From ba9ddb66e11bf290e4b3fca9ad0449a5f1a3bbd6 Mon Sep 17 00:00:00 2001
From: Daniel Jasper <djasper@google.com>
Date: Wed, 6 Feb 2013 21:04:05 +0000
Subject: [PATCH] Become a little smarter with formatting long chains of pipes.

Assign a high penalty to breaking before "<<" if the previous token is a
string literal ending in ":" or "=".

Before:
llvm::outs()
    << "aaaaaaaaaaaaaaaaa = " << aaaaaaaaaaaaaaaaa << "bbbbbbbbbbbbbbbbb = "
    << bbbbbbbbbbbbbbbbb << "ccccccccccccccccc = " << ccccccccccccccccc
    << "ddddddddddddddddd = " << ddddddddddddddddd << "eeeeeeeeeeeeeeeee = "
    << eeeeeeeeeeeeeeeee;

After:
llvm::outs() << "aaaaaaaaaaaaaaaaa = " << aaaaaaaaaaaaaaaaa
             << "bbbbbbbbbbbbbbbbb = " << bbbbbbbbbbbbbbbbb
             << "ccccccccccccccccc = " << ccccccccccccccccc
             << "ddddddddddddddddd = " << ddddddddddddddddd
             << "eeeeeeeeeeeeeeeee = " << eeeeeeeeeeeeeeeee;

llvm-svn: 174545
---
 clang/lib/Format/TokenAnnotator.cpp   | 10 +++++++++-
 clang/unittests/Format/FormatTest.cpp |  7 +++++++
 2 files changed, 16 insertions(+), 1 deletion(-)

diff --git a/clang/lib/Format/TokenAnnotator.cpp b/clang/lib/Format/TokenAnnotator.cpp
index 9c7834f..ad3baae 100644
--- a/clang/lib/Format/TokenAnnotator.cpp
+++ b/clang/lib/Format/TokenAnnotator.cpp
@@ -784,8 +784,16 @@ unsigned TokenAnnotator::splitPenalty(const AnnotatedLine &Line,
       Left.Type == TT_TemplateOpener)
     return 20;
 
-  if (Right.is(tok::lessless))
+  if (Right.is(tok::lessless)) {
+    if (Left.is(tok::string_literal)) {
+      char LastChar =
+          StringRef(Left.FormatTok.Tok.getLiteralData(),
+                    Left.FormatTok.TokenLength).drop_back(1).rtrim().back();
+      if (LastChar == ':' || LastChar == '=')
+        return 100;
+    }
     return prec::Shift;
+  }
   if (Left.Type == TT_ConditionalExpr)
     return prec::Assignment;
   prec::Level Level = getPrecedence(Left);
diff --git a/clang/unittests/Format/FormatTest.cpp b/clang/unittests/Format/FormatTest.cpp
index 6909607..160126b 100644
--- a/clang/unittests/Format/FormatTest.cpp
+++ b/clang/unittests/Format/FormatTest.cpp
@@ -1318,6 +1318,13 @@ TEST_F(FormatTest, AlignsPipes) {
                "           << \"  cccccc = \" << pkt.cccccc << \"\\n\"\n"
                "           << \"  ddd = [\" << pkt.ddd << \"]\\n\"\n"
                "           << \"}\";");
+
+  verifyFormat(
+      "llvm::outs() << \"aaaaaaaaaaaaaaaaa = \" << aaaaaaaaaaaaaaaaa\n"
+      "             << \"bbbbbbbbbbbbbbbbb = \" << bbbbbbbbbbbbbbbbb\n"
+      "             << \"ccccccccccccccccc = \" << ccccccccccccccccc\n"
+      "             << \"ddddddddddddddddd = \" << ddddddddddddddddd\n"
+      "             << \"eeeeeeeeeeeeeeeee = \" << eeeeeeeeeeeeeeeee;");
 }
 
 TEST_F(FormatTest, UnderstandsEquals) {
-- 
2.7.4