[clang-format] [PR43333] Fix C# breaking before function name when using Attributes

Summary:
This is  a fix for https://bugs.llvm.org/show_bug.cgi?id=43333

This comes with 3 main parts

  - C# attributes cause function names on a new line even when AlwaysBreakAfterReturnType is set to None
  - Add AlwaysBreakAfterReturnType  to None by default in the Microsoft style,
  - C# unit tests are not using Microsoft style (which we created to define the default C# style to match a vanilla C# project).

Reviewers: owenpan, klimek, russellmcc, mitchell-stellar

Reviewed By: mitchell-stellar

Subscribers: cfe-commits

Tags: #clang-tools-extra, #clang, #clang-format

Differential Revision: https://reviews.llvm.org/D67629

llvm-svn: 373707

3 files changed, 15 insertions, 4 deletions

diff --git a/clang/lib/Format/ContinuationIndenter.cpp b/clang/lib/Format/ContinuationIndenter.cpp
index 52afb6744ad..2ff6e5ec234 100644
--- a/clang/lib/Format/ContinuationIndenter.cpp
+++ b/clang/lib/Format/ContinuationIndenter.cpp
@@ -473,7 +473,10 @@ bool ContinuationIndenter::mustBreak(const LineState &State) {
   }
 
   // If the return type spans multiple lines, wrap before the function name.
-  if ((Current.is(TT_FunctionDeclarationName) ||
+  if (((Current.is(TT_FunctionDeclarationName) &&
+        // Don't break before a C# function when no break after return type
+        (!Style.isCSharp() ||
+         Style.AlwaysBreakAfterReturnType != FormatStyle::RTBS_None)) ||
        (Current.is(tok::kw_operator) && !Previous.is(tok::coloncolon))) &&
       !Previous.is(tok::kw_template) && State.Stack.back().BreakBeforeParameter)
     return true;
diff --git a/clang/lib/Format/Format.cpp b/clang/lib/Format/Format.cpp
index 5b267784ff1..cd44c0be85f 100644
--- a/clang/lib/Format/Format.cpp
+++ b/clang/lib/Format/Format.cpp
@@ -1084,7 +1084,7 @@ FormatStyle getGNUStyle() {
 }
 
 FormatStyle getMicrosoftStyle(FormatStyle::LanguageKind Language) {
-  FormatStyle Style = getLLVMStyle();
+  FormatStyle Style = getLLVMStyle(Language);
   Style.ColumnLimit = 120;
   Style.TabWidth = 4;
   Style.IndentWidth = 4;
@@ -1105,6 +1105,8 @@ FormatStyle getMicrosoftStyle(FormatStyle::LanguageKind Language) {
   Style.AllowShortCaseLabelsOnASingleLine = false;
   Style.AllowShortIfStatementsOnASingleLine = FormatStyle::SIS_Never;
   Style.AllowShortLoopsOnASingleLine = false;
+  Style.AlwaysBreakAfterDefinitionReturnType = FormatStyle::DRTBS_None;
+  Style.AlwaysBreakAfterReturnType = FormatStyle::RTBS_None;
   return Style;
 }
 
diff --git a/clang/lib/Format/TokenAnnotator.cpp b/clang/lib/Format/TokenAnnotator.cpp
index 91ac9822c8a..319c66c1ead 100644
--- a/clang/lib/Format/TokenAnnotator.cpp
+++ b/clang/lib/Format/TokenAnnotator.cpp
@@ -395,6 +395,12 @@ private:
                          Keywords.kw_internal)) {
       return true;
     }
+
+    // incase its a [XXX] retval func(....
+    if (AttrTok->Next &&
+        AttrTok->Next->startsSequence(tok::identifier, tok::l_paren))
+      return true;
+
     return false;
   }
 
@@ -489,6 +495,8 @@ private:
       } else if (Style.isCpp() && Contexts.back().ContextKind == tok::l_brace &&
                  Parent && Parent->isOneOf(tok::l_brace, tok::comma)) {
         Left->Type = TT_DesignatedInitializerLSquare;
+      } else if (IsCSharp11AttributeSpecifier) {
+        Left->Type = TT_AttributeSquare;
       } else if (CurrentToken->is(tok::r_square) && Parent &&
                  Parent->is(TT_TemplateCloser)) {
         Left->Type = TT_ArraySubscriptLSquare;
@@ -536,8 +544,6 @@ private:
                                  // Should only be relevant to JavaScript:
                                  tok::kw_default)) {
         Left->Type = TT_ArrayInitializerLSquare;
-      } else if (IsCSharp11AttributeSpecifier) {
-        Left->Type = TT_AttributeSquare;
       } else {
         BindingIncrease = 10;
         Left->Type = TT_ArraySubscriptLSquare;