Memoized getters for generated classes

.travis.yml

@@ -13,6 +13,7 @@ script: ./tool/mono_repo_wrapper.sh
 branches:
   only:
     - master
+    - develop
 
 cache:
   directories:

moor/example/example.g.dart

@@ -43,11 +43,13 @@ class $CategoriesTable extends Categories
     implements TableInfo<Categories, Category> {
   final GeneratedDatabase _db;
   $CategoriesTable(this._db);
+  GeneratedIntColumn _id;
   @override
   GeneratedIntColumn get id =>
-      GeneratedIntColumn('id', false, hasAutoIncrement: true);
+      _id ??= GeneratedIntColumn('id', false, hasAutoIncrement: true);
+  GeneratedTextColumn _description;
   @override
-  GeneratedTextColumn get description => GeneratedTextColumn(
+  GeneratedTextColumn get description => _description ??= GeneratedTextColumn(
         'description',
         true,
       );
@@ -133,19 +135,23 @@ class Recipe {
 class $RecipesTable extends Recipes implements TableInfo<Recipes, Recipe> {
   final GeneratedDatabase _db;
   $RecipesTable(this._db);
+  GeneratedIntColumn _id;
   @override
   GeneratedIntColumn get id =>
-      GeneratedIntColumn('id', false, hasAutoIncrement: true);
+      _id ??= GeneratedIntColumn('id', false, hasAutoIncrement: true);
+  GeneratedTextColumn _title;
   @override
   GeneratedTextColumn get title =>
-      GeneratedTextColumn('title', false, maxTextLength: 16);
+      _title ??= GeneratedTextColumn('title', false, maxTextLength: 16);
+  GeneratedTextColumn _instructions;
   @override
-  GeneratedTextColumn get instructions => GeneratedTextColumn(
+  GeneratedTextColumn get instructions => _instructions ??= GeneratedTextColumn(
         'instructions',
         false,
       );
+  GeneratedIntColumn _category;
   @override
-  GeneratedIntColumn get category => GeneratedIntColumn(
+  GeneratedIntColumn get category => _category ??= GeneratedIntColumn(
         'category',
         true,
       );
@@ -232,16 +238,20 @@ class $IngredientsTable extends Ingredients
     implements TableInfo<Ingredients, Ingredient> {
   final GeneratedDatabase _db;
   $IngredientsTable(this._db);
+  GeneratedIntColumn _id;
   @override
   GeneratedIntColumn get id =>
-      GeneratedIntColumn('id', false, hasAutoIncrement: true);
+      _id ??= GeneratedIntColumn('id', false, hasAutoIncrement: true);
+  GeneratedTextColumn _name;
   @override
-  GeneratedTextColumn get name => GeneratedTextColumn(
+  GeneratedTextColumn get name => _name ??= GeneratedTextColumn(
         'name',
         false,
       );
+  GeneratedIntColumn _caloriesPer100g;
   @override
-  GeneratedIntColumn get caloriesPer100g => GeneratedIntColumn(
+  GeneratedIntColumn get caloriesPer100g =>
+      _caloriesPer100g ??= GeneratedIntColumn(
         'calories',
         false,
       );
@@ -327,18 +337,21 @@ class $IngredientInRecipesTable extends IngredientInRecipes
     implements TableInfo<IngredientInRecipes, IngredientInRecipe> {
   final GeneratedDatabase _db;
   $IngredientInRecipesTable(this._db);
+  GeneratedIntColumn _recipe;
   @override
-  GeneratedIntColumn get recipe => GeneratedIntColumn(
+  GeneratedIntColumn get recipe => _recipe ??= GeneratedIntColumn(
         'recipe',
         false,
       );
+  GeneratedIntColumn _ingredient;
   @override
-  GeneratedIntColumn get ingredient => GeneratedIntColumn(
+  GeneratedIntColumn get ingredient => _ingredient ??= GeneratedIntColumn(
         'ingredient',
         false,
       );
+  GeneratedIntColumn _amountInGrams;
   @override
-  GeneratedIntColumn get amountInGrams => GeneratedIntColumn(
+  GeneratedIntColumn get amountInGrams => _amountInGrams ??= GeneratedIntColumn(
         'amount',
         false,
       );
@@ -379,11 +392,15 @@ class $IngredientInRecipesTable extends IngredientInRecipes
 
 abstract class _$Database extends GeneratedDatabase {
   _$Database(QueryExecutor e) : super(const SqlTypeSystem.withDefaults(), e);
-  $CategoriesTable get categories => $CategoriesTable(this);
+  $CategoriesTable _categories;
-  $RecipesTable get recipes => $RecipesTable(this);
+  $CategoriesTable get categories => _categories ??= $CategoriesTable(this);
-  $IngredientsTable get ingredients => $IngredientsTable(this);
+  $RecipesTable _recipes;
+  $RecipesTable get recipes => _recipes ??= $RecipesTable(this);
+  $IngredientsTable _ingredients;
+  $IngredientsTable get ingredients => _ingredients ??= $IngredientsTable(this);
+  $IngredientInRecipesTable _ingredientInRecipes;
   $IngredientInRecipesTable get ingredientInRecipes =>
-      $IngredientInRecipesTable(this);
+      _ingredientInRecipes ??= $IngredientInRecipesTable(this);
   @override
   List<TableInfo> get allTables =>
       [categories, recipes, ingredients, ingredientInRecipes];

moor/lib/src/dsl/columns.dart

@@ -60,6 +60,7 @@ class IntColumnBuilder extends ColumnBuilder<IntColumnBuilder, IntColumn> {
 }
 
 class BoolColumnBuilder extends ColumnBuilder<BoolColumnBuilder, BoolColumn> {}
+
 class BlobColumnBuilder extends ColumnBuilder<BlobColumnBuilder, BlobColumn> {}
 
 class TextColumnBuilder extends ColumnBuilder<TextColumnBuilder, TextColumn> {

moor/lib/src/types/sql_types.dart

@@ -98,7 +98,6 @@ class DateTimeType extends SqlType<DateTime> {
 }
 
 class BlobType extends SqlType<Uint8List> {
-
   const BlobType();
 
   @override
@@ -111,5 +110,4 @@ class BlobType extends SqlType<Uint8List> {
 
   @override
   mapToSqlVariable(content) => content;
-
+}
-}

moor/lib/src/types/type_system.dart

@@ -8,7 +8,13 @@ class SqlTypeSystem {
   const SqlTypeSystem(this.types);
 
   const SqlTypeSystem.withDefaults()
-      : this(const [BoolType(), StringType(), IntType(), DateTimeType(), BlobType()]);
+      : this(const [
+          BoolType(),
+          StringType(),
+          IntType(),
+          DateTimeType(),
+          BlobType()
+        ]);
 
   /// Returns the appropriate sql type for the dart type provided as the
   /// generic parameter.

moor/test/data/tables/todos.g.dart

@@ -72,24 +72,30 @@ class $TodosTableTable extends TodosTable
     implements TableInfo<TodosTable, TodoEntry> {
   final GeneratedDatabase _db;
   $TodosTableTable(this._db);
+  GeneratedIntColumn _id;
   @override
   GeneratedIntColumn get id =>
-      GeneratedIntColumn('id', false, hasAutoIncrement: true);
+      _id ??= GeneratedIntColumn('id', false, hasAutoIncrement: true);
+  GeneratedTextColumn _title;
   @override
-  GeneratedTextColumn get title =>
+  GeneratedTextColumn get title => _title ??=
       GeneratedTextColumn('title', true, minTextLength: 4, maxTextLength: 16);
+  GeneratedTextColumn _content;
   @override
-  GeneratedTextColumn get content => GeneratedTextColumn(
+  GeneratedTextColumn get content => _content ??= GeneratedTextColumn(
         'content',
         false,
       );
+  GeneratedDateTimeColumn _targetDate;
   @override
-  GeneratedDateTimeColumn get targetDate => GeneratedDateTimeColumn(
+  GeneratedDateTimeColumn get targetDate =>
+      _targetDate ??= GeneratedDateTimeColumn(
         'target_date',
         true,
       );
+  GeneratedIntColumn _category;
   @override
-  GeneratedIntColumn get category => GeneratedIntColumn(
+  GeneratedIntColumn get category => _category ??= GeneratedIntColumn(
         'category',
         true,
       );
@@ -173,11 +179,13 @@ class $CategoriesTable extends Categories
     implements TableInfo<Categories, Category> {
   final GeneratedDatabase _db;
   $CategoriesTable(this._db);
+  GeneratedIntColumn _id;
   @override
   GeneratedIntColumn get id =>
-      GeneratedIntColumn('id', false, hasAutoIncrement: true);
+      _id ??= GeneratedIntColumn('id', false, hasAutoIncrement: true);
+  GeneratedTextColumn _description;
   @override
-  GeneratedTextColumn get description => GeneratedTextColumn(
+  GeneratedTextColumn get description => _description ??= GeneratedTextColumn(
         '`desc`',
         false,
       );
@@ -266,19 +274,24 @@ class User {
 class $UsersTable extends Users implements TableInfo<Users, User> {
   final GeneratedDatabase _db;
   $UsersTable(this._db);
+  GeneratedIntColumn _id;
   @override
   GeneratedIntColumn get id =>
-      GeneratedIntColumn('id', false, hasAutoIncrement: true);
+      _id ??= GeneratedIntColumn('id', false, hasAutoIncrement: true);
+  GeneratedTextColumn _name;
   @override
-  GeneratedTextColumn get name =>
+  GeneratedTextColumn get name => _name ??=
       GeneratedTextColumn('name', false, minTextLength: 6, maxTextLength: 32);
+  GeneratedBoolColumn _isAwesome;
   @override
-  GeneratedBoolColumn get isAwesome => GeneratedBoolColumn(
+  GeneratedBoolColumn get isAwesome => _isAwesome ??= GeneratedBoolColumn(
         'is_awesome',
         false,
       );
+  GeneratedBlobColumn _profilePicture;
   @override
-  GeneratedBlobColumn get profilePicture => GeneratedBlobColumn(
+  GeneratedBlobColumn get profilePicture =>
+      _profilePicture ??= GeneratedBlobColumn(
         'profile_picture',
         false,
       );
@@ -356,13 +369,15 @@ class $SharedTodosTable extends SharedTodos
     implements TableInfo<SharedTodos, SharedTodo> {
   final GeneratedDatabase _db;
   $SharedTodosTable(this._db);
+  GeneratedIntColumn _todo;
   @override
-  GeneratedIntColumn get todo => GeneratedIntColumn(
+  GeneratedIntColumn get todo => _todo ??= GeneratedIntColumn(
         'todo',
         false,
       );
+  GeneratedIntColumn _user;
   @override
-  GeneratedIntColumn get user => GeneratedIntColumn(
+  GeneratedIntColumn get user => _user ??= GeneratedIntColumn(
         'user',
         false,
       );
@@ -398,10 +413,14 @@ class $SharedTodosTable extends SharedTodos
 
 abstract class _$TodoDb extends GeneratedDatabase {
   _$TodoDb(QueryExecutor e) : super(const SqlTypeSystem.withDefaults(), e);
-  $TodosTableTable get todosTable => $TodosTableTable(this);
+  $TodosTableTable _todosTable;
-  $CategoriesTable get categories => $CategoriesTable(this);
+  $TodosTableTable get todosTable => _todosTable ??= $TodosTableTable(this);
-  $UsersTable get users => $UsersTable(this);
+  $CategoriesTable _categories;
-  $SharedTodosTable get sharedTodos => $SharedTodosTable(this);
+  $CategoriesTable get categories => _categories ??= $CategoriesTable(this);
+  $UsersTable _users;
+  $UsersTable get users => _users ??= $UsersTable(this);
+  $SharedTodosTable _sharedTodos;
+  $SharedTodosTable get sharedTodos => _sharedTodos ??= $SharedTodosTable(this);
   @override
   List<TableInfo> get allTables => [todosTable, categories, users, sharedTodos];
 }

moor_generator/CHANGELOG.md

@@ -1,5 +1,6 @@
 ## 1.2.0
 - Blob data type
+- Generated classes now use lazy getters instead of recalculating fields on each access
 
 ## 1.1.0
 - The generated data classes now implement `toString()`

moor_generator/lib/src/writer/database_writer.dart

@@ -1,6 +1,7 @@
 import 'package:recase/recase.dart';
 import 'package:moor_generator/src/model/specified_database.dart';
 import 'package:moor_generator/src/writer/table_writer.dart';
+import 'utils.dart';
 
 class DatabaseWriter {
   final SpecifiedDatabase db;
@@ -25,26 +26,26 @@ class DatabaseWriter {
       tableGetters.add(tableFieldName);
       final tableClassName = table.tableInfoName;
 
-      buffer.write(
+      writeMemoizedGetter(
-          '$tableClassName get $tableFieldName => $tableClassName(this);');
+        buffer: buffer,
+        getterName: tableFieldName,
+        returnType: tableClassName,
+        code: '$tableClassName(this)',
+      );
     }
 
-    // Write fields to access an dao. We use a lazy getter:
+    // Write fields to access an dao. We use a lazy getter for that.
-    /*
-        DaoType _daoName;
-        DaoType get daoName => _daoName ??= DaoType(this);
-     */
     for (var dao in db.daos) {
       final typeName = dao.displayName;
       final getterName = ReCase(typeName).camelCase;
-      final fieldName = '_$getterName';
-
       final databaseImplName = db.fromClass.name;
 
-      buffer
+      writeMemoizedGetter(
-        ..write('$typeName $fieldName;\n')
+        buffer: buffer,
-        ..write('$typeName get $getterName => $fieldName ??= '
+        getterName: getterName,
-            '$typeName(this as $databaseImplName);');
+        returnType: typeName,
+        code: '$typeName(this as $databaseImplName)',
+      );
     }
 
     // Write List of tables, close bracket for class

moor_generator/lib/src/writer/table_writer.dart

@@ -1,6 +1,7 @@
 import 'package:moor_generator/src/model/specified_column.dart';
 import 'package:moor_generator/src/model/specified_table.dart';
 import 'package:moor_generator/src/writer/data_class_writer.dart';
+import 'package:moor_generator/src/writer/utils.dart';
 
 class TableWriter {
   final SpecifiedTable table;
@@ -97,25 +98,31 @@ class TableWriter {
       }
     }
 
-    // @override
+    // GeneratedIntColumn('sql_name', isNullable, additionalField: true)
-    // GeneratedIntColumn get id => GeneratedIntColumn('sql_name', isNullable);
+    final expressionBuffer = StringBuffer()
-    buffer
+      ..write(column.implColumnTypeName)
-      ..write('@override \n')
+      ..write('(\'${column.name.name}\', $isNullable, ');
-      ..write('${column.implColumnTypeName} get ${column.dartGetterName} => '
-          '${column.implColumnTypeName}(\'${column.name.name}\', $isNullable, ');
 
     var first = true;
     additionalParams.forEach((name, value) {
       if (!first) {
-        buffer.write(', ');
+        expressionBuffer.write(', ');
       } else {
         first = false;
       }
 
-      buffer..write(name)..write(': ')..write(value);
+      expressionBuffer..write(name)..write(': ')..write(value);
     });
 
-    buffer.write(');\n');
+    expressionBuffer.write(')');
+
+    writeMemoizedGetter(
+      buffer: buffer,
+      getterName: column.dartGetterName,
+      returnType: column.implColumnTypeName,
+      code: expressionBuffer.toString(),
+      hasOverride: true,
+    );
   }
 
   void _writeValidityCheckMethod(StringBuffer buffer) {

moor_generator/lib/src/writer/utils.dart

@@ -0,0 +1,21 @@
+import 'package:meta/meta.dart';
+
+/// Writes the following dart code into the [buffer]:
+/// ```
+/// ReturnType _getterName;
+/// ReturnType get getterName => _getterName ??= code;
+/// ```
+/// This means that [code] should be an expression without any trailing
+/// semicolon.
+void writeMemoizedGetter(
+    {@required StringBuffer buffer,
+    @required String getterName,
+    @required String returnType,
+    @required String code,
+    bool hasOverride}) {
+  buffer.write('$returnType _$getterName;\n');
+  if (hasOverride == true) {
+    buffer.write('@override\n');
+  }
+  buffer.write('$returnType get $getterName => _$getterName ??= $code;');
+}