[clang-tidy] Add IgnoredFilesList option to readability-duplicate-include

clang-tools-extra/clang-tidy/readability/DuplicateIncludeCheck.cpp

@@ -7,10 +7,12 @@
 //===----------------------------------------------------------------------===//
 
 #include "DuplicateIncludeCheck.h"
+#include "../utils/OptionsUtils.h"
 #include "clang/Frontend/CompilerInstance.h"
 #include "clang/Lex/Preprocessor.h"
 #include "llvm/ADT/STLExtras.h"
 #include "llvm/ADT/SmallVector.h"
+#include "llvm/Support/Regex.h"
 #include <memory>
 
 namespace clang::tidy::readability {
@@ -33,11 +35,8 @@ using FileList = SmallVector<StringRef>;
 class DuplicateIncludeCallbacks : public PPCallbacks {
 public:
   DuplicateIncludeCallbacks(DuplicateIncludeCheck &Check,
-                            const SourceManager &SM)
-      : Check(Check), SM(SM) {
-    // The main file doesn't participate in the FileChanged notification.
-    Files.emplace_back();
-  }
+                            const SourceManager &SM,
+                            llvm::ArrayRef<StringRef> IgnoredList);
 
   void FileChanged(SourceLocation Loc, FileChangeReason Reason,
                    SrcMgr::CharacteristicKind FileType,
@@ -62,10 +61,31 @@ class DuplicateIncludeCallbacks : public PPCallbacks {
   SmallVector<FileList> Files;
   DuplicateIncludeCheck &Check;
   const SourceManager &SM;
+  SmallVector<llvm::Regex> AllowedRegexes;
 };
 
 } // namespace
 
+DuplicateIncludeCheck::DuplicateIncludeCheck(StringRef Name,
+                                             ClangTidyContext *Context)
+    : ClangTidyCheck(Name, Context),
+      IgnoredFilesList(utils::options::parseStringList(
+          Options.get("IgnoredFilesList", ""))) {}
+
+DuplicateIncludeCallbacks::DuplicateIncludeCallbacks(
+    DuplicateIncludeCheck &Check, const SourceManager &SM,
+    llvm::ArrayRef<StringRef> IgnoredList)
+    : Check(Check), SM(SM) {
+  // The main file doesn't participate in the FileChanged notification.
+  Files.emplace_back();
+
+  AllowedRegexes.reserve(IgnoredList.size());
+  for (const StringRef &It : IgnoredList) {
+    if (!It.empty())
+      AllowedRegexes.emplace_back(It);
+  }
+}
+
 void DuplicateIncludeCallbacks::FileChanged(SourceLocation Loc,
                                             FileChangeReason Reason,
                                             SrcMgr::CharacteristicKind FileType,
@@ -78,14 +98,18 @@ void DuplicateIncludeCallbacks::FileChanged(SourceLocation Loc,
 
 void DuplicateIncludeCallbacks::InclusionDirective(
     SourceLocation HashLoc, const Token &IncludeTok, StringRef FileName,
-    bool IsAngled, CharSourceRange FilenameRange, OptionalFileEntryRef File,
+    bool IsAngled, CharSourceRange FilenameRange, OptionalFileEntryRef /*File*/,
     StringRef SearchPath, StringRef RelativePath, const Module *SuggestedModule,
     bool ModuleImported, SrcMgr::CharacteristicKind FileType) {
   // Skip includes behind macros
   if (FilenameRange.getBegin().isMacroID() ||
       FilenameRange.getEnd().isMacroID())
     return;
   if (llvm::is_contained(Files.back(), FileName)) {
+    if (llvm::any_of(AllowedRegexes, [&FileName](const llvm::Regex &R) {
+          return R.match(FileName);
+        }))
+      return;
     // We want to delete the entire line, so make sure that [Start,End] covers
     // everything.
     const SourceLocation Start =
@@ -111,7 +135,13 @@ void DuplicateIncludeCallbacks::MacroUndefined(const Token &MacroNameTok,
 
 void DuplicateIncludeCheck::registerPPCallbacks(
     const SourceManager &SM, Preprocessor *PP, Preprocessor *ModuleExpanderPP) {
-  PP->addPPCallbacks(std::make_unique<DuplicateIncludeCallbacks>(*this, SM));
+  PP->addPPCallbacks(
+      std::make_unique<DuplicateIncludeCallbacks>(*this, SM, IgnoredFilesList));
+}
+
+void DuplicateIncludeCheck::storeOptions(ClangTidyOptions::OptionMap &Opts) {
+  Options.store(Opts, "IgnoredFilesList",
+                utils::options::serializeStringList(IgnoredFilesList));
 }
 
 } // namespace clang::tidy::readability

clang-tools-extra/clang-tidy/readability/DuplicateIncludeCheck.h

@@ -19,11 +19,16 @@ namespace clang::tidy::readability {
 /// directives between them are analyzed.
 class DuplicateIncludeCheck : public ClangTidyCheck {
 public:
-  DuplicateIncludeCheck(StringRef Name, ClangTidyContext *Context)
-      : ClangTidyCheck(Name, Context) {}
+  DuplicateIncludeCheck(StringRef Name, ClangTidyContext *Context);
 
   void registerPPCallbacks(const SourceManager &SM, Preprocessor *PP,
                            Preprocessor *ModuleExpanderPP) override;
+  void storeOptions(ClangTidyOptions::OptionMap &Opts) override;
+
+private:
+  // Semicolon-separated list of regexes or file names to ignore from duplicate
+  // warnings.
+  const std::vector<StringRef> IgnoredFilesList;
 };
 
 } // namespace clang::tidy::readability

clang-tools-extra/docs/ReleaseNotes.rst

@@ -316,7 +316,7 @@ Changes in existing checks
   exceptions from captures are now diagnosed, exceptions in the bodies of
   lambdas that aren't actually invoked are not. Additionally, fixed an issue
   where the check wouldn't diagnose throws in arguments to functions or
-  constructors. Added fine-grained configuration via options 
+  constructors. Added fine-grained configuration via options
   `CheckDestructors`, `CheckMoveMemberFunctions`, `CheckMain`,
   `CheckedSwapFunctions`, and `CheckNothrowFunctions`.
 
@@ -505,6 +505,11 @@ Changes in existing checks
   ignoring default constructors with user provided arguments and adding
   detection in container's method except ``empty``.
 
+- Improved :doc:`readability-duplicate-include
+  <clang-tidy/checks/readability/duplicate-include>` check by adding
+  the ``IgnoredFilesList`` option (semicolon-separated list of regexes or
+  filenames) to allow intentional duplicates.
+
 - Improved :doc:`readability-identifier-naming
   <clang-tidy/checks/readability/identifier-naming>` check by ignoring
   declarations and macros in system headers. The documentation is also improved

clang-tools-extra/docs/clang-tidy/checks/readability/duplicate-include.rst

@@ -33,3 +33,12 @@ Because of the intervening macro definitions, this code remains unchanged:
   #define NDEBUG
   #include "assertion.h"
   // ...code with assertions disabled
+
+Options
+-------
+
+.. option:: IgnoredFilesList
+
+  A semicolon-separated list of regular expressions or filenames that are
+  allowed to be included multiple times without diagnostics. Matching is
+  performed against the textual include name. Default is an empty string.

clang-tools-extra/test/clang-tidy/checkers/readability/Inputs/duplicate-include/pack_begin.h

@@ -0,0 +1 @@
+// Intentionally unguarded begin-pack header used in tests

clang-tools-extra/test/clang-tidy/checkers/readability/Inputs/duplicate-include/pack_end.h

@@ -0,0 +1 @@
+// Intentionally unguarded end-pack header used in tests

clang-tools-extra/test/clang-tidy/checkers/readability/duplicate-include-ignored-files.cpp

@@ -0,0 +1,24 @@
+// RUN: %check_clang_tidy %s readability-duplicate-include %t -- \
+// RUN:   -config="{CheckOptions: {readability-duplicate-include.IgnoredFilesList: 'pack_.*\\.h'}}" \
+// RUN:   -header-filter='' -- -I %S/Inputs/duplicate-include
+
+int g;
+#include "duplicate-include.h"
+int h;
+#include "duplicate-include.h"
+int i;
+// CHECK-MESSAGES: :[[@LINE-2]]:1: warning: duplicate include [readability-duplicate-include]
+// CHECK-FIXES:      int g;
+// CHECK-FIXES-NEXT: #include "duplicate-include.h"
+// CHECK-FIXES-NEXT: int h;
+// CHECK-FIXES-NEXT: int i;
+
+#include "pack_begin.h"
+struct A { int x; };
+#include "pack_end.h"
+
+#include "pack_begin.h"
+struct B { int x; };
+#include "pack_end.h"
+
+// No warning here.