[clang-format] Convert AlignEscapedNewlinesLeft to an enum, adding

DontAlign

This converts the clang-format option AlignEscapedNewlinesLeft from a
boolean to an enum, named AlignEscapedNewlines, with options Left (prev.
true), Right (prev. false), and a new option DontAlign.

When set to DontAlign, the backslashes are placed just after the last token in each line:
  #define EXAMPLE \
    do { \
        int x = aaaaa; \
        int b; \
        int dddddddddd; \
    } while (0)

Patch by jtbandes. Thank you!

llvm-svn: 302428

2 files changed, 23 insertions, 7 deletions

diff --git a/clang/lib/Format/Format.cpp b/clang/lib/Format/Format.cpp
index f55a623a8d1..e961e5536ef 100644
--- a/clang/lib/Format/Format.cpp
+++ b/clang/lib/Format/Format.cpp
@@ -171,6 +171,18 @@ template <> struct ScalarEnumerationTraits<FormatStyle::BracketAlignmentStyle> {
   }
 };
 
+template <> struct ScalarEnumerationTraits<FormatStyle::EscapedNewlineAlignmentStyle> {
+  static void enumeration(IO &IO, FormatStyle::EscapedNewlineAlignmentStyle &Value) {
+    IO.enumCase(Value, "DontAlign", FormatStyle::ENAS_DontAlign);
+    IO.enumCase(Value, "Left", FormatStyle::ENAS_Left);
+    IO.enumCase(Value, "Right", FormatStyle::ENAS_Right);
+
+    // For backward compatibility.
+    IO.enumCase(Value, "true", FormatStyle::ENAS_Left);
+    IO.enumCase(Value, "false", FormatStyle::ENAS_Right);
+  }
+};
+
 template <> struct ScalarEnumerationTraits<FormatStyle::PointerAlignmentStyle> {
   static void enumeration(IO &IO, FormatStyle::PointerAlignmentStyle &Value) {
     IO.enumCase(Value, "Middle", FormatStyle::PAS_Middle);
@@ -233,6 +245,7 @@ template <> struct MappingTraits<FormatStyle> {
 
     // For backward compatibility.
     if (!IO.outputting()) {
+      IO.mapOptional("AlignEscapedNewlinesLeft", Style.AlignEscapedNewlines);
       IO.mapOptional("DerivePointerBinding", Style.DerivePointerAlignment);
       IO.mapOptional("IndentFunctionDeclarationAfterType",
                      Style.IndentWrappedFunctionNames);
@@ -247,7 +260,7 @@ template <> struct MappingTraits<FormatStyle> {
                    Style.AlignConsecutiveAssignments);
     IO.mapOptional("AlignConsecutiveDeclarations",
                    Style.AlignConsecutiveDeclarations);
-    IO.mapOptional("AlignEscapedNewlinesLeft", Style.AlignEscapedNewlinesLeft);
+    IO.mapOptional("AlignEscapedNewlines", Style.AlignEscapedNewlines);
     IO.mapOptional("AlignOperands", Style.AlignOperands);
     IO.mapOptional("AlignTrailingComments", Style.AlignTrailingComments);
     IO.mapOptional("AllowAllParametersOfDeclarationOnNextLine",
@@ -498,7 +511,7 @@ FormatStyle getLLVMStyle() {
   FormatStyle LLVMStyle;
   LLVMStyle.Language = FormatStyle::LK_Cpp;
   LLVMStyle.AccessModifierOffset = -2;
-  LLVMStyle.AlignEscapedNewlinesLeft = false;
+  LLVMStyle.AlignEscapedNewlines = FormatStyle::ENAS_Right;
   LLVMStyle.AlignAfterOpenBracket = FormatStyle::BAS_Align;
   LLVMStyle.AlignOperands = true;
   LLVMStyle.AlignTrailingComments = true;
@@ -587,7 +600,7 @@ FormatStyle getGoogleStyle(FormatStyle::LanguageKind Language) {
   GoogleStyle.Language = Language;
 
   GoogleStyle.AccessModifierOffset = -1;
-  GoogleStyle.AlignEscapedNewlinesLeft = true;
+  GoogleStyle.AlignEscapedNewlines = FormatStyle::ENAS_Left;
   GoogleStyle.AllowShortIfStatementsOnASingleLine = true;
   GoogleStyle.AllowShortLoopsOnASingleLine = true;
   GoogleStyle.AlwaysBreakBeforeMultilineStrings = true;
diff --git a/clang/lib/Format/WhitespaceManager.cpp b/clang/lib/Format/WhitespaceManager.cpp
index 2c1f5932497..3b6311d1548 100644
--- a/clang/lib/Format/WhitespaceManager.cpp
+++ b/clang/lib/Format/WhitespaceManager.cpp
@@ -517,8 +517,11 @@ void WhitespaceManager::alignTrailingComments(unsigned Start, unsigned End,
 }
 
 void WhitespaceManager::alignEscapedNewlines() {
-  unsigned MaxEndOfLine =
-      Style.AlignEscapedNewlinesLeft ? 0 : Style.ColumnLimit;
+  if (Style.AlignEscapedNewlines == FormatStyle::ENAS_DontAlign)
+    return;
+
+  bool AlignLeft = Style.AlignEscapedNewlines == FormatStyle::ENAS_Left;
+  unsigned MaxEndOfLine = AlignLeft ? 0 : Style.ColumnLimit;
   unsigned StartOfMacro = 0;
   for (unsigned i = 1, e = Changes.size(); i < e; ++i) {
     Change &C = Changes[i];
@@ -527,7 +530,7 @@ void WhitespaceManager::alignEscapedNewlines() {
         MaxEndOfLine = std::max(C.PreviousEndOfTokenColumn + 2, MaxEndOfLine);
       } else {
         alignEscapedNewlines(StartOfMacro + 1, i, MaxEndOfLine);
-        MaxEndOfLine = Style.AlignEscapedNewlinesLeft ? 0 : Style.ColumnLimit;
+        MaxEndOfLine = AlignLeft ? 0 : Style.ColumnLimit;
         StartOfMacro = i;
       }
     }
@@ -602,7 +605,7 @@ void WhitespaceManager::appendNewlineText(std::string &Text, unsigned Newlines,
                                           unsigned EscapedNewlineColumn) {
   if (Newlines > 0) {
     unsigned Offset =
-        std::min<int>(EscapedNewlineColumn - 1, PreviousEndOfTokenColumn);
+        std::min<int>(EscapedNewlineColumn - 2, PreviousEndOfTokenColumn);
     for (unsigned i = 0; i < Newlines; ++i) {
       Text.append(EscapedNewlineColumn - Offset - 1, ' ');
       Text.append(UseCRLF ? "\\\r\n" : "\\\n");