tools/gn: Convert for loops to use the new range-based loops in C++11.

tools/gn/ninja_build_writer.cc

 // Copyright (c) 2013 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 "tools/gn/ninja_build_writer.h"
 
 #include <fstream>
 #include <map>
 
 #include "base/command_line.h"
@@ skipping 139 matching lines @@
        << "  generator = 1\n"
        << "  depfile = build.ninja.d\n";
 
   // Input build files. These go in the ".d" file. If we write them as
   // dependencies in the .ninja file itself, ninja will expect the files to
   // exist and will error if they don't. When files are listed in a depfile,
   // missing files are ignored.
   dep_out_ << "build.ninja:";
   std::vector<base::FilePath> input_files;
   g_scheduler->input_file_manager()->GetAllPhysicalInputFileNames(&input_files);
-  for (size_t i = 0; i < input_files.size(); i++)
-    dep_out_ << " " << FilePathToUTF8(input_files[i]);
+  for (const auto& input_file : input_files)
+    dep_out_ << " " << FilePathToUTF8(input_file);
 
   // Other files read by the build.
   std::vector<base::FilePath> other_files = g_scheduler->GetGenDependencies();
-  for (size_t i = 0; i < other_files.size(); i++)
-    dep_out_ << " " << FilePathToUTF8(other_files[i]);
+  for (const auto& other_file : other_files)
+    dep_out_ << " " << FilePathToUTF8(other_file);
 
   out_ << std::endl;
 }
 
 void NinjaBuildWriter::WriteLinkPool() {
   out_ << "pool link_pool\n"
        << "  depth = " << default_toolchain_->concurrent_links() << std::endl
        << std::endl;
 }
 
 void NinjaBuildWriter::WriteSubninjas() {
-  for (size_t i = 0; i < all_settings_.size(); i++) {
+  for (const auto& elem : all_settings_) {
     out_ << "subninja ";
-    path_output_.WriteFile(out_, GetNinjaFileForToolchain(all_settings_[i]));
+    path_output_.WriteFile(out_, GetNinjaFileForToolchain(elem));
     out_ << std::endl;
   }
   out_ << std::endl;
 }
 
 bool NinjaBuildWriter::WritePhonyAndAllRules(Err* err) {
   std::string all_rules;
 
   // Write phony rules for all uniquely-named targets in the default toolchain.
   // Don't do other toolchains or we'll get naming conflicts, and if the name
   // isn't unique, also skip it. The exception is for the toplevel targets
   // which we also find.
   std::map<std::string, int> small_name_count;
   std::vector<const Target*> toplevel_targets;
   base::hash_set<std::string> target_files;
-  for (size_t i = 0; i < default_toolchain_targets_.size(); i++) {
-    const Target* target = default_toolchain_targets_[i];
+  for (const auto target : default_toolchain_targets_) {

[scottmg, 2015/03/16 16:20:51]

I don't think this and the one below are correct. Either "const auto&" or
"auto&" when it's necessary to modify the item during the loop.

[tfarina, 2015/03/22 19:59:54]

Done.

     const Label& label = target->label();
     small_name_count[label.name()]++;
 
     // Look for targets with a name of the form
     //   dir = "//foo/", name = "foo"
     // i.e. where the target name matches the top level directory. We will
     // always write phony rules for these even if there is another target with
     // the same short name.
     const std::string& dir_string = label.dir().value();
     if (dir_string.size() == label.name().size() + 3 &&  // Size matches.
         dir_string[0] == '/' && dir_string[1] == '/' &&  // "//" at beginning.
         dir_string[dir_string.size() - 1] == '/' &&  // "/" at end.
         dir_string.compare(2, label.name().size(), label.name()) == 0)
       toplevel_targets.push_back(target);
   }
 
-  for (size_t i = 0; i < default_toolchain_targets_.size(); i++) {
-    const Target* target = default_toolchain_targets_[i];
+  for (const auto target : default_toolchain_targets_) {

[scottmg, 2015/03/16 16:20:51]

here

[tfarina, 2015/03/22 19:59:54]

Done.

     const Label& label = target->label();
     OutputFile target_file(target->dependency_output_file());
     // The output files may have leading "./" so normalize those away.
     NormalizePath(&target_file.value());
     if (!target_files.insert(target_file.value()).second) {
       *err = Err(Location(), "Duplicate rules for " + target_file.value());
       return false;
     }
 
     // Write the long name "foo/bar:baz" for the target "//foo/bar:baz".
@@ skipping 16 matching lines @@
     if (small_name_count[label.name()] == 1)
       WritePhonyRule(target, target_file, label.name());
 
     if (!all_rules.empty())
       all_rules.append(" $\n    ");
     all_rules.append(target_file.value());
   }
 
   // Pick up phony rules for the toplevel targets with non-unique names (which
   // would have been skipped in the above loop).
-  for (size_t i = 0; i < toplevel_targets.size(); i++) {
-    if (small_name_count[toplevel_targets[i]->label().name()] > 1) {
-      const Target* target = toplevel_targets[i];
-      WritePhonyRule(target, target->dependency_output_file(),
-                     target->label().name());
+  for (const auto& toplevel_target : toplevel_targets) {
+    if (small_name_count[toplevel_target->label().name()] > 1) {
+      WritePhonyRule(toplevel_target, toplevel_target->dependency_output_file(),
+                     toplevel_target->label().name());
     }
   }
 
   // Figure out if the BUILD file wants to declare a custom "default"
   // target (rather than building 'all' by default). By convention
   // we use group("default") but it doesn't have to be a group.
   bool default_target_exists = false;
-  for (size_t i = 0; i < default_toolchain_targets_.size(); i++) {
-    const Label& label = default_toolchain_targets_[i]->label();
+  for (const auto target : default_toolchain_targets_) {
+    const Label& label = target->label();
     if (label.dir().value() == "//" && label.name() == "default")
       default_target_exists = true;
   }
 
   if (!all_rules.empty()) {
     out_ << "\nbuild all: phony " << all_rules << std::endl;
   }
 
   if (default_target_exists) {
     out_ << "default default" << std::endl;
@@ skipping 13 matching lines @@
   EscapeOptions ninja_escape;
   ninja_escape.mode = ESCAPE_NINJA;
 
   // Escape for special chars Ninja will handle.
   std::string escaped = EscapeString(phony_name, ninja_escape, nullptr);
 
   out_ << "build " << escaped << ": phony ";
   path_output_.WriteFile(out_, target_file);
   out_ << std::endl;
 }