Undefined symbol: _OBJC_CLASS_$_SBTUITestTunnelServer

[Adham AboulEinein]

Hello,

I'm trying to integrate SBTUITestTunnel in my Swift project, but whenever I add it using cocoapods and add the imports in my AppDelegate (as instructed in the Setup document) and build I get the following error:

  "_OBJC_CLASS_$_SBTUITestTunnelServer", referenced from:
      objc-class-ref in MLAppDelegate.o
ld: symbol(s) not found for architecture x86_64
clang: error: linker command failed with exit code 1 (use -v to see invocation

Any ideas what is the problem?

[Lakshya Kapoor]

@AboulEinein Are you using a custom build config name? I just ran into the same issue when using QA and a co-worker helped me realize we need to set ENABLE_UITUNNEL=1 in the Podfile as mentioned here. Additionally, I also had to set ENABLE_UITUNNEL_SWIZZLING=1 to avoid an error where CLLocationManager+Swizzles.m:15 was not being included as it is gated behind #if ENABLE_UITUNNEL && ENABLE_UITUNNEL_SWIZZLING.

In short, this is what you need in post_install to make it work:

+if config.name == 'QA'
-  config.build_settings['GCC_PREPROCESSOR_DEFINITIONS'] ||= ['$(inherited)', 'ENABLE_UITUNNEL=1']
+  config.build_settings['GCC_PREPROCESSOR_DEFINITIONS'] ||= ['$(inherited)', 'ENABLE_UITUNNEL=1', 'ENABLE_UITUNNEL_SWIZZLING=1']
+end

You can still have ENABLE_UITUNNEL_SWIZZLING=0 in GCC_PREPROCESSOR_DEFINITIONS for your project if you want to disable swizzling like I am.

@tcamin Should the doc be updated to include ENABLE_UITUNNEL_SWIZZLING=1 in post_install or is this a bug?

[Eric Slosser]

I'm hitting this same error, regards of whether I integrate via Cocopods or SPM.

Adding ENABLE_UITUNNEL_SWIZZLING=1 to my UITest target's GCC_PREPROCESSOR_DEFINITIONS didn't help, (not that I'd expect it to.)

Xcode 13.2.1

[Aistė Stikliūtė]

I am getting the same error, integration via SPM. XCode 13.1. Custom build config name.
ENABLE_UITUNNEL_SWIZZLING=1 and DEBUG=1 is set.

[Adham AboulEinein]

@kapoorlakshya I'm using custom build config name and I've followed the docs you sent and I'm still getting the same error.

[gomera]

Same here, integration with spm and I have the same error ...

[Lakshya Kapoor]

@AboulEinein Is the pod added directly in the app target? I was getting the error when not adding the pod directly to the app target. This is the setup that's working for me:

# App target
def ui_test_app_helper_pods
  pod 'SBTUITestTunnelServer', '~> 8.2.0', configurations: %w[Debug QA]
  pod 'SBTUITestTunnelCommon', '~> 8.2.0', configurations: %w[Debug QA]
  pod 'GCDWebServer', '~> 3.5', inhibit_warnings: true, configurations: %w[Debug QA]
end

project 'MyProject'
target 'MyApp' do
  use_frameworks!
  inhibit_all_warnings!

  # CocoaPods won't link transitive dependencies of 'MyApp' or 'UITestAppHelpers'
  # that have 's.static_framework = true' such as 'SBTUITestTunnelServer'. Manually
  # add them here to fix this issue.
  ui_test_app_helper_pods
end

target 'UITestAppHelpers' do
  use_frameworks!
  inhibit_all_warnings!
  ui_test_app_helper_pods
end

Note: A co-worker (build eng) helped me figure this out and the comments above explain what's happening based on our troubleshooting steps.

Then in UITestAppHelpers, I am importing SBT and calling takeoff inside a wrapper method. The wrapper method is then called in AppDelegate:

#if canImport(SBTUITestTunnelServer)
import SBTUITestTunnelServer
#endif

@objc public final class UITestAppHelper: NSObject {
  @objc public class func startProxyServerForUITesting() {
#if canImport(SBTUITestTunnelServer)
    SBTUITestTunnelServer.takeOff()
#endif
  }
}

- (BOOL)application:(UIApplication *)application
    didFinishLaunchingWithOptions:(nullable NSDictionary<UIApplicationLaunchOptionsKey, id> *)launchOptions {
#if DEBUG || QA
  [UITestAppHelper startProxyServerForUITesting];
#endif

...redacted

I got the following error if the pod wasn't directly scoped under MyApp:

ld: warning: Could not find or use auto-linked framework 'FBLPromises'
ld: warning: Could not find or use auto-linked framework 'SBTUITestTunnelServer'
Undefined symbols for architecture arm64:
  "_OBJC_CLASS_$_SBTUITestTunnelServer", referenced from:
      objc-class-ref in UITestAppHelpers(UITestAppHelper.o)
ld: symbol(s) not found for architecture arm64
clang: error: linker command failed with exit code 1 (use -v to see invocation)

I would like to have it work by just adding to UITestAppHelpers target, but it does not work. Hope this helps.

[gomera]

This is not a cocoapod only related issue, it is happening with Swift Package Manager as well. The documentation is simple, add server into the app target and client into the ui-test target.

In my case, app and ui tests are compiling and running perfectly, but the unit-tests target which does not use SBTUITestTunnel at all, fails compiling because it does not find the server dependency. I even tried with a new empty project with unit tests, ui tests and not default configs and everything works.

At this point, not sure what to try next ...

[Tomas Camin]

Sorry for the late reply. Can anyone share a sample project (either CocoaPods or SPM) that replicates the issue? As @gomera commented staring with a blank project everything seems to work both with SPM and CocoaPods.