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

tools/gn/scope_unittest.cc

Index: tools/gn/scope_unittest.cc
diff --git a/tools/gn/scope_unittest.cc b/tools/gn/scope_unittest.cc
index a90d725d8dfb4326a0502f55cb8f5d34e133bfe1..534358726ac111caf7860e88a449c3bf18a08ba0 100644
--- a/tools/gn/scope_unittest.cc
+++ b/tools/gn/scope_unittest.cc
@@ -51,7 +51,7 @@ TEST(Scope, NonRecursiveMergeTo) {
 
   // Detect collisions of values' values.
   {
-    Scope new_scope(setup.settings());
+    Scope new_scope(setup.settings(), {});
     Value new_value(&assignment, "goodbye");
     new_scope.SetValue("v", new_value, &assignment);
 
@@ -64,7 +64,7 @@ TEST(Scope, NonRecursiveMergeTo) {
 
   // Template name collisions.
   {
-    Scope new_scope(setup.settings());
+    Scope new_scope(setup.settings(), {});
 
     scoped_refptr<Template> new_templ(
         new Template(&new_scope, &templ_definition));
@@ -78,7 +78,7 @@ TEST(Scope, NonRecursiveMergeTo) {
 
   // The clobber flag should just overwrite colliding values.
   {
-    Scope new_scope(setup.settings());
+    Scope new_scope(setup.settings(), {});
     Value new_value(&assignment, "goodbye");
     new_scope.SetValue("v", new_value, &assignment);
 
@@ -96,7 +96,7 @@ TEST(Scope, NonRecursiveMergeTo) {
 
   // Clobber flag for templates.
   {
-    Scope new_scope(setup.settings());
+    Scope new_scope(setup.settings(), {});
 
     scoped_refptr<Template> new_templ(
         new Template(&new_scope, &templ_definition));
@@ -116,7 +116,7 @@ TEST(Scope, NonRecursiveMergeTo) {
 
   // Don't flag values that technically collide but have the same value.
   {
-    Scope new_scope(setup.settings());
+    Scope new_scope(setup.settings(), {});
     Value new_value(&assignment, "hello");
     new_scope.SetValue("v", new_value, &assignment);
 
@@ -128,7 +128,7 @@ TEST(Scope, NonRecursiveMergeTo) {
 
   // Templates that technically collide but are the same.
   {
-    Scope new_scope(setup.settings());
+    Scope new_scope(setup.settings(), {});
 
     scoped_refptr<Template> new_templ(
         new Template(&new_scope, &templ_definition));
@@ -142,7 +142,7 @@ TEST(Scope, NonRecursiveMergeTo) {
 
   // Copy private values and templates.
   {
-    Scope new_scope(setup.settings());
+    Scope new_scope(setup.settings(), {});
 
     Err err;
     EXPECT_TRUE(setup.scope()->NonRecursiveMergeTo(
@@ -154,7 +154,7 @@ TEST(Scope, NonRecursiveMergeTo) {
 
   // Skip private values and templates.
   {
-    Scope new_scope(setup.settings());
+    Scope new_scope(setup.settings(), {});
 
     Err err;
     Scope::MergeOptions options;
@@ -168,7 +168,7 @@ TEST(Scope, NonRecursiveMergeTo) {
 
   // Don't mark used.
   {
-    Scope new_scope(setup.settings());
+    Scope new_scope(setup.settings(), {});
 
     Err err;
     Scope::MergeOptions options;
@@ -181,7 +181,7 @@ TEST(Scope, NonRecursiveMergeTo) {
 
   // Mark dest used.
   {
-    Scope new_scope(setup.settings());
+    Scope new_scope(setup.settings(), {});
 
     Err err;
     Scope::MergeOptions options;
@@ -192,6 +192,23 @@ TEST(Scope, NonRecursiveMergeTo) {
     EXPECT_TRUE(new_scope.CheckForUnusedVars(&err));
     EXPECT_FALSE(err.has_error());
   }
+
+  // Source file hashes are merged.
+  {
+    Scope gni_scope(setup.settings(), {base::Hash("//features.gni")});
+    Scope new_scope(setup.settings(), {base::Hash("//BUILD.gn")});
+
+    Err err;
+    Scope::MergeOptions options;
+    EXPECT_TRUE(gni_scope.NonRecursiveMergeTo(&new_scope, options, &assignment,
+                                              "error", &err));
+    EXPECT_FALSE(err.has_error());
+    const auto& source_files_hashes = new_scope.source_files_hashes();
+    EXPECT_NE(source_files_hashes.end(),
+              source_files_hashes.find(base::Hash("//features.gni")));
+    EXPECT_NE(source_files_hashes.end(),
+              source_files_hashes.find(base::Hash("//BUILD.gn")));
+  }
 }
 
 TEST(Scope, MakeClosure) {
@@ -207,6 +224,7 @@ TEST(Scope, MakeClosure) {
   assignment.set_value(assignment_token);
   setup.scope()->SetValue("on_root", Value(&assignment, "on_root"),
                            &assignment);
+  setup.scope()->AddSourceFile(SourceFile("//features.gni"));
 
   // Root scope should be const from the nested caller's perspective.
   Scope nested1(static_cast<const Scope*>(setup.scope()));
@@ -228,6 +246,17 @@ TEST(Scope, MakeClosure) {
   EXPECT_TRUE(HasStringValueEqualTo(result.get(), "on_root", "on_root"));
   EXPECT_TRUE(HasStringValueEqualTo(result.get(), "on_one", "on_two"));
   EXPECT_TRUE(HasStringValueEqualTo(result.get(), "on_two", "on_two2"));
+
+  {
+    const auto& source_files_hashes = nested1.source_files_hashes();
+    EXPECT_NE(source_files_hashes.end(),
+              source_files_hashes.find(base::Hash("//features.gni")));
+  }
+  {
+    const auto& source_files_hashes = nested2.source_files_hashes();
+    EXPECT_NE(source_files_hashes.end(),
+              source_files_hashes.find(base::Hash("//features.gni")));
+  }
 }
 
 TEST(Scope, GetMutableValue) {
@@ -248,7 +277,7 @@ TEST(Scope, GetMutableValue) {
   Value value(&assignment, "hello");
 
   // Create a root scope with one value.
-  Scope root_scope(setup.settings());
+  Scope root_scope(setup.settings(), {});
   root_scope.SetValue(kOnConst, value, &assignment);
 
   // Create a first nested scope with a different value.