Migrate to update companions everywhere :)

moor/example/example.g.dart

@@ -76,18 +76,6 @@ class CategoriesCompanion extends UpdateCompanion<Category> {
     this.id = const Value.absent(),
     this.description = const Value.absent(),
   });
-  @override
-  bool isValuePresent(int index) {
-    switch (index) {
-      case 0:
-        return id.present;
-      case 1:
-        return description.present;
-      default:
-        throw ArgumentError(
-            'Hit an invalid state while serializing data. Did you run the build step?');
-    }
-  }
 }
 
 class $CategoriesTable extends Categories
@@ -126,14 +114,19 @@ class $CategoriesTable extends Categories
   @override
   final String actualTableName = 'categories';
   @override
-  VerificationContext validateIntegrity(CategoriesCompanion d) {
+  VerificationContext validateIntegrity(CategoriesCompanion d,
+      {bool isInserting = false}) {
     final context = VerificationContext();
-    if (d.isValuePresent(0)) {
+    if (d.id.present) {
       context.handle(_idMeta, id.isAcceptableValue(d.id.value, _idMeta));
+    } else if (id.isRequired && isInserting) {
+      context.missing(_idMeta);
     }
-    if (d.isValuePresent(1)) {
+    if (d.description.present) {
       context.handle(_descriptionMeta,
           description.isAcceptableValue(d.description.value, _descriptionMeta));
+    } else if (description.isRequired && isInserting) {
+      context.missing(_descriptionMeta);
     }
     return context;
   }
@@ -265,22 +258,6 @@ class RecipesCompanion extends UpdateCompanion<Recipe> {
     this.instructions = const Value.absent(),
     this.category = const Value.absent(),
   });
-  @override
-  bool isValuePresent(int index) {
-    switch (index) {
-      case 0:
-        return id.present;
-      case 1:
-        return title.present;
-      case 2:
-        return instructions.present;
-      case 3:
-        return category.present;
-      default:
-        throw ArgumentError(
-            'Hit an invalid state while serializing data. Did you run the build step?');
-    }
-  }
 }
 
 class $RecipesTable extends Recipes with TableInfo<$RecipesTable, Recipe> {
@@ -338,24 +315,33 @@ class $RecipesTable extends Recipes with TableInfo<$RecipesTable, Recipe> {
   @override
   final String actualTableName = 'recipes';
   @override
-  VerificationContext validateIntegrity(RecipesCompanion d) {
+  VerificationContext validateIntegrity(RecipesCompanion d,
+      {bool isInserting = false}) {
     final context = VerificationContext();
-    if (d.isValuePresent(0)) {
+    if (d.id.present) {
       context.handle(_idMeta, id.isAcceptableValue(d.id.value, _idMeta));
+    } else if (id.isRequired && isInserting) {
+      context.missing(_idMeta);
     }
-    if (d.isValuePresent(1)) {
+    if (d.title.present) {
       context.handle(
           _titleMeta, title.isAcceptableValue(d.title.value, _titleMeta));
+    } else if (title.isRequired && isInserting) {
+      context.missing(_titleMeta);
     }
-    if (d.isValuePresent(2)) {
+    if (d.instructions.present) {
       context.handle(
           _instructionsMeta,
           instructions.isAcceptableValue(
               d.instructions.value, _instructionsMeta));
+    } else if (instructions.isRequired && isInserting) {
+      context.missing(_instructionsMeta);
     }
-    if (d.isValuePresent(3)) {
+    if (d.category.present) {
       context.handle(_categoryMeta,
           category.isAcceptableValue(d.category.value, _categoryMeta));
+    } else if (category.isRequired && isInserting) {
+      context.missing(_categoryMeta);
     }
     return context;
   }
@@ -475,20 +461,6 @@ class IngredientsCompanion extends UpdateCompanion<Ingredient> {
     this.name = const Value.absent(),
     this.caloriesPer100g = const Value.absent(),
   });
-  @override
-  bool isValuePresent(int index) {
-    switch (index) {
-      case 0:
-        return id.present;
-      case 1:
-        return name.present;
-      case 2:
-        return caloriesPer100g.present;
-      default:
-        throw ArgumentError(
-            'Hit an invalid state while serializing data. Did you run the build step?');
-    }
-  }
 }
 
 class $IngredientsTable extends Ingredients
@@ -539,20 +511,27 @@ class $IngredientsTable extends Ingredients
   @override
   final String actualTableName = 'ingredients';
   @override
-  VerificationContext validateIntegrity(IngredientsCompanion d) {
+  VerificationContext validateIntegrity(IngredientsCompanion d,
+      {bool isInserting = false}) {
     final context = VerificationContext();
-    if (d.isValuePresent(0)) {
+    if (d.id.present) {
       context.handle(_idMeta, id.isAcceptableValue(d.id.value, _idMeta));
+    } else if (id.isRequired && isInserting) {
+      context.missing(_idMeta);
     }
-    if (d.isValuePresent(1)) {
+    if (d.name.present) {
       context.handle(
           _nameMeta, name.isAcceptableValue(d.name.value, _nameMeta));
+    } else if (name.isRequired && isInserting) {
+      context.missing(_nameMeta);
     }
-    if (d.isValuePresent(2)) {
+    if (d.caloriesPer100g.present) {
       context.handle(
           _caloriesPer100gMeta,
           caloriesPer100g.isAcceptableValue(
               d.caloriesPer100g.value, _caloriesPer100gMeta));
+    } else if (caloriesPer100g.isRequired && isInserting) {
+      context.missing(_caloriesPer100gMeta);
     }
     return context;
   }
@@ -678,20 +657,6 @@ class IngredientInRecipesCompanion extends UpdateCompanion<IngredientInRecipe> {
     this.ingredient = const Value.absent(),
     this.amountInGrams = const Value.absent(),
   });
-  @override
-  bool isValuePresent(int index) {
-    switch (index) {
-      case 0:
-        return recipe.present;
-      case 1:
-        return ingredient.present;
-      case 2:
-        return amountInGrams.present;
-      default:
-        throw ArgumentError(
-            'Hit an invalid state while serializing data. Did you run the build step?');
-    }
-  }
 }
 
 class $IngredientInRecipesTable extends IngredientInRecipes
@@ -746,21 +711,28 @@ class $IngredientInRecipesTable extends IngredientInRecipes
   @override
   final String actualTableName = 'recipe_ingredients';
   @override
-  VerificationContext validateIntegrity(IngredientInRecipesCompanion d) {
+  VerificationContext validateIntegrity(IngredientInRecipesCompanion d,
+      {bool isInserting = false}) {
     final context = VerificationContext();
-    if (d.isValuePresent(0)) {
+    if (d.recipe.present) {
       context.handle(
           _recipeMeta, recipe.isAcceptableValue(d.recipe.value, _recipeMeta));
+    } else if (recipe.isRequired && isInserting) {
+      context.missing(_recipeMeta);
     }
-    if (d.isValuePresent(1)) {
+    if (d.ingredient.present) {
       context.handle(_ingredientMeta,
           ingredient.isAcceptableValue(d.ingredient.value, _ingredientMeta));
+    } else if (ingredient.isRequired && isInserting) {
+      context.missing(_ingredientMeta);
     }
-    if (d.isValuePresent(2)) {
+    if (d.amountInGrams.present) {
       context.handle(
           _amountInGramsMeta,
           amountInGrams.isAcceptableValue(
               d.amountInGrams.value, _amountInGramsMeta));
+    } else if (amountInGrams.isRequired && isInserting) {
+      context.missing(_amountInGramsMeta);
     }
     return context;
   }

moor/lib/src/runtime/data_class.dart

@@ -40,20 +40,13 @@ abstract class DataClass {
 /// database using [InsertStatement.insert] or [UpdateStatement.write].
 ///
 /// See also:
+/// - the explanation in the changelog for 1.5
 /// - https://github.com/simolus3/moor/issues/25
-abstract class UpdateCompanion<D extends DataClass> implements Insertable {
+abstract class UpdateCompanion<D extends DataClass> implements Insertable<D> {
   const UpdateCompanion();
 
-  /// Used internally by moor.
-  ///
-  /// Returns true if the column at the position [index] has been explicitly
-  /// set to a value.
-  // todo this doesn't need to exist anymore, remove before release and adapt
-  // moor_generator
-  bool isValuePresent(int index);
-
   @override
-  T createCompanion<T extends UpdateCompanion>(bool nullToAbsent) {
+  T createCompanion<T extends UpdateCompanion<D>>(bool nullToAbsent) {
     return this as T;
   }
 }

moor/lib/src/runtime/statements/insert.dart

@@ -118,6 +118,8 @@ class InsertStatement<D extends DataClass> {
           'Cannot writee null row into ${table.$tableName}');
     }
 
-    table.validateIntegrity(d.createCompanion(true)).throwIfInvalid(d);
+    table
+        .validateIntegrity(d.createCompanion(true), isInserting: true)
+        .throwIfInvalid(d);
   }
 }

moor/lib/src/runtime/statements/update.dart

@@ -56,10 +56,10 @@ class UpdateStatement<T extends Table, D extends DataClass> extends Query<T, D>
   /// See also: [replace], which does not require [where] statements and
   /// supports setting fields back to null.
   Future<int> write(Insertable<D> entity) async {
-    // todo needs to use entity as update companion here
+    final companion = entity.createCompanion(true);
-    table.validateIntegrity(null).throwIfInvalid(entity);
+    table.validateIntegrity(companion).throwIfInvalid(entity);
 
-    _updatedFields = table.entityToSql(entity.createCompanion(true))
+    _updatedFields = table.entityToSql(companion)
       ..remove((_, value) => value == null);
 
     if (_updatedFields.isEmpty) {
@@ -90,7 +90,9 @@ class UpdateStatement<T extends Table, D extends DataClass> extends Query<T, D>
     // We don't turn nulls to absent values here (as opposed to a regular
     // update, where only non-null fields will be written).
     final companion = entity.createCompanion(false);
-    table.validateIntegrity(companion).throwIfInvalid(entity);
+    table
+        .validateIntegrity(companion, isInserting: true)
+        .throwIfInvalid(entity);
     assert(
         whereExpr == null,
         'When using replace on an update statement, you may not use where(...)'

moor/lib/src/runtime/structure/error_handling.dart

@@ -33,6 +33,11 @@ class VerificationContext {
     }
   }
 
+  void missing(VerificationMeta meta) {
+    _errors[meta] = const VerificationResult.failure(
+        "This value was required, but isn't present");
+  }
+
   void throwIfInvalid(dynamic dataObject) {
     if (dataValid) return;
 

moor/lib/src/runtime/structure/table_info.dart

@@ -36,7 +36,8 @@ mixin TableInfo<TableDsl extends Table, D extends DataClass> {
 
   /// Validates that the given entity can be inserted into this table, meaning
   /// that it respects all constraints (nullability, text length, etc.).
-  VerificationContext validateIntegrity(covariant UpdateCompanion<D> instance);
+  VerificationContext validateIntegrity(covariant UpdateCompanion<D> instance,
+      {bool isInserting = false});
 
   /// Maps the given update companion to a [Map] that can be inserted into sql.
   /// The keys should represent the column name in sql, the values the

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

@@ -129,24 +129,6 @@ class TodosTableCompanion extends UpdateCompanion<TodoEntry> {
     this.targetDate = const Value.absent(),
     this.category = const Value.absent(),
   });
-  @override
-  bool isValuePresent(int index) {
-    switch (index) {
-      case 0:
-        return id.present;
-      case 1:
-        return title.present;
-      case 2:
-        return content.present;
-      case 3:
-        return targetDate.present;
-      case 4:
-        return category.present;
-      default:
-        throw ArgumentError(
-            'Hit an invalid state while serializing data. Did you run the build step?');
-    }
-  }
 }
 
 class $TodosTableTable extends TodosTable
@@ -218,26 +200,37 @@ class $TodosTableTable extends TodosTable
   @override
   final String actualTableName = 'todos';
   @override
-  VerificationContext validateIntegrity(TodosTableCompanion d) {
+  VerificationContext validateIntegrity(TodosTableCompanion d,
+      {bool isInserting = false}) {
     final context = VerificationContext();
-    if (d.isValuePresent(0)) {
+    if (d.id.present) {
       context.handle(_idMeta, id.isAcceptableValue(d.id.value, _idMeta));
+    } else if (id.isRequired && isInserting) {
+      context.missing(_idMeta);
     }
-    if (d.isValuePresent(1)) {
+    if (d.title.present) {
       context.handle(
           _titleMeta, title.isAcceptableValue(d.title.value, _titleMeta));
+    } else if (title.isRequired && isInserting) {
+      context.missing(_titleMeta);
     }
-    if (d.isValuePresent(2)) {
+    if (d.content.present) {
       context.handle(_contentMeta,
           content.isAcceptableValue(d.content.value, _contentMeta));
+    } else if (content.isRequired && isInserting) {
+      context.missing(_contentMeta);
     }
-    if (d.isValuePresent(3)) {
+    if (d.targetDate.present) {
       context.handle(_targetDateMeta,
           targetDate.isAcceptableValue(d.targetDate.value, _targetDateMeta));
+    } else if (targetDate.isRequired && isInserting) {
+      context.missing(_targetDateMeta);
     }
-    if (d.isValuePresent(4)) {
+    if (d.category.present) {
       context.handle(_categoryMeta,
           category.isAcceptableValue(d.category.value, _categoryMeta));
+    } else if (category.isRequired && isInserting) {
+      context.missing(_categoryMeta);
     }
     return context;
   }
@@ -346,18 +339,6 @@ class CategoriesCompanion extends UpdateCompanion<Category> {
     this.id = const Value.absent(),
     this.description = const Value.absent(),
   });
-  @override
-  bool isValuePresent(int index) {
-    switch (index) {
-      case 0:
-        return id.present;
-      case 1:
-        return description.present;
-      default:
-        throw ArgumentError(
-            'Hit an invalid state while serializing data. Did you run the build step?');
-    }
-  }
 }
 
 class $CategoriesTable extends Categories
@@ -393,14 +374,19 @@ class $CategoriesTable extends Categories
   @override
   final String actualTableName = 'categories';
   @override
-  VerificationContext validateIntegrity(CategoriesCompanion d) {
+  VerificationContext validateIntegrity(CategoriesCompanion d,
+      {bool isInserting = false}) {
     final context = VerificationContext();
-    if (d.isValuePresent(0)) {
+    if (d.id.present) {
       context.handle(_idMeta, id.isAcceptableValue(d.id.value, _idMeta));
+    } else if (id.isRequired && isInserting) {
+      context.missing(_idMeta);
     }
-    if (d.isValuePresent(1)) {
+    if (d.description.present) {
       context.handle(_descriptionMeta,
           description.isAcceptableValue(d.description.value, _descriptionMeta));
+    } else if (description.isRequired && isInserting) {
+      context.missing(_descriptionMeta);
     }
     return context;
   }
@@ -558,24 +544,6 @@ class UsersCompanion extends UpdateCompanion<User> {
     this.profilePicture = const Value.absent(),
     this.creationTime = const Value.absent(),
   });
-  @override
-  bool isValuePresent(int index) {
-    switch (index) {
-      case 0:
-        return id.present;
-      case 1:
-        return name.present;
-      case 2:
-        return isAwesome.present;
-      case 3:
-        return profilePicture.present;
-      case 4:
-        return creationTime.present;
-      default:
-        throw ArgumentError(
-            'Hit an invalid state while serializing data. Did you run the build step?');
-    }
-  }
 }
 
 class $UsersTable extends Users with TableInfo<$UsersTable, User> {
@@ -643,30 +611,41 @@ class $UsersTable extends Users with TableInfo<$UsersTable, User> {
   @override
   final String actualTableName = 'users';
   @override
-  VerificationContext validateIntegrity(UsersCompanion d) {
+  VerificationContext validateIntegrity(UsersCompanion d,
+      {bool isInserting = false}) {
     final context = VerificationContext();
-    if (d.isValuePresent(0)) {
+    if (d.id.present) {
       context.handle(_idMeta, id.isAcceptableValue(d.id.value, _idMeta));
+    } else if (id.isRequired && isInserting) {
+      context.missing(_idMeta);
     }
-    if (d.isValuePresent(1)) {
+    if (d.name.present) {
       context.handle(
           _nameMeta, name.isAcceptableValue(d.name.value, _nameMeta));
+    } else if (name.isRequired && isInserting) {
+      context.missing(_nameMeta);
     }
-    if (d.isValuePresent(2)) {
+    if (d.isAwesome.present) {
       context.handle(_isAwesomeMeta,
           isAwesome.isAcceptableValue(d.isAwesome.value, _isAwesomeMeta));
+    } else if (isAwesome.isRequired && isInserting) {
+      context.missing(_isAwesomeMeta);
     }
-    if (d.isValuePresent(3)) {
+    if (d.profilePicture.present) {
       context.handle(
           _profilePictureMeta,
           profilePicture.isAcceptableValue(
               d.profilePicture.value, _profilePictureMeta));
+    } else if (profilePicture.isRequired && isInserting) {
+      context.missing(_profilePictureMeta);
     }
-    if (d.isValuePresent(4)) {
+    if (d.creationTime.present) {
       context.handle(
           _creationTimeMeta,
           creationTime.isAcceptableValue(
               d.creationTime.value, _creationTimeMeta));
+    } else if (creationTime.isRequired && isInserting) {
+      context.missing(_creationTimeMeta);
     }
     return context;
   }
@@ -775,18 +754,6 @@ class SharedTodosCompanion extends UpdateCompanion<SharedTodo> {
     this.todo = const Value.absent(),
     this.user = const Value.absent(),
   });
-  @override
-  bool isValuePresent(int index) {
-    switch (index) {
-      case 0:
-        return todo.present;
-      case 1:
-        return user.present;
-      default:
-        throw ArgumentError(
-            'Hit an invalid state while serializing data. Did you run the build step?');
-    }
-  }
 }
 
 class $SharedTodosTable extends SharedTodos
@@ -827,15 +794,20 @@ class $SharedTodosTable extends SharedTodos
   @override
   final String actualTableName = 'shared_todos';
   @override
-  VerificationContext validateIntegrity(SharedTodosCompanion d) {
+  VerificationContext validateIntegrity(SharedTodosCompanion d,
+      {bool isInserting = false}) {
     final context = VerificationContext();
-    if (d.isValuePresent(0)) {
+    if (d.todo.present) {
       context.handle(
           _todoMeta, todo.isAcceptableValue(d.todo.value, _todoMeta));
+    } else if (todo.isRequired && isInserting) {
+      context.missing(_todoMeta);
     }
-    if (d.isValuePresent(1)) {
+    if (d.user.present) {
       context.handle(
           _userMeta, user.isAcceptableValue(d.user.value, _userMeta));
+    } else if (user.isRequired && isInserting) {
+      context.missing(_userMeta);
     }
     return context;
   }
@@ -945,18 +917,6 @@ class TableWithoutPKCompanion extends UpdateCompanion<TableWithoutPKData> {
     this.notReallyAnId = const Value.absent(),
     this.someFloat = const Value.absent(),
   });
-  @override
-  bool isValuePresent(int index) {
-    switch (index) {
-      case 0:
-        return notReallyAnId.present;
-      case 1:
-        return someFloat.present;
-      default:
-        throw ArgumentError(
-            'Hit an invalid state while serializing data. Did you run the build step?');
-    }
-  }
 }
 
 class $TableWithoutPKTable extends TableWithoutPK
@@ -999,17 +959,22 @@ class $TableWithoutPKTable extends TableWithoutPK
   @override
   final String actualTableName = 'table_without_p_k';
   @override
-  VerificationContext validateIntegrity(TableWithoutPKCompanion d) {
+  VerificationContext validateIntegrity(TableWithoutPKCompanion d,
+      {bool isInserting = false}) {
     final context = VerificationContext();
-    if (d.isValuePresent(0)) {
+    if (d.notReallyAnId.present) {
       context.handle(
           _notReallyAnIdMeta,
           notReallyAnId.isAcceptableValue(
               d.notReallyAnId.value, _notReallyAnIdMeta));
+    } else if (notReallyAnId.isRequired && isInserting) {
+      context.missing(_notReallyAnIdMeta);
     }
-    if (d.isValuePresent(1)) {
+    if (d.someFloat.present) {
       context.handle(_someFloatMeta,
           someFloat.isAcceptableValue(d.someFloat.value, _someFloatMeta));
+    } else if (someFloat.isRequired && isInserting) {
+      context.missing(_someFloatMeta);
     }
     return context;
   }

moor/test/error_handling_test.dart

@@ -6,7 +6,10 @@ import 'data/utils/mocks.dart';
 
 // the content is set to non-null and the title must be between 4 and 16 chars
 // long
-final nullContent = TodoEntry(title: 'Test', content: null);
+final nullContent = const TodosTableCompanion(
+    title: Value.use('Test'), content: Value.use(null));
+final absentContent = const TodosTableCompanion(
+    title: Value.use('Test'), content: Value.absent());
 final shortTitle = TodoEntry(title: 'A', content: 'content');
 final longTitle = TodoEntry(title: 'A ${'very' * 5} long title', content: 'hi');
 final valid = TodoEntry(title: 'Test', content: 'Some content');
@@ -26,6 +29,11 @@ void main() {
       throwsA(predicate<InvalidDataException>(
           (e) => e.message.contains('not nullable'))),
     );
+    expect(
+      () => db.into(db.todosTable).insert(absentContent),
+      throwsA(predicate<InvalidDataException>(
+          (e) => e.message.contains('was required, but'))),
+    );
     expect(
       () => db.into(db.todosTable).insert(shortTitle),
       throwsA(predicate<InvalidDataException>(

moor_flutter/example/lib/database/database.g.dart

@@ -110,22 +110,6 @@ class TodosCompanion extends UpdateCompanion<TodoEntry> {
     this.targetDate = const Value.absent(),
     this.category = const Value.absent(),
   });
-  @override
-  bool isValuePresent(int index) {
-    switch (index) {
-      case 0:
-        return id.present;
-      case 1:
-        return content.present;
-      case 2:
-        return targetDate.present;
-      case 3:
-        return category.present;
-      default:
-        throw ArgumentError(
-            'Hit an invalid state while serializing data. Did you run the build step?');
-    }
-  }
 }
 
 class $TodosTable extends Todos with TableInfo<$TodosTable, TodoEntry> {
@@ -183,22 +167,31 @@ class $TodosTable extends Todos with TableInfo<$TodosTable, TodoEntry> {
   @override
   final String actualTableName = 'todos';
   @override
-  VerificationContext validateIntegrity(TodosCompanion d) {
+  VerificationContext validateIntegrity(TodosCompanion d,
+      {bool isInserting = false}) {
     final context = VerificationContext();
-    if (d.isValuePresent(0)) {
+    if (d.id.present) {
       context.handle(_idMeta, id.isAcceptableValue(d.id.value, _idMeta));
+    } else if (id.isRequired && isInserting) {
+      context.missing(_idMeta);
     }
-    if (d.isValuePresent(1)) {
+    if (d.content.present) {
       context.handle(_contentMeta,
           content.isAcceptableValue(d.content.value, _contentMeta));
+    } else if (content.isRequired && isInserting) {
+      context.missing(_contentMeta);
     }
-    if (d.isValuePresent(2)) {
+    if (d.targetDate.present) {
       context.handle(_targetDateMeta,
           targetDate.isAcceptableValue(d.targetDate.value, _targetDateMeta));
+    } else if (targetDate.isRequired && isInserting) {
+      context.missing(_targetDateMeta);
     }
-    if (d.isValuePresent(3)) {
+    if (d.category.present) {
       context.handle(_categoryMeta,
           category.isAcceptableValue(d.category.value, _categoryMeta));
+    } else if (category.isRequired && isInserting) {
+      context.missing(_categoryMeta);
     }
     return context;
   }
@@ -212,19 +205,19 @@ class $TodosTable extends Todos with TableInfo<$TodosTable, TodoEntry> {
   }
 
   @override
-  Map<String, Variable> entityToSql(TodoEntry d, {bool includeNulls = false}) {
+  Map<String, Variable> entityToSql(TodosCompanion d) {
     final map = <String, Variable>{};
-    if (d.id != null || includeNulls) {
+    if (d.id.present) {
-      map['id'] = Variable<int, IntType>(d.id);
+      map['id'] = Variable<int, IntType>(d.id.value);
     }
-    if (d.content != null || includeNulls) {
+    if (d.content.present) {
-      map['content'] = Variable<String, StringType>(d.content);
+      map['content'] = Variable<String, StringType>(d.content.value);
     }
-    if (d.targetDate != null || includeNulls) {
+    if (d.targetDate.present) {
-      map['target_date'] = Variable<DateTime, DateTimeType>(d.targetDate);
+      map['target_date'] = Variable<DateTime, DateTimeType>(d.targetDate.value);
     }
-    if (d.category != null || includeNulls) {
+    if (d.category.present) {
-      map['category'] = Variable<int, IntType>(d.category);
+      map['category'] = Variable<int, IntType>(d.category.value);
     }
     return map;
   }
@@ -304,18 +297,6 @@ class CategoriesCompanion extends UpdateCompanion<Category> {
     this.id = const Value.absent(),
     this.description = const Value.absent(),
   });
-  @override
-  bool isValuePresent(int index) {
-    switch (index) {
-      case 0:
-        return id.present;
-      case 1:
-        return description.present;
-      default:
-        throw ArgumentError(
-            'Hit an invalid state while serializing data. Did you run the build step?');
-    }
-  }
 }
 
 class $CategoriesTable extends Categories
@@ -354,14 +335,19 @@ class $CategoriesTable extends Categories
   @override
   final String actualTableName = 'categories';
   @override
-  VerificationContext validateIntegrity(CategoriesCompanion d) {
+  VerificationContext validateIntegrity(CategoriesCompanion d,
+      {bool isInserting = false}) {
     final context = VerificationContext();
-    if (d.isValuePresent(0)) {
+    if (d.id.present) {
       context.handle(_idMeta, id.isAcceptableValue(d.id.value, _idMeta));
+    } else if (id.isRequired && isInserting) {
+      context.missing(_idMeta);
     }
-    if (d.isValuePresent(1)) {
+    if (d.description.present) {
       context.handle(_descriptionMeta,
           description.isAcceptableValue(d.description.value, _descriptionMeta));
+    } else if (description.isRequired && isInserting) {
+      context.missing(_descriptionMeta);
     }
     return context;
   }
@@ -375,13 +361,13 @@ class $CategoriesTable extends Categories
   }
 
   @override
-  Map<String, Variable> entityToSql(Category d, {bool includeNulls = false}) {
+  Map<String, Variable> entityToSql(CategoriesCompanion d) {
     final map = <String, Variable>{};
-    if (d.id != null || includeNulls) {
+    if (d.id.present) {
-      map['id'] = Variable<int, IntType>(d.id);
+      map['id'] = Variable<int, IntType>(d.id.value);
     }
-    if (d.description != null || includeNulls) {
+    if (d.description.present) {
-      map['desc'] = Variable<String, StringType>(d.description);
+      map['desc'] = Variable<String, StringType>(d.description.value);
     }
     return map;
   }

moor_generator/lib/src/writer/table_writer.dart

@@ -163,23 +163,22 @@ class TableWriter {
   void _writeValidityCheckMethod(StringBuffer buffer) {
     buffer
       ..write('@override\nVerificationContext validateIntegrity'
-          '(${table.updateCompanionName} d) {\n')
+          '(${table.updateCompanionName} d, {bool isInserting = false}) {\n')
       ..write('final context = VerificationContext();\n');
 
-    for (var i = 0; i < table.columns.length; i++) {
+    for (var column in table.columns) {
-      final column = table.columns[i];
       final getterName = column.dartGetterName;
       final metaName = _fieldNameForColumnMeta(column);
 
       buffer
-        ..write('if (d.isValuePresent($i)) {\n')
+        ..write('if (d.$getterName.present) {\n')
         ..write('context.handle('
             '$metaName, '
             '$getterName.isAcceptableValue(d.$getterName.value, $metaName));')
+        ..write('} else if ($getterName.isRequired && isInserting) {\n')
+        ..write('context.missing($metaName);\n')
         ..write('}\n');
     }
-
-    // todo verify that all required columns are present
     buffer.write('return context;\n}\n');
   }
 

moor_generator/lib/src/writer/update_companion_writer.dart

@@ -12,7 +12,6 @@ class UpdateCompanionWriter {
         'extends UpdateCompanion<${table.dartTypeName}> {\n');
     _writeFields(buffer);
     _writeConstructor(buffer);
-    _writeIsPresentOverride(buffer);
 
     buffer.write('}\n');
   }
@@ -33,21 +32,4 @@ class UpdateCompanionWriter {
 
     buffer.write('});\n');
   }
-
-  void _writeIsPresentOverride(StringBuffer buffer) {
-    buffer
-      ..write('@override\nbool isValuePresent(int index) {\n')
-      ..write('switch (index) {');
-
-    for (var i = 0; i < table.columns.length; i++) {
-      final getterName = table.columns[i].dartGetterName;
-      buffer.write('case $i: return $getterName.present;\n');
-    }
-
-    buffer
-      ..write('default: throw ArgumentError('
-          "'Hit an invalid state while serializing data. Did you run the build "
-          "step?');")
-      ..write('}\n}\n');
-  }
 }