I'm experiencing a new error in SwiftData since updating to Xcode 16/iOS 17 DB1. When passing in a model (Student) to a view and then displaying an array of Points using ForEach, I get the following fatal error:
SwiftData/ModelCoders.swift:2438: Fatal error: Failed to locate relationship for StringCodingKey(stringValue: "group", intValue: nil) on Entity - name: Point
superentity:
subentities:
storedProperties:
CompositeAttribute - name: type, options: [], valueType: PointType, defaultValue: nil
Properties:
Attribute - name: type, options: [], valueType: String, defaultValue: nil, hashModifier: nil
Relationship - name: outcome, options: [], valueType: Outcome, destination: Outcome, inverseName: nil, inverseKeypath: nil
CompositeAttribute - name: proficiency, options: [], valueType: Proficiency, defaultValue: nil
Properties:
Attribute - name: proficiency, options: [], valueType: String, defaultValue: nil, hashModifier: nil
Attribute - name: date, options: [], valueType: Date, defaultValue: nil, hashModifier: nil
Attribute - name: note, options: [], valueType: String, defaultValue: nil, hashModifier: nil
Relationship - name: student, options: [], valueType: Optional<Student>, destination: Student, inverseName: points, inverseKeypath: Optional(\Student.points)
Attribute - name: group, options: [], valueType: Array<PersistentIdentifier>, defaultValue: [], hashModifier: nil
inheritedProperties:
uniquenessConstraints:
indices:
Xcode flags this line of the macro-generated getter of the outcome property on Point:
@storageRestrictions(accesses: _$backingData, initializes: _outcome)
init(initialValue) {
_$backingData.setValue(forKey: \.outcome, to: initialValue)
_outcome = _SwiftDataNoType()
}
get {
_$observationRegistrar.access(self, keyPath: \.outcome)
return self.getValue(forKey: \.outcome) // Fatal error: Failed to locate relationship for StringCodingKey...
}
set {
_$observationRegistrar.withMutation(of: self, keyPath: \.outcome) {
self.setValue(forKey: \.outcome, to: newValue)
}
}
This worked just fine in iOS 17. Here's a snippet of the Student implementation:
@Model
class Student: Identifiable, Comparable {
var name: String
var number: Int
@Relationship(deleteRule: .cascade, inverse: \Point.student) var points: [Point]
@Relationship(deleteRule: .cascade, inverse: \Mark.student) var marks: [Mark]
@Relationship(deleteRule: .nullify, inverse: \StudentGroup.students) var groups: [StudentGroup] = []
var archived: Bool
}
and the implementation of Point:
@Model
class Point: Identifiable, Comparable {
var student: Student?
var type: PointType
var outcome: Outcome
var proficiency: Proficiency
var group: [Student.ID] = []
var date: Date
var note: String
}
and finally the implementation for Outcome:
@Model
class Outcome: Identifiable, Comparable {
var name: String
var index: Int
var rubric: Rubric?
var proficiencies: [Proficiency]
}
I've tried adding a relationship in Outcome as an inverse of the outcomes property on Points (although this does not make sense in my implementation, which is why I initially did not set a relationship here) and the problem persisted.
Any ideas what this error means and how I might go about fixing it?
Theohhno
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assignment.dueDate = Calendar.current.date(bySettingHour: 23, minute: 59, second: 59, of: dueDate)
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assignment.weight = Double(weight) ?? Assignment.defaultWeight
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assignment.weight = Assignment.defaultWeight
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Hardware Model:			iPhone11,8
Process:						 Pupl [45462]
Path:								/private/var/containers/Bundle/Application/3D8B69C4-8AE5-40E7-BBDF-93CC12D79E1C/Pupl.app/Pupl
Identifier:					com.kevinolmats.Pupl
Version:						 285 (1.0.1)
AppStoreTools:			 12A7402a
AppVariant:					1:iPhone11,8:14
Code Type:					 ARM-64 (Native)
Role:								Foreground
Parent Process:			launchd [1]
Coalition:					 com.kevinolmats.Pupl [2248]
Date/Time:					 2020-10-25 13:38:09.3546 -0700
Launch Time:				 2020-10-25 13:33:01.8074 -0700
OS Version:					iPhone OS 14.0.1 (18A393)
Release Type:				User
Baseband Version:		3.00.01
Report Version:			104
Exception Type:	EXC_CRASH (SIGABRT)
Exception Codes: 0x0000000000000000, 0x0000000000000000
Exception Note:	EXC_CORPSE_NOTIFY
Triggered by Thread:	0
Application Specific Information:
abort() called
Last Exception Backtrace:
0	 CoreFoundation								 0x1884d65ac 0x1883b5000 + 1185196
1	 libobjc.A.dylib							 0x19c55042c 0x19c546000 + 42028
2	 CoreData											 0x18e58a648 0x18e460000 + 1222216
3	 CoreData											 0x18e58f6f4 0x18e460000 + 1242868
4	 Pupl													 0x100a56cac specialized WeightCategoryEditorViewModel.init(course:color:context:) + 339116 (WeightCategoryEditorViewModel.swift:30)
5	 Pupl													 0x100a4d7a0 closure #1 in closure #1 in closure #1 in CourseEditorWeightCategoryView.body.getter + 300960 (CourseEditorViewModel.swift:0)
6	 SwiftUI											 0x18ee430b0 0x18e864000 + 6156464
7	 SwiftUI											 0x18ed4b9c4 0x18e864000 + 5142980
8	 SwiftUI											 0x18edd0e90 0x18e864000 + 5688976
9	 SwiftUI											 0x18ee6b3f8 0x18e864000 + 6321144
10	SwiftUI											 0x18ee6b6e4 0x18e864000 + 6321892
11	UIKitCore										 0x18aff60d0 0x18a273000 + 14168272
12	UIKitCore										 0x18aff5c8c 0x18a273000 + 14167180
13	UIKitCore										 0x18aff6438 0x18a273000 + 14169144
14	UIKitCore										 0x18b2bb544 0x18a273000 + 17073476
15	UIKitCore										 0x18ae00400 0x18a273000 + 12112896
16	UIKitCore										 0x18adef1bc 0x18a273000 + 12042684
17	UIKitCore										 0x18ae22648 0x18a273000 + 12252744
18	CoreFoundation								 0x188452444 0x1883b5000 + 644164
19	CoreFoundation								 0x18844c858 0x1883b5000 + 620632
20	CoreFoundation								 0x18844ce08 0x1883b5000 + 622088
21	CoreFoundation								 0x18844c4bc 0x1883b5000 + 619708
22	GraphicsServices							 0x19eed1820 0x19eece000 + 14368
23	UIKitCore										 0x18adf0734 0x18a273000 + 12048180
24	UIKitCore										 0x18adf5e10 0x18a273000 + 12070416
25	SwiftUI											 0x18f1ad32c 0x18e864000 + 9737004
26	SwiftUI											 0x18f1ad2b8 0x18e864000 + 9736888
27	SwiftUI											 0x18ed26b08 0x18e864000 + 4991752
28	Pupl													 0x100a1311c main + 61724 (Assignment.swift:0)
29	libdyld.dylib								 0x188113e60 0x188113000 + 3680
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struct ContentView: View {
		@Environment(\.managedObjectContext) var context
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				[...]
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				.sheet(isPresented: assignmentEditorIsPresented) {
						[...]
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		}
}
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