Annotated COObject with nullability and lightweight generics

Core/COObject+Private.h

@@ -11,6 +11,8 @@
 
 @class CORelationshipCache, COObjectGraphContext;
 
+NS_ASSUME_NONNULL_BEGIN
+
 void SetterToProperty(const char *setter, size_t setterlen, char *prop);
 BOOL IsSetter(const char *selname, size_t sellen);
 
@@ -24,7 +26,7 @@ ETEntityDescription *entityDescriptionForObjectInRepository();
 /**
  * This method is only exposed to be used internally by CoreObject.
  */
-- (Class)coreObjectCollectionClassForPropertyDescription: (ETPropertyDescription *)propDesc;
+- (nullable Class)coreObjectCollectionClassForPropertyDescription: (ETPropertyDescription *)propDesc;
 /**
  * This method is only exposed to be used internally by CoreObject.
  *
@@ -57,7 +59,7 @@ ETEntityDescription *entityDescriptionForObjectInRepository();
 /**
  * This method is only exposed to be used internally by CoreObject.
  */
-@property (nonatomic, readonly) NSDictionary *additionalStoreItemUUIDs;
+@property (nonatomic, readonly) NSDictionary<NSString *, ETUUID *> *additionalStoreItemUUIDs;
 /**
  * This method is only exposed to be used internally by CoreObject.
  */
@@ -72,23 +74,23 @@ ETEntityDescription *entityDescriptionForObjectInRepository();
 /**
  * This method is only exposed to be used internally by CoreObject.
  */
-- (id)valueForStorageKey: (NSString *)key;
+- (nullable id)valueForStorageKey: (NSString *)key;
 /**
  * This method is only exposed to be used internally by CoreObject.
  */
-- (id)valueForStorageKey: (NSString *)key shouldLoad: (BOOL)shouldLoad;
+- (nullable id)valueForStorageKey: (NSString *)key shouldLoad: (BOOL)shouldLoad;
 /**
  * This method is only exposed to be used internally by CoreObject.
  */
-- (id)serializableValueForStorageKey: (NSString *)key;
+- (nullable id)serializableValueForStorageKey: (NSString *)key;
 /**
  * This method is only exposed to be used internally by CoreObject.
  */
-- (void)setValue: (id)value forStorageKey: (NSString *)key;
+- (void)setValue: (nullable id)value forStorageKey: (NSString *)key;
 /**
  * This method is only exposed to be used internally by CoreObject.
  */
-- (id)valueForProperty: (NSString *)key shouldLoad: (BOOL)shouldLoad;
+- (nullable id)valueForProperty: (NSString *)key shouldLoad: (BOOL)shouldLoad;
 /**
  * This method is only exposed to be used internally by CoreObject.
  *
@@ -135,11 +137,13 @@ ETEntityDescription *entityDescriptionForObjectInRepository();
 /**
  * This method is only exposed to be used in the CoreObject tests.
  */
-@property (nonatomic, readonly) NSSet *referringObjects;
+@property (nonatomic, readonly) NSSet<__kindof COObject *> *referringObjects;
 /**
  * This method is only exposed to be used internally by CoreObject.
  */
-- (void)replaceReferencesToObjectIdenticalTo: (COObject *)anObject
-                                  withObject: (COObject *)aReplacement;
+- (void)replaceReferencesToObjectIdenticalTo: (nullable COObject *)anObject
+                                  withObject: (nullable COObject *)aReplacement;
 
 @end
+
+NS_ASSUME_NONNULL_END

Core/COObject+RelationshipCache.h

@@ -8,19 +8,23 @@
 #import <Foundation/Foundation.h>
 #import <CoreObject/COObject.h>
 
+NS_ASSUME_NONNULL_BEGIN
+
 @interface COObject (RelationshipCache)
 
-- (void)updateCachedOutgoingRelationshipsForOldValue: (id)oldVal
-                                            newValue: (id)newVal
+- (void)updateCachedOutgoingRelationshipsForOldValue: (nullable id)oldVal
+                                            newValue: (nullable id)newVal
                            ofPropertyWithDescription: (ETPropertyDescription *)aProperty;
 - (void)removeCachedOutgoingRelationships;
 - (void)removeCachedOutgoingRelationshipsForCollectionValue: (id)obj
                                   ofPropertyWithDescription: (ETPropertyDescription *)aProperty;
 - (void)addCachedOutgoingRelationshipsForCollectionValue: (id)obj
                                ofPropertyWithDescription: (ETPropertyDescription *)aProperty;
-- (void)removeCachedOutgoingRelationshipsForValue: (id)aValue
+- (void)removeCachedOutgoingRelationshipsForValue: (nullable id)aValue
                         ofPropertyWithDescription: (ETPropertyDescription *)aProperty;
-- (void)addCachedOutgoingRelationshipsForValue: (id)aValue
+- (void)addCachedOutgoingRelationshipsForValue: (nullable id)aValue
                      ofPropertyWithDescription: (ETPropertyDescription *)aProperty;
 
 @end
+
+NS_ASSUME_NONNULL_END

Core/COObject.h

@@ -8,7 +8,10 @@
 #import <Foundation/Foundation.h>
 #import <EtoileFoundation/EtoileFoundation.h>
 
-@class COPersistentRoot, COEditingContext, CORevision, COBranch, CORelationshipCache, COObjectGraphContext, COCrossPersistentRootReferenceCache;
+@class COPersistentRoot, COEditingContext, CORevision, COBranch, COObjectGraphContext;
+@class CORelationshipCache, COCrossPersistentRootReferenceCache, COTag;
+
+NS_ASSUME_NONNULL_BEGIN
 
 /**
  * @group Core
@@ -500,17 +503,17 @@
  * Returns the branch when the receiver is persistent, otherwise
  * returns nil.
  */
-@property (nonatomic, readonly, weak) COBranch *branch;
+@property (nonatomic, readonly, weak, nullable) COBranch *branch;
 /**
  * Returns the persistent root when the receiver is persistent, otherwise 
  * returns nil.
  */
-@property (nonatomic, readonly, weak) COPersistentRoot *persistentRoot;
+@property (nonatomic, readonly, weak, nullable) COPersistentRoot *persistentRoot;
 /**
  * Returns the editing context when the receiver is persistent, otherwise
  * returns nil.
  */
-@property (nonatomic, readonly, weak) COEditingContext *editingContext;
+@property (nonatomic, readonly, weak, nullable) COEditingContext *editingContext;
 /**
  * Returns the object graph context owning the receiver.
  */
@@ -523,7 +526,7 @@
  *
  * See also -isRoot.
  */
-@property (nonatomic, readonly) id rootObject;
+@property (nonatomic, readonly, nullable) __kindof COObject *rootObject;
 /**
  * Returns whether the receiver is owned by a persistent root.
  *
@@ -551,6 +554,7 @@
  */
 @property (nonatomic, readonly) BOOL isShared;
 
+
 /** @taskunit History Attributes */
 
 
@@ -560,7 +564,7 @@
  *
  * See also -[COBranch currentRevision].
  */
-@property (nonatomic, readonly) CORevision *revision;
+@property (nonatomic, readonly, nullable) CORevision *revision;
 
 
 /** @taskunit Basic Properties */
@@ -569,7 +573,7 @@
 /**
  * The object name.
  */
-@property (nonatomic, readwrite, copy) NSString *name;
+@property (nonatomic, readwrite, copy, nullable) NSString *name;
 /**
  * <override-dummy />
  * Returns the object identifier.
@@ -590,7 +594,7 @@
  *
  * The returned collection contains COTag objects.
  */
-@property (nonatomic, readonly) NSSet *tags;
+@property (nonatomic, readonly) NSSet<COTag *> *tags;
 
 
 /** @taskunit Property-Value Coding */
@@ -602,7 +606,7 @@
  *
  * See also -entityDescription and -persistentPropertyNames.
  */
-@property (nonatomic, readonly) NSArray *propertyNames;
+@property (nonatomic, readonly) NSArray<NSString *> *propertyNames;
 /**
  * <override-never />
  * Returns the persistent properties declared in the receiver entity description.
@@ -612,7 +616,7 @@
  *
  * See also -entityDescription and -propertyNames.
  */
-@property (nonatomic, readonly) NSArray *persistentPropertyNames;
+@property (nonatomic, readonly) NSArray<NSString *> *persistentPropertyNames;
 /**
  * <override-never />
  * Returns the property value.
@@ -622,7 +626,7 @@
  *
  * See also -setValue:forProperty:.
  */
-- (id)valueForProperty: (NSString *)key;
+- (nullable id)valueForProperty: (NSString *)key;
 /**
  * <override-never />
  * Sets the property value.
@@ -632,7 +636,7 @@
  *
  * See also -valueForProperty:.
  */
-- (BOOL)setValue: (id)value forProperty: (NSString *)key;
+- (BOOL)setValue: (nullable id)value forProperty: (NSString *)key;
 
 
 /** @taskunit Validation */
@@ -648,7 +652,7 @@
  *
  * See -validateValue:forProperty: and ETValidationResult.
  */
-- (NSArray *)validateAllValues;
+- (NSArray<ETValidationResult *> *)validateAllValues;
 /**
  * Validates the proposed value against the property, then returns a validation 
  * result array.
@@ -671,7 +675,8 @@
  *
  * See -validateValue:forProperty: and ETValidationResult.
  */
-- (NSArray *)validateValue: (id)value forProperty: (NSString *)key;
+- (NSArray<ETValidationResult *> *)validateValue: (nullable id)value
+                                     forProperty: (NSString *)key;
 /**
  * <override-dummy />
  * Validates the receiver when it belongs to the inserted or updated objects in 
@@ -714,7 +719,7 @@
  * -[COObjectGraphContext updatedObjectUUIDs] and 
  * -[COObjectGraphContext changedObjectUUIDs].
  */
-- (NSArray *)validate;
+- (NSArray<ETValidationResult *> *)validate;
 /**
  * Calls -validateValue:forProperty: to validate the value, and returns the 
  * validation result through aValue and anError.
@@ -723,7 +728,9 @@
  * GNUstep programs.<br />
  * For Etoile programs or new projects, you should use -validateValue:forProperty:.
  */
-- (BOOL)validateValue: (id *)aValue forKey: (NSString *)key error: (NSError **)anError;
+- (BOOL)validateValue: (id _Nullable *_Nonnull)aValue
+               forKey: (NSString *)key
+                error: (NSError **)anError;
 
 
 /** @taskunit Direct Access to the Variable Storage */
@@ -738,7 +745,7 @@
  * This is a low-level method whose use should be restricted to serialization 
  * code and accessors that expose properties with no related instance variable.
  */
-- (id)valueForVariableStorageKey: (NSString *)key;
+- (nullable id)valueForVariableStorageKey: (NSString *)key;
 /**
  * <override-never />
  * Sets a value in the variable storage.
@@ -992,7 +999,7 @@
  *
  * This is used to present the revision to the user in the UI.
  */
-@property (nonatomic, readonly) NSString *revisionDescription;
+@property (nonatomic, readonly, nullable) NSString *revisionDescription;
 /** 
  * Returns the receiver tags in a coma separated list.
  *
@@ -1018,3 +1025,5 @@
 @property (nonatomic, readonly) BOOL isZombie;
 
 @end
+
+NS_ASSUME_NONNULL_END

Core/CORelationshipCache.h

@@ -24,7 +24,7 @@
 
 @property (nonatomic, readonly) NSDictionary *descriptionDictionary;
 
-@property (readwrite, nonatomic, weak) COObject *sourceObject;
+@property (readwrite, nonatomic, weak) __kindof COObject *sourceObject;
 @property (readwrite, nonatomic, copy) NSString *sourceProperty;
 @property (readwrite, nonatomic, copy) NSString *targetProperty;
 

Core/COSerialization.h

@@ -12,6 +12,8 @@
 
 @class COItem;
 
+NS_ASSUME_NONNULL_BEGIN
+
 /**
  * @group Core
  * @abstract Additions to convert inner objects into a "semi-serialized" 
@@ -93,25 +95,26 @@
 
 /** @taskunit Serialization */
 
-- (id)serializedValueForValue: (id)aValue
+- (id)serializedValueForValue: (nullable id)aValue
           propertyDescription: (ETPropertyDescription *)aPropertyDesc;
-- (id)serializedTypeForPropertyDescription: (ETPropertyDescription *)aPropertyDesc value: (id)value;
+- (NSNumber *)serializedTypeForPropertyDescription: (ETPropertyDescription *)aPropertyDesc
+                                             value: (nullable id)value;
 - (SEL)serializationGetterForProperty: (NSString *)property;
 - (COItem *)storeItemWithUUID: (ETUUID *)aUUID
-                        types: (NSMutableDictionary *)types
-                       values: (NSMutableDictionary *)values
+                        types: (NSMutableDictionary<NSString *, NSNumber *> *)types
+                       values: (NSMutableDictionary<NSString *, id> *)values
                    entityName: (NSString *)anEntityName
            packageDescription: (ETPackageDescription *)package;
-- (COItem *)additionalStoreItemForUUID: (ETUUID *)anItemUUID;
+- (nullable COItem *)additionalStoreItemForUUID: (ETUUID *)anItemUUID;
 
 /** @taskunit Deserialization */
 
-- (COObject *)objectForSerializedReference: (id)value
-                                    ofType: (COType)type
-                       propertyDescription: (ETPropertyDescription *)aPropertyDesc;
-- (id)valueForSerializedValue: (id)value
-                       ofType: (COType)type
-          propertyDescription: (ETPropertyDescription *)aPropertyDesc;
+- (nullable __kindof COObject *)objectForSerializedReference: (id)value
+                                                      ofType: (COType)type
+                                         propertyDescription: (ETPropertyDescription *)aPropertyDesc;
+- (nullable id)valueForSerializedValue: (id)value
+                                ofType: (COType)type
+                   propertyDescription: (ETPropertyDescription *)aPropertyDesc;
 - (SEL)serializationSetterForProperty: (NSString *)property;
 - (void)validateStoreItem: (COItem *)aStoreItem;
 
@@ -129,3 +132,5 @@
 - (id)roundTripValueForProperty: (NSString *)key;
 
 @end
+
+NS_ASSUME_NONNULL_END

Core/COSerialization.m

@@ -432,7 +432,8 @@ - (COType)serializedTypeForUnivaluedPropertyDescription: (ETPropertyDescription
     }
 }
 
-- (id)serializedTypeForPropertyDescription: (ETPropertyDescription *)aPropertyDesc value: (id)value
+- (NSNumber *)serializedTypeForPropertyDescription: (ETPropertyDescription *)aPropertyDesc
+                                             value: (id)value
 {
     COType type = 0;