From 1fcbe675faf60f0ace39c879e423f17bae4e2947 Mon Sep 17 00:00:00 2001
From: Manuel Klimek <klimek@google.com>
Date: Fri, 11 Apr 2014 12:27:47 +0000
Subject: [PATCH] Correctly handle escaped newlines when the next token starts
 without a space.

We will need this to correctly handle conflict markers inside macro
definitions.

llvm-svn: 206029
---
 clang/lib/Format/Format.cpp              |  4 +++-
 clang/lib/Format/TokenAnnotator.cpp      |  2 +-
 clang/lib/Format/UnwrappedLineParser.cpp | 13 +++++++++----
 clang/lib/Format/UnwrappedLineParser.h   |  1 +
 4 files changed, 14 insertions(+), 6 deletions(-)

diff --git a/clang/lib/Format/Format.cpp b/clang/lib/Format/Format.cpp
index 4075ccdc8cfd..95ae7b56dc41 100644
--- a/clang/lib/Format/Format.cpp
+++ b/clang/lib/Format/Format.cpp
@@ -913,6 +913,8 @@ private:
       Newlines = std::min(Newlines, 1u);
     if (Newlines == 0 && !RootToken.IsFirst)
       Newlines = 1;
+    if (RootToken.IsFirst && !RootToken.HasUnescapedNewline)
+      Newlines = 0;
 
     // Remove empty lines after "{".
     if (!Style.KeepEmptyLinesAtTheStartOfBlocks && PreviousLine &&
@@ -1329,7 +1331,7 @@ private:
     // FIXME: Add a more explicit test.
     while (FormatTok->TokenText.size() > 1 && FormatTok->TokenText[0] == '\\' &&
            FormatTok->TokenText[1] == '\n') {
-      // FIXME: ++FormatTok->NewlinesBefore is missing...
+      ++FormatTok->NewlinesBefore;
       WhitespaceLength += 2;
       Column = 0;
       FormatTok->TokenText = FormatTok->TokenText.substr(2);
diff --git a/clang/lib/Format/TokenAnnotator.cpp b/clang/lib/Format/TokenAnnotator.cpp
index df5603b26825..174a7fa20228 100644
--- a/clang/lib/Format/TokenAnnotator.cpp
+++ b/clang/lib/Format/TokenAnnotator.cpp
@@ -1511,7 +1511,7 @@ bool TokenAnnotator::mustBreakBefore(const AnnotatedLine &Line,
   if (Right.is(tok::comment)) {
     return Right.Previous->BlockKind != BK_BracedInit &&
            Right.Previous->Type != TT_CtorInitializerColon &&
-           Right.NewlinesBefore > 0;
+           (Right.NewlinesBefore > 0 && Right.HasUnescapedNewline);
   } else if (Right.Previous->isTrailingComment() ||
              (Right.isStringLiteral() && Right.Previous->isStringLiteral())) {
     return true;
diff --git a/clang/lib/Format/UnwrappedLineParser.cpp b/clang/lib/Format/UnwrappedLineParser.cpp
index 8d951bb8c627..004c83648309 100644
--- a/clang/lib/Format/UnwrappedLineParser.cpp
+++ b/clang/lib/Format/UnwrappedLineParser.cpp
@@ -1358,13 +1358,18 @@ void UnwrappedLineParser::addUnwrappedLine() {
 
 bool UnwrappedLineParser::eof() const { return FormatTok->Tok.is(tok::eof); }
 
+bool UnwrappedLineParser::isOnNewLine(const FormatToken& FormatTok) {
+  return (Line->InPPDirective || FormatTok.HasUnescapedNewline) &&
+         FormatTok.NewlinesBefore > 0;
+}
+
 void UnwrappedLineParser::flushComments(bool NewlineBeforeNext) {
   bool JustComments = Line->Tokens.empty();
   for (SmallVectorImpl<FormatToken *>::const_iterator
            I = CommentsBeforeNextToken.begin(),
            E = CommentsBeforeNextToken.end();
        I != E; ++I) {
-    if ((*I)->NewlinesBefore && JustComments) {
+    if (isOnNewLine(**I) && JustComments) {
       addUnwrappedLine();
     }
     pushToken(*I);
@@ -1378,7 +1383,7 @@ void UnwrappedLineParser::flushComments(bool NewlineBeforeNext) {
 void UnwrappedLineParser::nextToken() {
   if (eof())
     return;
-  flushComments(FormatTok->NewlinesBefore > 0);
+  flushComments(isOnNewLine(*FormatTok));
   pushToken(FormatTok);
   readToken();
 }
@@ -1398,7 +1403,7 @@ void UnwrappedLineParser::readToken() {
       // Comments stored before the preprocessor directive need to be output
       // before the preprocessor directive, at the same level as the
       // preprocessor directive, as we consider them to apply to the directive.
-      flushComments(FormatTok->NewlinesBefore > 0);
+      flushComments(isOnNewLine(*FormatTok));
       parsePPDirective();
     }
 
@@ -1409,7 +1414,7 @@ void UnwrappedLineParser::readToken() {
 
     if (!FormatTok->Tok.is(tok::comment))
       return;
-    if (FormatTok->NewlinesBefore > 0 || FormatTok->IsFirst) {
+    if (isOnNewLine(*FormatTok) || FormatTok->IsFirst) {
       CommentsInCurrentLine = false;
     }
     if (CommentsInCurrentLine) {
diff --git a/clang/lib/Format/UnwrappedLineParser.h b/clang/lib/Format/UnwrappedLineParser.h
index 62e0b58ea13b..6eaa415b6b81 100644
--- a/clang/lib/Format/UnwrappedLineParser.h
+++ b/clang/lib/Format/UnwrappedLineParser.h
@@ -108,6 +108,7 @@ private:
   void pushToken(FormatToken *Tok);
   void calculateBraceTypes();
   void pushPPConditional();
+  bool isOnNewLine(const FormatToken& FormatTok);
 
   // FIXME: We are constantly running into bugs where Line.Level is incorrectly
   // subtracted from beyond 0. Introduce a method to subtract from Line.Level