Test failed when using swift macros as external dependencies

Metadata

Source

tuist/tuist #7164

Updated

Jun 11, 2026

Domains

Generated projects

Details

What happened?

My app and modules have some swift macros as external dependencies. Everything works well when run through Xcode. But it failed when run by xcodebuild no matter on CI nodes or my machine.

How do we reproduce it?

 cd fixtures/multiplatform_app_with_macros_and_embedded_watchos_app \
 && tuist install \
 && tuist generate

⌘ + U in Xcode and it will build and test successfully
Open terminal and run xcodebuild -workspace AppWithWatchApp.xcworkspace -scheme AppWithWatchApp-Workspace -configuration Debug -scmProvider system -disableAutomaticPackageResolution -sdk 'iphonesimulator' -destination 'platform=iOS Simulator,id=theUUIDofYourSimulator' -enableCodeCoverage YES -skipPackagePluginValidation -skipMacroValidation -retry-tests-on-failure -test-iterations 11 clean test
The tests build failed with below errors: Multiple commands produce '/yourDerivedData/AppWithWatchApp-ddfnoigpczzvcocxhnuttxpcsxlc/Build/Products/Debug-iphonesimulator/CasePathsMacros'

Multiple commands produce '/yourDerivedData/AppWithWatchApp-ddfnoigpczzvcocxhnuttxpcsxlc/Build/Products/Debug-iphonesimulator/ModuleAMacros'
Same errors when changed to other swift macros such as MetaCodable and swift-composable-architecture

Error log

Multiple commands produce '/yourDerivedData/AppWithWatchApp-ddfnoigpczzvcocxhnuttxpcsxlc/Build/Products/Debug-iphonesimulator/CasePathsMacros'

Multiple commands produce '/yourDerivedData/AppWithWatchApp-ddfnoigpczzvcocxhnuttxpcsxlc/Build/Products/Debug-iphonesimulator/ModuleAMacros'

macOS version

14.6.1

Tuist version

4.37.0

Xcode version

15.4

Comments

D

dosubot[bot] Dec 15, 2024

Hey @mo5tone! I’m here to help you with your software development issues and questions. Let’s tackle this bug together!

The “Multiple commands produce” error typically occurs when there are conflicting build settings or configurations that result in the same output file being generated by multiple build steps. Here are a few steps you can take to resolve this issue when using Swift macros as external dependencies:

Check Build Phases: Ensure that the build phases in your Xcode project or workspace do not have duplicate entries for the same output files. This can happen if a macro or its dependencies are being built multiple times.
Review Tuist Configuration: Make sure that your Tuist configuration does not inadvertently create duplicate targets or build settings that could lead to this conflict. This includes checking your Project.swift and any related configuration files for duplicate entries.
Use Tuist Caching: Tuist offers a caching feature that can help mitigate build time issues and potentially resolve conflicts. You can use the tuist cache command to cache your Swift Macros and other dependencies, which might help in avoiding duplicate builds:
```
tuist cache
```
Derived Data Management: Clear your derived data to ensure there are no stale build artifacts causing conflicts. You can do this by running:
```
rm -rf ~/Library/Developer/Xcode/DerivedData
```
Xcode and xcodebuild Differences: Sometimes, Xcode and xcodebuild handle build settings differently. Ensure that any custom build settings or flags used in Xcode are also correctly applied in your xcodebuild command.

If these steps do not resolve the issue, you may need to further investigate the specific build settings and configurations in your project that could be causing the conflict.

To continue talking to Dosu, mention @dosu.

M

mo5tone Dec 15, 2024

Same errors when try with Xcode 16.2 on macOS 14.6.1.

M

mo5tone Dec 15, 2024

After comparing with BuildAcceptanceTestMultiplatformAppWithMacrosAndEmbeddedWatchOSApp, I found removing -sdk 'iphonesimulator' make everyhing work well again. But I don’t know why 🤔

F

fortmarek Dec 16, 2024

I believe the issue is that you’re specifying an SDK for a multiplatform target. I’d be curious to know how xcodebuild command behaves when the macro is integrated with the default Xcode integration, instead of the XcodeProj-based one.

@pepicrft, do you have an idea why adding an SDK would make the issue fixed in https://github.com/tuist/tuist/pull/6109 reappear?

M

mo5tone Dec 17, 2024

I believe the issue is that you’re specifying an SDK for a multiplatform target.

My project only supports iOS which have one app target and a few static framework targets.

F

fortmarek Dec 17, 2024

My project only supports iOS which have one app target and a few static framework targets.

I see – macros are in the end macOS executables, so technically you are still compiling for multiple platforms even if your project itself is only building for iOS. I agree this is a problem solving – though, I don’t know how, yet 😅

E

escapeanaemia Mar 18, 2025

Any updates from here? I also have a same problem 👀

E

Engwar Dec 1, 2025

I have the same problem with two local frameworks which inslude macros

JB

jrcmramos-bumble Dec 15, 2025

We also faced the same problem here.

Just confirmed that this problem is reproducible on other iOS only fixture projects. Example

How to reproduce it:

xcodebuild -workspace App.xcworkspace -scheme App -configuration Debug -sdk 'iphonesimulator' -destination 'platform=iOS Simulator,id=DEVICE_ID'  build-for-testing

S

shlykovdanylo Jan 18, 2026

We ran into the same issue recently, and after some debugging we concluded that the -sdk flag forces a specific SDK for all targets being built. Macro targets cannot be built with a non-macOS SDK, which leads to build failures.

When building for a simulator or a device, you don’t need to specify the SDK explicitly - just provide the destination and let xcodebuild determine the correct SDK for each target based on project configuration. For example, when you build inside Xcode, it uses the SDKs defined in the project configuration, and xcodebuild should behave the same way.

We removed the -sdk flag from all of our workflows, and everything works as before - now including macro targets.