clang-format: Make breaking before ternary operators configurable.

llvm-svn: 194229

3 files changed, 30 insertions, 16 deletions

diff --git a/clang/lib/Format/ContinuationIndenter.cpp b/clang/lib/Format/ContinuationIndenter.cpp
index a80e87ddfc8..442f9fa8505 100644
--- a/clang/lib/Format/ContinuationIndenter.cpp
+++ b/clang/lib/Format/ContinuationIndenter.cpp
@@ -125,8 +125,11 @@ bool ContinuationIndenter::mustBreak(const LineState &State) {
   if (Previous.is(tok::semi) && State.LineContainsContinuedForLoopSection)
     return true;
   if ((startsNextParameter(Current, Style) || Previous.is(tok::semi) ||
-       Current.is(tok::question) ||
-       (Current.Type == TT_ConditionalExpr && Previous.isNot(tok::question))) &&
+       (Style.BreakBeforeTernaryOperators &&
+        (Current.is(tok::question) || (Current.Type == TT_ConditionalExpr &&
+                                       Previous.isNot(tok::question)))) ||
+       (!Style.BreakBeforeTernaryOperators &&
+        (Previous.is(tok::question) || Previous.Type == TT_ConditionalExpr))) &&
       State.Stack.back().BreakBeforeParameter && !Current.isTrailingComment() &&
       !Current.isOneOf(tok::r_paren, tok::r_brace))
     return true;
@@ -357,7 +360,9 @@ unsigned ContinuationIndenter::addTokenOnNewLine(LineState &State,
     } else {
       State.Column = State.Stack.back().CallContinuation;
     }
-  } else if (Current.Type == TT_ConditionalExpr) {
+  } else if (State.Stack.back().QuestionColumn != 0 &&
+             (Current.Type == TT_ConditionalExpr ||
+              Previous.Type == TT_ConditionalExpr)) {
     State.Column = State.Stack.back().QuestionColumn;
   } else if (Previous.is(tok::comma) && State.Stack.back().VariablePos != 0) {
     State.Column = State.Stack.back().VariablePos;
@@ -398,14 +403,15 @@ unsigned ContinuationIndenter::addTokenOnNewLine(LineState &State,
       State.Column += Style.ContinuationIndentWidth;
   }
 
-  if (Current.is(tok::question))
-    State.Stack.back().BreakBeforeParameter = true;
   if ((Previous.isOneOf(tok::comma, tok::semi) &&
        !State.Stack.back().AvoidBinPacking) ||
       Previous.Type == TT_BinaryOperator)
     State.Stack.back().BreakBeforeParameter = false;
   if (Previous.Type == TT_TemplateCloser && State.ParenLevel == 0)
     State.Stack.back().BreakBeforeParameter = false;
+  if (Current.is(tok::question) ||
+      (PreviousNonComment && PreviousNonComment->is(tok::question)))
+    State.Stack.back().BreakBeforeParameter = true;
 
   if (!DryRun) {
     unsigned Newlines = 1;
@@ -465,7 +471,10 @@ unsigned ContinuationIndenter::moveStateToNextToken(LineState &State,
   if (Current.Type == TT_ArraySubscriptLSquare &&
       State.Stack.back().StartOfArraySubscripts == 0)
     State.Stack.back().StartOfArraySubscripts = State.Column;
-  if (Current.is(tok::question))
+  if ((Current.is(tok::question) && Style.BreakBeforeTernaryOperators) ||
+      (Current.getPreviousNonComment() && Current.isNot(tok::colon) &&
+       Current.getPreviousNonComment()->is(tok::question) &&
+       !Style.BreakBeforeTernaryOperators))
     State.Stack.back().QuestionColumn = State.Column;
   if (!Current.opensScope() && !Current.closesScope())
     State.LowestLevelOnLine =
diff --git a/clang/lib/Format/Format.cpp b/clang/lib/Format/Format.cpp
index 9443a60aa6d..f2899345fbd 100644
--- a/clang/lib/Format/Format.cpp
+++ b/clang/lib/Format/Format.cpp
@@ -123,6 +123,8 @@ template <> struct MappingTraits<clang::format::FormatStyle> {
                    Style.AlwaysBreakBeforeMultilineStrings);
     IO.mapOptional("BreakBeforeBinaryOperators",
                    Style.BreakBeforeBinaryOperators);
+    IO.mapOptional("BreakBeforeTernaryOperators",
+                   Style.BreakBeforeTernaryOperators);
     IO.mapOptional("BreakConstructorInitializersBeforeComma",
                    Style.BreakConstructorInitializersBeforeComma);
     IO.mapOptional("BinPackParameters", Style.BinPackParameters);
@@ -194,6 +196,7 @@ FormatStyle getLLVMStyle() {
   LLVMStyle.AlwaysBreakTemplateDeclarations = false;
   LLVMStyle.BinPackParameters = true;
   LLVMStyle.BreakBeforeBinaryOperators = false;
+  LLVMStyle.BreakBeforeTernaryOperators = true;
   LLVMStyle.BreakBeforeBraces = FormatStyle::BS_Attach;
   LLVMStyle.BreakConstructorInitializersBeforeComma = false;
   LLVMStyle.ColumnLimit = 80;
@@ -240,6 +243,7 @@ FormatStyle getGoogleStyle() {
   GoogleStyle.AlwaysBreakTemplateDeclarations = true;
   GoogleStyle.BinPackParameters = true;
   GoogleStyle.BreakBeforeBinaryOperators = false;
+  GoogleStyle.BreakBeforeTernaryOperators = true;
   GoogleStyle.BreakBeforeBraces = FormatStyle::BS_Attach;
   GoogleStyle.BreakConstructorInitializersBeforeComma = false;
   GoogleStyle.ColumnLimit = 80;
diff --git a/clang/lib/Format/TokenAnnotator.cpp b/clang/lib/Format/TokenAnnotator.cpp
index 5c70c8f914a..474f6a5adbb 100644
--- a/clang/lib/Format/TokenAnnotator.cpp
+++ b/clang/lib/Format/TokenAnnotator.cpp
@@ -1417,6 +1417,16 @@ bool TokenAnnotator::canBreakBefore(const AnnotatedLine &Line,
   const FormatToken &Left = *Right.Previous;
   if (Right.Type == TT_StartOfName || Right.is(tok::kw_operator))
     return true;
+  if (Right.isTrailingComment())
+    // We rely on MustBreakBefore being set correctly here as we should not
+    // change the "binding" behavior of a comment.
+    return false;
+  if (Left.is(tok::question) && Right.is(tok::colon))
+    return false;
+  if (Right.Type == TT_ConditionalExpr || Right.is(tok::question))
+    return Style.BreakBeforeTernaryOperators;
+  if (Left.Type == TT_ConditionalExpr || Left.is(tok::question))
+    return !Style.BreakBeforeTernaryOperators;
   if (Right.is(tok::colon) &&
       (Right.Type == TT_DictLiteral || Right.Type == TT_ObjCMethodExpr))
     return false;
@@ -1429,10 +1439,6 @@ bool TokenAnnotator::canBreakBefore(const AnnotatedLine &Line,
     return true;
   if (Left.ClosesTemplateDeclaration)
     return true;
-  if ((Right.Type == TT_ConditionalExpr &&
-       !(Right.is(tok::colon) && Left.is(tok::question))) ||
-      Right.is(tok::question))
-    return true;
   if (Right.Type == TT_RangeBasedForLoopColon ||
       Right.Type == TT_OverloadedOperatorLParen ||
       Right.Type == TT_OverloadedOperator)
@@ -1442,8 +1448,7 @@ bool TokenAnnotator::canBreakBefore(const AnnotatedLine &Line,
   if (Right.Type == TT_RangeBasedForLoopColon)
     return false;
   if (Left.Type == TT_PointerOrReference || Left.Type == TT_TemplateCloser ||
-      Left.Type == TT_UnaryOperator || Left.Type == TT_ConditionalExpr ||
-      Left.isOneOf(tok::question, tok::kw_operator))
+      Left.Type == TT_UnaryOperator || Left.is(tok::kw_operator))
     return false;
   if (Left.is(tok::equal) && Line.Type == LT_VirtualFunctionDecl)
     return false;
@@ -1457,10 +1462,6 @@ bool TokenAnnotator::canBreakBefore(const AnnotatedLine &Line,
   }
   if (Right.Type == TT_ImplicitStringLiteral)
     return false;
-  if (Right.isTrailingComment())
-    // We rely on MustBreakBefore being set correctly here as we should not
-    // change the "binding" behavior of a comment.
-    return false;
 
   if (Right.is(tok::r_paren) || Right.Type == TT_TemplateCloser)
     return false;