clang-format: add options to merge empty record body

Summary:
This patch introduces a few extra BraceWrapping options, similar to
`SplitEmptyFunction`, to allow merging empty 'record' bodies (e.g.
class, struct, union and namespace):
* SplitEmptyClass
* SplitEmptyStruct
* SplitEmptyUnion
* SplitEmptyNamespace

The `SplitEmptyFunction` option name has also been simplified/
shortened (from `SplitEmptyFunctionBody`).

These options are helpful when the correspond AfterXXX option is
enabled, to allow merging the empty record:

  class Foo
  {};

In addition, this fixes an unexpected merging of short records, when
the AfterXXXX options are used, which caused to be formatted like
this:

  class Foo
  { void Foo(); };

This is now properly formatted as:

  class Foo
  {
     void Foo();
  };

Reviewers: djasper, krasimir

Reviewed By: djasper

Subscribers: cfe-commits, klimek

Differential Revision: https://reviews.llvm.org/D34395

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@306874 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 23 insertions, 1 deletions

diff --git a/include/clang/Format/Format.h b/include/clang/Format/Format.h
index 5b587a4db0..ee24c55fef 100644
--- a/include/clang/Format/Format.h
+++ b/include/clang/Format/Format.h
@@ -717,7 +717,29 @@ struct FormatStyle {
     ///                   }
     /// \endcode
     ///
-    bool SplitEmptyFunctionBody;
+    bool SplitEmptyFunction;
+    /// \brief If ``false``, empty record (e.g. class, struct or union) body
+    /// can be put on a single line. This option is used only if the opening
+    /// brace of the record has already been wrapped, i.e. the `AfterClass`
+    /// (for classes) brace wrapping mode is set.
+    /// \code
+    ///   class Foo   vs.  class Foo
+    ///   {}               {
+    ///                    }
+    /// \endcode
+    ///
+    bool SplitEmptyRecord;
+    /// \brief If ``false``, empty namespace body can be put on a single line.
+    /// This option is used only if the opening brace of the namespace has
+    /// already been wrapped, i.e. the `AfterNamespace` brace wrapping mode is
+    /// set.
+    /// \code
+    ///   namespace Foo   vs.  namespace Foo
+    ///   {}                   {
+    ///                        }
+    /// \endcode
+    ///
+    bool SplitEmptyNamespace;
   };
 
   /// \brief Control of individual brace wrapping cases.