address comments

pkgs/native_assets_builder/lib/src/build_runner/build_runner.dart

@@ -23,15 +23,22 @@ import 'build_planner.dart';
 
 typedef DependencyMetadata = Map<String, Metadata>;
 
-typedef HookValidator = Future<ValidationErrors> Function(
+typedef _HookValidator = Future<ValidationErrors> Function(
     HookConfig config, HookOutputImpl output);
 
+// A callback that validates the output of a `hook/link.dart` invocation is
+// valid (it may valid asset-type specific information).
 typedef BuildValidator = Future<ValidationErrors> Function(
     BuildConfig config, BuildOutput outup);
 
+// A callback that validates the output of a `hook/link.dart` invocation is
+// valid (it may valid asset-type specific information).
 typedef LinkValidator = Future<ValidationErrors> Function(
     LinkConfig config, LinkOutput output);
 
+// A callback that validates assets emitted across all packages are valid / can
+// be used together (it may valid asset-type specific information - e.g. that
+// there are no classes in shared library filenames).
 typedef ApplicationAssetValidator = Future<ValidationErrors> Function(
     List<EncodedAsset> assets);
 
@@ -165,7 +172,7 @@ class NativeAssetsBuildRunner {
     required Target target,
     required Uri workingDirectory,
     required BuildMode buildMode,
-    required HookValidator validator,
+    required _HookValidator validator,
     required ApplicationAssetValidator applicationAssetValidator,
     CCompilerConfig? cCompilerConfig,
     IOSSdk? targetIOSSdk,
@@ -466,7 +473,7 @@ class NativeAssetsBuildRunner {
   Future<_PackageBuildRecord> _runHookForPackageCached(
     Hook hook,
     HookConfigImpl config,
-    HookValidator validator,
+    _HookValidator validator,
     Uri packageConfigUri,
     Uri workingDirectory,
     bool includeParentEnvironment,
@@ -535,7 +542,7 @@ class NativeAssetsBuildRunner {
   Future<_PackageBuildRecord> _runHookForPackage(
     Hook hook,
     HookConfigImpl config,
-    HookValidator validator,
+    _HookValidator validator,
     Uri packageConfigUri,
     Uri workingDirectory,
     bool includeParentEnvironment,
@@ -595,7 +602,7 @@ ${result.stdout}
       final output = HookOutputImpl.readFromFile(file: config.outputFile) ??
           HookOutputImpl();
 
-      final errors = await validate(config, output, packageLayout, validator);
+      final errors = await _validate(config, output, packageLayout, validator);
       success &= errors.isEmpty;
       if (errors.isNotEmpty) {
         logger.severe('package:${config.packageName}` has invalid output.');
@@ -804,11 +811,11 @@ ${compileResult.stdout}
     };
   }
 
-  Future<ValidationErrors> validate(
+  Future<ValidationErrors> _validate(
     HookConfigImpl config,
     HookOutputImpl output,
     PackageLayout packageLayout,
-    HookValidator validator,
+    _HookValidator validator,
   ) async {
     final errors = config is BuildConfigImpl
         ? await validateBuildOutput(config, output)

pkgs/native_assets_cli/example/link/package_with_assets/hook/build.dart

@@ -24,12 +24,12 @@ void main(List<String> args) async {
           .toFilePath(windows: false)
           .substring(config.packageRoot.toFilePath(windows: false).length);
 
-      output.addEncodedAsset(
+      output.dataAssets.add(
         DataAsset(
           package: packageName,
           name: name,
           file: dataAsset.uri,
-        ).encode(),
+        ),
         linkInPackage: config.linkingEnabled ? packageName : null,
       );
       // TODO(https://github.com/dart-lang/native/issues/1208): Report

pkgs/native_assets_cli/example/link/package_with_assets/hook/link.dart

@@ -20,10 +20,8 @@ void main(List<String> args) async {
     final usedAssets = (usages.instancesOf(multiplyIdentifier) ?? []).map((e) =>
         (e.instanceConstant.fields.values.first as StringConstant).value);
 
-    output.addEncodedAssets(config.encodedAssets
-        .where((e) => e.type == DataAsset.type)
-        .where(
-            (asset) => usedAssets.contains(DataAsset.fromEncoded(asset).name)));
+    output.dataAssets.addAll(config.dataAssets.all
+        .where((dataAsset) => usedAssets.contains(dataAsset.name)));
   });
 }
 

pkgs/native_assets_cli/lib/native_assets_cli.dart

@@ -21,19 +21,19 @@ export 'src/code_assets/code_asset.dart'
     show
         BuildOutputCodeAssets,
         CodeAsset,
-        CodeAssetsBuildOutputExt,
-        CodeAssetsLinkConfigExt,
-        CodeAssetsLinkOutputExt,
+        CodeAssetsBuildOutput,
+        CodeAssetsLinkConfig,
+        CodeAssetsLinkOutput,
         LinkConfigCodeAssets,
         LinkOutputCodeAssets,
         OSLibraryNaming;
 export 'src/data_assets/data_asset.dart'
     show
         BuildOutputDataAssets,
         DataAsset,
-        DataAssetsBuildOutputExt,
-        DataAssetsLinkConfigExt,
-        DataAssetsLinkOutputExt,
+        DataAssetsBuildOutput,
+        DataAssetsLinkConfig,
+        DataAssetsLinkOutput,
         LinkConfigDataAssets,
         LinkOutputDataAssets;
 export 'src/encoded_asset.dart' show EncodedAsset;

pkgs/native_assets_cli/lib/src/api/build.dart

@@ -70,7 +70,7 @@ import 'build_output.dart';
 ///       ]);
 ///     }
 ///
-///     output.addEncodedAsset(
+///     output.codeAssets.add(
 ///       // TODO: Change to DataAsset once the Dart/Flutter SDK can consume it.
 ///       CodeAsset(
 ///         package: packageName,

pkgs/native_assets_cli/lib/src/api/build_output.dart

@@ -116,6 +116,18 @@ abstract final class BuildOutput {
   /// If the [linkInPackage] argument is specified, the asset will not be
   /// bundled during the build step, but sent as input to the link hook of the
   /// specified package, where it can be further processed and possibly bundled.
+  ///
+  /// Note to hook writers. Prefer using the `.add` method on the extension for
+  /// the specific asset type being added:
+  ///
+  /// ```dart
+  /// main(List<String> arguments) async {
+  ///   await build((config, output) {
+  ///     output.codeAssets.add(CodeAsset(...));
+  ///     output.dataAssets.add(DataAsset(...));
+  ///   });
+  /// }
+  /// ```
   void addEncodedAsset(EncodedAsset asset, {String? linkInPackage});
 
   /// Adds [EncodedAsset]s produced by this build or dry run.
@@ -124,6 +136,18 @@ abstract final class BuildOutput {
   /// bundled during the build step, but sent as input to the link hook of the
   /// specified package, where they can be further processed and possibly
   /// bundled.
+  ///
+  /// Note to hook writers. Prefer using the `.addAll` method on the extension
+  /// for the specific asset type being added:
+  ///
+  /// ```dart
+  /// main(List<String> arguments) async {
+  ///   await build((config, output) {
+  ///     output.codeAssets.addAll([CodeAsset(...), ...]);
+  ///     output.dataAssets.addAll([DataAsset(...), ...]);
+  ///   });
+  /// }
+  /// ```
   void addEncodedAssets(Iterable<EncodedAsset> assets, {String? linkInPackage});
 
   /// Adds file used by this build.

pkgs/native_assets_cli/lib/src/api/test.dart

@@ -70,7 +70,7 @@ Future<void> testBuildHook({
 
       await mainMethod(['--config=${buildConfigUri.toFilePath()}']);
 
-      final hookOutput = await _readOutput(buildConfig);
+      final hookOutput = await _readOutput(buildConfig) as BuildOutput;
 
       check(buildConfig, hookOutput);
 
@@ -81,19 +81,12 @@ Future<void> testBuildHook({
       for (final asset in allEncodedAssets) {
         expect(buildConfig.supportedAssetTypes, contains(asset.type));
       }
-      final dataAssets = allEncodedAssets
-          .where((e) => e.type == DataAsset.type)
-          .map(DataAsset.fromEncoded)
-          .toList();
-      for (final asset in dataAssets) {
+
+      for (final asset in hookOutput.dataAssets.all) {
         final file = File.fromUri(asset.file);
         expect(await file.exists(), true);
       }
-      final codeAssets = allEncodedAssets
-          .where((e) => e.type == CodeAsset.type)
-          .map(CodeAsset.fromEncoded)
-          .toList();
-      for (final asset in codeAssets) {
+      for (final asset in hookOutput.codeAssets.all) {
         if (asset.file != null) {
           final file = File.fromUri(asset.file!);
           expect(await file.exists(), true);

pkgs/native_assets_cli/lib/src/code_assets/code_asset.dart

@@ -191,7 +191,7 @@ final class CodeAsset {
 }
 
 /// Build output extension for code assets.
-extension CodeAssetsBuildOutputExt on BuildOutput {
+extension CodeAssetsBuildOutput on BuildOutput {
   BuildOutputCodeAssets get codeAssets => BuildOutputCodeAssets(this);
 }
 
@@ -215,7 +215,7 @@ class BuildOutputCodeAssets {
 }
 
 /// Link output extension for code assets.
-extension CodeAssetsLinkConfigExt on LinkConfig {
+extension CodeAssetsLinkConfig on LinkConfig {
   LinkConfigCodeAssets get codeAssets => LinkConfigCodeAssets(this);
 }
 
@@ -230,7 +230,7 @@ class LinkConfigCodeAssets {
 }
 
 /// Link output extension for code assets.
-extension CodeAssetsLinkOutputExt on LinkOutput {
+extension CodeAssetsLinkOutput on LinkOutput {
   LinkOutputCodeAssets get codeAssets => LinkOutputCodeAssets(this);
 }
 

pkgs/native_assets_cli/lib/src/data_assets/data_asset.dart

@@ -93,7 +93,7 @@ final class DataAsset {
 }
 
 /// Build output extension for data assets.
-extension DataAssetsBuildOutputExt on BuildOutput {
+extension DataAssetsBuildOutput on BuildOutput {
   BuildOutputDataAssets get dataAssets => BuildOutputDataAssets(this);
 }
 
@@ -117,7 +117,7 @@ class BuildOutputDataAssets {
 }
 
 /// Link output extension for data assets.
-extension DataAssetsLinkConfigExt on LinkConfig {
+extension DataAssetsLinkConfig on LinkConfig {
   LinkConfigDataAssets get dataAssets => LinkConfigDataAssets(this);
 }
 
@@ -132,7 +132,7 @@ class LinkConfigDataAssets {
 }
 
 /// Link output extension for data assets.
-extension DataAssetsLinkOutputExt on LinkOutput {
+extension DataAssetsLinkOutput on LinkOutput {
   LinkOutputDataAssets get dataAssets => LinkOutputDataAssets(this);
 }
 

pkgs/native_assets_cli/lib/src/encoded_asset.dart

@@ -5,6 +5,7 @@
 import 'package:collection/collection.dart';
 
 import 'json_utils.dart';
+import 'utils/map.dart';
 
 /// An encoding of a particular asset type.
 final class EncodedAsset {
@@ -27,7 +28,7 @@ final class EncodedAsset {
   Map<String, Object?> toJson() => {
         for (final key in encoding.keys) key: encoding[key],
         _typeKey: type,
-      };
+      }..sortOnKey();
 
   @override
   String toString() => 'EncodedAsset($type, $encoding)';

pkgs/native_assets_cli/lib/src/utils/map.dart

@@ -2,13 +2,12 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-extension MapSorting<K extends Comparable<K>, V extends Object> on Map<K, V> {
+extension MapSorting<K extends Comparable<K>, V extends Object?> on Map<K, V> {
   Map<K, V> sortOnKey() {
     final result = <K, V>{};
     final keysSorted = keys.toList()..sort();
     for (final key in keysSorted) {
-      final value = this[key]!;
-      result[key] = value;
+      result[key] = this[key] as V;
     }
     return result;
   }

pkgs/native_assets_cli/test/example/local_asset_test.dart

@@ -77,14 +77,12 @@ void main() async {
 
       final buildOutputUri = outputDirectory.resolve('build_output.json');
       final buildOutput = HookOutputImpl.fromJsonString(
-          await File.fromUri(buildOutputUri).readAsString());
+          await File.fromUri(buildOutputUri).readAsString()) as BuildOutput;
       final assets = buildOutput.encodedAssets;
       final dependencies = buildOutput.dependencies;
       if (dryRun) {
+        final codeAsset = buildOutput.codeAssets.all.first;
         expect(assets.length, greaterThanOrEqualTo(1));
-        final first = assets.first;
-        expect(first.type, CodeAsset.type);
-        final codeAsset = CodeAsset.fromEncoded(first);
         expect(await File.fromUri(codeAsset.file!).exists(), false);
         expect(dependencies, <Uri>[]);
       } else {

pkgs/native_assets_cli/test/model/link_config_test.dart

@@ -35,7 +35,7 @@ void main() async {
       file: Uri.file('not there'),
       architecture: Architecture.riscv64,
     ).encode(),
-  ].cast<EncodedAsset>();
+  ];
 
   setUp(() async {
     tempUri = (await Directory.systemTemp.createTemp()).uri;