Index: lib/Format/UnwrappedLineParser.cpp
===================================================================
--- lib/Format/UnwrappedLineParser.cpp
+++ lib/Format/UnwrappedLineParser.cpp
@@ -1259,6 +1259,9 @@
         nextToken();
   }
 
+  if (FormatTok->is(tok::semi))
+    return;
+
   parseChildBlock();
 }
 
Index: unittests/Format/FormatTestJS.cpp
===================================================================
--- unittests/Format/FormatTestJS.cpp
+++ unittests/Format/FormatTestJS.cpp
@@ -377,6 +377,12 @@
       "declare function\n"
       "x();",  // TODO(martinprobst): should ideally be indented.
       NineCols);
+  verifyFormat("declare function foo();\n"
+               "let x = 1;\n");
+  verifyFormat("declare class X {}\n"
+               "let x = 1;\n");
+  verifyFormat("declare interface Y {}\n"
+               "let x = 1;\n");
   verifyFormat(
       "declare enum X {\n"
       "}",