Retaining path in Observatory.

runtime/vm/service_test.cc

 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "platform/globals.h"
 
 #include "include/dart_debugger_api.h"
 #include "vm/dart_api_impl.h"
 #include "vm/dart_entry.h"
 #include "vm/debugger.h"
@@ skipping 545 matching lines @@
   // Retained by single instance.
   service_msg = Eval(lib,
                      "[port, ['objects', '$validId', 'retained'], [], []]");
   Service::HandleIsolateMessage(isolate, service_msg);
   handler.HandleNextMessage();
   handler.filterMsg("name");
   ExpectSubstringF(handler.msg(),
                    "\"id\":\"objects\\/int-%" Pd "\"",
                    arr.raw()->Size() + arr.At(0)->Size());
 
+  // Retaining path to 'arr', limit 1.
+  service_msg = Eval(
+      lib,
+      "[port, ['objects', '$validId', 'retaining_path'], ['limit'], ['1']]");
+  Service::HandleIsolateMessage(isolate, service_msg);
+  handler.HandleNextMessage();
+  ExpectSubstringF(
+      handler.msg(),
+      "{\"type\":\"RetainingPath\",\"id\":\"retaining_path\",\"length\":1,"
+      "\"elements\":[{\"index\":0,\"value\":{\"type\":\"@Array\"");
+
+  // Retaining path missing limit.
+  service_msg = Eval(
+      lib,
+      "[port, ['objects', '$validId', 'retaining_path'], [], []]");
+  Service::HandleIsolateMessage(isolate, service_msg);
+  handler.HandleNextMessage();
+  ExpectSubstringF(handler.msg(), "{\"type\":\"Error\"");
+
   // eval against list containing an internal object.
   Object& internal_object = Object::Handle();
   internal_object = LiteralToken::New();
   arr.SetAt(0, internal_object);
   service_msg = Eval(lib,
                      "[port, ['objects', '$validId', 'eval'], "
                      "['expr'], ['toString()']]");
   Service::HandleIsolateMessage(isolate, service_msg);
   handler.HandleNextMessage();
   ExpectSubstringF(handler.msg(), "\"type\":\"Error\"");
@@ skipping 843 matching lines @@
   service_msg = Eval(h_lib, "[port, ['profile'], ['tags'], ['hidden']]");
   Service::HandleIsolateMessage(isolate, service_msg);
   handler.HandleNextMessage();
   // Expect error.
   EXPECT_SUBSTRING("\"type\":\"Error\"", handler.msg());
 }
 
 #endif  // !defined(TARGET_ARCH_ARM64)
 
 }  // namespace dart