Support script response files in GN.

tools/gn/action_target_generator.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/action_target_generator.h"
 
 #include "tools/gn/build_settings.h"
 #include "tools/gn/err.h"
 #include "tools/gn/filesystem_utils.h"
 #include "tools/gn/parse_tree.h"
@@ skipping 30 matching lines @@
 
   if (!FillInputs())
     return;
 
   if (!FillScript())
     return;
 
   if (!FillScriptArgs())
     return;
 
+  if (!FillResponseFileContents())
+    return;
+
   if (!FillOutputs(output_type_ == Target::ACTION_FOREACH))
     return;
 
   if (!FillDepfile())
     return;
 
   if (!FillConsole())
     return;
 
   if (!FillCheckIncludes())
     return;
 
   if (!CheckOutputs())
     return;
 
   // Action outputs don't depend on the current toolchain so we can skip adding
   // that dependency.
+
+  // response_file_contents and {{response_file_name}} in the args must go
+  // together.
+  const auto& required_args_substitutions =
+      target_->action_values().args().required_types();
+  bool has_rsp_file_name = std::find(
+      required_args_substitutions.begin(), required_args_substitutions.end(),
+      SUBSTITUTION_RSP_FILE_NAME) != required_args_substitutions.end();

[scottmg, 2015/11/04 22:35:33]

this is weird formatting, did clang-format do this?

+  if (target_->action_values().uses_rsp_file() && !has_rsp_file_name) {
+    *err_ = Err(function_call_, "Missing {{response_file_name}} in args.",
+        "This target defines response_file_contents but doesn't use\n"
+        "{{response_file_name}} in the args, which means the response file\n"
+        "will be unused.");
+    return;
+  }
+  if (!target_->action_values().uses_rsp_file() && has_rsp_file_name) {
+    *err_ = Err(function_call_, "Missing response_file_content definition.",
+        "This target uses {{response_file_name}} in the args, but does not\n"
+        "define response_file_content which means the response file\n"
+        "will be empty.");
+    return;
+  }
 }
 
 bool ActionTargetGenerator::FillScript() {
   // If this gets called, the target type requires a script, so error out
   // if it doesn't have one.
   const Value* value = scope_->GetValue(variables::kScript, true);
   if (!value) {
     *err_ = Err(function_call_, "This target type requires a \"script\".");
     return false;
   }
@@ skipping 10 matching lines @@
   return true;
 }
 
 bool ActionTargetGenerator::FillScriptArgs() {
   const Value* value = scope_->GetValue(variables::kArgs, true);
   if (!value)
     return true;
   return target_->action_values().args().Parse(*value, err_);
 }
 
+bool ActionTargetGenerator::FillResponseFileContents() {
+  const Value* value = scope_->GetValue(variables::kResponseFileContents, true);
+  if (!value)
+    return true;
+  return target_->action_values().rsp_file_contents().Parse(*value, err_);
+}
+
 bool ActionTargetGenerator::FillDepfile() {
   const Value* value = scope_->GetValue(variables::kDepfile, true);
   if (!value)
     return true;
 
   SubstitutionPattern depfile;
   if (!depfile.Parse(*value, err_))
     return false;
   if (!EnsureSubstitutionIsInOutputDir(depfile, *value))
     return false;
@@ skipping 35 matching lines @@
       *err_ = Err(function_call_,
           "action_foreach should have a pattern in the output.",
           "An action_foreach target should have a source expansion pattern in\n"
           "it to map source file to unique output file name. Otherwise, the\n"
           "build system can't determine when your script needs to be run.");
       return false;
     }
   }
   return true;
 }