[clang-tidy] Add fine-grained options to misc-use-internal-linkage

clang-tools-extra/clang-tidy/misc/UseInternalLinkageCheck.cpp

@@ -109,10 +109,22 @@ UseInternalLinkageCheck::UseInternalLinkageCheck(StringRef Name,
                                                  ClangTidyContext *Context)
     : ClangTidyCheck(Name, Context),
       HeaderFileExtensions(Context->getHeaderFileExtensions()),
-      FixMode(Options.get("FixMode", FixModeKind::UseStatic)) {}
+      FixMode(Options.get("FixMode", FixModeKind::UseStatic)),
+      AnalyzeFunctions(Options.get("AnalyzeFunctions", true)),
+      AnalyzeVariables(Options.get("AnalyzeVariables", true)),
+      AnalyzeTypes(Options.get("AnalyzeTypes", true)) {
+  if (!AnalyzeFunctions && !AnalyzeVariables && !AnalyzeTypes)
+    configurationDiag(
+        "the 'misc-use-internal-linkage' check will not perform any "
+        "analysis because its 'AnalyzeFunctions', 'AnalyzeVariables', "
+        "and 'AnalyzeTypes' options have all been set to false");
+}
 
 void UseInternalLinkageCheck::storeOptions(ClangTidyOptions::OptionMap &Opts) {
   Options.store(Opts, "FixMode", FixMode);
+  Options.store(Opts, "AnalyzeFunctions", AnalyzeFunctions);
+  Options.store(Opts, "AnalyzeVariables", AnalyzeVariables);
+  Options.store(Opts, "AnalyzeTypes", AnalyzeTypes);
 }
 
 void UseInternalLinkageCheck::registerMatchers(MatchFinder *Finder) {
@@ -125,24 +137,26 @@ void UseInternalLinkageCheck::registerMatchers(MatchFinder *Finder) {
                                               friendDecl(),
                                               // 3. module export decl
                                               exportDecl()))))));
-  Finder->addMatcher(
-      functionDecl(Common, hasBody(),
-                   unless(anyOf(isExternC(), isStaticStorageClass(),
-                                isExternStorageClass(),
-                                isExplicitTemplateSpecialization(),
-                                cxxMethodDecl(), isConsteval(),
-                                isAllocationOrDeallocationOverloadedFunction(),
-                                isMain())))
-          .bind("fn"),
-      this);
-  Finder->addMatcher(varDecl(Common, hasGlobalStorage(),
-                             unless(anyOf(isExternC(), isStaticStorageClass(),
-                                          isExternStorageClass(),
-                                          isExplicitTemplateSpecialization(),
-                                          hasThreadStorageDuration())))
-                         .bind("var"),
-                     this);
-  if (getLangOpts().CPlusPlus)
+  if (AnalyzeFunctions)
+    Finder->addMatcher(
+        functionDecl(
+            Common, hasBody(),
+            unless(anyOf(
+                isExternC(), isStaticStorageClass(), isExternStorageClass(),
+                isExplicitTemplateSpecialization(), cxxMethodDecl(),
+                isConsteval(), isAllocationOrDeallocationOverloadedFunction(),
+                isMain())))
+            .bind("fn"),
+        this);
+  if (AnalyzeVariables)
+    Finder->addMatcher(varDecl(Common, hasGlobalStorage(),
+                               unless(anyOf(isExternC(), isStaticStorageClass(),
+                                            isExternStorageClass(),
+                                            isExplicitTemplateSpecialization(),
+                                            hasThreadStorageDuration())))
+                           .bind("var"),
+                       this);
+  if (getLangOpts().CPlusPlus && AnalyzeTypes)
     Finder->addMatcher(
         tagDecl(Common, isDefinition(), hasNameForLinkage(),
                 hasDeclContext(anyOf(translationUnitDecl(), namespaceDecl())),

clang-tools-extra/clang-tidy/misc/UseInternalLinkageCheck.h

@@ -36,6 +36,9 @@ class UseInternalLinkageCheck : public ClangTidyCheck {
 private:
   FileExtensionsSet HeaderFileExtensions;
   FixModeKind FixMode;
+  const bool AnalyzeFunctions;
+  const bool AnalyzeVariables;
+  const bool AnalyzeTypes;
 };
 
 } // namespace clang::tidy::misc

clang-tools-extra/docs/ReleaseNotes.rst

@@ -519,7 +519,9 @@ Changes in existing checks
 
 - Improved :doc:`misc-use-internal-linkage
   <clang-tidy/checks/misc/use-internal-linkage>` to suggest giving
-  structs, classes, unions, and enums internal linkage.
+  user-defined types (structs, classes, unions, and enums) internal
+  linkage. Added fine-grained options to control whether the check
+  should diagnose functions, variables, and/or user-defined types.
 
 - Improved :doc:`modernize-avoid-c-arrays
   <clang-tidy/checks/modernize/avoid-c-arrays>` to not diagnose array types

clang-tools-extra/docs/clang-tidy/checks/misc/use-internal-linkage.rst

@@ -17,7 +17,7 @@ Example:
   int v1; // can be marked as static
 
   void fn1() {} // can be marked as static
-  
+
   struct S1 {}; // can be moved into anonymous namespace
 
   namespace {
@@ -50,3 +50,16 @@ Options
 
   - `UseStatic`
     Add ``static`` for internal linkage variable and function.
+
+.. option:: AnalyzeFunctions
+
+  Whether to suggest giving functions internal linkage. Default is `true`.
+
+.. option:: AnalyzeVariables
+
+  Whether to suggest giving variables internal linkage. Default is `true`.
+
+.. option:: AnalyzeTypes
+
+  (C++-only) Whether to suggest giving user-defined types (structs,
+  classes, unions, and enums) internal linkage. Default is `true`.

clang-tools-extra/test/clang-tidy/checkers/misc/use-internal-linkage-func.cpp

@@ -1,6 +1,15 @@
-// RUN: %check_clang_tidy %s misc-use-internal-linkage %t -- -- -I%S/Inputs/use-internal-linkage
 // RUN: %check_clang_tidy %s misc-use-internal-linkage %t -- \
-// RUN:   -config="{CheckOptions: {misc-use-internal-linkage.FixMode: 'UseStatic'}}"  -- -I%S/Inputs/use-internal-linkage
+// RUN:   -config="{CheckOptions: { \
+// RUN:     misc-use-internal-linkage.AnalyzeVariables: false, \
+// RUN:     misc-use-internal-linkage.AnalyzeTypes: false \
+// RUN:   }}" -- -I%S/Inputs/use-internal-linkage
+
+// RUN: %check_clang_tidy %s misc-use-internal-linkage %t -- \
+// RUN:   -config="{CheckOptions: { \
+// RUN:     misc-use-internal-linkage.FixMode: 'UseStatic', \
+// RUN:     misc-use-internal-linkage.AnalyzeVariables: false, \
+// RUN:     misc-use-internal-linkage.AnalyzeTypes: false \
+// RUN:   }}" -- -I%S/Inputs/use-internal-linkage
 
 #include "func.h"
 
@@ -57,7 +66,6 @@ NNDS void func_nnds() {}
 void func_h_inc() {}
 
 struct S {
-// CHECK-MESSAGES: :[[@LINE-1]]:8: warning: struct 'S' can be moved into an anonymous namespace to enforce internal linkage
   void method();
 };
 void S::method() {}
@@ -96,3 +104,6 @@ void * operator new[](std::size_t) { return nullptr; }
 void operator delete(void*) noexcept {}
 void operator delete[](void*) noexcept {}
 // gh117489 end
+
+int ignored_global = 0; // AnalyzeVariables is false.
+struct IgnoredStruct {}; // AnalyzeTypes is false.

clang-tools-extra/test/clang-tidy/checkers/misc/use-internal-linkage-tag.cpp → clang-tools-extra/test/clang-tidy/checkers/misc/use-internal-linkage-type.cpp

@@ -1,8 +1,15 @@
-// RUN: %check_clang_tidy %s misc-use-internal-linkage %t -- -- -I%S/Inputs/use-internal-linkage
 // RUN: %check_clang_tidy %s misc-use-internal-linkage %t -- \
-// RUN:   -config="{CheckOptions: {misc-use-internal-linkage.FixMode: 'UseStatic'}}"  -- -I%S/Inputs/use-internal-linkage
+// RUN:   -config="{CheckOptions: { \
+// RUN:     misc-use-internal-linkage.AnalyzeFunctions: false \
+// RUN:   }}" -- -I%S/Inputs/use-internal-linkage
 
-#include "tag.h"
+// RUN: %check_clang_tidy %s misc-use-internal-linkage %t -- \
+// RUN:   -config="{CheckOptions: { \
+// RUN:     misc-use-internal-linkage.FixMode: 'UseStatic', \
+// RUN:     misc-use-internal-linkage.AnalyzeFunctions: false \
+// RUN:   }}" -- -I%S/Inputs/use-internal-linkage
+
+#include "type.h"
 
 struct StructDeclaredInHeader {};
 union UnionDeclaredInHeader {};
@@ -56,7 +63,6 @@ struct OuterStruct {
 struct OuterStruct::InnerStructDefinedOutOfLine {};
 
 void f() {
-// CHECK-MESSAGES: :[[@LINE-1]]:6: warning: function 'f' can be made static or moved into an anonymous namespace to enforce internal linkage
   struct StructInsideFunction {};
 }
 
@@ -97,3 +103,5 @@ extern "C" {
 struct InExternCBlock { int i; };
 
 }
+
+void ignored_func() {} // AnalyzeFunctions is false.

clang-tools-extra/test/clang-tidy/checkers/misc/use-internal-linkage-var.cpp

@@ -1,6 +1,15 @@
-// RUN: %check_clang_tidy %s misc-use-internal-linkage %t -- -- -I%S/Inputs/use-internal-linkage
 // RUN: %check_clang_tidy %s misc-use-internal-linkage %t -- \
-// RUN:   -config="{CheckOptions: {misc-use-internal-linkage.FixMode: 'UseStatic'}}"  -- -I%S/Inputs/use-internal-linkage
+// RUN:   -config="{CheckOptions: { \
+// RUN:     misc-use-internal-linkage.AnalyzeFunctions: false, \
+// RUN:     misc-use-internal-linkage.AnalyzeTypes: false \
+// RUN:   }}" -- -I%S/Inputs/use-internal-linkage
+
+// RUN: %check_clang_tidy %s misc-use-internal-linkage %t -- \
+// RUN:   -config="{CheckOptions: { \
+// RUN:     misc-use-internal-linkage.FixMode: 'UseStatic', \
+// RUN:     misc-use-internal-linkage.AnalyzeFunctions: false, \
+// RUN:     misc-use-internal-linkage.AnalyzeTypes: false \
+// RUN:   }}" -- -I%S/Inputs/use-internal-linkage
 
 #include "var.h"
 
@@ -47,7 +56,6 @@ static void f(int para) {
 }
 
 struct S {
-// CHECK-MESSAGES: :[[@LINE-1]]:8: warning: struct 'S' can be moved into an anonymous namespace to enforce internal linkage
   int m1;
   static int m2;
 };
@@ -61,3 +69,6 @@ extern "C" int global_in_extern_c_2;
 
 const int const_global = 123;
 constexpr int constexpr_global = 123;
+
+struct IgnoredStruct {}; // AnalyzeTypes is false.
+void ignored_func() {} // AnalyzeFunctions is false.

clang-tools-extra/test/clang-tidy/checkers/misc/use-internal-linkage-wrong-config.cpp

@@ -0,0 +1,8 @@
+// RUN: %check_clang_tidy %s misc-use-internal-linkage %t -- \
+// RUN:   -config="{CheckOptions: { \
+// RUN:     misc-use-internal-linkage.AnalyzeFunctions: false, \
+// RUN:     misc-use-internal-linkage.AnalyzeVariables: false, \
+// RUN:     misc-use-internal-linkage.AnalyzeTypes: false \
+// RUN:   }}"
+
+// CHECK-MESSAGES: warning: the 'misc-use-internal-linkage' check will not perform any analysis because its 'AnalyzeFunctions', 'AnalyzeVariables', and 'AnalyzeTypes' options have all been set to false [clang-tidy-config]