Index: lib/Format/TokenAnnotator.cpp
===================================================================
--- lib/Format/TokenAnnotator.cpp
+++ lib/Format/TokenAnnotator.cpp
@@ -1570,7 +1570,7 @@
       const FormatToken *NextNonComment = Current->getNextNonComment();
       if (Current->is(TT_ConditionalExpr))
         return prec::Conditional;
-      if (NextNonComment && NextNonComment->is(tok::colon) &&
+      if (NextNonComment && Current->is(TT_SelectorName) &&
           NextNonComment->is(TT_DictLiteral))
         return prec::Assignment;
       if (Current->is(TT_JsComputedPropertyName))
Index: unittests/Format/FormatTestProto.cpp
===================================================================
--- unittests/Format/FormatTestProto.cpp
+++ unittests/Format/FormatTestProto.cpp
@@ -201,6 +201,12 @@
                "  field_c: \"OK\"\n"
                "  msg_field{field_d: 123}\n"
                "};");
+  verifyFormat("option (MyProto.options) = {\n"
+               "  field_a: OK\n"
+               "  field_b{field_c: OK}\n"
+               "  field_d: OKOKOK\n"
+               "  field_e: OK\n"
+               "}");
 
   // Support syntax with <> instead of {}.
   verifyFormat("option (MyProto.options) = {\n"