Index: cfe/trunk/lib/Format/UnwrappedLineParser.h
===================================================================
--- cfe/trunk/lib/Format/UnwrappedLineParser.h
+++ cfe/trunk/lib/Format/UnwrappedLineParser.h
@@ -100,7 +100,10 @@
   void parseAccessSpecifier();
   bool parseEnum();
   void parseJavaEnumBody();
-  void parseRecord();
+  // Parses a record (aka class) as a top level element. If ParseAsExpr is true,
+  // parses the record as a child block, i.e. if the class declaration is an
+  // expression.
+  void parseRecord(bool ParseAsExpr = false);
   void parseObjCProtocolList();
   void parseObjCUntilAtEnd();
   void parseObjCInterfaceOrImplementation();
@@ -162,7 +165,7 @@
 
   const FormatStyle &Style;
   const AdditionalKeywords &Keywords;
-  
+
   llvm::Regex CommentPragmasRegex;
 
   FormatTokenSource *Tokens;
Index: cfe/trunk/lib/Format/UnwrappedLineParser.cpp
===================================================================
--- cfe/trunk/lib/Format/UnwrappedLineParser.cpp
+++ cfe/trunk/lib/Format/UnwrappedLineParser.cpp
@@ -1381,6 +1381,12 @@
       if (FormatTok->Tok.is(tok::l_brace))
         parseBracedList();
       break;
+    case tok::kw_class:
+      if (Style.Language == FormatStyle::LK_JavaScript)
+        parseRecord(/*ParseAsExpr=*/true);
+      else
+        nextToken();
+      break;
     case tok::identifier:
       if (Style.Language == FormatStyle::LK_JavaScript &&
           (FormatTok->is(Keywords.kw_function) ||
@@ -1819,7 +1825,7 @@
   addUnwrappedLine();
 }
 
-void UnwrappedLineParser::parseRecord() {
+void UnwrappedLineParser::parseRecord(bool ParseAsExpr) {
   const FormatToken &InitialToken = *FormatTok;
   nextToken();
 
@@ -1863,11 +1869,15 @@
     }
   }
   if (FormatTok->Tok.is(tok::l_brace)) {
-    if (ShouldBreakBeforeBrace(Style, InitialToken))
-      addUnwrappedLine();
+    if (ParseAsExpr) {
+      parseChildBlock();
+    } else {
+      if (ShouldBreakBeforeBrace(Style, InitialToken))
+        addUnwrappedLine();
 
-    parseBlock(/*MustBeDeclaration=*/true, /*AddLevel=*/true,
-               /*MunchSemi=*/false);
+      parseBlock(/*MustBeDeclaration=*/true, /*AddLevel=*/true,
+                 /*MunchSemi=*/false);
+    }
   }
   // There is no addUnwrappedLine() here so that we fall through to parsing a
   // structural element afterwards. Thus, in "class A {} n, m;",
Index: cfe/trunk/unittests/Format/FormatTestJS.cpp
===================================================================
--- cfe/trunk/unittests/Format/FormatTestJS.cpp
+++ cfe/trunk/unittests/Format/FormatTestJS.cpp
@@ -1109,6 +1109,10 @@
   verifyFormat("class C {\n  static x(): string {\n    return 'asd';\n  }\n}");
   verifyFormat("class C extends P implements I {}");
   verifyFormat("class C extends p.P implements i.I {}");
+  verifyFormat(
+      "x(class {\n"
+      "  a(): A {}\n"
+      "});");
   verifyFormat("class Test {\n"
                "  aaaaaaaaaaaaaaaa(aaaaaaaaaaaaaaa: aaaaaaaaaaaaaaaaaaaa):\n"
                "      aaaaaaaaaaaaaaaaaaaaaa {}\n"