[clang-tidy] New checker for exceptions that are created but not thrown

Patch by: Kristof Umann

Differential Revision: https://reviews.llvm.org/D43120

llvm-svn: 325222

4 files changed, 92 insertions, 0 deletions

diff --git a/clang-tools-extra/clang-tidy/bugprone/BugproneTidyModule.cpp b/clang-tools-extra/clang-tidy/bugprone/BugproneTidyModule.cpp
index 3b7314298d7..68effd14c88 100644
--- a/clang-tools-extra/clang-tidy/bugprone/BugproneTidyModule.cpp
+++ b/clang-tools-extra/clang-tidy/bugprone/BugproneTidyModule.cpp
@@ -25,6 +25,7 @@
 #include "MultipleStatementMacroCheck.h"
 #include "StringConstructorCheck.h"
 #include "SuspiciousMemsetUsageCheck.h"
+#include "ThrowKeywordMissingCheck.h"
 #include "UndefinedMemoryManipulationCheck.h"
 #include "UseAfterMoveCheck.h"
 #include "VirtualNearMissCheck.h"
@@ -66,6 +67,8 @@ public:
         "bugprone-string-constructor");
     CheckFactories.registerCheck<SuspiciousMemsetUsageCheck>(
         "bugprone-suspicious-memset-usage");
+    CheckFactories.registerCheck<ThrowKeywordMissingCheck>(
+        "bugprone-throw-keyword-missing");
     CheckFactories.registerCheck<UndefinedMemoryManipulationCheck>(
         "bugprone-undefined-memory-manipulation");
     CheckFactories.registerCheck<UseAfterMoveCheck>(
diff --git a/clang-tools-extra/clang-tidy/bugprone/CMakeLists.txt b/clang-tools-extra/clang-tidy/bugprone/CMakeLists.txt
index 11b66c64da3..54d93ef2de1 100644
--- a/clang-tools-extra/clang-tidy/bugprone/CMakeLists.txt
+++ b/clang-tools-extra/clang-tidy/bugprone/CMakeLists.txt
@@ -17,6 +17,7 @@ add_clang_library(clangTidyBugproneModule
   MultipleStatementMacroCheck.cpp
   StringConstructorCheck.cpp
   SuspiciousMemsetUsageCheck.cpp
+  ThrowKeywordMissingCheck.cpp
   UndefinedMemoryManipulationCheck.cpp
   UseAfterMoveCheck.cpp
   VirtualNearMissCheck.cpp
diff --git a/clang-tools-extra/clang-tidy/bugprone/ThrowKeywordMissingCheck.cpp b/clang-tools-extra/clang-tidy/bugprone/ThrowKeywordMissingCheck.cpp
new file mode 100644
index 00000000000..350cf3bc61b
--- /dev/null
+++ b/clang-tools-extra/clang-tidy/bugprone/ThrowKeywordMissingCheck.cpp
@@ -0,0 +1,52 @@
+//===--- ThrowKeywordMissingCheck.cpp - clang-tidy-------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "ThrowKeywordMissingCheck.h"
+#include "clang/AST/ASTContext.h"
+#include "clang/ASTMatchers/ASTMatchFinder.h"
+
+using namespace clang::ast_matchers;
+
+namespace clang {
+namespace tidy {
+namespace bugprone {
+
+void ThrowKeywordMissingCheck::registerMatchers(MatchFinder *Finder) {
+  if (!getLangOpts().CPlusPlus)
+    return;
+
+  auto CtorInitializerList =
+      cxxConstructorDecl(hasAnyConstructorInitializer(anything()));
+
+  Finder->addMatcher(
+      expr(anyOf(cxxFunctionalCastExpr(), cxxBindTemporaryExpr(),
+                 cxxTemporaryObjectExpr()),
+           hasType(cxxRecordDecl(
+               isSameOrDerivedFrom(matchesName("[Ee]xception|EXCEPTION")))),
+           unless(anyOf(hasAncestor(stmt(
+                            anyOf(cxxThrowExpr(), callExpr(), returnStmt()))),
+                        hasAncestor(varDecl()),
+                        allOf(hasAncestor(CtorInitializerList),
+                              unless(hasAncestor(cxxCatchStmt()))))))
+          .bind("temporary-exception-not-thrown"),
+      this); 
+}
+
+void ThrowKeywordMissingCheck::check(const MatchFinder::MatchResult &Result) {
+  const auto *TemporaryExpr =
+      Result.Nodes.getNodeAs<Expr>("temporary-exception-not-thrown");
+
+  diag(TemporaryExpr->getLocStart(), "suspicious exception object created but "
+                                     "not thrown; did you mean 'throw %0'?")
+      << TemporaryExpr->getType().getBaseTypeIdentifier()->getName();
+}
+
+} // namespace bugprone
+} // namespace tidy
+} // namespace clang
diff --git a/clang-tools-extra/clang-tidy/bugprone/ThrowKeywordMissingCheck.h b/clang-tools-extra/clang-tidy/bugprone/ThrowKeywordMissingCheck.h
new file mode 100644
index 00000000000..cc57083c40f
--- /dev/null
+++ b/clang-tools-extra/clang-tidy/bugprone/ThrowKeywordMissingCheck.h
@@ -0,0 +1,36 @@
+//===--- ThrowKeywordMissingCheck.h - clang-tidy-----------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_BUGPRONE_THROWKEYWORDMISSINGCHECK_H
+#define LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_BUGPRONE_THROWKEYWORDMISSINGCHECK_H
+
+#include "../ClangTidy.h"
+
+namespace clang {
+namespace tidy {
+namespace bugprone {
+
+/// Emits a warning about temporary objects whose type is (or is derived from) a
+/// class that has 'EXCEPTION', 'Exception' or 'exception' in its name.
+///
+/// For the user-facing documentation see:
+/// http://clang.llvm.org/extra/clang-tidy/checks/bugprone-throw-keyword-missing.html
+class ThrowKeywordMissingCheck : public ClangTidyCheck {
+public:
+  ThrowKeywordMissingCheck(StringRef Name, ClangTidyContext *Context)
+      : ClangTidyCheck(Name, Context) {}
+  void registerMatchers(ast_matchers::MatchFinder *Finder) override;
+  void check(const ast_matchers::MatchFinder::MatchResult &Result) override;
+};
+
+} // namespace bugprone
+} // namespace tidy
+} // namespace clang
+
+#endif // LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_BUGPRONE_THROWKEYWORDMISSINGCHECK_H