[clang-tidy] Fix handling of methods with try-statement as a body in …

…modernize-use-override

Summary:
Fix generated by modernize-use-override caused syntax error when method
used try-statement as a body. `override` keyword was inserted after last
declaration token which happened to be a `try` keyword.

This fixes PR27119.

Reviewers: ehsan, djasper, alexfh

Reviewed By: alexfh

Subscribers: JDevlieghere, cfe-commits

Tags: #clang-tools-extra

Patch by Paweł Żukowski!

Differential Revision: https://reviews.llvm.org/D30002

llvm-svn: 296598

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

@@ -147,14 +147,13 @@ void UseOverrideCheck::check(const MatchFinder::MatchResult &Result) {
       // end of the declaration of the function, but prefer to put it on the
       // same line as the declaration if the beginning brace for the start of
       // the body falls on the next line.
-      Token LastNonCommentToken;
-      for (Token T : Tokens) {
-        if (!T.is(tok::comment)) {
-          LastNonCommentToken = T;
-        }
-      }
-      InsertLoc = LastNonCommentToken.getEndLoc();
       ReplacementText = " override";
+      auto LastTokenIter = std::prev(Tokens.end());
+      // When try statement is used instead of compound statement as
+      // method body - insert override keyword before it.
+      if (LastTokenIter->is(tok::kw_try))
+        LastTokenIter = std::prev(LastTokenIter);
+      InsertLoc = LastTokenIter->getEndLoc();
     }
 
     if (!InsertLoc.isValid()) {

clang-tools-extra/test/clang-tidy/modernize-use-override.cpp

@@ -288,3 +288,17 @@ struct MembersOfSpecializations : public Base2 {
 };
 template <> void MembersOfSpecializations<3>::a() {}
 void ff() { MembersOfSpecializations<3>().a(); };
+
+// In case try statement is used as a method body,
+// make sure that override fix is placed before try keyword.
+struct TryStmtAsBody : public Base {
+  void a() try
+  // CHECK-MESSAGES: :[[@LINE-1]]:8: warning: annotate this
+  // CHECK-FIXES: {{^}}  void a() override try
+  { b(); } catch(...) { c(); }
+
+  virtual void d() try
+  // CHECK-MESSAGES: :[[@LINE-1]]:16: warning: prefer using
+  // CHECK-FIXES: {{^}}  void d() override try
+  { e(); } catch(...) { f(); }
+};