diff options
Diffstat (limited to 'subprojects/lix-clang-tidy')
| -rw-r--r-- | subprojects/lix-clang-tidy/.clang-format | 1 | ||||
| -rw-r--r-- | subprojects/lix-clang-tidy/.editorconfig | 4 | ||||
| -rw-r--r-- | subprojects/lix-clang-tidy/FixIncludes.cc | 90 | ||||
| -rw-r--r-- | subprojects/lix-clang-tidy/FixIncludes.hh | 21 | ||||
| -rw-r--r-- | subprojects/lix-clang-tidy/HasPrefixSuffix.cc | 80 | ||||
| -rw-r--r-- | subprojects/lix-clang-tidy/HasPrefixSuffix.hh | 25 | ||||
| -rw-r--r-- | subprojects/lix-clang-tidy/LixClangTidyChecks.cc | 19 | ||||
| -rw-r--r-- | subprojects/lix-clang-tidy/README.md | 56 | ||||
| -rw-r--r-- | subprojects/lix-clang-tidy/default.nix | 44 | ||||
| -rw-r--r-- | subprojects/lix-clang-tidy/meson.build | 18 | ||||
| -rw-r--r-- | subprojects/lix-clang-tidy/meson.options | 3 |
11 files changed, 361 insertions, 0 deletions
diff --git a/subprojects/lix-clang-tidy/.clang-format b/subprojects/lix-clang-tidy/.clang-format new file mode 100644 index 000000000..cd8995543 --- /dev/null +++ b/subprojects/lix-clang-tidy/.clang-format @@ -0,0 +1 @@ +BasedOnStyle: llvm diff --git a/subprojects/lix-clang-tidy/.editorconfig b/subprojects/lix-clang-tidy/.editorconfig new file mode 100644 index 000000000..19ee09eec --- /dev/null +++ b/subprojects/lix-clang-tidy/.editorconfig @@ -0,0 +1,4 @@ +# LLVM style code is 2-space indented +[*.{cc,hh}] +indent_style = space +indent_size = 2 diff --git a/subprojects/lix-clang-tidy/FixIncludes.cc b/subprojects/lix-clang-tidy/FixIncludes.cc new file mode 100644 index 000000000..602d3d355 --- /dev/null +++ b/subprojects/lix-clang-tidy/FixIncludes.cc @@ -0,0 +1,90 @@ +#include "FixIncludes.hh" +#include <clang-tidy/ClangTidyCheck.h> +#include <clang/Basic/Diagnostic.h> +#include <clang/Basic/SourceManager.h> +#include <clang/Lex/PPCallbacks.h> +#include <clang/Lex/Preprocessor.h> +#include <llvm/ADT/StringRef.h> +#include <llvm/Support/Debug.h> +#include <memory> +#include <set> +#include <string> + +namespace nix::clang_tidy { + +using namespace clang; +using namespace clang::tidy; + +class FixIncludesCallbacks : public PPCallbacks { +public: + ClangTidyCheck &Check; + Preprocessor &PP; + FixIncludesCallbacks(ClangTidyCheck &Check, Preprocessor &PP) + : Check(Check), PP(PP) {} + +private: + bool Ignore = false; + virtual void LexedFileChanged(FileID FID, LexedFileChangeReason Reason, + SrcMgr::CharacteristicKind FileType, + FileID PrevFID, SourceLocation Loc) override; + + virtual void InclusionDirective(SourceLocation HashLoc, + const Token &IncludeTok, StringRef FileName, + bool IsAngled, CharSourceRange FilenameRange, + OptionalFileEntryRef File, + StringRef SearchPath, StringRef RelativePath, + const Module *Imported, + SrcMgr::CharacteristicKind FileType) override; +}; + +void FixIncludesCallbacks::LexedFileChanged(FileID, LexedFileChangeReason, + SrcMgr::CharacteristicKind FileType, + FileID, SourceLocation) { + Ignore = FileType != SrcMgr::C_User; +} + +void FixIncludesCallbacks::InclusionDirective( + SourceLocation, const Token &, StringRef FileName, bool IsAngled, + CharSourceRange FilenameRange, OptionalFileEntryRef File, StringRef, + StringRef, const Module *, SrcMgr::CharacteristicKind) { + if (Ignore) + return; + + // FIXME: this is kinda evil, but this is a one-time fixup + const std::vector<std::string> SourceDirs = {"src/", "include/lix/"}; + + const auto Bracketize = [IsAngled](StringRef s) { + return IsAngled ? ("<" + s + ">").str() : ("\"" + s + "\"").str(); + }; + + for (const auto &SourceDir : SourceDirs) { + const bool IsAlreadyFixed = FileName.starts_with("lix/lib"); + if (File && File->getNameAsRequested().contains(SourceDir) && + !IsAlreadyFixed) { + StringRef Name = File->getNameAsRequested(); + auto Idx = Name.find(SourceDir); + assert(Idx != std::string::npos); + std::string Suffix = Name.drop_front(Idx + SourceDir.length()).str(); + + if (!Suffix.starts_with("lib")) { + llvm::dbgs() << "ignored: " << Suffix << "\n"; + return; + } + + Suffix = "lix/" + Suffix; + + auto Diag = Check.diag(FilenameRange.getBegin(), + "include needs to specify the source subdir"); + + Diag << FilenameRange + << FixItHint::CreateReplacement(FilenameRange, Bracketize(Suffix)); + } + } +} + +void FixIncludesCheck::registerPPCallbacks(const SourceManager &, + Preprocessor *PP, Preprocessor *) { + PP->addPPCallbacks(std::make_unique<FixIncludesCallbacks>(*this, *PP)); +} + +}; // namespace nix::clang_tidy diff --git a/subprojects/lix-clang-tidy/FixIncludes.hh b/subprojects/lix-clang-tidy/FixIncludes.hh new file mode 100644 index 000000000..ea890cd39 --- /dev/null +++ b/subprojects/lix-clang-tidy/FixIncludes.hh @@ -0,0 +1,21 @@ +#pragma once +///@file + +#include <clang-tidy/ClangTidyCheck.h> +#include <clang/ASTMatchers/ASTMatchFinder.h> +#include <llvm/ADT/StringRef.h> + +namespace nix::clang_tidy { + +using namespace clang; +using namespace clang::tidy; + +class FixIncludesCheck : public ClangTidyCheck { + public: + FixIncludesCheck(StringRef Name, ClangTidyContext *Context) + : ClangTidyCheck(Name, Context) {} + + void registerPPCallbacks(const SourceManager &SM, Preprocessor *PP, Preprocessor *ModuleExpanderPP) override; +}; + +}; diff --git a/subprojects/lix-clang-tidy/HasPrefixSuffix.cc b/subprojects/lix-clang-tidy/HasPrefixSuffix.cc new file mode 100644 index 000000000..e29b67e7c --- /dev/null +++ b/subprojects/lix-clang-tidy/HasPrefixSuffix.cc @@ -0,0 +1,80 @@ +#include "HasPrefixSuffix.hh" +#include <clang/AST/ASTTypeTraits.h> +#include <clang/AST/Expr.h> +#include <clang/AST/PrettyPrinter.h> +#include <clang/AST/Type.h> +#include <clang/ASTMatchers/ASTMatchers.h> +#include <clang/Basic/Diagnostic.h> +#include <clang/Frontend/FrontendAction.h> +#include <clang/Frontend/FrontendPluginRegistry.h> +#include <clang/Tooling/Transformer/SourceCode.h> +#include <clang/Tooling/Transformer/SourceCodeBuilders.h> +#include <iostream> + +namespace nix::clang_tidy { +using namespace clang::ast_matchers; +using namespace clang; + +void HasPrefixSuffixCheck::registerMatchers(ast_matchers::MatchFinder *Finder) { + Finder->addMatcher( + traverse(clang::TK_AsIs, + callExpr(callee(functionDecl(anyOf(hasName("hasPrefix"), + hasName("hasSuffix"))) + .bind("callee-decl")), + optionally(hasArgument( + 0, cxxConstructExpr( + hasDeclaration(functionDecl(hasParameter( + 0, parmVarDecl(hasType( + asString("const char *"))))))) + .bind("implicit-cast")))) + .bind("call")), + this); +} + +void HasPrefixSuffixCheck::check( + const ast_matchers::MatchFinder::MatchResult &Result) { + + const auto *CalleeDecl = Result.Nodes.getNodeAs<FunctionDecl>("callee-decl"); + auto FuncName = std::string(CalleeDecl->getName()); + std::string NewName; + if (FuncName == "hasPrefix") { + NewName = "starts_with"; + } else if (FuncName == "hasSuffix") { + NewName = "ends_with"; + } else { + llvm_unreachable("nix-has-prefix: invalid callee"); + } + + const auto *MatchedDecl = Result.Nodes.getNodeAs<CallExpr>("call"); + const auto *ImplicitConvertArg = + Result.Nodes.getNodeAs<CXXConstructExpr>("implicit-cast"); + + const auto *Lhs = MatchedDecl->getArg(0); + const auto *Rhs = MatchedDecl->getArg(1); + auto Diag = diag(MatchedDecl->getExprLoc(), FuncName + " is deprecated"); + + std::string Text = ""; + + // Form possible cast to string_view, or nothing. + if (ImplicitConvertArg) { + Text = "std::string_view("; + Text.append(tooling::getText(*Lhs, *Result.Context)); + Text.append(")."); + } else { + Text.append(*tooling::buildAccess(*Lhs, *Result.Context)); + } + + // Call .starts_with. + Text.append(NewName); + Text.push_back('('); + Text.append(tooling::getText(*Rhs, *Result.Context)); + Text.push_back(')'); + + Diag << FixItHint::CreateReplacement(MatchedDecl->getSourceRange(), Text); + + // for (const auto *arg : MatchedDecl->arguments()) { + // arg->dumpColor(); + // arg->getType().dump(); + // } +} +}; // namespace nix::clang_tidy diff --git a/subprojects/lix-clang-tidy/HasPrefixSuffix.hh b/subprojects/lix-clang-tidy/HasPrefixSuffix.hh new file mode 100644 index 000000000..8693b6767 --- /dev/null +++ b/subprojects/lix-clang-tidy/HasPrefixSuffix.hh @@ -0,0 +1,25 @@ +#pragma once +///@file +/// This is an example of a clang-tidy automated refactoring against the Nix +/// codebase. The refactoring has been completed in +/// https://gerrit.lix.systems/c/lix/+/565 so this code is around as +/// an example. + +#include <clang-tidy/ClangTidyCheck.h> +#include <clang/ASTMatchers/ASTMatchFinder.h> +#include <llvm/ADT/StringRef.h> + +namespace nix::clang_tidy { + +using namespace clang; +using namespace clang::tidy; +using namespace llvm; + +class HasPrefixSuffixCheck : public ClangTidyCheck { +public: + HasPrefixSuffixCheck(StringRef Name, ClangTidyContext *Context) + : ClangTidyCheck(Name, Context) {} + void registerMatchers(ast_matchers::MatchFinder *Finder) override; + void check(const ast_matchers::MatchFinder::MatchResult &Result) override; +}; +}; // namespace nix::clang_tidy diff --git a/subprojects/lix-clang-tidy/LixClangTidyChecks.cc b/subprojects/lix-clang-tidy/LixClangTidyChecks.cc new file mode 100644 index 000000000..b3503dd3a --- /dev/null +++ b/subprojects/lix-clang-tidy/LixClangTidyChecks.cc @@ -0,0 +1,19 @@ +#include <clang-tidy/ClangTidyModule.h> +#include <clang-tidy/ClangTidyModuleRegistry.h> +#include "FixIncludes.hh" +#include "HasPrefixSuffix.hh" + +namespace nix::clang_tidy { +using namespace clang; +using namespace clang::tidy; + +class NixClangTidyChecks : public ClangTidyModule { + public: + void addCheckFactories(ClangTidyCheckFactories &CheckFactories) override { + CheckFactories.registerCheck<HasPrefixSuffixCheck>("lix-hasprefixsuffix"); + CheckFactories.registerCheck<FixIncludesCheck>("lix-fixincludes"); + } +}; + +static ClangTidyModuleRegistry::Add<NixClangTidyChecks> X("lix-module", "Adds lix specific checks"); +}; diff --git a/subprojects/lix-clang-tidy/README.md b/subprojects/lix-clang-tidy/README.md new file mode 100644 index 000000000..c2d1cb258 --- /dev/null +++ b/subprojects/lix-clang-tidy/README.md @@ -0,0 +1,56 @@ +# Clang tidy lints for Lix + +This is a skeleton of a clang-tidy lints library for Lix. + +Currently there is one check (which is already obsolete as it has served its +goal and is there as an example), `HasPrefixSuffixCheck`. + +## Running fixes/checks + +One file: + +``` +ninja -C build && clang-tidy --checks='-*,lix-*' --load=build/liblix-clang-tidy.so -p ../compile_commands.json -header-filter '\.\./src/.*\.h' --fix ../src/libcmd/installables.cc +``` + +Several files, in parallel: + +``` +ninja -C build && run-clang-tidy -checks='-*,lix-*' -load=build/liblix-clang-tidy.so -p .. -header-filter '\.\./src/.*\.h' -fix ../src | tee -a clang-tidy-result +``` + +## Resources + +* https://firefox-source-docs.mozilla.org/code-quality/static-analysis/writing-new/clang-query.html +* https://clang.llvm.org/docs/LibASTMatchersReference.html +* https://devblogs.microsoft.com/cppblog/exploring-clang-tooling-part-3-rewriting-code-with-clang-tidy/ + +## Developing new checks + +Put something like so in `myquery.txt`: + +``` +set traversal IgnoreUnlessSpelledInSource +# ^ Ignore implicit AST nodes. May need to use AsIs depending on how you are +# working. +set bind-root true +# ^ true unless you use any .bind("foo") commands +set print-matcher true +enable output dump +match callExpr(callee(functionDecl(hasName("hasPrefix"))), optionally(hasArgument( 0, cxxConstructExpr(hasDeclaration(functionDecl(hasParameter(0, parmVarDecl(hasType(asString("const char *"))).bind("meow2")))))))) +``` + +Then run, e.g. `clang-query --preload hasprefix.query -p compile_commands.json src/libcmd/installables.cc`. + +With this you can iterate a query before writing it in C++ and suffering from +C++. + +### Tips and tricks for the C++ + +There is a function `dump()` on many things that will dump to stderr. Also +`llvm::errs()` lets you print to stderr. + +When I wrote `HasPrefixSuffixCheck`, I was not really able to figure out how +the structured replacement system was supposed to work. In principle you can +describe the replacement with a nice DSL. Look up the Stencil system in Clang +for details. diff --git a/subprojects/lix-clang-tidy/default.nix b/subprojects/lix-clang-tidy/default.nix new file mode 100644 index 000000000..1bfc2d9a4 --- /dev/null +++ b/subprojects/lix-clang-tidy/default.nix @@ -0,0 +1,44 @@ +{ + lib, + stdenv, + cmake, + meson, + ninja, + llvmPackages, +}: +let + inherit (lib) fileset; +in +stdenv.mkDerivation { + pname = "lix-clang-tidy-checks"; + # Setting the version to the Lix version is just going to cause pointless + # rebuilds due to versionSuffix and similar, and I cannot conceive of a usage + # where we actually care about its version since this is internal-only. + version = "0.1"; + + src = fileset.toSource { + root = ./.; + fileset = fileset.unions [ + ./meson.build + ./meson.options + (fileset.fileFilter ( + { hasExt, ... }: + builtins.any hasExt [ + "cc" + "hh" + ] + ) ./.) + ]; + }; + + nativeBuildInputs = [ + meson + cmake + ninja + ]; + + buildInputs = [ + llvmPackages.llvm + llvmPackages.clang-unwrapped.dev + ]; +} diff --git a/subprojects/lix-clang-tidy/meson.build b/subprojects/lix-clang-tidy/meson.build new file mode 100644 index 000000000..ef0226420 --- /dev/null +++ b/subprojects/lix-clang-tidy/meson.build @@ -0,0 +1,18 @@ +project('lix-clang-tidy', ['cpp', 'c'], + version : '0.1', + default_options : ['warning_level=3', 'cpp_std=c++20'] +) + +llvm = dependency('Clang', version: '>= 17', modules: ['libclang']) +sources = files( + 'HasPrefixSuffix.cc', + 'LixClangTidyChecks.cc', + 'FixIncludes.cc', +) + +lix_clang_tidy = shared_module('lix-clang-tidy', sources, + dependencies: llvm, + # overrides build_by_default, see https://github.com/mesonbuild/meson/issues/13498 + install : get_option('build-by-default'), + build_by_default : get_option('build-by-default') +) diff --git a/subprojects/lix-clang-tidy/meson.options b/subprojects/lix-clang-tidy/meson.options new file mode 100644 index 000000000..57f0f713b --- /dev/null +++ b/subprojects/lix-clang-tidy/meson.options @@ -0,0 +1,3 @@ +option('build-by-default', type : 'boolean', value : true, + description : 'set to false to not actually build targets by default. This is a hack to deal with meson lacking a build_by_default default option and building subprojects by default' +) |