Implement tracking of BUILD.gn files used to define target, toolchain or

tools/gn/ninja_build_writer_unittest.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 <sstream>
 
 #include "testing/gtest/include/gtest/gtest.h"
 #include "tools/gn/ninja_build_writer.h"
 #include "tools/gn/pool.h"
 #include "tools/gn/scheduler.h"
 #include "tools/gn/target.h"
 #include "tools/gn/test_with_scope.h"
 
 TEST(NinjaBuildWriter, TwoTargets) {
   Scheduler scheduler;
   TestWithScope setup;
   Err err;
 
-  Target target_foo(setup.settings(), Label(SourceDir("//foo/"), "bar"));
+  Target target_foo(setup.settings(), Label(SourceDir("//foo/"), "bar"), {});
   target_foo.set_output_type(Target::ACTION);
   target_foo.action_values().set_script(SourceFile("//foo/script.py"));
   target_foo.action_values().outputs() = SubstitutionList::MakeForTest(
       "//out/Debug/out1.out", "//out/Debug/out2.out");
   target_foo.SetToolchain(setup.toolchain());
   ASSERT_TRUE(target_foo.OnResolved(&err));
 
-  Target target_bar(setup.settings(), Label(SourceDir("//bar/"), "bar"));
+  Target target_bar(setup.settings(), Label(SourceDir("//bar/"), "bar"), {});
   target_bar.set_output_type(Target::ACTION);
   target_bar.action_values().set_script(SourceFile("//bar/script.py"));
   target_bar.action_values().outputs() = SubstitutionList::MakeForTest(
       "//out/Debug/out3.out", "//out/Debug/out4.out");
   target_bar.SetToolchain(setup.toolchain());
   ASSERT_TRUE(target_bar.OnResolved(&err));
 
   // Make a secondary toolchain that references a pool.
   Label other_toolchain_label(SourceDir("//other/"), "toolchain");
-  Pool other_pool(setup.settings(),
-                    Label(SourceDir("//other/"), "pool",
-                          other_toolchain_label.dir(),
-                          other_toolchain_label.name()));
+  Pool other_pool(
+      setup.settings(),
+      Label(SourceDir("//other/"), "pool", other_toolchain_label.dir(),
+            other_toolchain_label.name()),
+      {});
   other_pool.set_depth(42);
-  Toolchain other_toolchain(setup.settings(), other_toolchain_label);
+  Toolchain other_toolchain(setup.settings(), other_toolchain_label, {});
   TestWithScope::SetupToolchain(&other_toolchain);
   other_toolchain.GetTool(Toolchain::TYPE_LINK)->set_pool(
       LabelPtrPair<Pool>(&other_pool));
 
   // Settings to go with the other toolchain.
   Settings other_settings(setup.build_settings(), "toolchain/");
   other_settings.set_toolchain_label(other_toolchain_label);
 
   std::unordered_map<const Settings*, const Toolchain*> used_toolchains;
   used_toolchains[setup.settings()] = setup.toolchain();
@@ skipping 41 matching lines @@
   EXPECT_SNIPPET(expected_root_target);
   EXPECT_SNIPPET(expected_default);
 #undef EXPECT_SNIPPET
 }
 
 TEST(NinjaBuildWriter, DuplicateOutputs) {
   Scheduler scheduler;
   TestWithScope setup;
   Err err;
 
-  Target target_foo(setup.settings(), Label(SourceDir("//foo/"), "bar"));
+  Target target_foo(setup.settings(), Label(SourceDir("//foo/"), "bar"), {});
   target_foo.set_output_type(Target::ACTION);
   target_foo.action_values().set_script(SourceFile("//foo/script.py"));
   target_foo.action_values().outputs() = SubstitutionList::MakeForTest(
       "//out/Debug/out1.out", "//out/Debug/out2.out");
   target_foo.SetToolchain(setup.toolchain());
   ASSERT_TRUE(target_foo.OnResolved(&err));
 
-  Target target_bar(setup.settings(), Label(SourceDir("//bar/"), "bar"));
+  Target target_bar(setup.settings(), Label(SourceDir("//bar/"), "bar"), {});
   target_bar.set_output_type(Target::ACTION);
   target_bar.action_values().set_script(SourceFile("//bar/script.py"));
   target_bar.action_values().outputs() = SubstitutionList::MakeForTest(
       "//out/Debug/out3.out", "//out/Debug/out2.out");
   target_bar.SetToolchain(setup.toolchain());
   ASSERT_TRUE(target_bar.OnResolved(&err));
 
   std::unordered_map<const Settings*, const Toolchain*> used_toolchains;
   used_toolchains[setup.settings()] = setup.toolchain();
   std::vector<const Target*> targets = { &target_foo, &target_bar };
   std::ostringstream ninja_out;
   std::ostringstream depfile_out;
   NinjaBuildWriter writer(setup.build_settings(), used_toolchains,
                           setup.toolchain(), targets, ninja_out, depfile_out);
   ASSERT_FALSE(writer.Run(&err));
 
   const char expected_help_test[] =
       "Two or more targets generate the same output:\n"
       "  out2.out\n"
       "\n"
       "This is can often be fixed by changing one of the target names, or by \n"
       "setting an output_name on one of them.\n"
       "\n"
       "Collisions:\n"
       "  //foo:bar\n"
       "  //bar:bar\n";
 
   EXPECT_EQ(expected_help_test, err.help_text());
 }