(refactor) Pull out query method return type into own class

floor_generator/lib/misc/change_method_processor_helper.dart

@@ -2,6 +2,7 @@
 import 'package:analyzer/dart/element/element.dart';
 import 'package:analyzer/dart/element/type.dart';
 import 'package:floor_generator/misc/type_utils.dart';
+import 'package:floor_generator/processor/error/change_method_processor_error.dart';
 import 'package:floor_generator/value_object/entity.dart';
 import 'package:source_gen/source_gen.dart';
 
@@ -10,11 +11,14 @@ class ChangeMethodProcessorHelper {
   final MethodElement _methodElement;
   final List<Entity> _entities;
 
-  const ChangeMethodProcessorHelper(
+  final ChangeMethodProcessorError processorError;
+
+  ChangeMethodProcessorHelper(
     final MethodElement methodElement,
     final List<Entity> entities,
   )   : _methodElement = methodElement,
-        _entities = entities;
+        _entities = entities,
+        processorError = ChangeMethodProcessorError(methodElement);
 
   ParameterElement getParameterElement() {
     final parameters = _methodElement.parameters;
@@ -32,7 +36,7 @@ class ChangeMethodProcessorHelper {
     return parameters.first;
   }
 
-  DartType getFlattenedParameterType(
+  DartType _getFlattenedParameterType(
     final ParameterElement parameterElement,
   ) {
     final changesMultipleItems = parameterElement.type.isDartCoreList;
@@ -42,13 +46,30 @@ class ChangeMethodProcessorHelper {
         : parameterElement.type;
   }
 
-  Entity getEntity(final DartType flattenedParameterType) {
+  Entity getEntity(final ParameterElement parameterElement) {
+    final flattenedParameterType = _getFlattenedParameterType(parameterElement);
     return _entities.firstWhere(
         (entity) =>
-            entity.classElement.displayName ==
+            entity.className ==
             flattenedParameterType.getDisplayString(withNullability: false),
         orElse: () => throw InvalidGenerationSourceError(
             'You are trying to change an object which is not an entity.',
             element: _methodElement));
   }
+
+  DartType getFlattenedReturnType() {
+    return _methodElement.library.typeSystem.flatten(_methodElement.returnType);
+  }
+
+  void assertMethodReturnsFuture(String methodType) {
+    if (!_methodElement.returnType.isDartAsyncFuture) {
+      throw processorError.changeMustReturnIntOrVoidFuture(methodType);
+    }
+  }
+
+  void assertMethodReturnsIntOrVoid(String methodType, final DartType flat) {
+    if (!flat.isVoid && !flat.isDartCoreInt) {
+      throw processorError.changeMustReturnIntOrVoidFuture(methodType);
+    }
+  }
 }

floor_generator/lib/processor/dao_processor.dart

@@ -59,8 +59,8 @@ class DaoProcessor extends Processor<Dao> {
     final transactionMethods = _getTransactionMethods(methods);
 
     final streamQueryables = queryMethods
-        .where((method) => method.returnsStream)
-        .map((method) => method.queryable);
+        .where((method) => method.returnType.isStream)
+        .map((method) => method.returnType.queryable);
     final streamEntities = streamQueryables.whereType<Entity>().toSet();
     final streamViews = streamQueryables.whereType<View>().toSet();
 

floor_generator/lib/processor/deletion_method_processor.dart

@@ -1,79 +1,38 @@
 // ignore_for_file: import_of_legacy_library_into_null_safe
 import 'package:analyzer/dart/element/element.dart';
-import 'package:analyzer/dart/element/type.dart';
 import 'package:floor_generator/misc/change_method_processor_helper.dart';
 import 'package:floor_generator/processor/processor.dart';
 import 'package:floor_generator/value_object/deletion_method.dart';
 import 'package:floor_generator/value_object/entity.dart';
-import 'package:source_gen/source_gen.dart';
 
 class DeletionMethodProcessor implements Processor<DeletionMethod> {
   final MethodElement _methodElement;
   final ChangeMethodProcessorHelper _helper;
 
   DeletionMethodProcessor(
-    final MethodElement methodElement,
+    this._methodElement,
     final List<Entity> entities, [
     final ChangeMethodProcessorHelper? changeMethodProcessorHelper,
-  ])  : _methodElement = methodElement,
-        _helper = changeMethodProcessorHelper ??
-            ChangeMethodProcessorHelper(methodElement, entities);
+  ])  : _helper = changeMethodProcessorHelper ??
+            ChangeMethodProcessorHelper(_methodElement, entities);
 
   @override
   DeletionMethod process() {
-    final name = _methodElement.name;
-    final returnType = _methodElement.returnType;
+    _helper.assertMethodReturnsFuture('Deletion');
 
-    _assertMethodReturnsFuture(returnType);
+    final flattenedReturnType = _helper.getFlattenedReturnType();
 
-    final flattenedReturnType = _getFlattenedReturnType(returnType);
-    _assertMethodReturnsNoList(flattenedReturnType);
-
-    final returnsVoid = flattenedReturnType.isVoid;
-    final returnsInt = flattenedReturnType.isDartCoreInt;
-
-    if (!returnsVoid && !returnsInt) {
-      throw InvalidGenerationSourceError(
-        'Deletion methods have to return a Future of either void or int.',
-        element: _methodElement,
-      );
-    }
+    _helper.assertMethodReturnsIntOrVoid('Deletion', flattenedReturnType);
 
     final parameterElement = _helper.getParameterElement();
-    final flattenedParameterType =
-        _helper.getFlattenedParameterType(parameterElement);
-
-    final entity = _helper.getEntity(flattenedParameterType);
+    final entity = _helper.getEntity(parameterElement);
 
     return DeletionMethod(
-      _methodElement,
-      name,
-      returnType,
-      flattenedReturnType,
+      _methodElement.name,
+      _methodElement.returnType,
+      flattenedReturnType.isVoid,
       parameterElement,
       entity,
     );
   }
-
-  DartType _getFlattenedReturnType(final DartType returnType) {
-    return _methodElement.library.typeSystem.flatten(returnType);
-  }
-
-  void _assertMethodReturnsNoList(final DartType flattenedReturnType) {
-    if (flattenedReturnType.isDartCoreList) {
-      throw InvalidGenerationSourceError(
-        'Deletion methods have to return a Future of either void or int but not a list.',
-        element: _methodElement,
-      );
-    }
-  }
-
-  void _assertMethodReturnsFuture(final DartType returnType) {
-    if (!returnType.isDartAsyncFuture) {
-      throw InvalidGenerationSourceError(
-        'Deletion methods have to return a Future.',
-        element: _methodElement,
-      );
-    }
-  }
 }

floor_generator/lib/processor/entity_processor.dart

@@ -39,7 +39,7 @@ class EntityProcessor extends QueryableProcessor<Entity> {
     }
 
     return Entity(
-      classElement,
+      classElement.displayName,
       name,
       fields,
       _getPrimaryKey(fields),

floor_generator/lib/processor/error/change_method_processor_error.dart

@@ -0,0 +1,28 @@
+import 'package:analyzer/dart/element/element.dart';
+import 'package:floor_generator/processor/error/processor_error.dart';
+
+class ChangeMethodProcessorError {
+  final MethodElement _methodElement;
+
+  const ChangeMethodProcessorError(final MethodElement methodElement)
+      : _methodElement = methodElement;
+
+  ProcessorError changeMustReturnIntOrVoidFuture(String type) {
+    return ProcessorError(
+      message: '$type methods have to return a Future of either void or int.',
+      todo:
+          'Give the method a return type of either `Future<void>` or `Future<int>`.',
+      element: _methodElement,
+    );
+  }
+
+  ProcessorError get insertMustReturnIntOrVoidFutureList {
+    return ProcessorError(
+      message:
+          'Insertion methods have to return a Future of either void or int or List<int>.',
+      todo:
+          'Give the method a return type of either `Future<void>`, `Future<int>` or `Future<List<int>>`.',
+      element: _methodElement,
+    );
+  }
+}

floor_generator/lib/processor/error/query_method_processor_error.dart

@@ -25,6 +25,15 @@ class QueryMethodProcessorError {
     );
   }
 
+  InvalidGenerationSourceError get doesNotReturnFutureVoid {
+    return InvalidGenerationSourceError(
+      'A query returning `void` has to return exactly `Future<void>`.',
+      todo:
+          'Define the return type as `Future<void>` or return a non-empty value.',
+      element: _methodElement,
+    );
+  }
+
   ProcessorError get doesNotReturnNullableStream {
     return ProcessorError(
       message: 'Queries returning streams of single elements might emit null.',

floor_generator/lib/processor/insertion_method_processor.dart

@@ -17,66 +17,32 @@ class InsertionMethodProcessor implements Processor<InsertionMethod> {
   final ChangeMethodProcessorHelper _helper;
 
   InsertionMethodProcessor(
-    final MethodElement methodElement,
+    this._methodElement,
     final List<Entity> entities, [
     final ChangeMethodProcessorHelper? changeMethodProcessorHelper,
-  ])  : _methodElement = methodElement,
-        _helper = changeMethodProcessorHelper ??
-            ChangeMethodProcessorHelper(methodElement, entities);
+  ])  : _helper = changeMethodProcessorHelper ??
+            ChangeMethodProcessorHelper(_methodElement, entities);
 
   @override
   InsertionMethod process() {
-    final name = _methodElement.name;
-    final returnType = _methodElement.returnType;
+    _assertMethodReturnsFuture();
 
-    _assertMethodReturnsFuture(returnType);
-
-    final returnsList = _getReturnsList(returnType);
-    final flattenedReturnType =
-        _getFlattenedReturnType(returnType, returnsList);
-
-    final returnsVoid = flattenedReturnType.isVoid;
-    final returnsInt = flattenedReturnType.isDartCoreInt;
-    final returnsIntList = returnsList && flattenedReturnType.isDartCoreInt;
-
-    if (!returnsVoid && !returnsIntList && !returnsInt) {
-      throw InvalidGenerationSourceError(
-        'Insertion methods have to return a Future of either void, int or List<int>.',
-        element: _methodElement,
-      );
-    }
+    final flattenedReturnType = _getAndCheckFlatReturnType();
 
     final parameterElement = _helper.getParameterElement();
-    final flattenedParameterType =
-        _helper.getFlattenedParameterType(parameterElement);
-
-    final entity = _helper.getEntity(flattenedParameterType);
+    final entity = _helper.getEntity(parameterElement);
     final onConflict = _getOnConflictStrategy();
 
     return InsertionMethod(
-      _methodElement,
-      name,
-      returnType,
-      flattenedReturnType,
+      _methodElement.name,
+      _methodElement.returnType,
+      flattenedReturnType.isVoid,
       parameterElement,
       entity,
       onConflict,
     );
   }
 
-  bool _getReturnsList(final DartType returnType) {
-    final type = _methodElement.library.typeSystem.flatten(returnType);
-    return type.isDartCoreList;
-  }
-
-  DartType _getFlattenedReturnType(
-    final DartType returnType,
-    final bool returnsList,
-  ) {
-    final type = _methodElement.library.typeSystem.flatten(returnType);
-    return returnsList ? type.flatten() : type;
-  }
-
   String _getOnConflictStrategy() {
     final onConflictStrategy = _methodElement
         .getAnnotation(annotations.Insert)
@@ -93,12 +59,23 @@ class InsertionMethodProcessor implements Processor<InsertionMethod> {
     }
   }
 
-  void _assertMethodReturnsFuture(final DartType returnType) {
-    if (!returnType.isDartAsyncFuture) {
-      throw InvalidGenerationSourceError(
-        'Insertion methods have to return a Future.',
-        element: _methodElement,
-      );
+  void _assertMethodReturnsFuture() {
+    if (!_methodElement.returnType.isDartAsyncFuture) {
+      throw _helper.processorError.insertMustReturnIntOrVoidFutureList;
+    }
+  }
+
+  DartType _getAndCheckFlatReturnType() {
+    DartType flattened = _helper.getFlattenedReturnType();
+    if (flattened.isVoid || flattened.isDartCoreInt) {
+      return flattened;
+    }
+    if (flattened.isDartCoreList) {
+      flattened = flattened.flatten();
+      if (flattened.isDartCoreInt) {
+        return flattened;
+      }
     }
+    throw _helper.processorError.insertMustReturnIntOrVoidFutureList;
   }
 }