clang-format: Add new style option AlignConsecutiveMacros

This option behaves similarly to AlignConsecutiveDeclarations and
AlignConsecutiveAssignments, aligning the assignment of C/C++
preprocessor macros on consecutive lines.

I've worked in many projects (embedded, mostly) where header files full
of large, well-aligned "#define" blocks are a common pattern. We
normally avoid using clang-format on these files, since it ruins any
existing alignment in said blocks. This style option will align "simple"
PP macros (no parameters) and PP macros with parameter lists on
consecutive lines.

Related Bugzilla entry (thanks mcuddie):
https://llvm.org/bugs/show_bug.cgi?id=20637

Patch by Nick Renieris (VelocityRa)!

Differential Revision: https://reviews.llvm.org/D28462

llvm-svn: 364938

1 files changed, 2 insertions, 0 deletions

diff --git a/clang/lib/Format/Format.cpp b/clang/lib/Format/Format.cpp
index 31442b5124d..c48182976b0 100644
--- a/clang/lib/Format/Format.cpp
+++ b/clang/lib/Format/Format.cpp
@@ -341,6 +341,7 @@ template <> struct MappingTraits<FormatStyle> {
 
     IO.mapOptional("AccessModifierOffset", Style.AccessModifierOffset);
     IO.mapOptional("AlignAfterOpenBracket", Style.AlignAfterOpenBracket);
+    IO.mapOptional("AlignConsecutiveMacros", Style.AlignConsecutiveMacros);
     IO.mapOptional("AlignConsecutiveAssignments",
                    Style.AlignConsecutiveAssignments);
     IO.mapOptional("AlignConsecutiveDeclarations",
@@ -666,6 +667,7 @@ FormatStyle getLLVMStyle(FormatStyle::LanguageKind Language) {
   LLVMStyle.AlignTrailingComments = true;
   LLVMStyle.AlignConsecutiveAssignments = false;
   LLVMStyle.AlignConsecutiveDeclarations = false;
+  LLVMStyle.AlignConsecutiveMacros = false;
   LLVMStyle.AllowAllArgumentsOnNextLine = true;
   LLVMStyle.AllowAllConstructorInitializersOnNextLine = true;
   LLVMStyle.AllowAllParametersOfDeclarationOnNextLine = true;