mash: Serialize ShelfIDs for property conversion and transport.

ash/public/cpp/shelf_types.cc

 // Copyright 2017 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 "ash/public/cpp/shelf_types.h"
 
 #include "base/logging.h"
+#include "base/strings/string_split.h"
 
 namespace ash {
 
+namespace {
+
+// A delimiter used to serialize the ShelfID string pair as a single string.
+constexpr char kDelimiter[] = {'|', 0};

[James Cook, 2017/05/15 16:37:23]

const char kDelimiter[] = "|"; doesn't work here? Why the {} initializer?

[msw, 2017/05/15 19:21:31]

Done.

+
+}  // namespace
+
 bool IsValidShelfItemType(int64_t type) {
   return type == TYPE_APP_PANEL || type == TYPE_PINNED_APP ||
          type == TYPE_APP_LIST || type == TYPE_BROWSER_SHORTCUT ||
          type == TYPE_APP || type == TYPE_DIALOG || type == TYPE_UNDEFINED;
 }
 
 ShelfID::ShelfID(const std::string& app_id, const std::string& launch_id)
     : app_id(app_id), launch_id(launch_id) {
   DCHECK(launch_id.empty() || !app_id.empty()) << "launch ids require app ids.";
 }
@@ skipping 16 matching lines @@
 
 bool ShelfID::operator<(const ShelfID& other) const {
   return app_id < other.app_id ||
          (app_id == other.app_id && launch_id < other.launch_id);
 }
 
 bool ShelfID::IsNull() const {
   return app_id.empty() && launch_id.empty();
 }
 
+std::string ShelfID::Serialize() const {
+  DCHECK_EQ(std::string::npos, app_id.find(kDelimiter)) << "Invalid ShelfID";
+  DCHECK_EQ(std::string::npos, launch_id.find(kDelimiter)) << "Invalid ShelfID";
+  return app_id + std::string(kDelimiter) + launch_id;

[James Cook, 2017/05/15 16:37:23]

You might be able to skip the std::string(kDelimiter) here, which might end up
using a slightly-more-efficient template-specialized char* append for
std::string. Not sure, tho, have to see if it compiles.

[msw, 2017/05/15 19:21:31]

Done.

+}
+
+// static
+ShelfID ShelfID::Deserialize(const std::string* string) {
+  if (!string)

[James Cook, 2017/05/15 16:37:23]

Could this be a DCHECK?

[msw, 2017/05/15 19:21:31]

I'd rather not, every kShelfIDKey property read would need special casing for
null values.

+    return ShelfID();
+  std::vector<std::string> components = base::SplitString(
+      *string, kDelimiter, base::KEEP_WHITESPACE, base::SPLIT_WANT_ALL);
+  DCHECK_EQ(2u, components.size()) << "ShelfID serialized incorrectly.";
+  return ShelfID(components[0], components[1]);
+}
+
 }  // namespace ash