starting implement inject generator

cherrypick_generator/lib/inject_generator.dart

@@ -0,0 +1,65 @@
+import 'dart:async';
+import 'package:build/build.dart';
+import 'package:collection/collection.dart';
+import 'package:source_gen/source_gen.dart';
+import 'package:analyzer/dart/element/element.dart';
+import 'package:cherrypick_annotations/cherrypick_annotations.dart' as ann;
+
+class InjectGenerator extends GeneratorForAnnotation<ann.injectable> {
+  const InjectGenerator();
+
+  @override
+  FutureOr<String> generateForAnnotatedElement(
+      Element element, ConstantReader annotation, BuildStep buildStep) {
+    // Only classes are supported for @module() annotation
+    // Обрабатываются только классы (другие элементы — ошибка)
+    if (element is! ClassElement) {
+      throw InvalidGenerationSourceError(
+        '@injectable() can only be applied to classes.',
+        element: element,
+      );
+    }
+
+    final classElement = element;
+    final className = classElement.name;
+    final mixinName = '_\$$className';
+
+    final injectedFields = classElement.fields.where((field) => field.metadata
+        .any((m) =>
+            m.computeConstantValue()?.type?.getDisplayString() == 'inject'));
+
+    // Генерируем инициализацию для каждого поля с аннотацией @inject()
+    final buffer = StringBuffer();
+    buffer.writeln('mixin $mixinName {');
+    buffer.writeln('  void _inject($className instance) {');
+
+    for (final field in injectedFields) {
+      // Получаем имя типа
+      final fieldType = field.type.getDisplayString();
+      // Ищем аннотацию @named
+      final namedAnnotation = field.metadata.firstWhereOrNull(
+        (m) => m.computeConstantValue()?.type?.getDisplayString() == 'named',
+      );
+      String namedParam = '';
+      if (namedAnnotation != null) {
+        final namedValue = namedAnnotation
+            .computeConstantValue()
+            ?.getField('value')
+            ?.toStringValue();
+        if (namedValue != null) {
+          namedParam = "(named: '$namedValue')";
+        }
+      }
+      buffer.writeln(
+          "    instance.${field.name} = CherryPick.openRootScope().resolve<$fieldType>$namedParam;");
+    }
+
+    buffer.writeln('  }');
+    buffer.writeln('}');
+
+    return buffer.toString();
+  }
+}
+
+Builder injectBuilder(BuilderOptions options) =>
+    PartBuilder([InjectGenerator()], '.inject.cherrypick.g.dart');