Redo GN "args" command

tools/gn/value_unittest.cc

+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "testing/gtest/include/gtest/gtest.h"
+#include "tools/gn/value.h"
+
+TEST(Value, ToString) {
+  Value strval(NULL, "hi\" $me\\you\\$\\\"");
+  EXPECT_EQ("hi\" $me\\you\\$\\\"", strval.ToString(false));
+  EXPECT_EQ("\"hi\\\" \\$me\\you\\\\\\$\\\\\\\"\"", strval.ToString(true));
+
+  // Test lists, bools, and ints.
+  Value listval(NULL, Value::LIST);
+  listval.list_value().push_back(Value(NULL, "hi\"me"));
+  listval.list_value().push_back(Value(NULL, true));
+  listval.list_value().push_back(Value(NULL, false));
+  listval.list_value().push_back(Value(NULL, static_cast<int64>(42)));
+  // Printing lists always causes embedded strings to be quoted (ignoring the
+  // quote flag), or else they wouldn't make much sense.
+  EXPECT_EQ("[\"hi\\\"me\", true, false, 42]", listval.ToString(false));
+  EXPECT_EQ("[\"hi\\\"me\", true, false, 42]", listval.ToString(true));
+
+  // Some weird types, we may want to enhance or change printing of these, but
+  // here we test the current behavior.
+  EXPECT_EQ("<void>", Value().ToString(false));
+  EXPECT_EQ("<scope>", Value(NULL, Value::SCOPE).ToString(false));
+}