Is anyone using cocoapods dependencies in tests? I...

# multiplatform

[Jeff Lockhart]

Is anyone using cocoapods dependencies in tests? I've asked about a linker error with this, but haven't received any answers. Is anyone doing this successfully?

[Tijl]

probably still relevant:

https://kotlinlang.slack.com/archives/C3SGXARS6/p1599727679156900?thread_ts=1599727395.156400&cid=C3SGXARS6

[Jeff Lockhart]

Thanks for the link. So it seems I need to provide the path to the cocoapods dependency framework, where it’s located in the iOS app Pods path I’m assuming. I still can’t get it to find it using the example linkerOpts code, getting the same linker error:

> Task :shared:linkDebugTestIos
e: /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/ld invocation reported errors
The /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/ld command returned non-zero exit code: 1.
output:
Undefined symbols for architecture x86_64:
  "_OBJC_CLASS_$_CBLMutableDocument", referenced from:
      objc-class-ref in result.o
  "_OBJC_CLASS_$_CBLMutableDictionary", referenced from:
      objc-class-ref in result.o
  "_OBJC_CLASS_$_CBLMutableArray", referenced from:
      objc-class-ref in result.o
  "_OBJC_CLASS_$_CBLBlob", referenced from:
      objc-class-ref in result.o
ld: symbol(s) not found for architecture x86_64
> Task :shared:linkDebugTestIos FAILED

The frameworksPath I’m providing is relative to the KMM shared module’s build folder to the iOS app’s Pods folder, where the CouchbaseLite.framework folder is: ../../ios/app/Pods/CouchbaseLite-Enterprise/iOS

The other code in the example gives me the error:

Could not create task ':shared:iosTest'.
> Replacing an existing task with an incompatible type is not supported.  Use a different name for this task ('iosTest') or use a compatible type (org.gradle.api.DefaultTask)

Not sure what’s causing that, but seems I need to get past the linker error first anyway.

@alex009 if you wouldn’t mind explaining some more about what the process would be to utilize cocoapods dependencies in Kotlin tests, and the steps to get it working, I’d be grateful to you.

[Tijl]

as a sort of “sanity” check you can manually copy all the frameworks you use into a directory called Frameworks next to test.kexe

[Tijl]

ah but that is post linking

[Tijl]

you can also manually add the binary.linkerOpts("-F$frameworksPath") for every framework

[Tijl]

you might also need to throw in linkerOpts("-framework", "$frameworkname}")

[Tijl]

val copyFrameworksForX64Test by tasks.registering(Copy::class) {
            val tree = fileTree("$buildDir/cocoapods/synthetic/iosX64/${project.name.replace('-','_')}/build/Release-iphonesimulator")

            from(tree) {
                include("**/*.framework/**")
                include("**/*.framework.DSYM/**")
                include("**/*.bundle")
            }
            eachFile {
                path = path.substring(1).substringAfter("/", path)
            }
            into ("$buildDir/bin/iosX64/debugTest/Frameworks")
        }

        val linkDebugTestIosX64 by tasks.getting {
            dependsOn(copyFrameworksForX64Test)
        }

copies this from an old gradle task I made to do the copying

iosX64  {
        binaries {
            getTest("DEBUG").apply {
                linkerOpts("-ObjC")
                linkerOpts("-framework", "someFramework")
                linkerOpts("-F$buildDir/bin/iosX64/debugTest/Frameworks")

and from an old build file

[Kris Wong]

iosX64("ios") {
        compilations {
            "test" {
                cinterops.create("OHHTTPStubs") {
                    includeDirs("c_interop/OHHTTPStubs/Headers")
                }
            }
        }
        binaries.getTest(DEBUG).linkerOpts("-Lc_interop/OHHTTPStubs")
    }

[Kris Wong]

and my .def file contains linkerOpts = -lOHHTTPStubs -ObjC

[Jeff Lockhart]

Thanks for these tips! So adding linkerOpts("-framework", "CouchbaseLite") got the linking working. Then iosTest is failing because the library isn’t loaded.

> Task :shared:linkDebugTestIos
> Task :shared:iosTest FAILED
dyld: Library not loaded: @rpath/CouchbaseLite.framework/CouchbaseLite
  Referenced from: /.../shared/build/bin/ios/debugTest/test.kexe
  Reason: image not found
Child process terminated with signal 6: Abort trap

Do you have any tips for loading the library at test runtime?

[Jeff Lockhart]

I figured this out! The missing key was setting the -rpath to the frameworks path, which is used to load the library at runtime. Combining it all:

iosX64("ios") {
    binaries {
        getTest("DEBUG").apply {
            val frameworksPath = "${buildDir.absolutePath}/cocoapods/synthetic/IOS/shared/Pods/CouchbaseLite-Enterprise/iOS"
            linkerOpts("-F$frameworksPath")
            linkerOpts("-rpath", frameworksPath)
            linkerOpts("-framework", "CouchbaseLite")
        }
    }
}

I switched the path to the cocoapods/synthetic/… path, since that’s contained within the shared module build path and doesn’t depend on my iOS app at all. If I was using more than one framework, it’d be a bit more complicated, since the frameworks would need to be copied into the same directory. But this could be done in combination with setting the -rpath to that directory as part of the build process.

Thanks again for your help!

[Tijl]

yeah that might have been fixed by copying the frameworks (as per the task I shared), but -rpath is a way better method!

reading the docs (of ld) it seems multiple -rpath arguments should work too.

[Kris Wong]

i've never had to set the rpath or manually copy any framework. strange

[Tijl]

I only have this with cocoapods dependencies, never with e.g carthage. I’m very puzzled as to why.

[Tijl]

Anyone know if there is a youtrack for this yet btw?

[Kris Wong]

ok, I am not using cocoapods dependencies in my KMM project

[Kris Wong]

but I am using cinterop

[Jeff Lockhart]

That might be the difference @Kris Wong. Looks like your cinterop is compiled as a library, linked with -l, which is slightly different than the framework format from cocoapods, linked with -framework.

The default rpath expects the frameworks to be in a folder called Frameworks in the same directory as the test.kexe binary build/bin/ios/debugTest. Now I see that’s where your code is copying the frameworks. So yeah, setting the -rpath option allows you to reference the frameworks from the original location without needing to copy.

Since -rpath can be provided multiple times, then seems the cocoapods plugin should be able to append these combination of -F, -rpath, and -framework linker opts to the test binary for each of the cocoapods dependencies added. I haven’t found a YouTrack issue for this. So I created one.

[Kris Wong]

yeah I've got libOHTTPStubs.a within the framework, so it just made sense to link it that way. but that also explains why I didn't have your issue - static linking. so that could be another option for you.

[Kris Wong]

i honestly don't even remember where I got this framework originally 😛

[Ben Deming]

Thanks for the great workaround for Cocoapods users!

In case anyone is using pods w/vendored frameworks in addition to pods compiled from source, or pods whose name is different from their module name, here's a slight extension to the workaround described above:

binaries {
            getTest("DEBUG").apply {
                // Map of pod names to their `module_name`s
                val regularPodToModuleNameMap = mapOf(
                    "CocoaLumberjack" to null,
                    "Split" to null,
                    "DatadogSDKObjc" to "DatadogObjc",
                    "DatadogSDK" to "Datadog"
                )

                // Map of vendored pod names to their `module_name`s (maybe redundant, they might need to be the same?)
                val vendoredPodToModuleNameMap = mapOf("TwilioChatClient" to null)

                // common is the name of our project, substitute accordingly
                val commonSyntheticPath = "${buildDir.absolutePath}/cocoapods/synthetic/IOS/common"
                val regularFrameworksPath = "$commonSyntheticPath/build/Release-iphonesimulator"
                val vendoredFrameworkPath = "$commonSyntheticPath/Pods"

                regularPodToModuleNameMap.forEach { entry ->
                    val podDirectoryName = entry.key
                    val moduleName = entry.value ?: entry.key

                    val frameworkPath = "$regularFrameworksPath/$podDirectoryName"
                    linkerOpts("-framework", moduleName)
                    linkerOpts("-F$frameworkPath")
                    linkerOpts("-rpath", frameworkPath)
                }

                vendoredPodToModuleNameMap.forEach { entry ->
                    val podDirectoryName = entry.key
                    val moduleName = entry.value ?: entry.key

                    val frameworkPath = "$vendoredFrameworkPath/$podDirectoryName"
                    linkerOpts("-framework", moduleName)
                    linkerOpts("-F$frameworkPath")
                    linkerOpts("-rpath", frameworkPath)
                }

                // Don't forget framework flags for system frameworks any pods depend on
                linkerOpts("-framework", "UIKit")
            }
        }

Could use some DRYing up but may be helpful nevertheless.

[Tijl]

https://youtrack.jetbrains.com/issue/KT-37513 moved to “Planned” 🎉