WIP, not for submit: benchmark analyzer-based generation

_test/bin/benchmark.dart

@@ -0,0 +1,71 @@
+import 'dart:io';
+
+import '../test/common/utils.dart';
+
+Future<void> main() async {
+  // only works in test
+  inTest = false;
+  ensureCleanGitClient();
+  print('Initial build.');
+  await runBuild();
+  print('Done.');
+
+  print('Files,Build time/ms,Incremental time/ms');
+  for (final size in [
+    100,
+    500,
+    1000,
+    1500,
+    2000,
+    2500,
+    3000,
+    3500,
+    4000,
+    4500,
+    5000,
+  ]) {
+    stdout.write('$size,');
+
+    await createFile(
+      'lib/bv_app.dart',
+      [
+        for (var i = 0; i != size; ++i) "import 'built_value${i + 1}.dart';",
+      ].join('\n'),
+    );
+
+    for (var i = 0; i != size; ++i) {
+      await createFile('lib/built_value${i + 1}.dart', '''
+import 'package:built_value/built_value.dart';
+
+import 'bv_app.dart';
+
+part 'built_value${i + 1}.g.dart';
+
+abstract class Value implements Built<Value, ValueBuilder> {
+  Value._();
+  factory Value([void Function(ValueBuilder)? updates]) = _\$Value;
+}
+''');
+    }
+    final stopwatch = Stopwatch()..start();
+    await runBuild();
+    stdout.write('${stopwatch.elapsedMilliseconds},');
+
+    await createFile('lib/built_value1.dart', '''
+import 'package:built_value/built_value.dart';
+
+import 'bv_app.dart';
+
+part 'built_value1.g.dart';
+
+abstract class Value implements Built<Value, ValueBuilder> {
+  int get x;
+  Value._();
+  factory Value([void Function(ValueBuilder)? updates]) = _\$Value;
+}
+''');
+    stopwatch.reset();
+    await runBuild();
+    print(stopwatch.elapsedMilliseconds);
+  }
+}

_test/lib/built_value1.dart

@@ -0,0 +1,10 @@
+import 'package:built_value/built_value.dart';
+
+
+
+part 'built_value1.g.dart';
+
+abstract class Value implements Built<Value, ValueBuilder> {
+  Value._();
+  factory Value([void Function(ValueBuilder)? updates]) = _$Value;
+}

_test/pubspec.yaml

@@ -6,6 +6,7 @@ environment:
   sdk: ^3.6.0
 
 dependencies:
+  built_value: ^8.9.0
   web: ^1.0.0
 
 dev_dependencies:
@@ -18,6 +19,7 @@ dev_dependencies:
   build_runner_core: any
   build_test: any
   build_web_compilers: any
+  built_value_generator: ^8.9.0
   dart_flutter_team_lints: ^3.1.0
   io: ^1.0.0
   path: ^1.8.0