feedback

Author: hjanuschka

clang-tools-extra/clang-tidy/modernize/UseStartsEndsWithCheck.cpp

@@ -18,6 +18,17 @@
 using namespace clang::ast_matchers;
 
 namespace clang::tidy::modernize {
+
+static bool isNegativeComparison(const Expr *ComparisonExpr) {
+  if (const auto *BO = llvm::dyn_cast<BinaryOperator>(ComparisonExpr))
+    return BO->getOpcode() == BO_NE;
+
+  if (const auto *Op = llvm::dyn_cast<CXXOperatorCallExpr>(ComparisonExpr))
+    return Op->getOperator() == OO_ExclaimEqual;
+
+  return false;
+}
+
 struct NotLengthExprForStringNode {
   NotLengthExprForStringNode(std::string ID, DynTypedNode Node,
                              ASTContext *Context)
@@ -71,17 +82,6 @@ struct NotLengthExprForStringNode {
   ASTContext *Context;
 };
 
-static bool isNegativeComparison(const Expr *ComparisonExpr) {
-  if (const auto *BO = llvm::dyn_cast<BinaryOperator>(ComparisonExpr)) {
-    return BO->getOpcode() == BO_NE;
-  }
-
-  if (const auto *Op = llvm::dyn_cast<CXXOperatorCallExpr>(ComparisonExpr)) {
-    return Op->getOperator() == OO_ExclaimEqual;
-  }
-  return false;
-}
-
 AST_MATCHER_P(Expr, lengthExprForStringNode, std::string, ID) {
   return Builder->removeBindings(NotLengthExprForStringNode(
       ID, DynTypedNode::create(Node), &(Finder->getASTContext())));
@@ -183,6 +183,7 @@ void UseStartsEndsWithCheck::registerMatchers(MatchFinder *Finder) {
           .bind("expr"),
       this);
 
+  // Case 6: X.substr(0, LEN(Y)) [!=]= Y -> ends_with.
   Finder->addMatcher(
       cxxOperatorCallExpr(
           hasAnyOperatorName("==", "!="),
@@ -216,7 +217,7 @@ void UseStartsEndsWithCheck::check(const MatchFinder::MatchResult &Result) {
   if (ComparisonExpr->getBeginLoc().isMacroID())
     return;
 
-  bool Neg = isNegativeComparison(ComparisonExpr);
+  const bool Neg = isNegativeComparison(ComparisonExpr);
 
   // Retrieve the source text of the search expression.
   const auto SearchExprText = Lexer::getSourceText(
@@ -244,9 +245,9 @@ void UseStartsEndsWithCheck::check(const MatchFinder::MatchResult &Result) {
       (SearchExprText + ")").str());
 
   // Add negation if necessary.
-  if (Neg) {
+  if (Neg)
     Diag << FixItHint::CreateInsertion(FindExpr->getBeginLoc(), "!");
-  }
+
 }
 
 } // namespace clang::tidy::modernize

clang-tools-extra/docs/ReleaseNotes.rst

@@ -243,9 +243,9 @@ Changes in existing checks
   ``NULL``/``__null`` (but not ``0``) when used with a templated type.
 
 - Improved :doc:`modernize-use-starts-ends-with
-	  <clang-tidy/checks/modernize/use-starts-ends-with>` check to handle two new
-	  cases from ``rfind`` and ``compare`` to ``ends_with``, and one new case from
-	  ``substr`` to ``starts_with``.
+  <clang-tidy/checks/modernize/use-starts-ends-with>` check to handle two new
+  cases from ``rfind`` and ``compare`` to ``ends_with``, and one new case from
+  ``substr`` to ``starts_with``.
 
 - Improved :doc:`modernize-use-std-format
   <clang-tidy/checks/modernize/use-std-format>` check to support replacing