clang-format: [JS] for async loops.

Summary:
JavaScript supports asynchronous loop iteration in async functions:

    for async (const x of y) ...

Reviewers: djasper

Subscribers: klimek, cfe-commits

Differential Revision: https://reviews.llvm.org/D33193

llvm-svn: 303106

1 files changed, 10 insertions, 3 deletions

diff --git a/clang/lib/Format/TokenAnnotator.cpp b/clang/lib/Format/TokenAnnotator.cpp
index ad2166cfd3b..387768a6ee5 100644
--- a/clang/lib/Format/TokenAnnotator.cpp
+++ b/clang/lib/Format/TokenAnnotator.cpp
@@ -576,9 +576,12 @@ private:
       }
       break;
     case tok::kw_for:
-      if (Style.Language == FormatStyle::LK_JavaScript && Tok->Previous &&
-          Tok->Previous->is(tok::period))
-        break;
+      if (Style.Language == FormatStyle::LK_JavaScript)
+        if (Tok->Previous && Tok->Previous->is(tok::period))
+          break;
+        // JS' for async ( ...
+        if (CurrentToken->is(Keywords.kw_async))
+          next();
       Contexts.back().ColonIsForRangeExpr = true;
       next();
       if (!parseParens())
@@ -2249,6 +2252,10 @@ bool TokenAnnotator::spaceRequiredBefore(const AnnotatedLine &Line,
   } else if (Style.Language == FormatStyle::LK_JavaScript) {
     if (Left.is(TT_JsFatArrow))
       return true;
+    // for async ( ...
+    if (Right.is(tok::l_paren) && Left.is(Keywords.kw_async) &&
+        Left.Previous && Left.Previous->is(tok::kw_for))
+      return true;
     if (Left.is(Keywords.kw_async) && Right.is(tok::l_paren) &&
         Right.MatchingParen) {
       const FormatToken *Next = Right.MatchingParen->getNextNonComment();