.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-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.
#
#  -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`.
#
Checks: >
  -*,
  bugprone-*,
  google-*,
  misc-*,
  modernize-*,
  performance-*,
  portability-*,
  readability-*,
  -google-readability-braces-around-statements,
  -google-readability-namespace-comments,
  -google-runtime-references,
  -misc-non-private-member-variables-in-classes,
  -modernize-return-braced-init-list,
  -modernize-use-trailing-return-type,
  -modernize-avoid-c-arrays,
  -performance-move-const-arg,
  -readability-braces-around-statements,
  -readability-magic-numbers,
  -readability-named-parameter,
  -readability-redundant-declaration,
  -readability-function-cognitive-complexity,
  -bugprone-narrowing-conversions

# Turn all the warnings from the checks above into errors.
WarningsAsErrors: "*"

HeaderFilterRegex: "(google/cloud/|generator/).*\\.h$"

CheckOptions:
  - { key: readability-identifier-naming.NamespaceCase,          value: lower_case }
  - { key: readability-identifier-naming.ClassCase,              value: CamelCase  }
  - { key: readability-identifier-naming.StructCase,             value: CamelCase  }
  - { key: readability-identifier-naming.TemplateParameterCase,  value: CamelCase  }
  - { key: readability-identifier-naming.FunctionCase,           value: aNy_CasE  }
  - { key: readability-identifier-naming.VariableCase,           value: lower_case }
  - { key: readability-identifier-naming.ClassMemberCase,        value: lower_case }
  - { key: readability-identifier-naming.ClassMemberSuffix,      value: _          }
  - { key: readability-identifier-naming.PrivateMemberSuffix,    value: _          }
  - { key: readability-identifier-naming.ProtectedMemberSuffix,  value: _          }
  - { key: readability-identifier-naming.EnumConstantCase,         value: CamelCase }
  - { key: readability-identifier-naming.EnumConstantPrefix,       value: k         }
  - { key: readability-identifier-naming.ConstexprVariableCase,    value: CamelCase }
  - { key: readability-identifier-naming.ConstexprVariablePrefix,  value: k         }
  - { key: readability-identifier-naming.GlobalConstantCase,       value: CamelCase }
  - { key: readability-identifier-naming.GlobalConstantPrefix,     value: k         }
  - { key: readability-identifier-naming.MemberConstantCase,       value: CamelCase }
  - { key: readability-identifier-naming.MemberConstantPrefix,     value: k         }
  - { key: readability-identifier-naming.StaticConstantCase,       value: CamelCase }
  - { key: readability-identifier-naming.StaticConstantPrefix,     value: k         }
  - { key: readability-implicit-bool-conversion.AllowIntegerConditions,  value: 1   }
  - { key: readability-implicit-bool-conversion.AllowPointerConditions,  value: 1   }