Fix UseNullptr fails to replace c-style explicit cast in a return statement

This happens whenever there is a c-style explicit cast to nullptr not
surrounded by parentheses following a return statement.

- Added a white space before nullptr if the character before is alphanumeric
  when replacing the null pointer expression.
- Simplified visitor
- Addes tests

llvm-svn: 179103

1 files changed, 12 insertions, 0 deletions

diff --git a/clang-tools-extra/test/cpp11-migrate/UseNullptr/basic.cpp b/clang-tools-extra/test/cpp11-migrate/UseNullptr/basic.cpp
index b7c5d5e3516..e2c63ba6a1a 100644
--- a/clang-tools-extra/test/cpp11-migrate/UseNullptr/basic.cpp
+++ b/clang-tools-extra/test/cpp11-migrate/UseNullptr/basic.cpp
@@ -180,6 +180,18 @@ int test_function_return6() {
   // CHECK: return g_null;
 }
 
+int *test_function_return_cast1() {
+  return(int)0;
+  // CHECK: return nullptr;
+}
+
+int *test_function_return_cast2() {
+  #define RET return
+  RET(int)0;
+  // CHECK: RET nullptr;
+  #undef RET
+}
+
 // Test parentheses expressions resulting in a nullptr.
 int *test_parentheses_expression1() {
   return(0);