Fixes handling of empty lines in macros.

Now correctly formats:
 #define A \
   \
   b;
to
 #define A b;

Added the state whether an unwrapped line is a macro to the debug
output.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@174878 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Format/Format.cpp b/lib/Format/Format.cpp
index 299a855..a78b650 100644
--- a/lib/Format/Format.cpp
+++ b/lib/Format/Format.cpp
@@ -804,9 +804,10 @@
 
     // Consume and record whitespace until we find a significant token.
     while (FormatTok.Tok.is(tok::unknown)) {
-      FormatTok.NewlinesBefore += Text.count('\n');
-      FormatTok.HasUnescapedNewline =
-          Text.count("\\\n") != FormatTok.NewlinesBefore;
+      unsigned Newlines = Text.count('\n');
+      unsigned EscapedNewlines = Text.count("\\\n");
+      FormatTok.NewlinesBefore += Newlines;
+      FormatTok.HasUnescapedNewline |= EscapedNewlines != Newlines;
       FormatTok.WhiteSpaceLength += FormatTok.Tok.getLength();
 
       if (FormatTok.Tok.is(tok::eof))
diff --git a/lib/Format/UnwrappedLineParser.cpp b/lib/Format/UnwrappedLineParser.cpp
index cb95608..3030789 100644
--- a/lib/Format/UnwrappedLineParser.cpp
+++ b/lib/Format/UnwrappedLineParser.cpp
@@ -766,7 +766,8 @@
   if (Line->Tokens.empty())
     return;
   DEBUG({
-    llvm::dbgs() << "Line(" << Line->Level << "): ";
+    llvm::dbgs() << "Line(" << Line->Level << ")"
+                 << (Line->InPPDirective ? " MACRO" : "") << ": ";
     for (std::list<FormatToken>::iterator I = Line->Tokens.begin(),
                                           E = Line->Tokens.end();
          I != E; ++I) {
diff --git a/unittests/Format/FormatTest.cpp b/unittests/Format/FormatTest.cpp
index 1865b50..83e4fc5 100644
--- a/unittests/Format/FormatTest.cpp
+++ b/unittests/Format/FormatTest.cpp
@@ -858,6 +858,26 @@
   verifyFormat("#define A (1)");
 }
 
+TEST_F(FormatTest, EmptyLinesInMacroDefinitions) {
+  EXPECT_EQ("#define A b;", format("#define A \\\n"
+                                   "          \\\n"
+                                   "  b;", getLLVMStyleWithColumns(25)));
+  EXPECT_EQ("#define A \\\n"
+            "          \\\n"
+            "  a;      \\\n"
+            "  b;", format("#define A \\\n"
+                           "          \\\n"
+                           "  a;      \\\n"
+                           "  b;", getLLVMStyleWithColumns(11)));
+  EXPECT_EQ("#define A \\\n"
+            "  a;      \\\n"
+            "          \\\n"
+            "  b;", format("#define A \\\n"
+                           "  a;      \\\n"
+                           "          \\\n"
+                           "  b;", getLLVMStyleWithColumns(11)));
+}
+
 TEST_F(FormatTest, IndentPreprocessorDirectivesAtZero) {
   EXPECT_EQ("{\n  {\n#define A\n  }\n}", format("{{\n#define A\n}}"));
 }