Add helpers for logging mojom objects.

mojo/public/cpp/bindings/tests/map_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 "mojo/public/cpp/bindings/array.h"
 #include "mojo/public/cpp/bindings/lib/array_serialization.h"
 #include "mojo/public/cpp/bindings/lib/bindings_internal.h"
 #include "mojo/public/cpp/bindings/lib/fixed_buffer.h"
 #include "mojo/public/cpp/bindings/lib/map_serialization.h"
 #include "mojo/public/cpp/bindings/lib/validate_params.h"
@@ skipping 13 matching lines @@
 using mojo::internal::ArrayValidateParams;
 using mojo::internal::FixedBufferForTesting;
 using mojo::internal::Map_Data;
 using mojo::internal::String_Data;
 using mojo::internal::ValidationError;
 
 struct StringIntData {
   const char* string_data;
   int int_data;
 } kStringIntData[] = {
-      {"one", 1},
-      {"two", 2},
-      {"three", 3},
-      {"four", 4},
+    {"one", 1},
+    {"two", 2},
+    {"three", 3},
+    {"four", 4},
 };
 
 const size_t kStringIntDataSize = 4;
 
 class MapTest : public testing::Test {
  public:
   ~MapTest() override {}
 
  private:
   Environment env_;
@@ skipping 378 matching lines @@
   EXPECT_EQ(2u, map2.size());
   EXPECT_FALSE(map2.is_null());
   EXPECT_TRUE(map2[0].is_null());
   EXPECT_FALSE(map2[1].is_null());
   EXPECT_EQ(1, map2[1]->x);
   EXPECT_EQ(2, map2[1]->y);
   EXPECT_EQ(3, map2[1]->width);
   EXPECT_EQ(4, map2[1]->height);
 }
 
+TEST_F(MapTest, OutputFormatting) {
+  Map<int32_t, std::string> null_map;
+  Map<int32_t, std::string> empty_map;
+  empty_map.mark_non_null();
+  Map<int32_t, std::string> one_element_map;
+  one_element_map.insert(123, "abc");
+  Map<int32_t, std::string> three_element_map;
+  three_element_map.insert(4, "d");
+  three_element_map.insert(5, "e");
+  three_element_map.insert(6, "f");
+
+  std::ostringstream so;
+  so << "null_map=" << null_map << ", empty_map=" << empty_map
+     << ", one_element_map=" << one_element_map
+     << ", three_element_map=" << three_element_map;
+
+  EXPECT_EQ(
+      "null_map=null, "
+      "empty_map=[], "
+      "one_element_map=[{123: abc}], "
+      "three_element_map=[{4: d}, {5: e}, {6: f}]",
+      so.str());
+}
+
 }  // namespace
 }  // namespace test
 }  // namespace mojo