r204458 - clang-format: Let a trailing comma in braced lists enforce linebreaks.

[Daniel Jasper]

Author: djasper
Date: Fri Mar 21 07:38:57 2014
New Revision: 204458

URL: http://llvm.org/viewvc/llvm-project?rev=204458&view=rev
Log:
clang-format: Let a trailing comma in braced lists enforce linebreaks.

Before:
  vector<int> x{1, 2, 3, 4, };

After:
  vector<int> x{
      1, 2, 3, 4,
  };

This fixes llvm.org/PR18519.

Modified:
    cfe/trunk/lib/Format/TokenAnnotator.cpp
    cfe/trunk/unittests/Format/FormatTest.cpp

Modified: cfe/trunk/lib/Format/TokenAnnotator.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Format/TokenAnnotator.cpp?rev=204458&r1=204457&r2=204458&view=diff
==============================================================================
--- cfe/trunk/lib/Format/TokenAnnotator.cpp (original)
+++ cfe/trunk/lib/Format/TokenAnnotator.cpp Fri Mar 21 07:38:57 2014
@@ -1478,6 +1478,7 @@ bool TokenAnnotator::spaceRequiredBefore
 
 bool TokenAnnotator::mustBreakBefore(const AnnotatedLine &Line,
                                      const FormatToken &Right) {
+  const FormatToken &Left = *Right.Previous;
   if (Right.is(tok::comment)) {
     return Right.Previous->BlockKind != BK_BracedInit &&
            Right.Previous->Type != TT_CtorInitializerColon &&
@@ -1514,6 +1515,13 @@ bool TokenAnnotator::mustBreakBefore(con
              Style.Language == FormatStyle::LK_Proto) {
     // Don't enums onto single lines in protocol buffers.
     return true;
+  } else if ((Left.is(tok::l_brace) && Left.MatchingParen &&
+              Left.MatchingParen->Previous &&
+              Left.MatchingParen->Previous->is(tok::comma)) ||
+             (Right.is(tok::r_brace) && Left.is(tok::comma))) {
+    // If the last token before a '}' is a comma, the intention is to insert a
+    // line break after it in order to make shuffling around entries easier.
+    return true;
   }
   return false;
 }

Modified: cfe/trunk/unittests/Format/FormatTest.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/unittests/Format/FormatTest.cpp?rev=204458&r1=204457&r2=204458&view=diff
==============================================================================
--- cfe/trunk/unittests/Format/FormatTest.cpp (original)
+++ cfe/trunk/unittests/Format/FormatTest.cpp Fri Mar 21 07:38:57 2014
@@ -4901,6 +4901,9 @@ TEST_F(FormatTest, LayoutBraceInitialize
 
 TEST_F(FormatTest, LayoutCxx11ConstructorBraceInitializers) {
   verifyFormat("vector<int> x{1, 2, 3, 4};");
+  verifyFormat("vector<int> x{\n"
+               "    1, 2, 3, 4,\n"
+               "};");
   verifyFormat("vector<T> x{{}, {}, {}, {}};");
   verifyFormat("f({1, 2});");
   verifyFormat("auto v = Foo{-1};");
@@ -5036,8 +5039,9 @@ TEST_F(FormatTest, FormatsBracedListsInC
                getLLVMStyleWithColumns(43));
 
   // Trailing commas.
-  verifyFormat("vector<int> x = {1, 1, 1, 1,\n"
-               "                 1, 1, 1, 1, };",
+  verifyFormat("vector<int> x = {\n"
+               "    1, 1, 1, 1, 1, 1, 1, 1,\n"
+               "};",
                getLLVMStyleWithColumns(39));
   verifyFormat("vector<int> x = {1, 1, 1, 1,\n"
                "                 1, 1, 1, 1, //\n"
@@ -6028,10 +6032,12 @@ TEST_F(FormatTest, ObjCDictLiterals) {
   verifyFormat("@{}");
   verifyFormat("@{@\"one\" : @1}");
   verifyFormat("return @{@\"one\" : @1;");
-  verifyFormat("@{@\"one\" : @1, }");
+  verifyFormat("@{@\"one\" : @1}");
 
   verifyFormat("@{@\"one\" : @{@2 : @1}}");
-  verifyFormat("@{@\"one\" : @{@2 : @1}, }");
+  verifyFormat("@{\n"
+               "  @\"one\" : @{@2 : @1},\n"
+               "}");
 
   verifyFormat("@{1 > 2 ? @\"one\" : @\"two\" : 1 > 2 ? @1 : @2}");
   verifyFormat("[self setDict:@{}");