Generate DAO classes

sally/lib/src/runtime/database.dart

@@ -11,9 +11,13 @@ import 'package:sally/src/runtime/statements/update.dart';
 /// This comes in handy to structure large amounts of database code better: The
 /// migration logic can live in the main [GeneratedDatabase] class, but code
 /// can be extracted into [DatabaseAccessor]s outside of that database.
-abstract class DatabaseAccessor extends DatabaseConnectionUser
+abstract class DatabaseAccessor<T extends GeneratedDatabase> extends DatabaseConnectionUser
     with QueryEngine {
-  DatabaseAccessor(GeneratedDatabase db) : super.delegate(db);
+
+  @protected
+  final T db;
+
+  DatabaseAccessor(this.db) : super.delegate(db);
 }
 
 /// Mediocre class name for something that manages a typesystem to map between

sally_flutter/example/lib/database/database.g.dart

@@ -43,9 +43,9 @@ class TodoEntry {
           other.category == category);
 }
 
-class _$TodosTable extends Todos implements TableInfo<Todos, TodoEntry> {
+class $TodosTable extends Todos implements TableInfo<Todos, TodoEntry> {
   final GeneratedDatabase _db;
-  _$TodosTable(this._db);
+  $TodosTable(this._db);
   @override
   GeneratedIntColumn get id =>
       GeneratedIntColumn('id', false, hasAutoIncrement: true);
@@ -132,10 +132,10 @@ class Category {
       (other is Category && other.id == id && other.description == description);
 }
 
-class _$CategoriesTable extends Categories
+class $CategoriesTable extends Categories
     implements TableInfo<Categories, Category> {
   final GeneratedDatabase _db;
-  _$CategoriesTable(this._db);
+  $CategoriesTable(this._db);
   @override
   GeneratedIntColumn get id =>
       GeneratedIntColumn('id', false, hasAutoIncrement: true);
@@ -176,10 +176,10 @@ class _$CategoriesTable extends Categories
 
 abstract class _$Database extends GeneratedDatabase {
   _$Database(QueryExecutor e) : super(const SqlTypeSystem.withDefaults(), e);
-  _$TodosTable get todos => _$TodosTable(this);
-  _$CategoriesTable get categories => _$CategoriesTable(this);
+  $TodosTable get todos => $TodosTable(this);
+  $CategoriesTable get categories => $CategoriesTable(this);
   TodosDao _todosDao;
-  TodosDao get todosDao => _todosDao ??= TodosDao(this);
+  TodosDao get todosDao => _todosDao ??= TodosDao(this as Database);
   @override
   List<TableInfo> get allTables => [todos, categories];
 }

sally_flutter/example/lib/database/todos_dao.dart

@@ -3,9 +3,11 @@ import 'dart:async';
 import 'package:sally/sally.dart';
 import 'database.dart';
 
+part 'todos_dao.g.dart';
+
 @UseDao(tables: [Todos])
-class TodosDao extends DatabaseAccessor {
-  TodosDao(GeneratedDatabase db) : super(db);
+class TodosDao extends DatabaseAccessor<Database> with _TodosDaoMixin {
+  TodosDao(Database db) : super(db);
 
   Stream<List<TodoEntry>> todosWithoutCategory() {
     return null;

sally_flutter/example/lib/database/todos_dao.g.dart

@@ -0,0 +1,11 @@
+// GENERATED CODE - DO NOT MODIFY BY HAND
+
+part of 'todos_dao.dart';
+
+// **************************************************************************
+// DaoGenerator
+// **************************************************************************
+
+mixin _TodosDaoMixin on DatabaseAccessor<Database> {
+  $TodosTable get todos => db.todos;
+}

sally_generator/lib/generator.dart

@@ -1,6 +1,7 @@
 import 'package:build/build.dart';
+import 'package:sally_generator/src/dao_generator.dart';
 import 'package:source_gen/source_gen.dart';
 import 'package:sally_generator/src/sally_generator.dart';
 
 Builder sallyBuilder(BuilderOptions _) =>
-    SharedPartBuilder([SallyGenerator()], 'sally');
+    SharedPartBuilder([SallyGenerator(), DaoGenerator()], 'sally');

sally_generator/lib/src/dao_generator.dart

@@ -0,0 +1,58 @@
+import 'package:analyzer/dart/element/element.dart';
+import 'package:build/build.dart';
+import 'package:recase/recase.dart';
+import 'package:sally/sally.dart';
+import 'package:sally_generator/src/model/specified_table.dart';
+import 'package:source_gen/source_gen.dart';
+
+class DaoGenerator extends GeneratorForAnnotation<UseDao> {
+  @override
+  generateForAnnotatedElement(
+      Element element, ConstantReader annotation, BuildStep buildStep) {
+    final tableTypes =
+        annotation.peek('tables').listValue.map((obj) => obj.toTypeValue());
+
+    if (element is! ClassElement) {
+      throw InvalidGenerationSourceError(
+          'This annotation can only be used on classes',
+          element: element);
+    }
+
+    final enclosingClass = element as ClassElement;
+
+    final dbType = enclosingClass.supertype;
+    if (dbType.name != 'DatabaseAccessor') {
+      throw InvalidGenerationSourceError(
+          'This class must directly inherit from DatabaseAccessor',
+          element: element);
+    }
+
+    // inherits from DatabaseAccessor<T>, we want to know which T
+    final dbImpl = dbType.typeArguments.single;
+    if (dbImpl.isDynamic) {
+      throw InvalidGenerationSourceError(
+          'This class must inherit from DatabaseAccessor<T>, where T is an '
+          'actual type of a database.',
+          element: element);
+    }
+
+    // finally, we can write the mixin
+    final buffer = StringBuffer();
+
+    final daoName = enclosingClass.displayName;
+
+    buffer.write('mixin _${daoName}Mixin on '
+        'DatabaseAccessor<${dbImpl.displayName}> {\n');
+
+    for (var table in tableTypes) {
+      final infoType = tableInfoNameForTableClass(table.element as ClassElement);
+      final getterName = ReCase(table.name).camelCase;
+
+      buffer.write('$infoType get $getterName => db.$getterName;\n');
+    }
+
+    buffer.write('}');
+
+    return buffer.toString();
+  }
+}

sally_generator/lib/src/model/specified_table.dart

@@ -9,7 +9,7 @@ class SpecifiedTable {
   /// The name for the data class associated with this table
   final String dartTypeName;
 
-  String get tableInfoName => '_\$${fromClass.name}Table';
+  String get tableInfoName => tableInfoNameForTableClass(fromClass);
 
   // todo support primary keys
   Set<SpecifiedColumn> get primaryKey => <SpecifiedColumn>{};
@@ -17,3 +17,5 @@ class SpecifiedTable {
   const SpecifiedTable(
       {this.fromClass, this.columns, this.sqlName, this.dartTypeName});
 }
+
+String tableInfoNameForTableClass(ClassElement fromClass) => '\$${fromClass.name}Table';

sally_generator/lib/src/writer/database_writer.dart

@@ -39,9 +39,12 @@ class DatabaseWriter {
       final getterName = ReCase(typeName).camelCase;
       final fieldName = '_$getterName';
 
+      final databaseImplName = db.fromClass.name;
+
       buffer
         ..write('$typeName $fieldName;\n')
-        ..write('$typeName get $getterName => $fieldName ??= $typeName(this);');
+        ..write('$typeName get $getterName => $fieldName ??= '
+            '$typeName(this as $databaseImplName);');
     }
 
     // Write List of tables, close bracket for class