[clang-format] Recognize Java logical shift assignment operator

At present, clang-format mangles Java containing logical right shift operators
('>>>=' or '>>>'), splitting them in two, resulting in invalid code:

 public class Minimal {
   public void func(String args) {
     int i = 42;
-    i >>>= 1;
+    i >> >= 1;
     return i;
   }
 }

This adds both forms of logical right shift to the FormatTokenLexer, so
clang-format won't attempt to split them and insert bogus whitespace.

https://reviews.llvm.org/D31652
Patch from Richard Bradfield <bradfier@fstab.me>!

llvm-svn: 299952

1 files changed, 13 insertions, 0 deletions

diff --git a/clang/lib/Format/FormatTokenLexer.cpp b/clang/lib/Format/FormatTokenLexer.cpp
index 9415dbe9ab3..4ee43d6937e 100644
--- a/clang/lib/Format/FormatTokenLexer.cpp
+++ b/clang/lib/Format/FormatTokenLexer.cpp
@@ -84,6 +84,19 @@ void FormatTokenLexer::tryMergePreviousTokens() {
     if (tryMergeTokens(JSRightArrow, TT_JsFatArrow))
       return;
   }
+
+  if (Style.Language == FormatStyle::LK_Java) {
+    static const tok::TokenKind JavaRightLogicalShift[] = {tok::greater,
+                                                           tok::greater,
+                                                           tok::greater};
+    static const tok::TokenKind JavaRightLogicalShiftAssign[] = {tok::greater,
+                                                                 tok::greater,
+                                                                 tok::greaterequal};
+    if (tryMergeTokens(JavaRightLogicalShift, TT_BinaryOperator))
+      return;
+    if (tryMergeTokens(JavaRightLogicalShiftAssign, TT_BinaryOperator))
+      return;
+  }
 }
 
 bool FormatTokenLexer::tryMergeNSStringLiteral() {