Trying out kmm with a non trivial project,
The task is to show a list of repos, and I want to have a preview of the screen in swift-ui.
I have a viewModel that get's injected a repository that will eventually query github api. For the preview I inject a fake repository that should answer with a list of hardcoded objects.
The code is in this PR https://github.com/alexandru-calinoiu/SharedAppSample/pull/1
Preview for RepoListView will crash:
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Translated Report (Full Report Below)
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Incident Identifier: 4990E330-CD93-4D80-92C9-1426BBC3FBBA
CrashReporter Key: E30E0C83-3AF1-4C22-98AC-D674ED184D1C
Hardware Model: Macmini8,1
Process: iosApp [41515]
Path: /Users/USER/Library/Developer/Xcode/UserData/Previews/Simulator Devices/0DF05C52-98D2-4DF5-AA63-6F22DBFE76C1/data/Containers/Bundle/Application/461BB8B1-6BFE-4BB1-B1FD-0882D664AE26/iosApp.app/iosApp
Identifier: orgIdentifier.iosApp
Version: 1.0 (1)
Code Type: X86-64 (Native)
Role: Foreground
Parent Process: launchd_sim [16338]
Coalition: com.apple.CoreSimulator.SimDevice.0DF05C52-98D2-4DF5-AA63-6F22DBFE76C1 [86637]
Responsible Process: SimulatorTrampoline [670]
Date/Time: 2022-10-10 17:12:15.1370 +0300
Launch Time: 2022-10-10 17:12:14.5247 +0300
OS Version: macOS 12.5.1 (21G83)
Release Type: User
Report Version: 104
Exception Type: EXC_BAD_ACCESS (SIGSEGV)
Exception Subtype: KERN_INVALID_ADDRESS at 0x0000000000000118
Exception Codes: 0x0000000000000001, 0x0000000000000118
VM Region Info: 0x118 is not in any region. Bytes before following region: 140737487011560
REGION TYPE START - END [ VSIZE] PRT/MAX SHRMOD REGION DETAIL
UNUSED SPACE AT START
--->
VM_ALLOCATE 7fffffeb8000-7fffffeb9000 [ 4K] r-x/r-x SM=ALI
Exception Note: EXC_CORPSE_NOTIFY
Termination Reason: SIGNAL 11 Segmentation fault: 11
Terminating Process: exc handler [41515]
Triggered by Thread: 0
Thread 0 Crashed:: Dispatch queue: BSXPCCnx:com.apple.dt.xcode-previews.systemservices (BSCnx:client:com.apple.dt.uv.agent-preview-nonui-service)
0 RepoListView.1.preview-thunk.dylib 0x13d1f7d7b Kotlin_Interop_CreateKStringFromNSString + 107
1 iosApp 0x10eb2c3cd Kotlin_ObjCExport_refFromObjC + 61
2 iosApp 0x10ea5124f objc2kotlin.1693 + 335
3 iosApp 0x10e67ec70 @nonobjc ExploreSharedRepo.init(owner:name:description:primaryLanguage:lastActivity:) + 160
4 iosApp 0x10e67e325 ExploreSharedRepo.__allocating_init(owner:name:description:primaryLanguage:lastActivity:) + 133
5 iosApp 0x10e67e1ba one-time initialization function for repos + 218 (RepoListView.swift:61)
6 libdispatch.dylib 0x110f95a3a _dispatch_client_callout + 8
7 libdispatch.dylib 0x110f96db3 _dispatch_once_callout + 20
8 iosApp 0x10e67e361 Screen_Previews.repos.unsafeMutableAddressor + 49 (RepoListView.swift:60)
9 iosApp 0x10e67e3bb one-time initialization function for viewModel + 27 (RepoListView.swift:65)
10 libdispatch.dylib 0x110f95a3a _dispatch_client_callout + 8
11 libdispatch.dylib 0x110f96db3 _dispatch_once_callout + 20
12 iosApp 0x10e67e421 Screen_Previews.viewModel.unsafeMutableAddressor + 49 (RepoListView.swift:65)
13 RepoListView.1.preview-thunk.dylib 0x13d55de5f static Screen_Previews.__preview__previews.getter + 31 (RepoListView.swift:68)
14 iosApp 0x10e67e6a9 protocol witness for static PreviewProvider.previews.getter in conformance Screen_Previews + 9
15 SwiftUI 0x1152b92a3 0x1148eb000 + 10281635
16 iosApp 0x10e67e6e5 protocol witness for static _PreviewProvider._previews.getter in conformance Screen_Previews + 37
17 SwiftUI 0x1152b9ac1 0x1148eb000 + 10283713
18 PreviewsInjection 0x10fba27f9 0x10fb78000 + 174073
19 PreviewsInjection 0x10fba26e9 0x10fb78000 + 173801
20 PreviewsInjection 0x10fb9991a 0x10fb78000 + 137498
..... (char limit was hit, so no full message)
By reading the log I guess it has something to do with converting strings from to kotlin, but what?
Try adding isStatic = false to your framework block here
The SwiftUI preview doesn't work with static frameworks produced by Kotlin. There's some discussion about it here