1 //===--- ElseAfterReturnCheck.cpp - clang-tidy-----------------------------===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 
10 #include "ElseAfterReturnCheck.h"
11 #include "clang/AST/ASTContext.h"
12 #include "clang/ASTMatchers/ASTMatchFinder.h"
13 
14 using namespace clang::ast_matchers;
15 
16 namespace clang {
17 namespace tidy {
18 namespace readability {
19 
20 void ElseAfterReturnCheck::registerMatchers(MatchFinder *Finder) {
21   // FIXME: Support continue, break and throw.
22   Finder->addMatcher(
23       compoundStmt(
24           forEach(ifStmt(hasThen(stmt(anyOf(returnStmt(),
25                                             compoundStmt(has(returnStmt()))))),
26                          hasElse(stmt().bind("else")))
27                       .bind("if"))),
28       this);
29 }
30 
31 static FixItHint removeToken(SourceLocation Loc) {
32   return FixItHint::CreateRemoval(CharSourceRange::getTokenRange(Loc, Loc));
33 }
34 
35 void ElseAfterReturnCheck::check(const MatchFinder::MatchResult &Result) {
36   const auto *If = Result.Nodes.getNodeAs<IfStmt>("if");
37   SourceLocation ElseLoc = If->getElseLoc();
38   DiagnosticBuilder Diag = diag(ElseLoc, "don't use else after return");
39   Diag << removeToken(ElseLoc);
40 
41   // FIXME: Removing the braces isn't always safe. Do a more careful analysis.
42   // FIXME: Change clang-format to correctly un-indent the code.
43   if (const auto *CS = Result.Nodes.getNodeAs<CompoundStmt>("else"))
44     Diag << removeToken(CS->getLBracLoc()) << removeToken(CS->getRBracLoc());
45 }
46 
47 } // namespace readability
48 } // namespace tidy
49 } // namespace clang
50