Improve clang-format's handling of unary operators.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@169500 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 15 insertions, 0 deletions

diff --git a/lib/Format/Format.cpp b/lib/Format/Format.cpp
index 08096866bf..51db69c5ae 100644
--- a/lib/Format/Format.cpp
+++ b/lib/Format/Format.cpp
@@ -618,12 +618,24 @@ private:
 
   bool isUnaryOperator(unsigned Index) {
     const Token &Tok = Line.Tokens[Index].Tok;
+
+    // '++', '--' and '!' are always unary operators.
+    if (Tok.is(tok::minusminus) || Tok.is(tok::plusplus) ||
+        Tok.is(tok::exclaim))
+      return true;
+
+    // The other possible unary operators are '+' and '-' as we
+    // determine the usage of '*' and '&' in determineStarAmpUsage().
     if (Tok.isNot(tok::minus) && Tok.isNot(tok::plus))
       return false;
+
+    // Use heuristics to recognize unary operators.
     const Token &PreviousTok = Line.Tokens[Index - 1].Tok;
     if (PreviousTok.is(tok::equal) || PreviousTok.is(tok::l_paren) ||
         PreviousTok.is(tok::comma) || PreviousTok.is(tok::l_square))
       return true;
+
+    // Fall back to marking the token as binary operator.
     return Annotations[Index - 1].Type == TokenAnnotation::TT_BinaryOperator;
   }
 
diff --git a/unittests/Format/FormatTest.cpp b/unittests/Format/FormatTest.cpp
index 7628b34d4b..a2a37cf1a7 100644
--- a/unittests/Format/FormatTest.cpp
+++ b/unittests/Format/FormatTest.cpp
@@ -364,6 +364,9 @@ TEST_F(FormatTest, UndestandsUnaryOperators) {
   verifyFormat("if (i != -1) {\n}");
   verifyFormat("if (i > -1) {\n}");
   verifyFormat("if (i < -1) {\n}");
+  verifyFormat("++(a->f());");
+  verifyFormat("--(a->f());");
+  verifyFormat("if (!(a->f())) {\n}");
 }
 
 TEST_F(FormatTest, UndestandsOverloadedOperators) {