.clang-tidy

# Follow .clang-format for formatting
FormatStyle: file
# GN doesn't support -isystem so Clang-Tidy doesn't know which headers belong
# to us when applying checks/fixes. Set that here.
HeaderFilterRegex: '^(src|include|third_party/emdawnwebgpu)/.*)'

Checks:
  # List of checks: https://clang.llvm.org/extra/clang-tidy/checks/list.html
  # Checks can be locally disabled with NOLINT/NOLINTNEXTLINE.

  # Enable all checks, then disable irrelevant groups.
  - "*"
  - -altera-*                 # OpenCL
  - -boost-*                  # Usages of Boost
  - -linuxkernel-*            # Internals of Linux kernel
  - -llvm-*                   # Internals of LLVM
  - -llvmlibc-*               # Internals of libc
  - -openmp-*                 # OpenMP

  # Disable clang-analyzer checks because loading even one of them is VERY slow.
  # TODO(https://crbug.com/501491694): We should investigate running
  # clang-analyzer somewhere. It seems to run more than just these checks.
  - -clang-analyzer-*

  # Checks that were estimated as P0/P1 are not disabled even though the code is
  # not "clean" of them. It's useful for them to keep triggering on new changes.
  # https://crbug.com/548071770 tracks fixing existing check failures.
  # P2+ are disabled for now to reduce noise.

  ## P0. Most likely to help with hardening.
  #- -readability-inconsistent-declaration-parameter-name  # in webgpu.h and src/tint
  ## - Other memory safety
  #- -bugprone-casting-through-void
  #- -bugprone-return-const-ref-from-parameter
  #- -bugprone-sizeof-expression
  #- -cppcoreguidelines-owning-memory
  ## - Arithmetic (crbug.com/515527144/dependencies)
  #- -bugprone-integer-division
  #- -bugprone-misplaced-widening-cast
  #- -bugprone-narrowing-conversions
  #- -bugprone-too-small-loop-variable
  #- -modernize-use-integer-sign-comparison  # has fixits, but in most cases we'll want to fix this another way (fix types so they match)

  ## P1. Likely to help with hardening.
  #- -bugprone-easily-swappable-parameters
  #- -bugprone-forwarding-reference-overload
  #- -bugprone-move-forwarding-reference
  #- -bugprone-suspicious-memory-comparison
  #- -bugprone-suspicious-stringview-data-usage
  #- -bugprone-undefined-memory-manipulation
  #- -bugprone-unhandled-self-assignment
  #- -bugprone-unintended-char-ostream-output
  #- -bugprone-use-after-move
  #- -cppcoreguidelines-pro-bounds-pointer-arithmetic
  #- -cppcoreguidelines-slicing
  #- -cppcoreguidelines-virtual-class-destructor  # has multiple fixit alternatives
  #- -misc-misplaced-const
  #- -modernize-use-ranges  # has fixits
  #- -modernize-use-string-view  # has fixits
  #- -readability-reference-to-constructed-temporary
  #- -readability-suspicious-call-argument

  # P2. Might help with hardening.
  - -android-cloexec-*
  - -bugprone-crtp-constructor-accessibility
  - -bugprone-macro-parentheses
  - -bugprone-multi-level-implicit-pointer-conversion
  - -bugprone-signed-bitwise
  - -bugprone-string-constructor
  - -cppcoreguidelines-owning-memory
  - -cppcoreguidelines-pro-bounds-array-to-pointer-decay
  - -cppcoreguidelines-pro-bounds-constant-array-index
  - -cppcoreguidelines-pro-type-const-cast
  - -cppcoreguidelines-pro-type-static-cast-downcast
  - -cppcoreguidelines-pro-type-union-access
  - -cppcoreguidelines-pro-type-vararg
  - -cppcoreguidelines-special-member-functions
  - -google-default-arguments
  - -misc-confusable-identifiers
  - -modernize-avoid-c-arrays
  - -modernize-use-designated-initializers  # Note this would require ~20k fixes!
  - -modernize-use-nodiscard
  - -portability-no-assembler
  - -readability-else-after-return
  - -readability-implicit-bool-conversion
  - -readability-redundant-casting
  - -readability-simplify-boolean-expr
  # - Enums (crbug.com/515562283)
  - -bugprone-invalid-enum-default-initialization
  - -bugprone-switch-missing-default-case
  - -cppcoreguidelines-use-enum-class
  ## - These are commented out so we'll get warnings on new changes.
  #- -bugprone-copy-constructor-init
  #- -concurrency-mt-unsafe
  #- -cppcoreguidelines-interfaces-global-init
  #- -misc-new-delete-overloads

  # P3. Checks that could be nice, but probably don't help with hardening.
  - -bugprone-lambda-function-name
  - -bugprone-random-generator-seed
  - -bugprone-unchecked-optional-access
  - -cppcoreguidelines-macro-usage
  - -cppcoreguidelines-pro-type-reinterpret-cast
  - -fuchsia-statically-constructed-objects
  - -fuchsia-virtual-inheritance
  - -google-objc-avoid-nsobject-new
  - -google-readability-namespace-comments
  - -misc-const-correctness
  - -misc-include-cleaner
  - -misc-multiple-inheritance
  - -misc-non-private-member-variables-in-classes
  - -misc-override-with-different-visibility
  - -misc-predictable-rand
  - -misc-use-internal-linkage
  - -modernize-avoid-variadic-functions
  - -modernize-pass-by-value
  - -modernize-type-traits
  - -modernize-use-constraints
  - -modernize-use-equals-default
  - -modernize-use-equals-delete
  - -modernize-use-scoped-lock
  - -modernize-use-structured-binding
  - -modernize-use-using
  - -performance-*
  - -readability-avoid-const-params-in-decls
  - -readability-duplicate-include  # issue with d3d headers?
  - -readability-redundant-qualified-alias
  - -readability-redundant-qualified-alias
  - -readability-redundant-typename
  ## - These are commented out so we'll get warnings on new changes.
  #- -bugprone-forward-declaration-namespace
  #- -bugprone-nondeterministic-pointer-iteration-order
  #- -bugprone-unused-local-non-trivial-variable
  #- -cppcoreguidelines-avoid-const-or-ref-data-members
  #- -cppcoreguidelines-avoid-non-const-global-variables
  #- -cppcoreguidelines-no-malloc
  #- -cppcoreguidelines-prefer-member-initializer
  #- -google-runtime-int
  #- -misc-unconventional-assign-operator
  #- -modernize-concat-nested-namespaces
  #- -modernize-deprecated-headers
  #- -modernize-loop-convert
  #- -modernize-macro-to-enum  # Need to suppress in opengl_platform_autogen.h
  #- -modernize-make-unique
  #- -modernize-min-max-use-initializer-list
  #- -modernize-use-bool-literals
  #- -modernize-use-default-member-init
  #- -modernize-use-starts-ends-with
  #- -portability-template-virtual-member-function

  # P4. Checks we may or may not want to enable eventually.
  - -abseil-faster-strsplit-delimiter
  - -abseil-string-find-startswith
  - -abseil-string-find-str-contains
  - -bugprone-branch-clone  # In practice doesn't seem to find anything useful
  - -bugprone-unhandled-code-paths  # Probably not that useful, but can be silenced with a comment somehow if desired
  - -cppcoreguidelines-avoid-do-while
  - -cppcoreguidelines-avoid-goto  # Used by GTest
  - -google-build-using-namespace  # Probably just needs NOLINTs
  - -google-runtime-float  # `long double` used in Tint to handle literals
  - -misc-no-recursion
  - -misc-non-private-member-variables-in-classes
  - -misc-use-anonymous-namespace
  - -modernize-raw-string-literal
  - -modernize-return-braced-init-list
  - -modernize-use-auto
  - -modernize-use-emplace
  - -modernize-use-std-format  # Remove if we switch from absl::StrFormat to std::format
  - -modernize-use-std-numbers
  - -modernize-use-transparent-functors
  - -readability-avoid-const-params-in-decls
  - -readability-redundant-lambda-parameter-list
  - -readability-redundant-nested-if

  # P∞. Checks we're not really interested in re-enabling.
  - -bugprone-throwing-static-initialization  # We don't have exceptions, so nothing throws
  # -ftrivial-auto-var-init = pattern (debug) or zero (release) is enabled across chrome build, which addresses uninitialized issues of POD variables.
  - -cppcoreguidelines-init-variables
  # - Appears unnecessary since we use hardened libc++.
  - -cppcoreguidelines-pro-bounds-avoid-unchecked-container-access
  # - Clang already catches the more problematic cases (& with ==, etc.) in
  #   various warnings, so in practice this only triggers on multiplication
  #   (*%/) with addition (+-) which isn't a concern.
  - -readability-math-missing-parentheses
  # - Various style things we're not interested in.
  - -cppcoreguidelines-missing-std-forward               # We don't mind moving a value into a function for it to be dropped at the end.
  - -cppcoreguidelines-rvalue-reference-param-not-moved  # We don't mind moving a value into a function for it to be dropped at the end.
  - -fuchsia-trailing-return  # Buggy: docs say this isn't supposed to trigger on lambdas, but it does.
  - -google-objc-global-variable-declaration  # Triggers when using GTest.
  - -google-readability-avoid-underscore-in-googletest-name  # Used all the time in Tint. Doesn't add anything
  - -misc-redundant-expression  # In practice only triggers in macros and generated code.
  - -misc-unused-parameters  # Not really useful and can be handled by Clang if needed.
  - -modernize-redundant-void-arg  # Doesn't matter, triggers once on webgpu.h
  - -modernize-use-trailing-return-type  # We don't prefer trailing return types.
  - -readability-inconsistent-ifelse-braces  # Handled by clang-format instead.
  - -readability-redundant-lambda-parameter-list  # We don't prefer [] {} over []() {} for lambdas with no arguments.
  - -readability-uppercase-literal-suffix  # Tint uses primarily lower case, so triggers a lot.
  - -readability-use-concise-preprocessor-directives  # We don't prefer #ifdef over #if defined.
  # - Zircon kernel code style checks.
  - -fuchsia-default-arguments-calls
  - -fuchsia-default-arguments-declarations
  - -fuchsia-overloaded-operator
  - -fuchsia-temporary-objects
  - -zircon-temporary-objects

  # P?. Untriaged checks that weren't passing on a first-pass over the codebase.
  # TODO(https://crbug.com/548071770): Estimate priorities for all of these.
  - -readability-avoid-nested-conditional-operator
  - -readability-avoid-return-with-void-value
  - -readability-braces-around-statements
  - -readability-const-return-type
  - -readability-container-contains
  - -readability-container-data-pointer
  - -readability-container-size-empty
  - -readability-convert-member-functions-to-static
  - -readability-enum-initial-value
  - -readability-fn_size
  - -readability-function-cognitive-complexity
  - -readability-function-size
  - -readability-identifier-length
  - -readability-isolate-declaration
  - -readability-magic-numbers
  - -readability-make-member-function-const
  - -readability-named-parameter
  - -readability-non-const-parameter
  - -readability-qualified-auto
  - -readability-redundant-access-specifiers
  - -readability-redundant-control-flow
  - -readability-redundant-declaration
  - -readability-redundant-inline-specifier
  - -readability-redundant-member-init
  - -readability-redundant-parentheses
  - -readability-redundant-preprocessor
  - -readability-redundant-smartptr-get
  - -readability-redundant-string-cstr
  - -readability-redundant-string-init
  - -readability-static-accessed-through-instance
  - -readability-static-definition-in-anonymous-namespace
  - -readability-trailing-comma
  - -readability-trivial-switch
  - -readability-use-anyofallof
  - -readability-use-std-min-max

  # Aliases of other checks. If ANY of the names of a check is enabled, it will
  # run. So we can blanket disable everything that says its an alias, EXCEPT
  # for those which are in groups we disable.
  # https://clang.llvm.org/extra/clang-tidy/checks/list.html#check-aliases
  - -cert-arr39-c                                               # bugprone-sizeof-expression
  - -cert-con36-c                                               # bugprone-spuriously-wake-up-functions
  - -cert-con54-cpp                                             # bugprone-spuriously-wake-up-functions
  - -cert-ctr56-cpp                                             # bugprone-pointer-arithmetic-on-polymorphic-object
  - -cert-dcl03-c                                               # misc-static-assert
  - -cert-dcl16-c                                               # readability-uppercase-literal-suffix
  - -cert-dcl37-c                                               # bugprone-reserved-identifier
  - -cert-dcl50-cpp                                             # modernize-avoid-variadic-functions
  - -cert-dcl51-cpp                                             # bugprone-reserved-identifier
  - -cert-dcl54-cpp                                             # misc-new-delete-overloads
  - -cert-dcl58-cpp                                             # bugprone-std-namespace-modification
  - -cert-dcl59-cpp                                             # misc-anonymous-namespace-in-header
  - -cert-env33-c                                               # bugprone-command-processor
  - -cert-err09-cpp                                             # misc-throw-by-value-catch-by-reference
  - -cert-err33-c                                               # bugprone-unused-return-value
  - -cert-err34-c                                               # bugprone-unchecked-string-to-number-conversion
  - -cert-err52-cpp                                             # modernize-avoid-setjmp-longjmp
  - -cert-err58-cpp                                             # bugprone-throwing-static-initialization
  - -cert-err60-cpp                                             # bugprone-exception-copy-constructor-throws
  - -cert-err61-cpp                                             # misc-throw-by-value-catch-by-reference
  - -cert-exp42-c                                               # bugprone-suspicious-memory-comparison
  - -cert-exp45-c                                               # bugprone-assignment-in-selection-statement
  - -cert-fio38-c                                               # misc-non-copyable-objects
  - -cert-flp30-c                                               # bugprone-float-loop-counter
  - -cert-flp37-c                                               # bugprone-suspicious-memory-comparison
  - -cert-int09-c                                               # readability-enum-initial-value
  - -cert-mem57-cpp                                             # bugprone-default-operator-new-on-overaligned-type
  - -cert-msc24-c                                               # bugprone-unsafe-functions
  - -cert-msc30-c                                               # misc-predictable-rand
  - -cert-msc32-c                                               # bugprone-random-generator-seed
  - -cert-msc33-c                                               # bugprone-unsafe-functions
  - -cert-msc50-cpp                                             # misc-predictable-rand
  - -cert-msc51-cpp                                             # bugprone-random-generator-seed
  - -cert-msc54-cpp                                             # bugprone-signal-handler
  - -cert-oop11-cpp                                             # performance-move-constructor-init
  - -cert-oop54-cpp                                             # bugprone-unhandled-self-assignment
  - -cert-oop57-cpp                                             # bugprone-raw-memory-call-on-non-trivial-type
  - -cert-oop58-cpp                                             # bugprone-copy-constructor-mutates-argument
  - -cert-pos44-c                                               # bugprone-bad-signal-to-kill-thread
  - -cert-pos47-c                                               # concurrency-thread-canceltype-asynchronous
  - -cert-sig30-c                                               # bugprone-signal-handler
  - -cert-str34-c                                               # bugprone-signed-char-misuse
  - -cppcoreguidelines-avoid-c-arrays                           # modernize-avoid-c-arrays
  - -cppcoreguidelines-avoid-magic-numbers                      # readability-magic-numbers
  - -cppcoreguidelines-c-copy-assignment-signature              # misc-unconventional-assign-operator
  - -cppcoreguidelines-explicit-constructor                     # misc-explicit-constructor
  - -cppcoreguidelines-explicit-virtual-functions               # modernize-use-override
  - -cppcoreguidelines-macro-to-enum                            # modernize-macro-to-enum
  - -cppcoreguidelines-narrowing-conversions                    # bugprone-narrowing-conversions
  - -cppcoreguidelines-noexcept-destructor                      # performance-noexcept-destructor
  - -cppcoreguidelines-noexcept-move-operations                 # performance-noexcept-move-constructor
  - -cppcoreguidelines-noexcept-swap                            # performance-noexcept-swap
  - -cppcoreguidelines-non-private-member-variables-in-classes  # misc-non-private-member-variables-in-classes
  - -cppcoreguidelines-use-default-member-init                  # modernize-use-default-member-init
  - -fuchsia-header-anon-namespaces                             # misc-anonymous-namespace-in-header
  - -fuchsia-multiple-inheritance                               # misc-multiple-inheritance
  - -google-build-namespaces                                    # misc-anonymous-namespace-in-header
  #- -google-explicit-constructor                                # misc-explicit-constructor
  - -google-readability-braces-around-statements                # readability-braces-around-statements
  - -google-readability-casting                                 # modernize-avoid-c-style-cast
  - -google-readability-function-size                           # readability-function-size
  - -hicpp-uppercase-literal-suffix                             # readability-uppercase-literal-suffix
  - -llvm-else-after-return                                     # readability-else-after-return
  - -llvm-qualified-auto                                        # readability-qualified-auto
  - -performance-faster-string-find                             # performance-prefer-single-char-overloads
  # - TODO(https://crbug.com/501491694): We currently use
  #   NOLINTNEXTLINE(google-explicit-constructor) instead of
  #   misc-explicit-constructor. Now that we enable just one copy of each check,
  #   we should eventually switch to misc-explicit-constructor (remove this line
  #   and re-add the google-explicit-constructor alias to the list above).
  - -misc-explicit-constructor

CheckOptions:
  - key: cppcoreguidelines-avoid-do-while.IgnoreMacros
    value: true
  - key: readability-implicit-bool-conversion.AllowIntegerConditions
    value: true
  - key: readability-implicit-bool-conversion.AllowPointerConditions
    value: true
  - key: bugprone-assert-side-effect.AssertMacros
    value: assert,NSAssert,NSCAssert,DAWN_ASSERT,DAWN_RELEASE_ASSUME
    # It would be nice to use bugprone-assert-side-effect.CheckFunctionCalls,
    # but it isn't smart enough and triggers on things like:
    # - constexpr functions like std::numeric_limits::max()
    # - templated methods https://github.com/llvm/llvm-project/issues/62878
  - key: bugprone-reserved-identifier.AllowedIdentifiers
    value: "_"  # Used when we alias GTest's ::testing::_ into global namespace.
  - key: google-readability-todo.Style
    value: Parentheses
  - key: cppcoreguidelines-pro-type-member-init.UseAssignment
    value: true