[clang-tidy] Fix handling of out-of-line functions in readability-static-accessed-through-instance

[PiotrZSL]

Summary

Use isStatic instead of isStaticStorageClass to properly
handle a out-of-line definitions.

Fixes: #51861

[Eugene.Zelenko]

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

23

Should be const auto *.

[PiotrZSL]

Fix 'auto'

[carlosgalvezp]

LGTM!

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

 #include "clang/AST/ASTContext.h"
 #include "clang/ASTMatchers/ASTMatchFinder.h"
 #include "llvm/ADT/StringRef.h"
 
 using namespace clang::ast_matchers;
 
 namespace clang::tidy::readability {
 
+namespace {
+AST_MATCHER(CXXMethodDecl, isStatic) { return Node.isStatic(); }
+} // namespace
+
 static unsigned getNameSpecifierNestingLevel(const QualType &QType) {
-  if (const ElaboratedType *ElType = QType->getAs<ElaboratedType>()) {
+  if (const auto *ElType = QType->getAs<ElaboratedType>()) {
     if (const NestedNameSpecifier *NestedSpecifiers = ElType->getQualifier()) {
       unsigned NameSpecifierNestingLevel = 1;
       do {
         NameSpecifierNestingLevel++;
         NestedSpecifiers = NestedSpecifiers->getPrefix();
       } while (NestedSpecifiers);
 
       return NameSpecifierNestingLevel;
     }
   }
   return 0;
 }
 
 void StaticAccessedThroughInstanceCheck::storeOptions(
     ClangTidyOptions::OptionMap &Opts) {
   Options.store(Opts, "NameSpecifierNestingThreshold",
                 NameSpecifierNestingThreshold);
 }
 
 void StaticAccessedThroughInstanceCheck::registerMatchers(MatchFinder *Finder) {
   Finder->addMatcher(
-      memberExpr(hasDeclaration(anyOf(cxxMethodDecl(isStaticStorageClass()),
+      memberExpr(hasDeclaration(anyOf(cxxMethodDecl(isStatic()),
                                       varDecl(hasStaticStorageDuration()),
                                       enumConstantDecl())))
           .bind("memberExpression"),
       this);
 }
 
 void StaticAccessedThroughInstanceCheck::check(
     const MatchFinder::MatchResult &Result) {

clang-tools-extra/docs/ReleaseNotes.rst

- Improved :doc:`readability-identifier-naming
   <clang-tidy/checks/readability/identifier-naming>` check to emit proper
   warnings when a type forward declaration precedes its definition.
 
 - Improved :doc:`readability-implicit-bool-conversion
   <clang-tidy/checks/readability/implicit-bool-conversion>` check to take
   do-while loops into account for the `AllowIntegerConditions` and
   `AllowPointerConditions` options.
 
+- Improved :doc:`readability-static-accessed-through-instance
+  <clang-tidy/checks/readability/static-accessed-through-instance>` check to
+  identify calls to static member functions with out-of-class inline definitions.
+
 Removed checks
 ^^^^^^^^^^^^^^
 
 Improvements to include-fixer
 -----------------------------
 
 The improvements are...
 

clang-tools-extra/test/clang-tidy/checkers/readability/static-accessed-through-instance.cpp

void testEmbeddedAnonymousStructAndClass() {
   // CHECK-MESSAGES: :[[@LINE-1]]:3: warning: static member accessed through instance [readability-static-accessed-through-instance]
   // CHECK-FIXES: {{^}}  llvm_issue_61736::Embedded::EmbeddedClass.f();{{$}}
   E.EmbeddedClassPointer->f();
   // CHECK-MESSAGES: :[[@LINE-1]]:3: warning: static member accessed through instance [readability-static-accessed-through-instance]
   // CHECK-FIXES: {{^}}  llvm_issue_61736::Embedded::EmbeddedClassPointer->f();{{$}}
 }
 
 } // namespace llvm_issue_61736
+
+namespace PR51861 {
+  class Foo {
+    public:
+      static Foo& getInstance();
+      static int getBar();
+  };
+
+  inline int Foo::getBar() { return 42; }
+
+  void test() {
+    auto& params = Foo::getInstance();
+    params.getBar();
+    // CHECK-MESSAGES: :[[@LINE-1]]:5: warning: static member accessed through instance [readability-static-accessed-through-instance]
+    // CHECK-FIXES: {{^}}    PR51861::Foo::getBar();{{$}}
+  }
+}