.clang-tidy

---
# Configure clang-tidy for this project.

# Here is an explanation for why some of the checks are disabled:
#
#  -google-readability-namespace-comments: the *_CLIENT_NS is a macro, and
#      clang-tidy fails to match it against the initial value.
#
#  -modernize-use-trailing-return-type: clang-tidy recommends using
#      `auto Foo() -> std::string { return ...; }`, we think the code is less
#      readable in this form.
#
#  --modernize-concat-nested-namespaces: clang-tidy recommends
#      `namespace google::cloud {}` over `namespace google { namespace cloud { } }`
#      We need to support C++14, which does not supported nested namespaces.
#
#  --modernize-use-nodiscard: clang-tidy recommends adding a nodiscard annotation
#      to functions where the return value should not be ignored.
#      We need to support C++14, which does not supported the annotation.
#
#  -modernize-return-braced-init-list: We think removing typenames and using
#      only braced-init can hurt readability.
#
#  -modernize-avoid-c-arrays: We only use C arrays when they seem to be the
#      right tool for the job, such as `char foo[] = "hello"`. In these cases,
#      avoiding C arrays often makes the code less readable, and std::array is
#      not a drop-in replacement because it doesn't deduce the size.
#
#  -performance-move-const-arg: This warning requires the developer to
#      know/care more about the implementation details of types/functions than
#      should be necessary. For example, `A a; F(std::move(a));` will trigger a
#      warning IFF `A` is a trivial type (and therefore the move is
#      meaningless). It would also warn if `F` accepts by `const&`, which is
#      another detail that the caller need not care about.
#
#  -performance-avoid-endl: we would like to turn this on, but there are too
#      many legitimate uses in our samples.
#
#  -readability-redundant-declaration: A friend declaration inside a class
#      counts as a declaration, so if we also declare that friend outside the
#      class in order to document it as part of the public API, that will
#      trigger a redundant declaration warning from this check.
#
#  -readability-function-cognitive-complexity: too many false positives with
#      clang-tidy-12. We need to disable this check in macros, and that setting
#      only appears in clang-tidy-13.
#
#  -bugprone-narrowing-conversions: too many false positives around
#      `std::size_t`  vs. `*::difference_type`.
#
#  -bugprone-easily-swappable-parameters: too many false positives.
#
#  -bugprone-implicit-widening-of-multiplication-result: too many false positives.
#     Almost any expression of the form `2 * variable` or `long x = a_int * b_int;`
#     generates an error.
#
#  -bugprone-unchecked-optional-access: too many false positives in tests.
#     Despite what the documentation says, this warning appears after
#     `ASSERT_TRUE(variable)` or `ASSERT_TRUE(variable.has_value())`.
#
#  -misc-include-cleaner: too many *true* positives. We need to clean up the
#    code, but we should do that over time, maybe per-directory, instead of
#    blocking the adoption of Clang 17 until it is all fixed.
#
Checks: >
  -abseil-*

  -android-*

  boost-use-to-string,

  bugprone-*,

  cert-dcl21-cpp,
  cert-dcl50-cpp,
  cert-dcl58-cpp,
  cert-env33-c,
  cert-err34-c,
  cert-err52-cpp,
  cert-err58-cpp,
  cert-err60-cpp,
  cert-flp30-c,
  cert-msc50-cpp,
  cert-msc51-cpp,

  clang-analyzer-apiModeling.StdCLibraryFunctions,
  clang-analyzer-apiModeling.TrustNonnull,
  clang-analyzer-apiModeling.google.GTest,
  clang-analyzer-core.CallAndMessage,
  clang-analyzer-core.DivideZero,
  clang-analyzer-core.DynamicTypePropagation,
  clang-analyzer-core.NonNullParamChecker,
  clang-analyzer-core.NonnilStringConstants,
  clang-analyzer-core.NullDereference,
  clang-analyzer-core.StackAddressEscape,
  clang-analyzer-core.UndefinedBinaryOperatorResult,
  clang-analyzer-core.VLASize,
  clang-analyzer-core.builtin.BuiltinFunctions,
  clang-analyzer-core.builtin.NoReturnFunctions,
  clang-analyzer-core.uninitialized.ArraySubscript,
  clang-analyzer-core.uninitialized.Assign,
  clang-analyzer-core.uninitialized.Branch,
  clang-analyzer-core.uninitialized.CapturedBlockVariable,
  clang-analyzer-core.uninitialized.UndefReturn,
  clang-analyzer-cplusplus.InnerPointer,
  clang-analyzer-cplusplus.Move,
  clang-analyzer-cplusplus.NewDelete,
  clang-analyzer-cplusplus.NewDeleteLeaks,
  clang-analyzer-cplusplus.SelfAssignment,
  clang-analyzer-deadcode.DeadStores,
  clang-analyzer-nullability.NullPassedToNonnull,
  clang-analyzer-nullability.NullReturnedFromNonnull,
  clang-analyzer-nullability.NullableDereferenced,
  clang-analyzer-nullability.NullablePassedToNonnull,
  clang-analyzer-nullability.NullableReturnedFromNonnull,
  clang-analyzer-optin.cplusplus.VirtualCall,
  clang-analyzer-optin.mpi.MPI-Checker,
  clang-analyzer-optin.osx.cocoa.localizability.EmptyLocalizationContextChecker,
  clang-analyzer-optin.osx.cocoa.localizability.NonLocalizedStringChecker,
  clang-analyzer-optin.performance.GCDAntipattern,
  clang-analyzer-optin.performance.Padding,
  clang-analyzer-optin.portability.UnixAPI,
  -clang-analyzer-osx.*
  clang-analyzer-security.FloatLoopCounter,
  clang-analyzer-security.insecureAPI.UncheckedReturn,
  clang-analyzer-security.insecureAPI.bcmp,
  clang-analyzer-security.insecureAPI.bcopy,
  clang-analyzer-security.insecureAPI.bzero,
  clang-analyzer-security.insecureAPI.getpw,
  clang-analyzer-security.insecureAPI.gets,
  clang-analyzer-security.insecureAPI.mkstemp,
  clang-analyzer-security.insecureAPI.mktemp,
  clang-analyzer-security.insecureAPI.rand,
  clang-analyzer-security.insecureAPI.strcpy,
  clang-analyzer-security.insecureAPI.vfork,
  clang-analyzer-unix.API,
  clang-analyzer-unix.Malloc,
  clang-analyzer-unix.MallocSizeof,
  clang-analyzer-unix.MismatchedDeallocator,
  clang-analyzer-unix.Vfork,
  clang-analyzer-unix.cstring.BadSizeArg,
  clang-analyzer-unix.cstring.NullArg,
  clang-analyzer-valist.CopyToSelf,
  clang-analyzer-valist.Uninitialized,
  clang-analyzer-valist.Unterminated,

  cppcoreguidelines-avoid-goto,
  cppcoreguidelines-interfaces-global-init,
  cppcoreguidelines-macro-usage,
  cppcoreguidelines-narrowing-conversions,
  cppcoreguidelines-no-malloc,
  cppcoreguidelines-owning-memory,
  cppcoreguidelines-pro-bounds-array-to-pointer-decay,
  cppcoreguidelines-pro-bounds-constant-array-index,
  cppcoreguidelines-pro-bounds-pointer-arithmetic,
  cppcoreguidelines-pro-type-const-cast,
  cppcoreguidelines-pro-type-cstyle-cast,
  cppcoreguidelines-pro-type-member-init,
  -cppcoreguidelines-pro-type-reinterpret-cast,
  cppcoreguidelines-pro-type-static-cast-downcast,
  cppcoreguidelines-pro-type-union-access,
  cppcoreguidelines-pro-type-vararg,
  cppcoreguidelines-slicing,
  cppcoreguidelines-special-member-functions,

  -fuchsia-default-arguments,
  fuchsia-multiple-inheritance,
  -fuchsia-overloaded-operator,
  fuchsia-restrict-system-includes,
  fuchsia-statically-constructed-objects,
  -fuchsia-trailing-return,
  fuchsia-virtual-inheritance,

  google-build-explicit-make-pair,
  google-build-namespaces,
  google-build-using-namespace,
  google-default-arguments,
  google-explicit-constructor,
  google-global-names-in-headers,
  -google-objc-avoid-throwing-exception,
  -google-objc-function-naming,
  -google-objc-global-variable-declaration,
  google-readability-avoid-underscore-in-googletest-name,
  google-readability-casting,
  google-readability-todo,
  google-runtime-int,
  google-runtime-operator,
  google-runtime-references,
  
  hicpp-avoid-goto,
  hicpp-exception-baseclass,
  -hicpp-multiway-paths-covered,
  hicpp-no-assembler,
  hicpp-signed-bitwise,

  -llvm-header-guard,
  llvm-include-order,
  llvm-namespace-comment,
  -llvm-twine-local,

  misc-*,
  -misc-unused-parameters,

  modernize-*,
  -modernize-use-nodiscard,

  -mpi-*

  -objc-*

  -openmp-*

  performance-*,

  readability-*,
  -readability-implicit-bool-conversion,
  -readability-magic-numbers,
  -readability-named-parameter,
  -readability-uppercase-literal-suffix,

  -zircon-temporary-objects
WarningsAsErrors: ''
HeaderFilterRegex: ''
AnalyzeTemporaryDtors: false
FormatStyle:     none
CheckOptions:
  - key:             misc-non-private-member-variables-in-classes.IgnoreClassesWithAllMemberVariablesBeingPublic
    value:           1