value of type has no member 'quickLookPreview'

[paukala]

Description

Compilation of a source file containing .quickLookPreview() leads to the following error:

ExampleViewModifier.swift:8:17: error: value of type 'ExampleViewModifier.Content' (aka '_ViewModifier_Content<ExampleViewModifier>') has no member 'quickLookPreview'
        content.quickLookPreview($quickLookItem)
        ~~~~~~~ ^~~~~~~~~~~~~~~~
error: fatalError

Reproduction

ExampleViewModifier.swift

import SwiftUI
import QuickLook

struct ExampleViewModifier: ViewModifier {
    @State private var quickLookItem: URL?

    func body(content: Content) -> some View {
        content.quickLookPreview($quickLookItem)
    }
}

$ xcrun -toolchain org.swift.5101202403041a swiftc ExampleViewModifier.swift

org.swift.5101202403041a is a toolchain built from the swift-5.10-RELEASE tag downloaded from here: https://download.swift.org/swift-5.10-release/xcode/swift-5.10-RELEASE/swift-5.10-RELEASE-osx.pkg
However, also other versions seem to produce the same error.

Expected behavior

Compiles successfully, i.e. same behaviour as when using toolchain distributed as part of Xcode 15.3:

$ swiftc --version
swift-driver version: 1.90.11.1 Apple Swift version 5.10 (swiftlang-5.10.0.13 clang-1500.3.9.4)
Target: arm64-apple-macosx14.0

$ swiftc ExampleViewModifier.swift
<exit code 0>

Environment

$ xcrun -toolchain org.swift.5101202403041a swiftc --version
Apple Swift version 5.10 (swift-5.10-RELEASE)
Target: arm64-apple-macosx14.0

Additional information

When passing the -Rmodule-loading flag to swiftc, some differences in regards to the loaded modules can be observed:

Toolchain shipped with Xcode 15.3

$ swiftc ExampleViewModifier.swift -Rmodule-loading
...

ExampleViewModifier.swift:2:8: remark: loaded module 'QuickLook'; source: '/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX14.4.sdk/System/Library/Frameworks/QuickLook.framework/Modules/module.modulemap', loaded: '/var/folders/jh/vhc819237asdhjauw_0auqw20000gn/C/clang/ModuleCache/2BQW784XUIRDS/QuickLook-1TH8O9AVEIM3C.pcm'
import QuickLook
       ^
ExampleViewModifier.swift:2:8: remark: '_QuickLook_SwiftUI' has a required transitive dependency on 'Quartz'
import QuickLook
       ^
<unknown>:0: remark: 'QuickLookUI' has a required transitive dependency on 'PDFKit'
<unknown>:0: remark: loaded module 'PDFKit'; source: '/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX14.4.sdk/System/Library/Frameworks/PDFKit.framework/Modules/module.modulemap', loaded: '/var/folders/jh/vhc819237asdhjauw_0auqw20000gn/C/clang/ModuleCache/2BQW784XUIRDS/PDFKit-398FJ8DT2QBNH.pcm'
<unknown>:0: remark: 'QuickLookUI' has a required transitive dependency on 'QuickLookUI'
<unknown>:0: remark: 'QuickLookUI' has a required transitive dependency on 'Swift'
<unknown>:0: remark: 'QuickLookUI' has a required transitive dependency on '_Concurrency'
<unknown>:0: remark: 'QuickLookUI' has a required transitive dependency on '_StringProcessing'
<unknown>:0: remark: 'QuickLookUI' has a required transitive dependency on '_SwiftConcurrencyShims'
<unknown>:0: remark: loaded module 'QuickLookUI' (overlay for a clang dependency); source: '/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX14.4.sdk/usr/lib/swift/QuickLookUI.swiftmodule/arm64e-apple-macos.swiftinterface', loaded: '/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/lib/swift/macosx/prebuilt-modules/14.4/QuickLookUI.swiftmodule/arm64e-apple-macos.swiftmodule'
<unknown>:0: remark: loaded module 'Quartz'; source: '/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX14.4.sdk/System/Library/Frameworks/Quartz.framework/Modules/module.modulemap', loaded: '/var/folders/jh/vhc819237asdhjauw_0auqw20000gn/C/clang/ModuleCache/2BQW784XUIRDS/Quartz-154VNH160KV8P.pcm'
ExampleViewModifier.swift:2:8: remark: '_QuickLook_SwiftUI' has a required transitive dependency on 'QuickLook'
import QuickLook
       ^
ExampleViewModifier.swift:2:8: remark: '_QuickLook_SwiftUI' has a required transitive dependency on 'Swift'
import QuickLook
       ^
ExampleViewModifier.swift:2:8: remark: '_QuickLook_SwiftUI' has a required transitive dependency on 'SwiftUI'
import QuickLook
       ^
ExampleViewModifier.swift:2:8: remark: '_QuickLook_SwiftUI' has a required transitive dependency on '_Concurrency'
import QuickLook
       ^
ExampleViewModifier.swift:2:8: remark: '_QuickLook_SwiftUI' has a required transitive dependency on '_StringProcessing'
import QuickLook
       ^
ExampleViewModifier.swift:2:8: remark: '_QuickLook_SwiftUI' has a required transitive dependency on '_SwiftConcurrencyShims'
import QuickLook
       ^
ExampleViewModifier.swift:2:8: remark: loaded module '_QuickLook_SwiftUI'; source: '/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX14.4.sdk/System/Library/Frameworks/_QuickLook_SwiftUI.framework/Modules/_QuickLook_SwiftUI.swiftmodule/arm64e-apple-macos.swiftinterface', loaded: '/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/lib/swift/macosx/prebuilt-modules/14.4/_QuickLook_SwiftUI.swiftmodule/arm64e-apple-macos.swiftmodule'
import QuickLook
       ^

"Open source" toolchain `org.swift.5101202403041a`

$ xcrun -toolchain org.swift.5101202403041a swiftc ExampleViewModifier.swift -Rmodule-loading
...

ExampleViewModifier.swift:2:8: remark: loaded module 'QuickLook'; source: '/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX14.4.sdk/System/Library/Frameworks/QuickLook.framework/Modules/module.modulemap', loaded: '/var/folders/jh/vhc819237asdhjauw_0auqw20000gn/C/clang/ModuleCache/3MN83M481CP0T/QuickLook-1TH8O9AVEIM3C.pcm'
import QuickLook
       ^
ExampleViewModifier.swift:8:17: error: value of type 'ExampleViewModifier.Content' (aka '_ViewModifier_Content<ExampleViewModifier>') has no member 'quickLookPreview'
        content.quickLookPreview($quickLookItem)
        ~~~~~~~ ^~~~~~~~~~~~~~~~
error: fatalError

[paukala]

swift-6.0-DEVELOPMENT-SNAPSHOT-2024-04-15-a produces the same error.

[divadretlaw]

One issue is that quickLookPreview is not part of either import QuickLook or SwiftUI

The view extension (quickLookPreview) is actually found in _QuickLook_SwiftUI. When adding said import it appears to compile just fine.

[paukala]

The view extension (quickLookPreview) is actually found in _QuickLook_SwiftUI. When adding said import it appears to compile just fine.

Thanks for your answer. This seems to work fine as a workaround. However, as quickLookPreview is part of the QuickLook import with the toolchain distributed as part of Xcode, do you happen to know the reason why the _QuickLook_SwiftUI important is needed for the open source toolchain/is this intended behavior?

Could this also affect other frameworks present in /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS.sdk/System/Library/Frameworks, starting with _, such as _HomeKit_SwiftUI.framework?

[thekief]

In general it would be really nice to ensure that the compiler looks for libraries in the default path of the actual Xcode installation instead of a generated one. I looked over the available Swift frontend options [1] and it looks like some of these options may allow for a workaround but this is less then ideal.

-disable-implicit-swift-modules
-swift-module-file
-explicit-swift-module-map-file
-import-module

[1] https://github.com/apple/swift/blob/15fd443be60cfb52852c853c4fa0d6a1622ada10/include/swift/Option/FrontendOptions.td

[tbkka]

The _QuickLook_SwiftUI framework is a "cross-framework import" that with Apple's toolchain gets imported automatically whenever both import QuickLook and import SwiftUI appear in the same file. I'm not sure why you're not getting this behavior; @nkcsgexi might know if there's some additional flag you need to have this work with the open-source toolchain.

[divadretlaw]

Thank you, there actually is a flag that enables said behavior

-enable-cross-import-overlays

Automatically import declared cross-import overlays.

$ xcrun -toolchain org.swift.5101202403041a swiftc ExampleViewModifier.swift -Xfrontend -enable-cross-import-overlays

compiles the given example.