[clang-format] Annotate do while while

So we can differentiate on the while keyword between a do-while-loop and
a normal while-loop.

Author: HazardyKnusperkeks

clang/lib/Format/FormatToken.h

@@ -67,6 +67,7 @@ namespace format {
   TYPE(DesignatedInitializerLSquare)                                           \
   TYPE(DesignatedInitializerPeriod)                                            \
   TYPE(DictLiteral)                                                            \
+  TYPE(DoWhile)                                                                \
   TYPE(ElseLBrace)                                                             \
   TYPE(ElseRBrace)                                                             \
   TYPE(EnumLBrace)                                                             \

clang/lib/Format/UnwrappedLineParser.cpp

@@ -3137,6 +3137,8 @@ void UnwrappedLineParser::parseDoWhile() {
     return;
   }
 
+  FormatTok->setFinalizedType(TT_DoWhile);
+
   // If in Whitesmiths mode, the line with the while() needs to be indented
   // to the same level as the block.
   if (Style.BreakBeforeBraces == FormatStyle::BS_Whitesmiths)

clang/unittests/Format/TokenAnnotatorTest.cpp

@@ -2334,6 +2334,16 @@ TEST_F(TokenAnnotatorTest, UnderstandsControlStatements) {
   EXPECT_TOKEN(Tokens[5], tok::r_brace, TT_ControlStatementRBrace);
 }
 
+TEST_F(TokenAnnotatorTest, UnderstandsDoWhile) {
+  auto Tokens = annotate("do { ++i; } while ( i > 5 );");
+  ASSERT_EQ(Tokens.size(), 14u) << Tokens;
+  EXPECT_TOKEN(Tokens[6], tok::kw_while, TT_DoWhile);
+
+  Tokens = annotate("do ++i; while ( i > 5 );");
+  ASSERT_EQ(Tokens.size(), 12u) << Tokens;
+  EXPECT_TOKEN(Tokens[4], tok::kw_while, TT_DoWhile);
+}
+
 } // namespace
 } // namespace format
 } // namespace clang