Only break string literals as a last resort.

We might want to move towards doing this if the formatting can be
significantly improved, but we need to carefully evaluate the different
situations first.

Before (the string literal was split by clang-format here):
aaaaaaaaaaaaaaaaaaaa(aaaaaaaaaaaaaaaaaaaa, aaaaaa("aaa aaaaa aaa aaa aaaaa aaa "
                                                  "aaaaa aaa aaa aaaaaa"));

After:
aaaaaaaaaaaaaaaaaaaa(
    aaaaaaaaaaaaaaaaaaaa,
    aaaaaa("aaa aaaaa aaa aaa aaaaa aaa aaaaa aaa aaa aaaaaa"));

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@176084 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 7 insertions, 1 deletions

diff --git a/lib/Format/Format.cpp b/lib/Format/Format.cpp
index 00ec79f5e4..7687aa347b 100644
--- a/lib/Format/Format.cpp
+++ b/lib/Format/Format.cpp
@@ -727,7 +727,7 @@ private:
       TailOffset += SplitPoint + 1;
       TailLength -= SplitPoint + 1;
       OffsetFromStart = 1;
-      Penalty += 100;
+      Penalty += Style.PenaltyExcessCharacter;
     }
     State.Column = StartColumn + TailLength;
     return Penalty;
diff --git a/unittests/Format/FormatTest.cpp b/unittests/Format/FormatTest.cpp
index 17dae0ffe6..a902466c4c 100644
--- a/unittests/Format/FormatTest.cpp
+++ b/unittests/Format/FormatTest.cpp
@@ -2984,6 +2984,12 @@ TEST_F(FormatTest, BreakStringLiterals) {
             "  \"text\",\n"
             "  other);",
             format("f(\"some text\", other);", getLLVMStyleWithColumns(10)));
+
+  // Only break as a last resort.
+  verifyFormat(
+      "aaaaaaaaaaaaaaaaaaaa(\n"
+      "    aaaaaaaaaaaaaaaaaaaa,\n"
+      "    aaaaaa(\"aaa aaaaa aaa aaa aaaaa aaa aaaaa aaa aaa aaaaaa\"));");
 }
 
 } // end namespace tooling