2.0 - SelectionSet Equatable crash when comparing objects

[AnthonyMDev]

Summary

Taken from this comment in 2.0 megathread

@ppmtrifork says:

I found another issue, this time causing a crash. It happens when attempting to access the hashValue or comparing two instances of a SelectionSet that contain a Field with .object type.

This is the error message:

Thread 1: Fatal error: Expected object data for object field: Field(name: "statusLabel", alias: nil, arguments: nil, type: ApolloAPI.Selection.Field.OutputType.object(GraphQL.ListItemFragment.StatusLabel))
This is the schema for that object:

type ListItem implements Hashable & IComponent {
  action: Action
  hashCode: Int!
  label: String
  primary: String!
  secondary: String
  statusLabel: StatusLabel
  tertiary: String
  thumbnailURL: String
}

type StatusLabel {
  context: SeverityContext!
  text: String!
}

enum SeverityContext {
  ...
}

Any thoughts on what might be causing this?

Version

2.0 beta 2

Steps to reproduce the behavior

I've been able to reproduce it whenever I have a comparison between two SelectionSet matching that criteria, or even comparing against nil, and also when accessing hashValue.

[AnthonyMDev]

@ppmtrifork @fourbytes I'm having a hard time reproducing this. The data structures should be set up properly to avoid this failure when fetched from the cache or the network.

How are you retrieving the objects when this failure is occurring? Are they fetched from the network? Manually initialized using raw json? Initialized using the generated initializers? etc.

[fourbytes]

Yep fetched from the network in my case. Here's some extra debugging info:

Crash stack:

Task 6 Queue : com.apple.main-thread (serial)
#0	0x00000001a29270dc in _swift_runtime_on_report ()
#1	0x00000001a2a0d9d4 in _swift_stdlib_reportFatalErrorInFile ()
#2	0x00000001a2a3f130 in closure #1 (Swift.UnsafeBufferPointer<Swift.UInt8>) -> () in Swift._assertionFailure(_: Swift.StaticString, _: Swift.String, file: Swift.StaticString, line: Swift.UInt, flags: Swift.UInt32) -> Swift.Never ()
#3	0x00000001a2a3e22c in _assertionFailure ()
#4	0x0000000100ab77e4 in addData #1 <ERPSchema.StaffFragment>(for:inList:) in SelectionSet.add(field:to:) at /Users/orainford/Library/Developer/Xcode/DerivedData/Fourbs_Central_Swift-amfsbyvvryukddcunqzfllnvvtoe/SourcePackages/checkouts/apollo-ios/Sources/ApolloAPI/SelectionSet+Equatable.swift:85
#5	0x0000000100ab6f3c in SelectionSet.add(field:to:) at /Users/orainford/Library/Developer/Xcode/DerivedData/Fourbs_Central_Swift-amfsbyvvryukddcunqzfllnvvtoe/SourcePackages/checkouts/apollo-ios/Sources/ApolloAPI/SelectionSet+Equatable.swift:68
#6	0x0000000100ab6c08 in SelectionSet.addFulfilledSelections(of:to:) at /Users/orainford/Library/Developer/Xcode/DerivedData/Fourbs_Central_Swift-amfsbyvvryukddcunqzfllnvvtoe/SourcePackages/checkouts/apollo-ios/Sources/ApolloAPI/SelectionSet+Equatable.swift:44
#7	0x0000000100ab67a8 in SelectionSet.fieldsForEquality() at /Users/orainford/Library/Developer/Xcode/DerivedData/Fourbs_Central_Swift-amfsbyvvryukddcunqzfllnvvtoe/SourcePackages/checkouts/apollo-ios/Sources/ApolloAPI/SelectionSet+Equatable.swift:27
#8	0x0000000100ab6880 in static SelectionSet.== infix(_:_:) at /Users/orainford/Library/Developer/Xcode/DerivedData/Fourbs_Central_Swift-amfsbyvvryukddcunqzfllnvvtoe/SourcePackages/checkouts/apollo-ios/Sources/ApolloAPI/SelectionSet+Equatable.swift:16
#9	0x000000010d9ff208 in protocol witness for static Equatable.== infix(_:_:) in conformance StaffFragment ()
#10	0x00000001a2b9ed98 in protocol witness for static Swift.Equatable.== infix(τ_0_0, τ_0_0) -> Swift.Bool in conformance <τ_0_0 where τ_0_0: Swift.Equatable> Swift.Optional<τ_0_0> : Swift.Equatable in Swift ()
#11	0x0000000102b7c79c in AuthViewModel.shouldNotifyObservers<τ_0_0>(_:_:) at /var/folders/q8/g861hhzd4zz55qnzdvxjj_sr0000gn/T/swift-generated-sources/@__swiftmacro_12FourbsShared13AuthViewModel10ObservablefMm_.swift:21
#12	0x0000000102b66d8c in AuthViewModel.currentUserStaff.setter at /var/folders/q8/g861hhzd4zz55qnzdvxjj_sr0000gn/T/swift-generated-sources/@__swiftmacro_12FourbsShared13AuthViewModelC16currentUserStaff18ObservationTrackedfMa_.swift:11
#13	0x0000000102b783d4 in AuthViewModel.loadCurrentUserStaff(forceRefresh:) at /Users/orainford/Developer/fourbs-group/erp-ios/FourbsShared/Sources/Auth/ViewModels/AuthViewModel.swift:389
#14	0x0000000102b7a058 in AuthViewModel.refreshCurrentUserStaff() at /Users/orainford/Developer/fourbs-group/erp-ios/FourbsShared/Sources/Auth/ViewModels/AuthViewModel.swift:412
#15	0x0000000102b71874 in closure #1 in AuthViewModel.setupAuthStateChangeListener() at /Users/orainford/Developer/fourbs-group/erp-ios/FourbsShared/Sources/Auth/ViewModels/AuthViewModel.swift:120
#16	0x0000000102b7d2c8 in partial apply for closure #1 in AuthViewModel.setupAuthStateChangeListener() ()
#17	0x0000000102b7e56c in thunk for @escaping @isolated(any) @callee_guaranteed @async () -> (@out A) ()
#18	0x0000000102b8300c in partial apply for thunk for @escaping @isolated(any) @callee_guaranteed @async () -> (@out A) ()

Additional warning in logs on crash:

ApolloAPI/SelectionSet+Equatable.swift:85: Fatal error: Expected object data for object field: Field(name: "homeAddress", alias: nil, arguments: nil, type: ApolloAPI.Selection.Field.OutputType.object(ERPSchema.StaffFragment.HomeAddress))
warning: TypeSystemSwiftTypeRef::operator(): had to engage SwiftASTContext fallback for type $s9ApolloAPI8DataDictV10FieldValueaD▿ 2 elements
  - key : "homeAddress"
  - value : <null>

Memory dump of the affected SelectionSet:

Affected query (optional fragment, nothing special as far as I can tell, using pg_graphql as backend):

query staffList($orderBy: [StaffOrderBy!], $filter: StaffFilter) {
    staffCollection(orderBy: $orderBy, filter: $filter) {
        pageInfo {
            hasNextPage
        }
        edges {
            node {
               ...StaffFragment
            }
        }
    }
}

fragment StaffFragment on Staff {
	id
	...
	homeAddress {
		...AddressFragment
	}
}

fragment AddressFragment on Address {
	id
	name
	locality
	administrativeArea
	isoCountryCode
	postalCode
	title
	subAdministrativeArea
	subLocality
	thoroughfare
	subThoroughfare
	coordinates
}

[AnthonyMDev]

Ahh, it looks like this is happening when the object field is optional and <null>. That makes perfect sense! Thank you for the additional information.

I should be able to get this sorted out now

[AnthonyMDev]

This is fixed in the 2.0.0-beta-3.

[github-actions]

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