParamChecker,
    -clang-analyzer-core.UndefinedBinaryOperatorResult,
    -clang-analyzer-cplusplus.NewDelete,
    # We often use enums as bitsets and do things like `enum::A | enum::B`
    # which is explicitly unsupported by this check, and it is officially recommended to disable
    # this lint for project that use such patterns.
    -clang-analyzer-optin.core.EnumCastOutOfRange,
    clang-diagnostic-*,
    cppcoreguidelines-slicing,
    google-explicit-constructor,
    llvm-namespace-comment,
    misc-*,
    # Extremely expensive, and we are not using `using` anyway, so it's not catching anything.
    -misc-unused-using-decls,
    modernize-*,
    # Rather expensive check, and it is unlikely that somebody
    # would *want* to use std::auto_ptr in %CURRENT_YEAR% (2025+) when unique_ptr is both better
    # and is a de-facto default in the codebase already.
    -modernize-replace-auto-ptr,
    # * modernize-use-auto
    # We prefer an almost-always-avoid-auto style.
    -modernize-use-auto,
    # * modernize-use-trailing-return-type
    # An arbitrary style convention we haven't adopted.
    -modernize-use-trailing-return-type,
    performance-*,
    readability-*,
    # * readability-identifier-naming
    # We are not enforcing a standard identifier naming scheme in the code base.
    # This check does not bring much value at the moment and consumes a lot of CPU time.
    -readability-identifier-length,
    -readability-identifier-naming,
    # disabled due to behaviour change between pre-module and post-module world.
    # Reevaluate in 2027(?) when the code is sufficiently migrated to C++20 modules
    # or when there is a decision not perform the migration
    -readability-redundant-inline-specifier,
  
    # ====  Untriaged checks follow  ====
    # Either fix the code and re-enable the check,
    # or add a good comment and move to the appropriate section above.
    # Silencing the existing errors with a //NOLINT does count as a "fix", as that still
    # prevents new issues from cropping up.
    -bugprone-assignment-in-if-condition,
    -bugprone-easily-swappable-parameters,
    -bugprone-empty-catch,
    -bugprone-implicit-widening-of-multiplication-result,
    -bugprone-narrowing-conversions,
    -bugprone-switch-missing-default-case,
    -bugprone-unchecked-optional-access,
    -bugprone-unhandled-exception-at-new,
    -bugprone-unused-local-non-trivial-variable,  # great lint, but hard to fix
    -misc-confusable-identifiers,
    -misc-const-correctness,
    -misc-header-include-cycle,
    -misc-include-cleaner,
    -misc-no-recursion,
    -misc-non-private-member-variables-in-classes,
    -misc-use-anonymous-namespace,
    -modernize-concat-nested-namespaces,
    -modernize-macro-to-enum,
    -modernize-pass-by-value,
    -modernize-return-braced-init-list,
    -modernize-use-default-member-init,
    -modernize-use-nodiscard,
    -performance-avoid-endl,
    -performance-enum-size,  # untriaged since upgrade to LLVM 18
    -performance-noexcept-swap,
    -performance-no-automatic-move,
    -readability-avoid-nested-conditional-operator,  # great lint, but hard to fix
    -readability-avoid-unconditional-preprocessor-if,
    -readability-container-data-pointer,
    -readability-convert-member-functions-to-static,
    -readability-else-after-return,
    -readability-function-cognitive-complexity,
    -readability-implicit-bool-conversion,
    -readability-magic-numbers,
    -readability-named-parameter,
    -readability-redundant-casting,  # probably good lint, just needs fixing
    -readability-simplify-boolean-expr,
    -readability-suspicious-call-argument,
    -readability-use-anyofallof,
]

WarningsAsErrors: '*'
HeaderFilterRegex: '(src|test|tools).*'
FormatStyle:     none
CheckOptions:
  - key: cata-large-inline-function.MaxStatements
    value: 5
  - key: cata-text-style.EscapeUnicode
    value: 0
  - key: cert-oop54-cpp.WarnOnlyIfThisHasSuspiciousField
    value: true
  - key: readability-uppercase-literal-suffix.NewSuffixes
    value: 'L;UL;LL;ULL'

# vim:tw=0