Refactor GN source expansions.

tools/gn/function_get_target_outputs_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 "testing/gtest/include/gtest/gtest.h"
 #include "tools/gn/functions.h"
 #include "tools/gn/target.h"
 #include "tools/gn/test_with_scope.h"
 
 namespace {
@@ skipping 68 matching lines @@
   Err err;
   Value result = GetTargetOutputs("//foo:bar", &err);
   ASSERT_FALSE(err.has_error());
   AssertSingleStringEquals(result, "//out/Debug/obj/foo/bar.stamp");
 }
 
 TEST_F(GetTargetOutputsTest, Copy) {
   Target* action = new Target(setup_.settings(), GetLabel("//foo/", "bar"));
   action->set_output_type(Target::COPY_FILES);
   action->sources().push_back(SourceFile("//file.txt"));
-  action->action_values().outputs().push_back(
-      "//out/Debug/{{source_file_part}}.one");
+  action->action_values().outputs() =
+      SubstitutionList::MakeForTest("//out/Debug/{{source_file_part}}.one");
 
   items_.push_back(new scoped_ptr<Item>(action));
 
   Err err;
   Value result = GetTargetOutputs("//foo:bar", &err);
   ASSERT_FALSE(err.has_error());
   AssertSingleStringEquals(result, "//out/Debug/file.txt.one");
 }
 
 TEST_F(GetTargetOutputsTest, Action) {
   Target* action = new Target(setup_.settings(), GetLabel("//foo/", "bar"));
   action->set_output_type(Target::ACTION);
-  action->action_values().outputs().push_back("//output1.txt");
-  action->action_values().outputs().push_back("//output2.txt");
+  action->action_values().outputs() = SubstitutionList::MakeForTest(
+      "//output1.txt",
+      "//output2.txt");
 
   items_.push_back(new scoped_ptr<Item>(action));
 
   Err err;
   Value result = GetTargetOutputs("//foo:bar", &err);
   ASSERT_FALSE(err.has_error());
   AssertTwoStringsEqual(result, "//output1.txt", "//output2.txt");
 }
 
 TEST_F(GetTargetOutputsTest, ActionForeach) {
   Target* action = new Target(setup_.settings(), GetLabel("//foo/", "bar"));
   action->set_output_type(Target::ACTION_FOREACH);
   action->sources().push_back(SourceFile("//file.txt"));
-  action->action_values().outputs().push_back(
-      "//out/Debug/{{source_file_part}}.one");
-  action->action_values().outputs().push_back(
+  action->action_values().outputs() = SubstitutionList::MakeForTest(
+      "//out/Debug/{{source_file_part}}.one",
       "//out/Debug/{{source_file_part}}.two");
 
   items_.push_back(new scoped_ptr<Item>(action));
 
   Err err;
   Value result = GetTargetOutputs("//foo:bar", &err);
   ASSERT_FALSE(err.has_error());
   AssertTwoStringsEqual(result, "//out/Debug/file.txt.one",
                         "//out/Debug/file.txt.two");
 }