[clang-format] Don't detect call to ObjC class method as C++11 attribute specifier

Summary:
Previously, clang-format detected something like the following as a C++11 attribute specifier.

  @[[NSArray class]]

instead of an array with an Objective-C method call inside. In general, when the attribute specifier checking runs, if it sees 2 identifiers in a row, it decides that the square brackets represent an Objective-C method call. However, here, `class` is tokenized as a keyword instead of an identifier, so this check fails.

To fix this, the attribute specifier first checks whether the first square bracket has an "@" before it. If it does, then that square bracket is not the start of a attribute specifier because it is an Objective-C array literal. (The assumption is that @[[.*]] is not valid C/C++.)

Contributed by rkgibson2.

Reviewers: benhamilton

Reviewed By: benhamilton

Subscribers: aaron.ballman, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D64632

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@366267 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 5 insertions, 1 deletions

diff --git a/lib/Format/TokenAnnotator.cpp b/lib/Format/TokenAnnotator.cpp
index 6b698e24b5..490c4f4613 100644
--- a/lib/Format/TokenAnnotator.cpp
+++ b/lib/Format/TokenAnnotator.cpp
@@ -388,6 +388,10 @@ private:
   bool isCpp11AttributeSpecifier(const FormatToken &Tok) {
     if (!Style.isCpp() || !Tok.startsSequence(tok::l_square, tok::l_square))
       return false;
+    // The first square bracket is part of an ObjC array literal
+    if (Tok.Previous && Tok.Previous->is(tok::at)) {
+      return false;
+    }
     const FormatToken *AttrTok = Tok.Next->Next;
     if (!AttrTok)
       return false;
@@ -400,7 +404,7 @@ private:
     while (AttrTok && !AttrTok->startsSequence(tok::r_square, tok::r_square)) {
       // ObjC message send. We assume nobody will use : in a C++11 attribute
       // specifier parameter, although this is technically valid:
-      // [[foo(:)]]
+      // [[foo(:)]].
       if (AttrTok->is(tok::colon) ||
           AttrTok->startsSequence(tok::identifier, tok::identifier) ||
           AttrTok->startsSequence(tok::r_paren, tok::identifier))