14 files changed, 594 insertions, 108 deletions

diff --git a/tools/aapt2/cmd/Compile.cpp b/tools/aapt2/cmd/Compile.cpp
index 21719705838d..32686538c10d 100644
--- a/tools/aapt2/cmd/Compile.cpp
+++ b/tools/aapt2/cmd/Compile.cpp
@@ -630,6 +630,12 @@ class CompileContext : public IAaptContext {
     return 0;
   }
 
+  const std::set<std::string>& GetSplitNameDependencies() override {
+    UNIMPLEMENTED(FATAL) << "No Split Name Dependencies be needed in compile phase";
+    static std::set<std::string> empty;
+    return empty;
+  }
+
  private:
   DISALLOW_COPY_AND_ASSIGN(CompileContext);
 
@@ -735,7 +741,6 @@ int CompileCommand::Action(const std::vector<std::string>& args) {
   }
 
   std::unique_ptr<io::IFileCollection> file_collection;
-  std::unique_ptr<IArchiveWriter> archive_writer;
 
   // Collect the resources files to compile
   if (options_.res_dir && options_.res_zip) {
@@ -756,8 +761,6 @@ int CompileCommand::Action(const std::vector<std::string>& args) {
       context.GetDiagnostics()->Error(DiagMessage(options_.res_dir.value()) << err);
       return 1;
     }
-
-    archive_writer = CreateZipFileArchiveWriter(context.GetDiagnostics(), options_.output_path);
   } else if (options_.res_zip) {
     if (!args.empty()) {
       context.GetDiagnostics()->Error(DiagMessage() << "files given but --zip specified");
@@ -772,8 +775,6 @@ int CompileCommand::Action(const std::vector<std::string>& args) {
       context.GetDiagnostics()->Error(DiagMessage(options_.res_zip.value()) << err);
       return 1;
     }
-
-    archive_writer = CreateZipFileArchiveWriter(context.GetDiagnostics(), options_.output_path);
   } else {
     auto collection = util::make_unique<io::FileCollection>();
 
@@ -786,7 +787,14 @@ int CompileCommand::Action(const std::vector<std::string>& args) {
     }
 
     file_collection = std::move(collection);
+  }
+
+  std::unique_ptr<IArchiveWriter> archive_writer;
+  file::FileType output_file_type = file::GetFileType(options_.output_path);
+  if (output_file_type == file::FileType::kDirectory) {
     archive_writer = CreateDirectoryArchiveWriter(context.GetDiagnostics(), options_.output_path);
+  } else {
+    archive_writer = CreateZipFileArchiveWriter(context.GetDiagnostics(), options_.output_path);
   }
 
   if (!archive_writer) {
diff --git a/tools/aapt2/cmd/Compile_test.cpp b/tools/aapt2/cmd/Compile_test.cpp
index 5f637bd8d582..fb786a31360e 100644
--- a/tools/aapt2/cmd/Compile_test.cpp
+++ b/tools/aapt2/cmd/Compile_test.cpp
@@ -200,7 +200,7 @@ static void AssertTranslations(CommandTestFixture *ctf, std::string file_name,
   const std::string compiled_files_dir = ctf->GetTestPath("/compiled_" + file_name);
   const std::string out_apk = ctf->GetTestPath("/" + file_name + ".apk");
 
-  CHECK(ctf->WriteFile(source_file, sTranslatableXmlContent));
+  ctf->WriteFile(source_file, sTranslatableXmlContent);
   CHECK(file::mkdirs(compiled_files_dir.data()));
 
   ASSERT_EQ(CompileCommand(&diag).Execute({
diff --git a/tools/aapt2/cmd/Convert.cpp b/tools/aapt2/cmd/Convert.cpp
index 0cf86ccdd59f..22bcd8589ce9 100644
--- a/tools/aapt2/cmd/Convert.cpp
+++ b/tools/aapt2/cmd/Convert.cpp
@@ -243,6 +243,12 @@ class Context : public IAaptContext {
     return 0u;
   }
 
+  const std::set<std::string>& GetSplitNameDependencies() override {
+    UNIMPLEMENTED(FATAL) << "Split Name Dependencies should not be necessary";
+    static std::set<std::string> empty;
+    return empty;
+  }
+
   bool verbose_ = false;
   std::string package_;
 
diff --git a/tools/aapt2/cmd/Diff.cpp b/tools/aapt2/cmd/Diff.cpp
index 262f4fc4e394..d56994e3ae24 100644
--- a/tools/aapt2/cmd/Diff.cpp
+++ b/tools/aapt2/cmd/Diff.cpp
@@ -65,6 +65,12 @@ class DiffContext : public IAaptContext {
     return 0;
   }
 
+  const std::set<std::string>& GetSplitNameDependencies() override {
+    UNIMPLEMENTED(FATAL) << "Split Name Dependencies should not be necessary";
+    static std::set<std::string> empty;
+    return empty;
+  }
+
  private:
   std::string empty_;
   StdErrDiagnostics diagnostics_;
diff --git a/tools/aapt2/cmd/Dump.cpp b/tools/aapt2/cmd/Dump.cpp
index a23a6a46cf0f..3982d12f6036 100644
--- a/tools/aapt2/cmd/Dump.cpp
+++ b/tools/aapt2/cmd/Dump.cpp
@@ -118,6 +118,12 @@ class DumpContext : public IAaptContext {
     return 0;
   }
 
+  const std::set<std::string>& GetSplitNameDependencies() override {
+    UNIMPLEMENTED(FATAL) << "Split Name Dependencies should not be necessary";
+    static std::set<std::string> empty;
+    return empty;
+  }
+
  private:
   StdErrDiagnostics diagnostics_;
   bool verbose_ = false;
@@ -388,6 +394,17 @@ int DumpXmlTreeCommand::Dump(LoadedApk* apk) {
   return 0;
 }
 
+int DumpOverlayableCommand::Dump(LoadedApk* apk) {
+  ResourceTable* table = apk->GetResourceTable();
+  if (!table) {
+    GetDiagnostics()->Error(DiagMessage() << "Failed to retrieve resource table");
+    return 1;
+  }
+
+  Debug::DumpOverlayable(*table, GetPrinter());
+  return 0;
+}
+
 const char DumpBadgerCommand::kBadgerData[2925] = {
     32,  32,  32,  32,  32,  32,  32,  32,  32,  32,  32,  32,  32,  32,  32,  32,  32,  32,  32,
     32,  32,  32,  32,  32,  32,  95,  46,  32,  32,  32,  32,  32,  32,  32,  32,  32,  32,  32,
diff --git a/tools/aapt2/cmd/Dump.h b/tools/aapt2/cmd/Dump.h
index 7ded9bcf8470..cd51f7a7718c 100644
--- a/tools/aapt2/cmd/Dump.h
+++ b/tools/aapt2/cmd/Dump.h
@@ -240,6 +240,16 @@ class DumpXmlTreeCommand : public DumpApkCommand {
   std::vector<std::string> files_;
 };
 
+class DumpOverlayableCommand : public DumpApkCommand {
+ public:
+  explicit DumpOverlayableCommand(text::Printer* printer, IDiagnostics* diag)
+      : DumpApkCommand("overlayable", printer, diag) {
+    SetDescription("Print the <overlayable> resources of an APK.");
+  }
+
+  int Dump(LoadedApk* apk) override;
+};
+
 /** The default dump command. Performs no action because a subcommand is required. */
 class DumpCommand : public Command {
  public:
@@ -255,8 +265,8 @@ class DumpCommand : public Command {
     AddOptionalSubcommand(util::make_unique<DumpTableCommand>(printer, diag_));
     AddOptionalSubcommand(util::make_unique<DumpXmlStringsCommand>(printer, diag_));
     AddOptionalSubcommand(util::make_unique<DumpXmlTreeCommand>(printer, diag_));
+    AddOptionalSubcommand(util::make_unique<DumpOverlayableCommand>(printer, diag_));
     AddOptionalSubcommand(util::make_unique<DumpBadgerCommand>(printer), /* hidden */ true);
-    // TODO(b/120609160): Add aapt2 overlayable dump command
   }
 
   int Action(const std::vector<std::string>& args) override {
diff --git a/tools/aapt2/cmd/Link.cpp b/tools/aapt2/cmd/Link.cpp
index 85414fb8a4e5..72cb41a1b172 100644
--- a/tools/aapt2/cmd/Link.cpp
+++ b/tools/aapt2/cmd/Link.cpp
@@ -140,6 +140,14 @@ class LinkContext : public IAaptContext {
     min_sdk_version_ = minSdk;
   }
 
+  const std::set<std::string>& GetSplitNameDependencies() override {
+    return split_name_dependencies_;
+  }
+
+  void SetSplitNameDependencies(const std::set<std::string>& split_name_dependencies) {
+    split_name_dependencies_ = split_name_dependencies;
+  }
+
  private:
   DISALLOW_COPY_AND_ASSIGN(LinkContext);
 
@@ -151,6 +159,7 @@ class LinkContext : public IAaptContext {
   SymbolTable symbols_;
   bool verbose_ = false;
   int min_sdk_version_ = 0;
+  std::set<std::string> split_name_dependencies_;
 };
 
 // A custom delegate that generates compatible pre-O IDs for use with feature splits.
@@ -269,6 +278,7 @@ struct ResourceFileFlattenerOptions {
   bool keep_raw_values = false;
   bool do_not_compress_anything = false;
   bool update_proguard_spec = false;
+  bool do_not_fail_on_missing_resources = false;
   OutputFormat output_format = OutputFormat::kApk;
   std::unordered_set<std::string> extensions_to_not_compress;
   Maybe<std::regex> regex_to_not_compress;
@@ -297,6 +307,25 @@ struct R {
   };
 };
 
+template <typename T>
+uint32_t GetCompressionFlags(const StringPiece& str, T options) {
+  if (options.do_not_compress_anything) {
+    return 0;
+  }
+
+  if (options.regex_to_not_compress
+      && std::regex_search(str.to_string(), options.regex_to_not_compress.value())) {
+    return 0;
+  }
+
+  for (const std::string& extension : options.extensions_to_not_compress) {
+    if (util::EndsWith(str, extension)) {
+      return 0;
+    }
+  }
+  return ArchiveEntry::kCompress;
+}
+
 class ResourceFileFlattener {
  public:
   ResourceFileFlattener(const ResourceFileFlattenerOptions& options, IAaptContext* context,
@@ -321,8 +350,6 @@ class ResourceFileFlattener {
     std::string dst_path;
   };
 
-  uint32_t GetCompressionFlags(const StringPiece& str);
-
   std::vector<std::unique_ptr<xml::XmlResource>> LinkAndVersionXmlFile(ResourceTable* table,
                                                                        FileOperation* file_op);
 
@@ -381,26 +408,6 @@ ResourceFileFlattener::ResourceFileFlattener(const ResourceFileFlattenerOptions&
   }
 }
 
-// TODO(rtmitchell): turn this function into a variable that points to a method that retrieves the
-// compression flag
-uint32_t ResourceFileFlattener::GetCompressionFlags(const StringPiece& str) {
-  if (options_.do_not_compress_anything) {
-    return 0;
-  }
-
-  if (options_.regex_to_not_compress
-      && std::regex_search(str.to_string(), options_.regex_to_not_compress.value())) {
-    return 0;
-  }
-
-  for (const std::string& extension : options_.extensions_to_not_compress) {
-    if (util::EndsWith(str, extension)) {
-      return 0;
-    }
-  }
-  return ArchiveEntry::kCompress;
-}
-
 static bool IsTransitionElement(const std::string& name) {
   return name == "fade" || name == "changeBounds" || name == "slide" || name == "explode" ||
          name == "changeImageTransform" || name == "changeTransform" ||
@@ -438,7 +445,7 @@ std::vector<std::unique_ptr<xml::XmlResource>> ResourceFileFlattener::LinkAndVer
   xml::StripAndroidStudioAttributes(doc->root.get());
 
   XmlReferenceLinker xml_linker;
-  if (!xml_linker.Consume(context_, doc)) {
+  if (!options_.do_not_fail_on_missing_resources && !xml_linker.Consume(context_, doc)) {
     return {};
   }
 
@@ -640,7 +647,8 @@ bool ResourceFileFlattener::Flatten(ResourceTable* table, IArchiveWriter* archiv
           }
         } else {
           error |= !io::CopyFileToArchive(context_, file_op.file_to_copy, file_op.dst_path,
-                                          GetCompressionFlags(file_op.dst_path), archive_writer);
+                                          GetCompressionFlags(file_op.dst_path, options_),
+                                          archive_writer);
         }
       }
     }
@@ -887,7 +895,7 @@ class Linker {
           // android:versionCode from the framework AndroidManifest.xml.
           ExtractCompileSdkVersions(asset_source->GetAssetManager());
         }
-      } else if (asset_source->IsPackageDynamic(entry.first)) {
+      } else if (asset_source->IsPackageDynamic(entry.first, entry.second)) {
         final_table_.included_packages_[entry.first] = entry.second;
       }
     }
@@ -965,6 +973,17 @@ class Linker {
         app_info.min_sdk_version = ResourceUtils::ParseSdkVersion(min_sdk->value);
       }
     }
+
+    for (const xml::Element* child_el : manifest_el->GetChildElements()) {
+      if (child_el->namespace_uri.empty() && child_el->name == "uses-split") {
+        if (const xml::Attribute* split_name =
+            child_el->FindAttribute(xml::kSchemaAndroid, "name")) {
+          if (!split_name->value.empty()) {
+            app_info.split_name_dependencies.insert(split_name->value);
+          }
+        }
+      }
+    }
     return app_info;
   }
 
@@ -1065,7 +1084,8 @@ class Linker {
 
       case OutputFormat::kProto: {
         pb::ResourceTable pb_table;
-        SerializeTableToPb(*table, &pb_table, context_->GetDiagnostics());
+        SerializeTableToPb(*table, &pb_table, context_->GetDiagnostics(),
+                           options_.proto_table_flattener_options);
         return io::CopyProtoToArchive(context_, &pb_table, kProtoResourceTablePath,
                                       ArchiveEntry::kCompress, writer);
       } break;
@@ -1278,7 +1298,8 @@ class Linker {
       return false;
     }
 
-    proguard::WriteKeepSet(keep_set, &fout, options_.generate_minimal_proguard_rules);
+    proguard::WriteKeepSet(keep_set, &fout, options_.generate_minimal_proguard_rules,
+                           options_.no_proguard_location_reference);
     fout.Flush();
 
     if (fout.HadError()) {
@@ -1548,16 +1569,7 @@ class Linker {
     }
 
     for (auto& entry : merged_assets) {
-      uint32_t compression_flags = ArchiveEntry::kCompress;
-      std::string extension = file::GetExtension(entry.first).to_string();
-
-      if (options_.do_not_compress_anything
-          || options_.extensions_to_not_compress.count(extension) > 0
-          || (options_.regex_to_not_compress
-              && std::regex_search(extension, options_.regex_to_not_compress.value()))) {
-        compression_flags = 0u;
-      }
-
+      uint32_t compression_flags = GetCompressionFlags(entry.first, options_);
       if (!io::CopyFileToArchive(context_, entry.second.get(), entry.first, compression_flags,
                                  writer)) {
         return false;
@@ -1566,6 +1578,93 @@ class Linker {
     return true;
   }
 
+  void AliasAdaptiveIcon(xml::XmlResource* manifest, ResourceTable* table) {
+    xml::Element* application = manifest->root->FindChild("", "application");
+    if (!application) {
+      return;
+    }
+
+    xml::Attribute* icon = application->FindAttribute(xml::kSchemaAndroid, "icon");
+    xml::Attribute* round_icon = application->FindAttribute(xml::kSchemaAndroid, "roundIcon");
+    if (!icon || !round_icon) {
+      return;
+    }
+
+    // Find the icon resource defined within the application.
+    auto icon_reference = ValueCast<Reference>(icon->compiled_value.get());
+    if (!icon_reference || !icon_reference->name) {
+      return;
+    }
+    auto package = table->FindPackageById(icon_reference->id.value().package_id());
+    if (!package) {
+      return;
+    }
+    auto type = package->FindType(icon_reference->name.value().type);
+    if (!type) {
+      return;
+    }
+    auto icon_entry = type->FindEntry(icon_reference->name.value().entry);
+    if (!icon_entry) {
+      return;
+    }
+
+    int icon_max_sdk = 0;
+    for (auto& config_value : icon_entry->values) {
+      icon_max_sdk = (icon_max_sdk < config_value->config.sdkVersion)
+          ? config_value->config.sdkVersion : icon_max_sdk;
+    }
+    if (icon_max_sdk < SDK_O) {
+      // Adaptive icons must be versioned with v26 qualifiers, so this is not an adaptive icon.
+      return;
+    }
+
+    // Find the roundIcon resource defined within the application.
+    auto round_icon_reference = ValueCast<Reference>(round_icon->compiled_value.get());
+    if (!round_icon_reference || !round_icon_reference->name) {
+      return;
+    }
+    package = table->FindPackageById(round_icon_reference->id.value().package_id());
+    if (!package) {
+      return;
+    }
+    type = package->FindType(round_icon_reference->name.value().type);
+    if (!type) {
+      return;
+    }
+    auto round_icon_entry = type->FindEntry(round_icon_reference->name.value().entry);
+    if (!round_icon_entry) {
+      return;
+    }
+
+    int round_icon_max_sdk = 0;
+    for (auto& config_value : round_icon_entry->values) {
+      round_icon_max_sdk = (round_icon_max_sdk < config_value->config.sdkVersion)
+                     ? config_value->config.sdkVersion : round_icon_max_sdk;
+    }
+    if (round_icon_max_sdk >= SDK_O) {
+      // The developer explicitly used a v26 compatible drawable as the roundIcon, meaning we should
+      // not generate an alias to the icon drawable.
+      return;
+    }
+
+    // Add an equivalent v26 entry to the roundIcon for each v26 variant of the regular icon.
+    for (auto& config_value : icon_entry->values) {
+      if (config_value->config.sdkVersion < SDK_O) {
+        continue;
+      }
+
+      context_->GetDiagnostics()->Note(DiagMessage() << "generating "
+                                                     << round_icon_reference->name.value()
+                                                     << " with config \"" << config_value->config
+                                                     << "\" for round icon compatibility");
+
+      auto value = icon_reference->Clone(&table->string_pool);
+      auto round_config_value = round_icon_entry->FindOrCreateValue(
+          config_value->config, config_value->product);
+      round_config_value->value.reset(value);
+    }
+  }
+
   // Writes the AndroidManifest, ResourceTable, and all XML files referenced by the ResourceTable
   // to the IArchiveWriter.
   bool WriteApk(IArchiveWriter* writer, proguard::KeepSet* keep_set, xml::XmlResource* manifest,
@@ -1579,6 +1678,14 @@ class Linker {
       return false;
     }
 
+    // When a developer specifies an adaptive application icon, and a non-adaptive round application
+    // icon, create an alias from the round icon to the regular icon for v26 APIs and up. We do this
+    // because certain devices prefer android:roundIcon over android:icon regardless of the API
+    // levels of the drawables set for either. This auto-aliasing behaviour allows an app to prefer
+    // the android:roundIcon on API 25 devices, and prefer the adaptive icon on API 26 devices.
+    // See (b/34829129)
+    AliasAdaptiveIcon(manifest, table);
+
     ResourceFileFlattenerOptions file_flattener_options;
     file_flattener_options.keep_raw_values = keep_raw_values;
     file_flattener_options.do_not_compress_anything = options_.do_not_compress_anything;
@@ -1591,9 +1698,9 @@ class Linker {
     file_flattener_options.update_proguard_spec =
         static_cast<bool>(options_.generate_proguard_rules_path);
     file_flattener_options.output_format = options_.output_format;
+    file_flattener_options.do_not_fail_on_missing_resources = options_.merge_only;
 
     ResourceFileFlattener file_flattener(file_flattener_options, context_, keep_set);
-
     if (!file_flattener.Flatten(table, writer)) {
       context_->GetDiagnostics()->Error(DiagMessage() << "failed linking file resources");
       return false;
@@ -1660,10 +1767,9 @@ class Linker {
       return 1;
     }
 
-    // First extract the package name without modifying it (via --rename-manifest-package).
+    // First extract the Package name without modifying it (via --rename-manifest-package).
     if (Maybe<AppInfo> maybe_app_info =
             ExtractAppInfoFromManifest(manifest_xml.get(), context_->GetDiagnostics())) {
-      // Extract the package name from the manifest ignoring the value of --rename-manifest-package.
       const AppInfo& app_info = maybe_app_info.value();
       context_->SetCompilationPackage(app_info.package);
     }
@@ -1699,6 +1805,7 @@ class Linker {
     context_->SetMinSdkVersion(app_info_.min_sdk_version.value_or_default(0));
 
     context_->SetNameManglerPolicy(NameManglerPolicy{context_->GetCompilationPackage()});
+    context_->SetSplitNameDependencies(app_info_.split_name_dependencies);
 
     // Override the package ID when it is "android".
     if (context_->GetCompilationPackage() == "android") {
@@ -1714,6 +1821,8 @@ class Linker {
 
     TableMergerOptions table_merger_options;
     table_merger_options.auto_add_overlay = options_.auto_add_overlay;
+    table_merger_options.override_styles_instead_of_overlaying =
+        options_.override_styles_instead_of_overlaying;
     table_merger_options.strict_visibility = options_.strict_visibility;
     table_merger_ = util::make_unique<TableMerger>(context_, &final_table_, table_merger_options);
 
@@ -1828,7 +1937,7 @@ class Linker {
     }
 
     ReferenceLinker linker;
-    if (!linker.Consume(context_, &final_table_)) {
+    if (!options_.merge_only && !linker.Consume(context_, &final_table_)) {
       context_->GetDiagnostics()->Error(DiagMessage() << "failed linking references");
       return 1;
     }
@@ -1980,7 +2089,7 @@ class Linker {
       manifest_xml->file.name.package = context_->GetCompilationPackage();
 
       XmlReferenceLinker manifest_linker;
-      if (manifest_linker.Consume(context_, manifest_xml.get())) {
+      if (options_.merge_only || manifest_linker.Consume(context_, manifest_xml.get())) {
         if (options_.generate_proguard_rules_path &&
             !proguard::CollectProguardRulesForManifest(manifest_xml.get(), &proguard_keep_set)) {
           error = true;
@@ -2114,6 +2223,12 @@ int LinkCommand::Action(const std::vector<std::string>& args) {
     return 1;
   }
 
+  if (options_.merge_only && !static_lib_) {
+    context.GetDiagnostics()->Error(
+        DiagMessage() << "the --merge-only flag can be only used when building a static library");
+    return 1;
+  }
+
   // The default build type.
   context.SetPackageType(PackageType::kApp);
   context.SetPackageId(kAppPackageId);
diff --git a/tools/aapt2/cmd/Link.h b/tools/aapt2/cmd/Link.h
index e62e0a6b9f62..852b1244cd6e 100644
--- a/tools/aapt2/cmd/Link.h
+++ b/tools/aapt2/cmd/Link.h
@@ -24,6 +24,7 @@
 #include "Resource.h"
 #include "split/TableSplitter.h"
 #include "format/binary/TableFlattener.h"
+#include "format/proto/ProtoSerialize.h"
 #include "link/ManifestFixer.h"
 #include "trace/TraceBuffer.h"
 
@@ -42,6 +43,7 @@ struct LinkOptions {
   std::vector<std::string> assets_dirs;
   bool output_to_directory = false;
   bool auto_add_overlay = false;
+  bool override_styles_instead_of_overlaying = false;
   OutputFormat output_format = OutputFormat::kApk;
   Maybe<std::string> rename_resources_package;
 
@@ -55,6 +57,7 @@ struct LinkOptions {
   bool generate_conditional_proguard_rules = false;
   bool generate_minimal_proguard_rules = false;
   bool generate_non_final_ids = false;
+  bool no_proguard_location_reference = false;
   std::vector<std::string> javadoc_annotations;
   Maybe<std::string> private_symbols;
 
@@ -71,6 +74,7 @@ struct LinkOptions {
 
   // Static lib options.
   bool no_static_lib_packages = false;
+  bool merge_only = false;
 
   // AndroidManifest.xml massaging options.
   ManifestFixerOptions manifest_fixer_options;
@@ -80,6 +84,7 @@ struct LinkOptions {
 
   // Flattening options.
   TableFlattenerOptions table_flattener_options;
+  SerializeTableOptions proto_table_flattener_options;
   bool keep_raw_values = false;
 
   // Split APK options.
@@ -212,6 +217,9 @@ class LinkCommand : public Command {
         "Generates R.java without the final modifier. This is implied when\n"
             "--static-lib is specified.",
         &options_.generate_non_final_ids);
+    AddOptionalSwitch("--no-proguard-location-reference",
+        "Keep proguard rules files from having a reference to the source file",
+        &options_.no_proguard_location_reference);
     AddOptionalFlag("--stable-ids", "File containing a list of name to ID mapping.",
         &stable_id_file_path_);
     AddOptionalFlag("--emit-ids",
@@ -243,6 +251,10 @@ class LinkCommand : public Command {
         "Allows the addition of new resources in overlays without\n"
             "<add-resource> tags.",
         &options_.auto_add_overlay);
+    AddOptionalSwitch("--override-styles-instead-of-overlaying",
+        "Causes styles defined in -R resources to replace previous definitions\n"
+            "instead of merging into them\n",
+        &options_.override_styles_instead_of_overlaying);
     AddOptionalFlag("--rename-manifest-package", "Renames the package in AndroidManifest.xml.",
         &options_.manifest_fixer_options.rename_manifest_package);
     AddOptionalFlag("--rename-resources-package", "Renames the package in resources table",
@@ -255,7 +267,7 @@ class LinkCommand : public Command {
         "Changes the name of the target package for overlay. Most useful\n"
             "when used in conjunction with --rename-manifest-package.",
         &options_.manifest_fixer_options.rename_overlay_target_package);
-    AddOptionalFlagList("-0", "File extensions not to compress.",
+    AddOptionalFlagList("-0", "File suffix not to compress.",
         &options_.extensions_to_not_compress);
     AddOptionalSwitch("--no-compress", "Do not compress any resources.",
         &options_.do_not_compress_anything);
@@ -263,8 +275,8 @@ class LinkCommand : public Command {
         &options_.keep_raw_values);
     AddOptionalFlag("--no-compress-regex",
         "Do not compress extensions matching the regular expression. Remember to\n"
-            " use the '$' symbol for end of line. Uses a non case-sensitive\n"
-            " ECMAScript regular expression grammar.",
+            "use the '$' symbol for end of line. Uses a case-sensitive ECMAScript"
+            "regular expression grammar.",
         &no_compress_regex);
     AddOptionalSwitch("--warn-manifest-validation",
         "Treat manifest validation errors as warnings.",
@@ -284,9 +296,18 @@ class LinkCommand : public Command {
     AddOptionalSwitch("--strict-visibility",
         "Do not allow overlays with different visibility levels.",
         &options_.strict_visibility);
+    AddOptionalSwitch("--exclude-sources",
+        "Do not serialize source file information when generating resources in\n"
+            "Protobuf format.",
+        &options_.proto_table_flattener_options.exclude_sources);
+    AddOptionalFlag("--trace-folder",
+        "Generate systrace json trace fragment to specified folder.",
+        &trace_folder_);
+    AddOptionalSwitch("--merge-only",
+        "Only merge the resources, without verifying resource references. This flag\n"
+            "should only be used together with the --static-lib flag.",
+        &options_.merge_only);
     AddOptionalSwitch("-v", "Enables verbose logging.", &verbose_);
-    AddOptionalFlag("--trace-folder", "Generate systrace json trace fragment to specified folder.",
-                    &trace_folder_);
   }
 
   int Action(const std::vector<std::string>& args) override;
diff --git a/tools/aapt2/cmd/Link_test.cpp b/tools/aapt2/cmd/Link_test.cpp
index 9ea93f638aff..062dd8eac975 100644
--- a/tools/aapt2/cmd/Link_test.cpp
+++ b/tools/aapt2/cmd/Link_test.cpp
@@ -14,6 +14,7 @@
  * limitations under the License.
  */
 
+#include "AppInfo.h"
 #include "Link.h"
 
 #include "LoadedApk.h"
@@ -43,10 +44,8 @@ TEST_F(LinkTest, RemoveRawXmlStrings) {
   // Load the binary xml tree
   android::ResXMLTree tree;
   std::unique_ptr<LoadedApk> apk = LoadedApk::LoadApkFromPath(out_apk, &diag);
-
   std::unique_ptr<io::IData> data = OpenFileAsData(apk.get(), "res/xml/test.xml");
   ASSERT_THAT(data, Ne(nullptr));
-
   AssertLoadXml(apk.get(), data.get(), &tree);
 
   // Check that the raw string index has not been assigned
@@ -71,10 +70,8 @@ TEST_F(LinkTest, KeepRawXmlStrings) {
   // Load the binary xml tree
   android::ResXMLTree tree;
   std::unique_ptr<LoadedApk> apk = LoadedApk::LoadApkFromPath(out_apk, &diag);
-
   std::unique_ptr<io::IData> data = OpenFileAsData(apk.get(), "res/xml/test.xml");
   ASSERT_THAT(data, Ne(nullptr));
-
   AssertLoadXml(apk.get(), data.get(), &tree);
 
   // Check that the raw string index has been set to the correct string pool entry
@@ -83,4 +80,241 @@ TEST_F(LinkTest, KeepRawXmlStrings) {
   EXPECT_THAT(util::GetString(tree.getStrings(), static_cast<size_t>(raw_index)), Eq("007"));
 }
 
-}  // namespace aapt
\ No newline at end of file
+TEST_F(LinkTest, NoCompressAssets) {
+  StdErrDiagnostics diag;
+  std::string content(500, 'a');
+  WriteFile(GetTestPath("assets/testtxt"), content);
+  WriteFile(GetTestPath("assets/testtxt2"), content);
+  WriteFile(GetTestPath("assets/test.txt"), content);
+  WriteFile(GetTestPath("assets/test.hello.txt"), content);
+  WriteFile(GetTestPath("assets/test.hello.xml"), content);
+
+  const std::string out_apk = GetTestPath("out.apk");
+  std::vector<std::string> link_args = {
+      "--manifest", GetDefaultManifest(),
+      "-o", out_apk,
+      "-0", ".txt",
+      "-0", "txt2",
+      "-0", ".hello.txt",
+      "-0", "hello.xml",
+      "-A", GetTestPath("assets")
+  };
+
+  ASSERT_TRUE(Link(link_args, &diag));
+
+  std::unique_ptr<LoadedApk> apk = LoadedApk::LoadApkFromPath(out_apk, &diag);
+  ASSERT_THAT(apk, Ne(nullptr));
+  io::IFileCollection* zip = apk->GetFileCollection();
+  ASSERT_THAT(zip, Ne(nullptr));
+
+  auto file = zip->FindFile("assets/testtxt");
+  ASSERT_THAT(file, Ne(nullptr));
+  EXPECT_TRUE(file->WasCompressed());
+
+  file = zip->FindFile("assets/testtxt2");
+  ASSERT_THAT(file, Ne(nullptr));
+  EXPECT_FALSE(file->WasCompressed());
+
+  file = zip->FindFile("assets/test.txt");
+  ASSERT_THAT(file, Ne(nullptr));
+  EXPECT_FALSE(file->WasCompressed());
+
+  file = zip->FindFile("assets/test.hello.txt");
+  ASSERT_THAT(file, Ne(nullptr));
+  EXPECT_FALSE(file->WasCompressed());
+
+  file = zip->FindFile("assets/test.hello.xml");
+  ASSERT_THAT(file, Ne(nullptr));
+  EXPECT_FALSE(file->WasCompressed());
+}
+
+TEST_F(LinkTest, NoCompressResources) {
+  StdErrDiagnostics diag;
+  std::string content(500, 'a');
+  const std::string compiled_files_dir = GetTestPath("compiled");
+  ASSERT_TRUE(CompileFile(GetTestPath("res/raw/testtxt"), content, compiled_files_dir, &diag));
+  ASSERT_TRUE(CompileFile(GetTestPath("res/raw/test.txt"), content, compiled_files_dir, &diag));
+  ASSERT_TRUE(CompileFile(GetTestPath("res/raw/test1.hello.txt"), content, compiled_files_dir,
+              &diag));
+  ASSERT_TRUE(CompileFile(GetTestPath("res/raw/test2.goodbye.xml"), content, compiled_files_dir,
+              &diag));
+
+  const std::string out_apk = GetTestPath("out.apk");
+  std::vector<std::string> link_args = {
+      "--manifest", GetDefaultManifest(),
+      "-o", out_apk,
+      "-0", ".txt",
+      "-0", ".hello.txt",
+      "-0", "goodbye.xml",
+  };
+
+  ASSERT_TRUE(Link(link_args, compiled_files_dir, &diag));
+
+  std::unique_ptr<LoadedApk> apk = LoadedApk::LoadApkFromPath(out_apk, &diag);
+  ASSERT_THAT(apk, Ne(nullptr));
+  io::IFileCollection* zip = apk->GetFileCollection();
+  ASSERT_THAT(zip, Ne(nullptr));
+
+  auto file = zip->FindFile("res/raw/testtxt");
+  ASSERT_THAT(file, Ne(nullptr));
+  EXPECT_TRUE(file->WasCompressed());
+
+  file = zip->FindFile("res/raw/test.txt");
+  ASSERT_THAT(file, Ne(nullptr));
+  EXPECT_FALSE(file->WasCompressed());
+
+  file = zip->FindFile("res/raw/test1.hello.hello.txt");
+  ASSERT_THAT(file, Ne(nullptr));
+  EXPECT_FALSE(file->WasCompressed());
+
+  file = zip->FindFile("res/raw/test2.goodbye.goodbye.xml");
+  ASSERT_THAT(file, Ne(nullptr));
+  EXPECT_FALSE(file->WasCompressed());
+}
+
+TEST_F(LinkTest, OverlayStyles) {
+  StdErrDiagnostics diag;
+  const std::string compiled_files_dir = GetTestPath("compiled");
+  const std::string override_files_dir = GetTestPath("compiled-override");
+  ASSERT_TRUE(CompileFile(GetTestPath("res/values/values.xml"),
+                          R"(<resources>
+                               <style name="MyStyle">
+                                 <item name="android:textColor">#123</item>
+                               </style>
+                             </resources>)",
+                          compiled_files_dir, &diag));
+  ASSERT_TRUE(CompileFile(GetTestPath("res/values/values-override.xml"),
+                          R"(<resources>
+                               <style name="MyStyle">
+                                 <item name="android:background">#456</item>
+                               </style>
+                             </resources>)",
+                          override_files_dir, &diag));
+
+
+  const std::string out_apk = GetTestPath("out.apk");
+  std::vector<std::string> link_args = {
+      "--manifest", GetDefaultManifest(kDefaultPackageName),
+      "-o", out_apk,
+  };
+  const auto override_files = file::FindFiles(override_files_dir, &diag);
+  for (const auto &override_file : override_files.value()) {
+      link_args.push_back("-R");
+      link_args.push_back(file::BuildPath({override_files_dir, override_file}));
+  }
+  ASSERT_TRUE(Link(link_args, compiled_files_dir, &diag));
+
+  std::unique_ptr<LoadedApk> apk = LoadedApk::LoadApkFromPath(out_apk, &diag);
+  const Style* actual_style = test::GetValue<Style>(
+      apk->GetResourceTable(), std::string(kDefaultPackageName) + ":style/MyStyle");
+  ASSERT_NE(actual_style, nullptr);
+  ASSERT_EQ(actual_style->entries.size(), 2);
+  EXPECT_EQ(actual_style->entries[0].key.id, 0x01010098);  // android:textColor
+  EXPECT_EQ(actual_style->entries[1].key.id, 0x010100d4);  // android:background
+}
+
+TEST_F(LinkTest, OverrideStylesInsteadOfOverlaying) {
+  StdErrDiagnostics diag;
+  const std::string compiled_files_dir = GetTestPath("compiled");
+  const std::string override_files_dir = GetTestPath("compiled-override");
+  ASSERT_TRUE(CompileFile(GetTestPath("res/values/values.xml"),
+                          R"(<resources>
+                               <style name="MyStyle">
+                                 <item name="android:textColor">#123</item>
+                               </style>
+                             </resources>)",
+                          compiled_files_dir, &diag));
+  ASSERT_TRUE(CompileFile(GetTestPath("res/values/values-override.xml"),
+                          R"(<resources>
+                               <style name="MyStyle">
+                                 <item name="android:background">#456</item>
+                               </style>
+                             </resources>)",
+                          override_files_dir, &diag));
+
+
+  const std::string out_apk = GetTestPath("out.apk");
+  std::vector<std::string> link_args = {
+      "--manifest", GetDefaultManifest(kDefaultPackageName),
+      "--override-styles-instead-of-overlaying",
+      "-o", out_apk,
+  };
+  const auto override_files = file::FindFiles(override_files_dir, &diag);
+  for (const auto &override_file : override_files.value()) {
+      link_args.push_back("-R");
+      link_args.push_back(file::BuildPath({override_files_dir, override_file}));
+  }
+  ASSERT_TRUE(Link(link_args, compiled_files_dir, &diag));
+
+  std::unique_ptr<LoadedApk> apk = LoadedApk::LoadApkFromPath(out_apk, &diag);
+  const Style* actual_style = test::GetValue<Style>(
+      apk->GetResourceTable(), std::string(kDefaultPackageName) + ":style/MyStyle");
+  ASSERT_NE(actual_style, nullptr);
+  ASSERT_EQ(actual_style->entries.size(), 1);
+  EXPECT_EQ(actual_style->entries[0].key.id, 0x010100d4);  // android:background
+}
+
+TEST_F(LinkTest, AppInfoWithUsesSplit) {
+  StdErrDiagnostics diag;
+  const std::string base_files_dir = GetTestPath("base");
+  ASSERT_TRUE(CompileFile(GetTestPath("res/values/values.xml"),
+                          R"(<resources>
+                               <string name="bar">bar</string>
+                             </resources>)",
+                          base_files_dir, &diag));
+  const std::string base_apk = GetTestPath("base.apk");
+  std::vector<std::string> link_args = {
+      "--manifest", GetDefaultManifest("com.aapt2.app"),
+      "-o", base_apk,
+  };
+  ASSERT_TRUE(Link(link_args, base_files_dir, &diag));
+
+  const std::string feature_manifest = GetTestPath("feature_manifest.xml");
+  WriteFile(feature_manifest, android::base::StringPrintf(R"(
+      <manifest xmlns:android="http://schemas.android.com/apk/res/android"
+          package="com.aapt2.app" split="feature1">
+      </manifest>)"));
+  const std::string feature_files_dir = GetTestPath("feature");
+  ASSERT_TRUE(CompileFile(GetTestPath("res/values/values.xml"),
+                          R"(<resources>
+                               <string name="foo">foo</string>
+                             </resources>)",
+                          feature_files_dir, &diag));
+  const std::string feature_apk = GetTestPath("feature.apk");
+  const std::string feature_package_id = "0x80";
+  link_args = {
+      "--manifest", feature_manifest,
+      "-I", base_apk,
+      "--package-id", feature_package_id,
+      "-o", feature_apk,
+  };
+  ASSERT_TRUE(Link(link_args, feature_files_dir, &diag));
+
+  const std::string feature2_manifest = GetTestPath("feature2_manifest.xml");
+  WriteFile(feature2_manifest, android::base::StringPrintf(R"(
+        <manifest xmlns:android="http://schemas.android.com/apk/res/android"
+            package="com.aapt2.app" split="feature2">
+          <uses-split android:name="feature1"/>
+        </manifest>)"));
+  const std::string feature2_files_dir = GetTestPath("feature2");
+  ASSERT_TRUE(CompileFile(GetTestPath("res/values/values.xml"),
+                          R"(<resources>
+                               <string-array name="string_array">
+                                 <item>@string/bar</item>
+                                 <item>@string/foo</item>
+                               </string-array>
+                             </resources>)",
+                          feature2_files_dir, &diag));
+  const std::string feature2_apk = GetTestPath("feature2.apk");
+  const std::string feature2_package_id = "0x81";
+  link_args = {
+      "--manifest", feature2_manifest,
+      "-I", base_apk,
+      "-I", feature_apk,
+      "--package-id", feature2_package_id,
+      "-o", feature2_apk,
+  };
+  ASSERT_TRUE(Link(link_args, feature2_files_dir, &diag));
+}
+
+}  // namespace aapt
diff --git a/tools/aapt2/cmd/Optimize.cpp b/tools/aapt2/cmd/Optimize.cpp
index 2e6af18c1948..e36668e5a043 100644
--- a/tools/aapt2/cmd/Optimize.cpp
+++ b/tools/aapt2/cmd/Optimize.cpp
@@ -53,9 +53,9 @@ using ::android::ConfigDescription;
 using ::android::ResTable_config;
 using ::android::StringPiece;
 using ::android::base::ReadFileToString;
-using ::android::base::WriteStringToFile;
 using ::android::base::StringAppendF;
 using ::android::base::StringPrintf;
+using ::android::base::WriteStringToFile;
 
 namespace aapt {
 
@@ -108,6 +108,12 @@ class OptimizeContext : public IAaptContext {
     return sdk_version_;
   }
 
+  const std::set<std::string>& GetSplitNameDependencies() override {
+    UNIMPLEMENTED(FATAL) << "Split Name Dependencies should not be necessary";
+    static std::set<std::string> empty;
+    return empty;
+  }
+
  private:
   DISALLOW_COPY_AND_ASSIGN(OptimizeContext);
 
@@ -294,29 +300,7 @@ class Optimizer {
   OptimizeContext* context_;
 };
 
-bool ExtractObfuscationWhitelistFromConfig(const std::string& path, OptimizeContext* context,
-                                           OptimizeOptions* options) {
-  std::string contents;
-  if (!ReadFileToString(path, &contents, true)) {
-    context->GetDiagnostics()->Error(DiagMessage()
-                                     << "failed to parse whitelist from config file: " << path);
-    return false;
-  }
-  for (StringPiece resource_name : util::Tokenize(contents, ',')) {
-    options->table_flattener_options.whitelisted_resources.insert(
-        resource_name.to_string());
-  }
-  return true;
-}
-
-bool ExtractConfig(const std::string& path, OptimizeContext* context,
-                                    OptimizeOptions* options) {
-  std::string content;
-  if (!android::base::ReadFileToString(path, &content, true /*follow_symlinks*/)) {
-    context->GetDiagnostics()->Error(DiagMessage(path) << "failed reading whitelist");
-    return false;
-  }
-
+bool ParseConfig(const std::string& content, IAaptContext* context, OptimizeOptions* options) {
   size_t line_no = 0;
   for (StringPiece line : util::Tokenize(content, '\n')) {
     line_no++;
@@ -345,15 +329,24 @@ bool ExtractConfig(const std::string& path, OptimizeContext* context,
     for (StringPiece directive : util::Tokenize(directives, ',')) {
       if (directive == "remove") {
         options->resources_blacklist.insert(resource_name.ToResourceName());
-      } else if (directive == "no_obfuscate") {
-        options->table_flattener_options.whitelisted_resources.insert(
-            resource_name.entry.to_string());
+      } else if (directive == "no_collapse" || directive == "no_obfuscate") {
+        options->table_flattener_options.name_collapse_exemptions.insert(
+            resource_name.ToResourceName());
       }
     }
   }
   return true;
 }
 
+bool ExtractConfig(const std::string& path, IAaptContext* context, OptimizeOptions* options) {
+  std::string content;
+  if (!android::base::ReadFileToString(path, &content, true /*follow_symlinks*/)) {
+    context->GetDiagnostics()->Error(DiagMessage(path) << "failed reading config file");
+    return false;
+  }
+  return ParseConfig(content, context, options);
+}
+
 bool ExtractAppDataFromManifest(OptimizeContext* context, const LoadedApk* apk,
                                 OptimizeOptions* out_options) {
   const xml::XmlResource* manifest = apk->GetManifest();
@@ -461,15 +454,6 @@ int OptimizeCommand::Action(const std::vector<std::string>& args) {
     }
   }
 
-  if (options_.table_flattener_options.collapse_key_stringpool) {
-    if (whitelist_path_) {
-      std::string& path = whitelist_path_.value();
-      if (!ExtractObfuscationWhitelistFromConfig(path, &context, &options_)) {
-        return 1;
-      }
-    }
-  }
-
   if (resources_config_path_) {
     std::string& path = resources_config_path_.value();
     if (!ExtractConfig(path, &context, &options_)) {
diff --git a/tools/aapt2/cmd/Optimize.h b/tools/aapt2/cmd/Optimize.h
index 7f4a3ed85364..5070ccc8afbf 100644
--- a/tools/aapt2/cmd/Optimize.h
+++ b/tools/aapt2/cmd/Optimize.h
@@ -57,7 +57,7 @@ struct OptimizeOptions {
   std::unordered_set<std::string> kept_artifacts;
 
   // Whether or not to shorten resource paths in the APK.
-  bool shorten_resource_paths;
+  bool shorten_resource_paths = false;
 
   // Path to the output map of original resource paths to shortened paths.
   Maybe<std::string> shortened_paths_map_path;
@@ -78,10 +78,6 @@ class OptimizeCommand : public Command {
             "All the resources that would be unused on devices of the given densities will be \n"
             "removed from the APK.",
         &target_densities_);
-    AddOptionalFlag("--whitelist-path",
-        "Path to the whitelist.cfg file containing whitelisted resources \n"
-            "whose names should not be altered in final resource tables.",
-        &whitelist_path_);
     AddOptionalFlag("--resources-config-path",
         "Path to the resources.cfg file containing the list of resources and \n"
             "directives to each resource. \n"
@@ -104,11 +100,13 @@ class OptimizeCommand : public Command {
         "Enables encoding sparse entries using a binary search tree.\n"
             "This decreases APK size at the cost of resource retrieval performance.",
         &options_.table_flattener_options.use_sparse_entries);
-    AddOptionalSwitch("--enable-resource-obfuscation",
-        "Enables obfuscation of key string pool to single value",
+    AddOptionalSwitch("--collapse-resource-names",
+        "Collapses resource names to a single value in the key string pool. Resources can \n"
+            "be exempted using the \"no_collapse\" directive in a file specified by "
+            "--resources-config-path.",
         &options_.table_flattener_options.collapse_key_stringpool);
-    AddOptionalSwitch("--enable-resource-path-shortening",
-        "Enables shortening of the path of the resources inside the APK.",
+    AddOptionalSwitch("--shorten-resource-paths",
+        "Shortens the paths of resources inside the APK.",
         &options_.shorten_resource_paths);
     AddOptionalFlag("--resource-path-shortening-map",
         "Path to output the map of old resource paths to shortened paths.",
@@ -125,7 +123,6 @@ class OptimizeCommand : public Command {
                                const std::string &file_path);
 
   Maybe<std::string> config_path_;
-  Maybe<std::string> whitelist_path_;
   Maybe<std::string> resources_config_path_;
   Maybe<std::string> target_densities_;
   std::vector<std::string> configs_;
diff --git a/tools/aapt2/cmd/Optimize_test.cpp b/tools/aapt2/cmd/Optimize_test.cpp
new file mode 100644
index 000000000000..ac681e85b3d6
--- /dev/null
+++ b/tools/aapt2/cmd/Optimize_test.cpp
@@ -0,0 +1,68 @@
+/*
+ * Copyright (C) 2019 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "Optimize.h"
+
+#include "AppInfo.h"
+#include "Diagnostics.h"
+#include "LoadedApk.h"
+#include "Resource.h"
+#include "test/Test.h"
+
+using testing::Contains;
+using testing::Eq;
+
+namespace aapt {
+
+bool ParseConfig(const std::string&, IAaptContext*, OptimizeOptions*);
+
+using OptimizeTest = CommandTestFixture;
+
+TEST_F(OptimizeTest, ParseConfigWithNoCollapseExemptions) {
+  const std::string& content = R"(
+string/foo#no_collapse
+dimen/bar#no_collapse
+)";
+  aapt::test::Context context;
+  OptimizeOptions options;
+  ParseConfig(content, &context, &options);
+
+  const std::set<ResourceName>& name_collapse_exemptions =
+      options.table_flattener_options.name_collapse_exemptions;
+
+  ASSERT_THAT(name_collapse_exemptions.size(), Eq(2));
+  EXPECT_THAT(name_collapse_exemptions, Contains(ResourceName({}, ResourceType::kString, "foo")));
+  EXPECT_THAT(name_collapse_exemptions, Contains(ResourceName({}, ResourceType::kDimen, "bar")));
+}
+
+TEST_F(OptimizeTest, ParseConfigWithNoObfuscateExemptions) {
+  const std::string& content = R"(
+string/foo#no_obfuscate
+dimen/bar#no_obfuscate
+)";
+  aapt::test::Context context;
+  OptimizeOptions options;
+  ParseConfig(content, &context, &options);
+
+  const std::set<ResourceName>& name_collapse_exemptions =
+      options.table_flattener_options.name_collapse_exemptions;
+
+  ASSERT_THAT(name_collapse_exemptions.size(), Eq(2));
+  EXPECT_THAT(name_collapse_exemptions, Contains(ResourceName({}, ResourceType::kString, "foo")));
+  EXPECT_THAT(name_collapse_exemptions, Contains(ResourceName({}, ResourceType::kDimen, "bar")));
+}
+
+}  // namespace aapt
diff --git a/tools/aapt2/cmd/Util.cpp b/tools/aapt2/cmd/Util.cpp
index e2c65ba74271..7214f1a68d2c 100644
--- a/tools/aapt2/cmd/Util.cpp
+++ b/tools/aapt2/cmd/Util.cpp
@@ -436,9 +436,9 @@ void SetLongVersionCode(xml::Element* manifest, uint64_t version) {
 }
 
 std::regex GetRegularExpression(const std::string &input) {
-  // Standard ECMAScript grammar plus case insensitive.
+  // Standard ECMAScript grammar.
   std::regex case_insensitive(
-      input, std::regex_constants::icase | std::regex_constants::ECMAScript);
+      input, std::regex_constants::ECMAScript);
   return case_insensitive;
 }
 
diff --git a/tools/aapt2/cmd/Util_test.cpp b/tools/aapt2/cmd/Util_test.cpp
index 7e492610b658..ac1f981d753c 100644
--- a/tools/aapt2/cmd/Util_test.cpp
+++ b/tools/aapt2/cmd/Util_test.cpp
@@ -383,7 +383,7 @@ TEST (UtilTest, AdjustSplitConstraintsForMinSdk) {
   EXPECT_NE(*adjusted_contraints[1].configs.begin(), ConfigDescription::DefaultConfig());
 }
 
-TEST(UtilTest, RegularExperssions) {
+TEST (UtilTest, RegularExperssionsSimple) {
   std::string valid(".bc$");
   std::regex expression = GetRegularExpression(valid);
   EXPECT_TRUE(std::regex_search("file.abc", expression));
@@ -391,4 +391,24 @@ TEST(UtilTest, RegularExperssions) {
   EXPECT_FALSE(std::regex_search("abc.zip", expression));
 }
 
+TEST (UtilTest, RegularExpressionComplex) {
+  std::string valid("\\.(d|D)(e|E)(x|X)$");
+  std::regex expression = GetRegularExpression(valid);
+  EXPECT_TRUE(std::regex_search("file.dex", expression));
+  EXPECT_TRUE(std::regex_search("file.DEX", expression));
+  EXPECT_TRUE(std::regex_search("file.dEx", expression));
+  EXPECT_FALSE(std::regex_search("file.dexx", expression));
+  EXPECT_FALSE(std::regex_search("dex.file", expression));
+  EXPECT_FALSE(std::regex_search("file.adex", expression));
+}
+
+TEST (UtilTest, RegularExpressionNonEnglish) {
+  std::string valid("\\.(k|K)(o|O)(ń|Ń)(c|C)(ó|Ó)(w|W)(k|K)(a|A)$");
+  std::regex expression = GetRegularExpression(valid);
+  EXPECT_TRUE(std::regex_search("file.końcówka", expression));
+  EXPECT_TRUE(std::regex_search("file.KOŃCÓWKA", expression));
+  EXPECT_TRUE(std::regex_search("file.kOńcÓwkA", expression));
+  EXPECT_FALSE(std::regex_search("file.koncowka", expression));
+}
+
 }  // namespace aapt