fix constant hooks

Author: schultek

packages/dart_mappable_builder/CHANGELOG.md

@@ -3,6 +3,7 @@
 - Added support for `shallowEncoding` and `includeTypeId` options of `@MappableClass()`.
 - Fixed escaping of enum values.
 - Fixed copyWith method for unbounded and nullable-bounded generic types.
+- Fixed bug when using top-level variables as hooks.
 
 # 4.4.0
 

packages/dart_mappable_builder/lib/src/elements/class/class_mapper_element.dart

@@ -1,3 +1,4 @@
+import 'package:analyzer/dart/ast/ast.dart';
 import 'package:analyzer/dart/element/element.dart';
 import 'package:dart_mappable/dart_mappable.dart';
 
@@ -74,7 +75,11 @@ abstract class ClassMapperElement extends InterfaceMapperElement<ClassElement>
     if (hook != null && !hook.isNull) {
       var node = annotation.getPropertyNode('hook');
       if (node != null) {
-        return node.toSource();
+        var hook = node.toSource();
+        if (node is InstanceCreationExpression) {
+          hook = 'const $hook';
+        }
+        return hook;
       }
     }
     return null;

packages/dart_mappable_builder/lib/src/generators/mixins/decoding_mixin.dart

@@ -12,15 +12,18 @@ mixin DecodingMixin on MapperGenerator<TargetClassMapperElement> {
     if (hook != null) {
       output.write('''
         @override
-        final MappingHook hook = const $hook;
+        final MappingHook hook = $hook;
       ''');
     }
 
     var superHooks = _getSuperHooks(element);
     if (superHooks.isNotEmpty) {
+      final hook = superHooks.length == 1
+          ? superHooks.first
+          : 'ChainedHook([${superHooks.map((h) => h.startsWith('const ') ? h.substring(6) : h).join(', ')}])';
       output.write('''
         @override
-        final MappingHook superHook = const ${superHooks.length == 1 ? superHooks.first : 'ChainedHook([${superHooks.join(', ')}])'};
+        final MappingHook superHook = $hook;
         
       ''');
     }

packages/dart_mappable_builder/lib/src/mapper_group.dart

@@ -247,7 +247,10 @@ class MapperElementGroup {
             resolveBounds: resolveBounds,
             resolveBoundsDeep: resolveBoundsDeep);
       }
-      if (withNullability && t.isNullable && !type.endsWith('?')) {
+      if (withNullability &&
+          t.isNullable &&
+          !type.endsWith('?') &&
+          type != 'dynamic') {
         type += '?';
       }
       return type;