value_cleanup: Rewrite more base::ListValue::Append(base::Value*) calls.

tools/clang/value_cleanup/tests/list-value-append-original.cc

 // Copyright 2016 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 <memory>
 
 #include "base/values.h"
 
 #define true true
 
+base::ListValue* ReturnsRawPtr() {
+  return nullptr;
+}
+
 std::unique_ptr<base::Value> ReturnsUniquePtr() {
   return nullptr;
 }
 
+// The joy of raw pointers.
+void DoesItTakeOwnership(base::Value*) {}
+
 struct Thing {
   std::unique_ptr<base::Value> ToValue() { return nullptr; }
 };
 
 void F() {
   base::ListValue list;
   list.Append(new base::FundamentalValue(1 == 0));
   list.Append(new base::FundamentalValue(true));
   list.Append(new base::FundamentalValue(static_cast<unsigned char>(1.0)));
   list.Append(new base::FundamentalValue(double{3}));
   list.Append(new base::StringValue("abc"));
 
   list.Append(ReturnsUniquePtr().release());
   Thing thing;
   list.Append(thing.ToValue().release());
   std::unique_ptr<base::Value> unique_ptr_var;
   list.Append(unique_ptr_var.release());
 }
+
+void G(base::Value* input) {
+  base::ListValue list;
+
+  base::ListValue* local = new base::ListValue();
+  // Not rewritten, since it often makes more sense to change the function
+  // prototype.
+  local->Append(input);
+  // Should be rewritten: it will only be moved after it's no longer referenced.
+  list.Append(local);
+
+  // Not rewritten, since it would be used after it's moved. In theory, we could
+  // automatically handle this too, but the risk of accidentally breaking
+  // something is much higher.
+  base::ListValue* clever_list = new base::ListValue;
+  list.Append(clever_list);
+  clever_list->AppendInteger(2);
+
+  // Not rewritten, since it often makes more sense to change the function
+  // prototype.
+  base::Value* returned_value = ReturnsRawPtr();
+  list.Append(returned_value);
+
+  // Should be rewritten. The reassignment should be transformed into
+  // .reset().
+  base::ListValue* reused_list = new base::ListValue;
+  reused_list->AppendInteger(1);
+  list.Append(reused_list);
+  reused_list = new base::ListValue;
+  reused_list->AppendInteger(3);
+  list.Append(reused_list);
+
+  // This shouldn't be rewritten, since the reassignment is the return
+  // value of a function.
+  base::ListValue* reused_list_2 = new base::ListValue;
+  reused_list_2->AppendInteger(4);
+  list.Append(reused_list_2);
+  reused_list_2 = ReturnsRawPtr();
+  reused_list_2->AppendInteger(5);
+  list.Append(reused_list_2);
+
+  // auto should be expanded to a std::unique_ptr containing the deduced type.
+  auto* auto_list = new base::ListValue;
+  auto_list->AppendInteger(6);
+  list.Append(auto_list);
+
+  auto auto_list_2 = new base::ListValue;
+  auto_list_2->AppendInteger(7);
+  list.Append(auto_list_2);
+
+  // Shouldn't be rewritten: a raw pointer is passed to a function which may or
+  // may not take ownership.
+  base::ListValue* maybe_owned_list = new base::ListValue;
+  DoesItTakeOwnership(maybe_owned_list);
+  list.Append(maybe_owned_list);
+
+  // Should be rewritten, even though it doesn't have an initializer.
+  base::ListValue* list_with_no_initializer;
+  list_with_no_initializer = new base::ListValue;
+  list.Append(list_with_no_initializer);
+
+  // Make sure C++98 style initialization is correctly handled.
+  base::ListValue* cxx98_list(new base::ListValue);
+  list.Append(cxx98_list);
+
+  // And C++11 style initialization as well.
+  base::ListValue* cxx11_list(new base::ListValue);

[danakj, 2016/06/10 21:59:55]

This is the same as cxx98?

[dcheng, 2016/06/10 22:39:43]

Done.

+  list.Append(cxx11_list);
+}