Merge pull request #20 from IO-Design-Team/feature/constructor-defaul…

…t-values

Support constructor parameter default values

hive/CHANGELOG.md

@@ -1,3 +1,7 @@
+## 2.5.0+1
+
+- Documentation updates for `HiveField` in support of `hive_ce_generator` changes
+
 ## 2.5.0
 
 - Adds `Target` annotations to `HiveField` and `HiveType` to prevent invalid usage

hive/lib/src/annotations/hive_field.dart

@@ -13,6 +13,8 @@ class HiveField {
 
   /// The default value of this field for class hive types.
   ///
+  /// This value takes precedence over constructor parameter default values.
+  ///
   /// In enum hive types set `true` to use this enum value as default value
   /// instead of null in null-safety.
   ///

hive/pubspec.yaml

@@ -1,6 +1,6 @@
 name: hive_ce
 description: Hive Community Edition - A spiritual continuation of Hive v2
-version: 2.5.0
+version: 2.5.0+1
 homepage: https://github.com/IO-Design-Team/hive_ce/tree/main/hive
 documentation: https://docs.hivedb.dev/
 

hive_generator/CHANGELOG.md

@@ -1,3 +1,10 @@
+## 1.5.0
+
+- Supports constructor parameter default values
+- No longer generates the `HiveRegistrar` if there are no adapters
+- Removes unnecessary print statement in `HiveRegistrar` generator
+- Bumps `analyzer` to `^6.5.0` to deal with deprecations
+
 ## 1.4.0
 
 - Adds a generator to create a `HiveRegistrar` extension that allows registration of all generated `TypeAdapters` in one call

hive_generator/example/lib/hive_registrar.g.dart

@@ -7,6 +7,8 @@ extension HiveRegistrar on HiveInterface {
     registerAdapter(Class2Adapter());
     registerAdapter(EmptyClassAdapter());
     registerAdapter(IterableClassAdapter());
+    registerAdapter(ConstructorDefaultsAdapter());
+    registerAdapter(NullableTypesAdapter());
     registerAdapter(Enum1Adapter());
   }
 }

hive_generator/example/lib/types.dart

@@ -78,3 +78,39 @@ class IterableClass {
   @HiveField(3)
   final Set<List<String>> nestedSet;
 }
+
+@HiveType(typeId: 6)
+class ConstructorDefaults {
+  ConstructorDefaults({
+    this.a = 42,
+    this.b = '42',
+    this.c = true,
+    DateTime? d,
+  }) : d = d ?? DateTime.now();
+
+  @HiveField(0)
+  final int a;
+
+  @HiveField(1, defaultValue: '6 * 7')
+  final String b;
+
+  @HiveField(2)
+  final bool c;
+
+  @HiveField(3)
+  final DateTime d;
+}
+
+@HiveType(typeId: 7)
+class NullableTypes {
+  NullableTypes({this.a, this.b, this.c});
+
+  @HiveField(0)
+  final int? a;
+
+  @HiveField(1)
+  final String? b;
+
+  @HiveField(2)
+  final bool? c;
+}

hive_generator/lib/src/builder.dart

@@ -2,22 +2,33 @@ import 'package:analyzer/dart/constant/value.dart';
 import 'package:analyzer/dart/element/element.dart';
 import 'package:analyzer/dart/element/type.dart';
 
-/// TODO: Document this!
+/// Metadata about a field in a class adapter
 class AdapterField {
-  /// TODO: Document this!
+  /// The index of the field
+  ///
+  /// Determines the order fields are read and written
   final int index;
 
-  /// TODO: Document this!
+  /// The name of the field
   final String name;
 
-  /// TODO: Document this!
+  /// The type of the field
   final DartType type;
 
-  /// TODO: Document this!
-  final DartObject? defaultValue;
+  /// A default value provided by the field annotation
+  final DartObject? annotationDefault;
 
-  /// TODO: Document this!
-  AdapterField(this.index, this.name, this.type, this.defaultValue);
+  /// A default value provided by the constructor
+  final String? constructorDefault;
+
+  /// Constructor
+  AdapterField(
+    this.index,
+    this.name,
+    this.type,
+    this.annotationDefault,
+    this.constructorDefault,
+  );
 }
 
 /// TODO: Document this!

hive_generator/lib/src/class_builder.dart

@@ -1,6 +1,5 @@
 import 'dart:typed_data';
 
-import 'package:analyzer/dart/constant/value.dart';
 import 'package:analyzer/dart/element/nullability_suffix.dart';
 import 'package:analyzer/dart/element/type.dart';
 import 'package:hive_ce/hive.dart';
@@ -68,13 +67,7 @@ class ClassBuilder extends Builder {
         if (param.isNamed) {
           code.write('${param.name}: ');
         }
-        code.write(
-          _value(
-            param.type,
-            'fields[${field.index}]',
-            field.defaultValue,
-          ),
-        );
+        code.write(_value(param.type, field));
         code.writeln(',');
         fields.remove(field);
       }
@@ -86,24 +79,33 @@ class ClassBuilder extends Builder {
     // as initializing formals. We do so using cascades.
     for (final field in fields) {
       code.write('..${field.name} = ');
-      code.writeln(
-        _value(
-          field.type,
-          'fields[${field.index}]',
-          field.defaultValue,
-        ),
-      );
+      code.writeln(_value(field.type, field));
     }
 
     code.writeln(';');
 
     return code.toString();
   }
 
-  String _value(DartType type, String variable, DartObject? defaultValue) {
+  String _value(DartType type, AdapterField field) {
+    final variable = 'fields[${field.index}]';
     final value = _cast(type, variable);
-    if (defaultValue?.isNull != false) return value;
-    return '$variable == null ? ${constantToString(defaultValue!)} : $value';
+
+    final annotationDefaultIsNull = field.annotationDefault?.isNull ?? true;
+    final constructorDefaultIsNull = field.constructorDefault == null;
+
+    final String? defaultValue;
+    if (!annotationDefaultIsNull) {
+      defaultValue = constantToString(field.annotationDefault);
+    } else if (!constructorDefaultIsNull) {
+      defaultValue = field.constructorDefault;
+    } else {
+      defaultValue = null;
+    }
+
+    if (defaultValue == null) return value;
+
+    return '$variable == null ? $defaultValue : $value';
   }
 
   String _cast(DartType type, String variable) {
@@ -121,7 +123,7 @@ class ClassBuilder extends Builder {
     } else if (type.isDartCoreDouble) {
       return '($variable as num$suffix)$suffix.toDouble()';
     } else {
-      return '$variable as ${_displayString(type)}';
+      return '$variable as ${type.getDisplayString()}';
     }
   }
 
@@ -152,7 +154,7 @@ class ClassBuilder extends Builder {
 
       return '$suffix.map((e) => ${_cast(arg, 'e')})$cast';
     } else {
-      return '$suffix.cast<${_displayString(arg)}>()';
+      return '$suffix.cast<${arg.getDisplayString()}>()';
     }
   }
 
@@ -165,8 +167,8 @@ class ClassBuilder extends Builder {
       return '$suffix.map((dynamic k, dynamic v)=>'
           'MapEntry(${_cast(arg1, 'k')},${_cast(arg2, 'v')}))';
     } else {
-      return '$suffix.cast<${_displayString(arg1)}, '
-          '${_displayString(arg2)}>()';
+      return '$suffix.cast<${arg1.getDisplayString()}, '
+          '${arg2.getDisplayString()}>()';
     }
   }
 
@@ -212,16 +214,8 @@ String _accessorSuffixFromType(DartType type) {
 /// Suffix to use when casting a value to [type].
 /// $variable as $type$suffix
 String _suffixFromType(DartType type) {
-  if (type.nullabilitySuffix == NullabilitySuffix.star) {
-    return '';
-  }
-  if (type.nullabilitySuffix == NullabilitySuffix.question) {
-    return '?';
-  }
-  return '';
-}
-
-String _displayString(DartType e) {
-  final suffix = _suffixFromType(e);
-  return '${e.getDisplayString()}$suffix';
+  return switch (type.nullabilitySuffix) {
+    NullabilitySuffix.question => '?',
+    _ => '',
+  };
 }

hive_generator/lib/src/enum_builder.dart

@@ -20,7 +20,7 @@ class EnumBuilder extends Builder {
     }
 
     final defaultField = getters.firstWhere(
-      (it) => it.defaultValue?.toBoolValue() == true,
+      (it) => it.annotationDefault?.toBoolValue() == true,
       orElse: () => getters.first,
     );
     code.writeln('''

hive_generator/lib/src/registrar_generator.dart

@@ -14,8 +14,6 @@ class RegistrarBuilder implements Builder {
 
   @override
   Future<void> build(BuildStep buildStep) async {
-    final buffer = StringBuffer("import 'package:hive_ce/hive.dart';\n");
-
     final uris = <String>[];
     final adapters = <String>[];
     await for (final input
@@ -26,6 +24,11 @@ class RegistrarBuilder implements Builder {
       adapters.addAll((data['adapters'] as List).cast<String>());
     }
 
+    // Do not create the registrar if there are no adapters
+    if (adapters.isEmpty) return;
+
+    final buffer = StringBuffer("import 'package:hive_ce/hive.dart';\n");
+
     for (final uri in uris) {
       buffer.writeln("import '$uri';");
     }